+
VI. Review and Synthesis
of
Available Evidence
+
A. Factors Altering Risk of Suicide and Attempted
Suicide
As shown in Table 10, suicide rates vary with age, gender,
and race or ethnicity. Annual rates in the general U.S. population
rise sharply in adolescence and young adulthood, plateau through
midlife, then rise again in individuals over age 65. The increased
rates of suicide in youths are even more dramatic in some ethnic
and racial subgroups of the population. For example, the suicide
rate among American Indian males between ages 15 and 34 years averaged
about 36 per 100,000 during the period from 1979 to 1993, whereas
Alaska Native males between ages 14 and 19 years had an even more
dramatic rate, at 120 per 100,000 (661). Black male youths, who
were historically at low risk for suicide, now have a suicide rate
comparable to their white peers. Although the suicide rate in adolescents,
like the overall U.S. suicide rate, has dropped in the past decade,
the relative suicide risk of youths remains high, and this has been
attributed to increases in alcohol and substance abuse (662), breakdown
in extended family and intergenerational support, and increased
availability of firearms, especially for young African American
males (663).
Individuals over age 65 are disproportionately represented
among those who die by suicide. Compared with suicide rates in men
ages 55 to 64 years, suicide rates in men over age 85 are two- to
threefold higher for all races except African Americans. For elderly
women, suicide rates are relatively unchanged with increasing age,
with the exception of Asian women over age 85, whose suicide rate
increases threefold from middle age.
Overall suicide rates among those over age 65 have decreased
substantially over the course of the last century, with a further
decrease over the past decade. Although the reasons for the decline
are unknown, a variety of mechanisms have been postulated, including
improved access to social and health care resources by older adults
with the implementation of Social Security and Medicare legislation and
the more widespread use of safe and effective antidepressant medications
(664). The incidence of suicide among elderly persons may increase
again, however, as the large, post–World War II baby boom
generation continues to age. Relative to age groups born in earlier
or later periods, baby boomers have been distinguished by suicide
rates that have been comparatively higher at all ages (665). Of
additional concern is the fact that elders are the fastest growing
segment of the U.S. population. Thus, as large numbers of this high-risk
cohort enter the phase of life associated with greatest risk, the
absolute number of suicides among older adults may increase dramatically
(666).
Suicidal ideation and suicide attempts are more frequent in
younger age groups than in later life (14). Kuo et al. (29), using
prospectively gathered data from the Epidemiologic Catchment Area (ECA)
survey, found a progressive decrease in the annual incidences of
suicidal ideation and suicide attempts with increasing age. Compared
with the rate in individuals over age 65, the rate of suicide attempts
was 10-fold greater in those ages 18 to 29 years, at approximately
310 per 100,000 person-years. The rate of suicidal ideation in individuals
ages 18 to 29 was approximately 630 per 100,000 person-years, a
rate that was sixfold greater than that in those over age 65. Duberstein
et al. (13), in a study of adults age 50 years and older, also found
that people are less likely to report suicidal ideation as they
age.
In other studies, estimates of the prevalence of suicidal
ideation in older adults have varied with the population sampled
and the site, time frame, and study methods. Lish and colleagues
(667) found that 7.3% of an older sample in Department
of Veterans Affairs (VA) primary care practices had thoughts of
suicide, and elders with a history of mental health treatment were
at far greater risk. Callahan and colleagues (668) used a far more
stringent definition of suicidal ideation, limited ascertainment
to within the past week, and required the ideation to include a
specific suicide plan. They found that 0.7%–1.2% of
elders in primary care had suicidal ideation, all of whom had a simultaneous
mood disorder. Skoog et al. (669), in a survey of nondemented
Swedes age 85 years and older, inquired about the presence of both
active and passive suicidal ideation in the month preceding the
interview. They found that 16% of the subjects had thoughts
of suicide. Again, the rate was higher in subjects with mental disorder,
in those taking anxiolytic and neuroleptic agents, and in those
with significant physical illness. Among community-dwelling Floridians
60 years of age and older, less than 6% reported ever having
had suicidal thoughts in a study by Schwab et al. (670), while in
the Berlin Aging Study (671) 21% of subjects over age 70
reported having had suicidal ideation. Again, psychiatric illness
was present in virtually all subjects, suggesting a need for careful screening
for psychiatric disorder in elders with suicidal ideation.
In the United States, epidemiologic data show that suicide
is more frequent in men than in women. For example, data from the
National Center for Health Statistics for the year 2000 showed an
age-adjusted suicide rate for males that was approximately 4.5-fold
that for females (18.08 per 100,000 and 4.03 per 100,000, respectively)
(11). This differential is comparable to the male-to-female ratio for
suicide found in the National Longitudinal Mortality Study for the
years 1979 to 1989 (672). Within the U.S. population, males are
disproportionately represented among deaths by suicide in all racial
and ethnic groups, with rates that range from more than 5.5-fold
greater than that for females among African Americans and Hispanics
to threefold greater than that for females among Asian/Pacific
Islanders. This is not the case in other parts of the world, however.
For example, in China the suicide rate for women is 25% higher
than that for men (18).
The male-to-female predominance in suicide in the United States
persists across the lifespan. Adolescent and young adult males are
about 5.5 times more likely to die from suicide than females, whereas
in midlife the male-to-female ratio is approximately 3.5 to 1. After
about age 65, however, there is a steadily widening male-to-female
ratio of suicide rates in all groups except Asians, with differences
of more than 10-fold after age 80.
Differences in suicide risk with gender may be explained in
part by factors that contribute to risk in general but that are
present to differing degrees in men and in women. For example, men
are less likely than women to seek help, admit the severity of their
symptoms, or accept treatment, increasing their likelihood of suicide.
In contrast, women tend to be less impulsive, have more social support, and
have lower rates of comorbid alcohol and substance use disorders,
all of which may have a protective effect (21). Among African American
women, the potential protective factors of religion and extended
kin networks have been suggested as possible explanations for this
group's very low rate of suicide (22).
Despite their lower rate of suicide, women have higher rates
of depressive illness than men (23, 673). Furthermore, in a 10-year
follow-up study using data from the National Longitudinal Mortality Study,
unemployment was associated with a greater and longer-lasting effect
on the suicide rate of women compared to men (24). Compared to men,
women also have an increased likelihood of having been physically
or sexually abused, which may also increase the risk for
suicide (36). The relative lethality of the suicide methods chosen
by women remains less than those chosen by men; however, the recent,
more frequent use of firearms among women suggests that this distinction
may be diminishing (11, 674).
Suicide rates have also been examined in pregnant women and
during the postpartum period. Dannenberg et al. (675) reviewed New
York City medical examiner records of 293 pregnant or recently pregnant
women ages 15 to 44 years who died of injury during a 4-year period.
Of these, 15 died by suicide, a rate that was not significantly
different from the expected age- and race-specific rates in the
general population. However, Marzuk et al. (676) analyzed autopsy
data from female residents of New York City who were of childbearing
age and found the standardized mortality rate for suicide during
pregnancy to be one-third the expected rate. Appleby (677), using
retrospective population data for England and Wales from 1973 to
1984, also noted decreased rates of suicide among pregnant women
and among women during the first year after childbirth, with SMRs
of 0.05 and 0.17, respectively. In contrast to decreased
suicide rates for women in general during pregnancy and the puerperium,
Appleby et al. (27) subsequently found an extremely high suicide
rate among women who had been psychiatrically hospitalized during
the postpartum period. In this study of 1,567 women admitted
to Danish psychiatric hospitals within the first year after childbirth,
the SMR for suicide within 1 year was more than 70 times the expected
rate. Although risk was greatest within the first month postpartum,
it persisted throughout the initial year after childbirth. In addition,
women who died by suicide after childbirth often used violent methods.
Thus, although evidence is limited, women with severe postpartum
psychiatric disturbances appear to be at significantly increased
risk during the initial year after childbirth. Other groups with
a particularly increased postpartum risk include teenagers and women
of lower socioeconomic status (27, 28). For women as a group, however,
a protective effect seems to be present during pregnancy and the
postpartum period (25).
In terms of suicide attempts, women in the United States are
reported to attempt suicide three times as often as men. This female
predominance of suicide attempters varies with age, however, and
in older adults the ratio of female-to-male suicide attempters approaches
1:1 (11). Similar trends are observed in the incidence of suicidal
ideation. For example, Kuo et al. (29), using data from 3,481 prospectively
followed individuals from the Baltimore ECA study, found that females
ages 18 to 29 years had a higher incidence of suicidal ideation
and suicide attempts than their male peers. However, this female-to-male
predominance in suicidal ideation and suicide attempts was not observed
for older age groups or for the sample as a whole.
As noted earlier, women are more likely to have experienced
domestic violence or physical or sexual abuse, all of which have
been associated with higher rates of suicidal ideation and suicide attempts
(32–34). In a study of psychosocial outcomes in 1,991 same-sex
twin pairs, Nelson et al. (35) found that childhood sexual abuse
was three times more common in women and was associated with an
increased risk of attempting suicide. Borderline personality disorder
is also present more often in women (515) and is itself associated
with increased rates of suicidal ideation, suicide, suicide attempts,
and other self-injurious behaviors. In addition, borderline
personality disorder is particularly common in women who have experienced
childhood sexual abuse, physical abuse, or both (31). As a result,
physical and sexual abuse and domestic violence should be given
particular consideration in the assessment and treatment of women
with suicidal ideation, suicide attempts, and other self-injurious behaviors.
+
c) Race, ethnicity, and culture
Race, ethnicity, and culture are all associated with variations
in rates of suicide. In the United States for the year 2000, the
overall age-adjusted rates of suicide were highest in Native Americans and
non-Hispanic whites, at 13.6 and 12.1 per 100,000, respectively
(11). In contrast, the age-adjusted rate of suicide in Hispanics
was substantially less, at 6.13 per 100,000, and was similar to
the rates for non-Hispanic African Americans and Asian/Pacific
Islanders, at 5.8 and 6.0 per 100,000, respectively.
For immigrant groups, suicide rates in general tend to mirror
rates in the countries of origin, with trends converging toward
the host country over time (40, 41). In a large epidemiological
study, Singh and Siahpush (39) found that between 1979 and 1989,
foreign-born men in the United States were 52% less likely
to die by suicide than native-born men, but the difference narrowed
in the older age cohorts. Data for immigrant women were not statistically
significant because of the small number of deaths.
In the United States, racial and ethnic differences are also
seen in the rates of suicide across the lifespan (Table 10). Among
European-American non-Hispanic whites, Hispanics, and Asian/Pacific Islanders,
the highest suicide rates occur during the senior years, in those
over age 65. In contrast, among Native Americans and African Americans,
the highest suicide rates occur during adolescence and young adulthood.
For example, in Native American and African American males ages
15 to 24, suicide rates in the year 2000 were 36.81 and 14.66 per
100,000, respectively. Young African American men have been described
as being caught in a cycle of drug abuse, criminal activity, and self-devaluation
and may view an early death as inevitable or as an alternative to
the wearying struggle that life has become (678). Additional risk
factors for suicide in young African American males include substance
abuse (662, 679), presence of a firearm (663), and in particular
the combination of cocaine abuse and the presence of a firearm (679).
Suicidal ideation and suicide attempts are also common in urban
African American young adults, with 6-month prevalences of 1.9% and
0.4%, respectively (680).
In contrast to young African American males, African American
women have a very low rate of suicide. Gibbs (22) attributes this
low rate to the protective factors of religion, including the role
of religion in the civil rights movement, women's central
involvement in the church, and strong values for endurance in the
face of adversity. Women-dominated kinship networks are also believed
to be protective, providing flexible roles, resource sharing, and
social support (681).
Although black women are less likely to die from suicide than
white women, they attempt suicide and express negative emotional
states such as hopelessness and depression just as frequently. In addition,
both black men and black women are less likely than their white
counterparts to pursue professional counseling in the face of depression
or other mental illness. Instead, African Americans are more likely
to view depression as a "personal weakness" that
can be successfully treated with prayer and faith alone some or
almost all of the time (682). When depression is discussed, it may
be described in different terms such as having "the blues" or "the
aching misery" or "being down" (678). Consequently,
sensitivity to language and beliefs about illness are important
in recognizing depression and other risk factors for suicide among
African Americans.
Among Native Americans (American Indians and Alaska Natives),
suicide also is predominately an epidemic of the young and is the
second leading cause of death for Native Americans between ages
15 and 24 years. As with other racial and ethnic groups, Native
American and Alaska Natives are a very heterogeneous population,
with different tribal identities, varying degrees of urbanization, different
levels of tribal organization, and diverse approaches to historical
and cultural integration. For example, in a study of three groups
of Native Americans in New Mexico, the Apache had the highest suicide
rate (43.3 per 100,000) and the highest degree of acculturation
but also had the lowest degree of social integration and generally
viewed religion as unimportant (683). In contrast, the Navajo had
the lowest suicide rate (12.0 per 100,000) and the lowest level
of acculturation but had moderate social integration and were organized
into bands with a strong matrilineal clan influence. In the third
group, the Pueblo, the subgroup with the most acculturation, had
a higher suicide rate than the most traditional subgroup, again
suggesting an effect of acculturation on suicide risk. Acculturation
has also been proposed as a contributor to the extremely high suicide
rate in Alaska Native youths, which in one study approached 120
per 100,000 (661). Theories to explain these high rates tend to
rely on family disintegration, social disruption, and alcohol use
(684), as well as rapid social and cultural changes associated with
intensive energy development projects in the Arctic and the resulting
stress of acculturation. In contrast, in Hawaiian youths, the relationship
between acculturation and suicidal behavior is less clear, with
increased numbers of suicide attempts in those with stronger Hawaiian
cultural affiliation (685).
Research on suicide among Hispanics in the United States is
limited and rarely differentiates among different Hispanic
groups. In addition, many individuals of Hispanic origin
are undocumented workers who are not represented in census data
or epidemiological studies. Large-scale grouping of diverse ethnic
groups also obscures intracultural variations in important social
and economic categories. For example, Cuban American women and Mexican
Americans and Puerto Ricans of both genders were reported to have
lower than expected suicide rates, relative to 1-year prevalence of
major depression, than were whites, blacks, and Cuban American males
(23). In terms of suicidal ideation, higher levels have been reported
in Central American immigrants experiencing heightened levels of
acculturative stress (43). In addition, lifetime age- and gender-adjusted
rates of suicidal ideation were significantly lower for Mexican
Americans born in Mexico (4.5%) than for Mexican Americans
born in the United States (13%) or for non-Latino whites
(19.2%) (686). Similarly, rates of suicide attempt were
lower among Mexican Americans born in Mexico (1.6%) and
higher among both Mexican Americans born in the United States (4.8%)
and non-Latino whites (4.4%). The rate of suicide
attempt is also elevated among Hispanic youths, who had higher numbers
of reported suicide attempts compared to non-Hispanic youths
in a nationwide survey of high school students (687).
The suicide rate for Asians overall is the lowest of all of
the major American ethnic groups, but Asian Americans themselves
have diverse ethnic backgrounds, languages, and cultures. Some groups,
such as the Japanese, have been in the United States for generations.
Others, such as the Chinese, include both recent immigrants and
descendants of 19th-century immigrants, whereas the Vietnamese have
arrived in large numbers only since the 1960s. These individuals
bring with them attitudes toward coping and suicide from their home
countries, which can influence the circumstances of suicidal behavior
(688). In Japan, for example, suicide is permissible or even appropriate
in particular contexts, and ritual suicide has been an honorable
solution to certain social dilemmas. For example, the disgrace of
bankruptcy in Japan can shame the family for generations, making
suicide a preferable way to resolve debt. When it is culturally
important for a man to be physically healthy and able to support
his family, suicide may be viewed as an option if a serious physical
illness impairs his ability to function. For example, in Hawaii,
20.5% of suicides by Japanese American men occurred in
individuals with health problems, in contrast to only 11.8% of
suicides by Caucasian men and 3.0% by Hawaiian men (42).
In addition, for individuals who come from a culture in which mental
illness is highly stigmatized, receipt of a psychiatric diagnosis
may increase the risk for suicide. Although Chinese societies have
not generally codified suicide as socially acceptable, more recent
suicide rates in China are quite high, particularly in women and
in rural settings, where use of agricultural poisons is a common
suicide method (18).
In the United States, acculturation and acculturative stress
may be a contributor to suicide risk among Asian Americans. For
most Asian Americans, the family unit is central to identity. Children
are socialized into awareness that their individual actions reflect
upon the entire family, including extended family members (689).
While this feature may impede a family's willingness to
seek treatment for a troubled relative, the strong sense of family
as a support and source of obligation protects against suicide as
well. At the same time, family conflict as a reason for suicide
is more common in Eastern societies (42). For example,
if a young woman from a traditional society experiences conflicts
with her in-laws that have no apparent solution, the woman may be
more likely to view suicide as an option than would someone from
a different family system in which close family relationships are
not as imperative. Transition to the individualistic, communication-oriented
U.S. society is a major and stressful change for many families (44).
The group most at risk appears to be traditionalists who live in
tight-knit groups resistant to acculturative processes. They appear
to function relatively well until their elderly years, when the
culture clash between the values of the larger society and the Confucian
tradition of strong family identity results in alienation of elders
and contributes to suicide in the style of the old country (44).
For example, a major factor in the high suicide rate of elderly
Asian/Pacific Islander women was reported to be the failure
of younger family members to provide support for their elderly parents,
especially widowed mothers (690). Such deaths occurred predominantly
by hanging, which was traditionally seen as an act of revenge, since
someone who died by hanging was believed to return to haunt the
living as a ghost (690).
In summary, race, ethnicity, and culture may all influence
population-based rates of suicide and suicide attempts. Of equal
importance to the clinician, however, each of these factors may
modify suicide risk within the individual. Views of death and cultural
beliefs regarding suicide can vary widely, even among members of
apparently homogeneous racial, ethnic, or cultural groups. Thus,
as part of the assessment and treatment planning process, it can
be helpful for the psychiatrist to explore the patient's
beliefs about death and suicide and the role of cultural and family
dynamics in these beliefs.
Marital status has been correlated with variations in suicide
mortality in a number of studies. Smith et al. (691) used data from
the U.S. National Center for Health Statistics for the years 1979
to 1981 to calculate age-adjusted suicide rates for each marital status.
Regardless of age or racial group, the suicide rate was consistently
lowest in married individuals. An intermediate rate was seen in
those who had never been married, with a relative risk that was
about twice that in married individuals. The highest suicide rate
was found for divorced or widowed individuals, with a relative risk
that was about threefold greater than that in married individuals.
Whereas divorced women had a higher age-adjusted suicide rate than
widowed women, the opposite was true among men, with a particularly striking
rate of suicide in young widowed men.
Kposowa (672) applied Cox proportional hazards regression
models to data from the 1979–1989 follow-up of the National
Longitudinal Mortality Study and made adjustments for age, sex,
race, education, family income, and region of residence to estimate
the effect of marital status on suicide risk. Although in this sample
being single or widowed had no significant effect on suicide risk, divorced
and separated persons had suicide rates that were more than twice
that of married persons. Stratification of the sample by sex showed
that the effect of marital status on suicide rates occurred only
among men.
Luoma and Pearson (46) also examined whether marital status
is associated with variations in suicide rates. Suicide rates broken
down by race, 5-year age groups, sex, and marital status were calculated
by using data compiled from the U.S. National Center for Health
Statistics Multiple-Cause-of-Death Files for the years 1991 to 1996.
Widowed white and African American men under age 50 were found to
have substantial elevations in suicide rates, with 17-fold and ninefold
higher rates, respectively, compared with married men under age
50. At younger ages, for women as well as for men, being widowed
was associated with a higher suicide rate, compared with being married.
Using data from the National Suicide Prevention Project in
Finland, Heikkinen et al. (402) investigated age-related variations
in marital status as well as other social factors in a sample of
1,067 individuals who died by suicide during a 1-year period and
for whom relevant data were available. Compared with the general
population, individuals who died by suicide were more commonly divorced,
widowed, or never married. Among individuals under age 50 who died
by suicide, more males than females had never been married.
Among those over age 50, more women than men were widowed.
Other data from Finland obtained through the Finnish Population
Register and cause-of-death files also suggest that the rate of
suicide is elevated among widowed individuals (45). Among 95,647
persons who were widowed during 1972–1976 and followed
up to the end of 1976, 7,635 deaths were observed, of which 144
were due to suicide. During the initial month of bereavement, men
had a much greater increase in suicide mortality than women (17.2-fold
versus 4.5-fold), but this disproportionate ratio primarily resulted
from occurrences of homicide-suicide. In the remaining first year
of bereavement, men had a 3.1-fold increase in suicide mortality
and women a 2.2-fold increase, and rates remained higher than expected
throughout the follow-up period.
Overall, these studies suggest that married individuals have
a significantly lower rate of suicide than unmarried individuals.
In addition, elevations in the suicide rate are especially striking
for widowed men in general and young widowed men in particular.
What remains unclear is whether this protective effect of marriage
on the suicide rate relates to specific benefits of marriage, such
as a greater likelihood of social integration. In contrast, the
decrease in social integration and the psychological experience
of loss with widowhood and with divorce may increase the tendency
for suicide. The suicide rate among divorced individuals could also
be higher because individuals who stay married have a greater likelihood
of stable mental health at baseline. Other confounding factors,
such as differences in substance use or socioeconomic status with
marital status, could play additional roles that should be considered in
the assessment process.
It remains unclear whether suicide rates in gay, lesbian,
and bisexual individuals differ from the suicide rate among heterosexual
individuals. One psychological autopsy study compared gay males to
all other similarly aged males in the sample and did not find any
characteristics that distinguished the two groups (692). However,
research on suicide among gay, lesbian, and bisexual individuals
is particularly complex because of many factors, including small
sample sizes, difficulties in achieving random sampling, problems
in obtaining baseline prevalences, and problems in reliability of postmortem
reports of sexual orientation. In addition, individuals may choose
not to disclose their sexual orientation to researchers or may engage
in same-sex behavior but not identify themselves as gay or lesbian.
The risks for suicide attempts and suicidal ideation in gay,
lesbian, and bisexual individuals have been assessed by using several
approaches. Fergusson et al. (51), analyzing longitudinal data gathered on
a New Zealand birth cohort, found that those who identified themselves
as gay, lesbian, and bisexual or reported having a same-sex partner
since the age of 16 had elevated rates of suicidal ideation (odds
ratio=5.4) and suicide attempts (odds ratio=6.2).
A study by Cochran and Mays (50) examined lifetime prevalences of
suicide-related symptoms among men with same-gender partners and
found that approximately one-half (53.2%) of the men reported
experiencing at least one suicide-related symptom in their lifetime,
with a suicide attempt reported by 19.3%. In contrast,
in men with female partners only, 33.2% had at least one
suicide-related symptom and 3.6% reported a suicide attempt.
Corresponding figures for those with no sexual partners were 28.1% and
0.5%, respectively. Using the population-based Vietnam
Era Twin Registry, Herrell et al. (52) identified a subsample of 103
middle-aged male twin pairs in which one of the twins from each
pair reported having a male sexual partner after age 18 while the
other did not. Suicide attempts were more common in the men with
same-gender sexual orientation, with 15% reporting a suicide
attempt, compared with only 4% of their twin brothers.
In the Twin Registry sample as a whole, which included 16 twin pairs concordant
for having a male sexual partner after age 18 and 6,434 twin pairs
concordant for having no adult same-gender partners, the men with
same-gender sexual orientation had more than a fourfold increase
in suicidal ideation and more than a 6.5-fold increase in suicide
attempts.
Gay, lesbian, and bisexual youths may be at particular risk
for suicidal behaviors. Paul et al. (53), in a study of a large
urban population–based telephone probability sample of
gay men, found that 21% had made a suicide plan and 12% had
attempted suicide. Of the latter, almost one-half had made multiple
attempts, and most had made their first attempt before age 25. The
importance of sexual orientation to suicidal behaviors in youths
is also highlighted by the findings of a statewide population-based
study of public high school students by Remafedi et al. (48). In
this study, suicide attempts were reported by 28.1% of
bisexual/homosexual males, 20.5% of bisexual/homosexual
females, 14.5% of heterosexual females, and 4.2% of
heterosexual males. For males, but not for females, a bisexual/homosexual
orientation was associated with suicidal intent (odds ratio=3.61)
and with suicide attempts (odds ratio=7.10).
Thus, although evidence is limited, there is clearly an elevated
risk for suicide attempts among cohorts of gay, lesbian, and bisexual
individuals that is particularly striking among youths. In addition
to addressing risk factors such as psychiatric and substance use
disorders in the assessment and treatment planning processes, it
is also important for the clinician to address stresses that are
unique to being gay, lesbian, or bisexual (e.g., disclosure of sexual
orientation to friends and family, homophobia, harassment, and gender nonconformity).
Since suicide attempts themselves increase the risk for later suicide,
it is presumed that suicide rates may also be increased in gay,
lesbian, and bisexual individuals. However, this hypothesis remains
to be tested empirically.
Occupational groups differ in a number of factors contributing
to suicide risk. These factors include demographics (e.g., race,
gender, socioeconomic class, and marital status), occupational stress,
psychiatric morbidity, and occupationally associated opportunities
for suicide. Although many studies have reported increased rates
of suicide in specific occupational groups, most have not controlled
for other suicide risk factors. In one study, however, that controlled
for basic demographic correlates of suicide across 32 occupations
(54), risk was found to be highest among dentists and physicians,
compared with the rest of the working-age population, with multivariate
logistic regression odds ratios of 5.43 and 2.31, respectively.
The odds of suicide were also significantly higher in nurses (1.58
times the risk), social workers (1.52 times the risk), mathematicians
and scientists (1.47 times the risk), and artists (1.30 times the
risk). Rates of suicide among physicians have also been found to
be elevated, compared with rates for other white male professionals,
with white male physicians having a 70% greater proportionate
mortality ratio for suicide (58). In well-designed epidemiological
studies, police officers have generally not been found to be at
higher risk for suicide than age- and sex-matched comparison subjects
(54, 57).
Factors that may play a role in the increased suicide rates
in specific professions may include occupational stresses, as is
seen in helping professionals (54), or social isolation, as is seen
in sheepherders, who had the highest suicide rate of 22 occupational
groups studied in Washington State (56). Although data are inconsistent,
additional work stress may occur with infrequent role sets such as
female laborers or pilots (55, 57) or in nontraditional occupations
(693). In some occupations, suicide rates may be influenced by greater
access to lethal methods such as medications or chemicals, as in
health care professionals, scientists, and agricultural workers
(57).
Differential rates of psychiatric illness may be present in
some occupations and may predate employment. Artists, for example,
have higher rates of psychiatric morbidity and suicide than the general
population. Highly educated people with depressive disorders also
have a higher suicide rate. Among physicians, such individuals may
tend to specialize in psychiatry (56).
In general, specific occupations do seem to be associated
with an increased risk for suicide, but more research is needed
to distinguish occupational from nonoccupational stressors (56)
and to determine whether it is the occupation itself or associated
factors such as psychiatric morbidity that affect suicide risk.
+
2. Major psychiatric syndromes
Major depressive disorder and other depressive syndromes are
the most commonly and most consistently identified axis I diagnoses
in individuals who die by suicide (694, 695). For example, Robins
et al. (60) found that among 134 persons who died by suicide, 98% were
psychiatrically ill and most had depression or chronic alcoholism.
Barraclough et al. (65), in a similar study, found that of 100 individuals
who died by suicide, 93% were mentally ill and 85% had
either depression or alcoholism. Henriksson et al. (59), using psychological
autopsy methods to investigate current mental disorders among a
random sample of 229 persons who died by suicide during a 1-year
period in Finland, found that 93% of those persons had
received at least one axis I diagnosis and that 59% had a
depressive disorder.
In patients with bipolar disorder who die by suicide, the
majority are experiencing either a depressive or mixed episode of
illness (69, 72, 315). For example, Isometsa et al. (68) noted that among
31 patients with bipolar disorder identified in a group of 1,397
persons who died by suicide in Finland in a 12-month period, 79% died
while in a major depressive episode and 11% while in a mixed
state. In a study of more than 300 patients who were discontinued
from lithium treatment, Baldessarini et al. (696) found that the
majority of suicidal acts occurred either during a major depressive
episode (73%) or during a dysphoric-mixed episode
(16%).
In addition to being highly prevalent in individuals who die
from suicide, mood disorders have long been associated with an increased
risk for suicide. For example, in 1970, Guze and Robins (697) reviewed
17 studies that assessed the risk of suicide in individuals with
primary affective disorders and calculated the frequency of suicide
as a percentage of all deaths. High suicide rates were found, with
the ultimate risk of suicide estimated to be about 15%,
or approximately 30 times that seen in the general population. For
major depression, review of the literature suggests that overall
rates of suicide mortality range from 5% to 26% and
are about twice as high for men as for women (694). However, these
studies generally assessed severely ill patient populations and
individuals early in the course of their illness, when suicide rates
are known to be highest.
Several investigators have subsequently reexamined these estimates
of lifetime suicide risk in individuals with mood disorders. For
example, Inskip et al. (94), using cohort-based curve-fitting techniques
and data from previous studies, estimated the lifetime risk for
suicide in mood disorders to be 6%. In addition, Bostwick
and Pankratz (77) used data from prior studies to calculate case
fatality prevalences (the ratio of suicides to the total number
of subjects) to determine suicide risks for three groups of patients
with affective disordersoutpatients, inpatients, and suicidal
inpatients. With this method, which provides a less biased estimate
of risk, they found a gradation in suicide risk that varied with treatment
setting as well as with hospitalization for suicidality. For example,
in patients with mood disorders who were previously hospitalized
for suicidality, the estimated lifetime prevalence of suicide was
8.6%, compared to a lifetime risk of 4% for those
with a psychiatric hospitalization for any reason. For mixed inpatient/outpatient
populations, the prevalence of suicide was 2.2%, whereas
for the populations without affective illness, it was
less than 0.5%. For individuals with major depressive
disorder, Blair-West et al. (205) used age- and gender-stratified
calculations to arrive at comparable estimates for lifetime suicide
risk of 3.4%, with a lifetime risk for males more than
six times than for females (6.8% versus 1.1%).
Harris and Barraclough (64), in their meta-analysis of suicide
as an outcome in psychiatric illness, assessed relative suicide
risk in mood disorder by calculating SMRs. Their analysis used data
from published English-language studies that had mean or median
follow-up periods of at least 2 years and that provided sufficient
data to calculate ratios of observed to expected numbers of suicides.
For patients with major depressive disorder, 23 studies that included
a total of 351 suicides among more than 8,000 patients yielded an
SMR of 20.35, or a 20-fold increase in risk. A key finding was that risk
in patients with major depressive disorder was highest immediately
after hospital discharge (698, 699). For patients with bipolar disorder,
data from 15 studies including a total of 93 suicides among 3,700
subjects yielded an SMR for suicide of 15.05. Although patients
with dysthymia also had an elevated SMR for suicide, of 12.12, the
nine studies that contributed to this estimate were extremely heterogeneous
in their findings and most had extremely small samples, which raises
some question about the validity of this approximation.
Several studies have examined rates of suicide in longitudinal
follow-up in individuals hospitalized for mood disorder. Hoyer et
al. (75) used data from the Danish Psychiatric Case Register to determine
SMRs for suicide among 54,103 patients (19,638 male and 34,465 female
patients) who had an initial admission to a Danish psychiatric hospital
between 1973 and 1993 and who received a mood disorder diagnosis.
During the study period, 29% of the patients died, and
of those, suicide occurred in 20%. Standardized mortalities
for suicide were comparable for patients with ICD-8 diagnoses of
unipolar major depression, psychotic reactive depression, and bipolar
disorder, with SMRs of 19.33, 18.67, and 18.09, respectively. In
contrast, the SMR for suicide in patients with neurotic depression
was significantly less, at 10.51. In all diagnostic subgroups and
regardless of age and gender, the risk of suicide was greatest during
the first year after the initial admission, decreased over the subsequent
5 years, and then stabilized. Overall, the risk for suicide was
comparable in men and women, except in patients with bipolar disorder,
for whom the SMR for suicide was somewhat greater in women than
in men (20.31 versus 18.09).
In a similarly designed study using data from a Swedish inpatient
register, Osby et al. (73) obtained the date and cause of death
for patients hospitalized between 1973 and 1995 with a diagnosis
of bipolar disorder (N=15,386) or unipolar depressive
disorder (N= 39,182). SMRs for suicide were found to be
significantly increased in women and in patients with a unipolar
depressive disorder diagnosis (15.0 for male bipolar disorder patients,
20.9 for male unipolar depressive disorder patients, 22.4 for female
bipolar disorder patients, and 27.0 for female unipolar depressive
disorder patients). Suicide mortality was more pronounced in younger
individuals and with shorter intervals from the index hospitalization.
Although SMRs decreased in all age groups with increasing time of
follow-up, some suicide risk persisted even at long follow-up intervals.
Baxter and Appleby (188) used the Salford (U.K.) Psychiatric
Case Register to identify 7,921 individuals who had received psychiatric
or mental health care and determined their mortality rates (estimated
as rate ratios) over a follow-up period of up to 18 years. Among
individuals with affective disorders, there was a 12.2-fold elevation
in observed suicide mortality in men, compared to expected mortality
based on population rates. For women, the relative increase in suicide
mortality was even greater, with a 16.3-fold elevation.
Angst et al. (74) followed a sample of 406 hospitalized patients
with mood disorders (220 with bipolar disorder and 186 with unipolar
depressive disorder) on a prospective basis for 22 years or more
and found an overall standardized mortality rate for suicide of
18.04, comparable to the SMRs found in the Swedish and Danish longitudinal
follow-up studies. Sixty-one percent of the sample had manifested
psychotic symptoms at least once over their lifetime, suggesting
that this was a particularly ill group of patients. The suicide
rate was greatest near the age of illness onset; however, from ages
30 to 70 years, the rate was remarkably constant, suggesting a persistence
of risk throughout the illness course. The suicide mortality in
women was greater than that in men (SMR of 21.87 for women, compared
to 13.49 for men), in part reflecting the greater rate of suicide
for men in the general population. Patients with unipolar depressive
disorder had a significantly higher rate of suicide than patients
with bipolar I disorder or bipolar II disorder, with an SMR for
suicide of 26.7, compared with 12.3 for bipolar disorder patients.
The SMR for suicide did not differ significantly between bipolar
I disorder patients and bipolar II disorder patients.
Some evidence suggests that in individuals with mood disorders,
the rate of suicide may be increasing over time. For example, Harris
and Barraclough (64) noted that the suicide risk for patients with
major depression in cohorts treated before 1970 was increased by
17-fold in contrast to a 36-fold increase in risk for cohorts treated
after 1970. In the study described earlier, Hoyer et al. (75) noted
an increase in both the absolute and relative risks for suicide
over the 20-year study time period, and they suggested that the
increase may have been related to changes in the health care delivery system
and the availability of psychiatric inpatient services. In addition,
Baldessarini et al. (563) observed that the annualized rates of
suicide and suicide attempts in patients with major affective disorders
appear to have risen across the decades since 1970. This trend was
sustained and statistically significant for both suicides and suicide
attempts, as well as for treated and untreated samples considered
separately. Although this apparent secular trend could reflect increased
recruitment of more severely ill patients to more recent studies
or increased reporting of suicidal behaviors, the percentage
reduction of suicide risk with lithium treatment did not decline
across the years, suggesting that the patient populations are in
fact comparable and that the prevention of suicide in major affective
disorders is becoming increasingly challenging (558). Furthermore,
suicide attempts that do occur in individuals with major mood disorders
may be more lethal than suicide attempts by individuals in the general
population. The reported ratio of suicide attempts to deaths from
suicide averages between 3:1 and 5:1 among persons with mood disorders,
whereas in the general population the suicide attempt rate has been
estimated to be about 10–20 times (average, 18
times) greater than the suicide rate, or about 0.3% per
year (700).
For individuals with mood disorders, it is also important
to note factors that are particularly associated with increased
risk. Fawcett et al. (79, 313) determined time-related predictors
of suicide in a sample of 954 psychiatric inpatients in the NIMH
Collaborative Program on the Psychobiology of Depression, about
one-third of whom had bipolar disorder and the rest of whom had
other mood disorders. During the initial 10 years of follow-up,
34 patients died by suicide, an overall rate that was extremely
low, at 0.36% per year. The first year of follow-up was
the time of highest risk, with 38% of suicides occurring
during that period. Within 1 year of admission, six factors were
associated with suicide: panic attacks, severe psychic anxiety,
diminished concentration, global insomnia, moderate alcohol abuse,
and anhedonia. The three factors associated with suicide that occurred
after 1 year were severe hopelessness, suicidal ideation, and history
of previous suicide attempts. By 14 years, among individuals for
whom follow-up information was available, 36 had died by suicide, 120
had attempted suicide, and 373 had no recorded suicide attempt (247).
Analysis at that time point showed that patients who died by suicide
and patients with suicide attempts shared core characteristics,
including a history of previous suicide attempts, alcohol and substance
abuse, impulsivity, and psychic turmoil within a cycling/mixed
bipolar disorder. In contrast to suicide within 12 months of intake,
which was predicted by clinical variables, suicide beyond 12 months
was prospectively predicted by temperament attributes, such as higher
levels of impulsivity and assertiveness. Stressful life events (701),
executive dysfunction (702), and higher levels of depression (10,
78, 221, 222, 703) may also be associated with greater risk, as
may an awareness of the discrepancies between a previously envisioned "normal" future
and the patient's likely degree of future chronic disability
(273).
In summary, mood disorders are consistently identified as
conferring a significant increase in the risk for suicide
as well as for suicide attempts. However, among individuals
with mood disorders, a variety of factors commonly modify that risk
and should be taken into consideration during
the assessment and treatment planning processes. These factors include
the specific mood disorder diagnosis and duration of illness, the
type and severity of the mood episode, the prior history of treatment,
the presence of comorbid diagnoses or specific psychiatric symptoms
such as severe anxiety or agitation, and the occurrence of significant
psychosocial stressors. It is important to note, however, that this
increased risk of suicidal behaviors among individuals with mood
disorders has been consistently shown to be modifiable with treatment
(see Section VI.D, "Somatic Therapies").
Schizophrenia has also been associated with an increase risk
of suicide in multiple studies. Harris and Barraclough (172), for
example, analyzed data from 38 studies that had follow-up periods
of up to 60 years. Acknowledging that some heterogeneity
in the diagnosis of schizophrenia across studies was likely as a
result of changes in diagnostic criteria, the authors noted 1,176
suicides among more than 30,000 patients with schizophrenia, yielding
an SMR for suicide in schizophrenia of 8.45. Baxter and Appleby
(188), in a case registry study of long-term suicide risk in the
United Kingdom, found an even higher 14-fold increase in rate ratios
for suicide among individuals with schizophrenia. In contrast, using
cohort-based curve-fitting techniques and data from 29 studies of
mortality in schizophrenia, Inskip et al. (94) estimated the lifetime
risk for suicide as 4%.
In addition to assessing suicide rates among patients with
schizophrenia, longitudinal follow-up studies have also examined
factors associated with increased risk of suicide. Black et al.
(98) found that suicide occurred in 14 of 688 schizophrenia patients
(2%) who were admitted to an Iowa psychiatric hospital
over a 10-year period, with the majority of deaths occurring within
2 years of hospital discharge. Although women were found to be at
relatively greater risk, the numbers of suicides significantly exceeded
expected rates for both male and female patients. Nyman and Jonsson
(101) found that suicide occurred in 10 of 110 (9%) young
patients with schizophrenia who were hospitalized between 1964 and
1967 and followed for up to 17 years. In this group, suicide was
associated with a more chronic course as well as with social and
financial dependency. Dingman and McGlashan (103) longitudinally
followed 163 Chestnut Lodge patients with a diagnosis of schizophrenia
and noted that the 13 patients who died by suicide were predominantly
male and had a later onset of illness, less chronic illness, better
premorbid functioning, and a greater ability for abstract and conceptual
thinking. At a later follow-up (mean=19 years), 6.4% of
the Chestnut Lodge sample had died by suicide, and this group had
exhibited fewer negative symptoms but more severe delusions and
suspiciousness at index admission than those who did not die by
suicide (93). A group of young psychotic patients who had not exhibited
a chronic course was followed after discharge from an index hospitalization
by Westermeyer et al. (83), who found that 36 patients died by suicide
and 550 did not. Suicide occurred in about 9% of individuals
with schizophrenia and was more likely during the early years of
their illness, particularly within 6 years of initial hospitalization.
At greater risk for suicide were unmarried white male patients with
chronic symptoms, relatively high IQs, and a gradual onset of illness.
De Hert et al. (89) studied outcomes for 870 patients (536
men and 334 women) with schizophrenia (87%) or schizoaffective
disorder (13%) after a mean duration of follow-up of 11.4
years. Sixty-three individuals died by suicide, yielding a suicide
rate of 635 per 100,000 per year and an SMR for suicide of 39.7.
The frequency of suicide in men was twice that in women, although
the SMR and the age at the time of suicide did not differ significantly
between the sexes. Of the suicides, 33 (52.4%) occurred while
the patient was hospitalized (although only nine actually took place
in the hospital) and 12 (19.1%) occurred during the first
6 months after discharge. When the patients who died by suicide were
compared with an age- and sex-matched group of 63 patients from
the remaining sample, a number of differences between the groups
were observed. Those who died by suicide were more likely to have
a family history of suicide, had had more and shorter hospitalizations
and more past suicide attempts, and were more likely to have used
a highly lethal method in prior suicide attempts. They also had
higher total WAIS IQ scores and were more likely to have been psychotic
or depressed or to have suffered a major loss in the 6 months
before death or follow-up. Compared with control subjects, the patients
who died by suicide were also less likely to have received community-based care
and were less likely to have had a useful daily activity, remission
of symptoms, or an early onset of prominent negative symptoms.
Among individuals with schizophrenia who die by suicide, a
number of demographic factors seem to be present more often than
in living control subjects. In a cohort of 9,156 patients with schizophrenia,
Rossau and Mortensen (95) individually matched 10 control subjects
to each of 508 individuals who were admitted to Danish hospitals
between 1970 and 1987 and who later died by suicide. They found
suicide risk to be particularly high during the first 5 days after
discharge, with some excess suicides during temporary hospital leaves.
Increases in risk were also associated with multiple psychiatric
admissions during the previous year, previous suicide attempts,
previous diagnosis of depression, male sex, and previous admissions
to general hospitals for physical disorders. Breier and Astrachan
(102) compared 20 schizophrenia patients who died by suicide with a
randomly selected sex-matched group of nonsuicidal schizophrenia
patients and a group of persons without schizophrenia who died by
suicide. Patients with schizophrenia who died by suicide were more
likely to be men and tended to be young, white, and never married.
In contrast to the persons without schizophrenia who died by suicide,
the schizophrenia patients who died by suicide tended not to show
a temporal relationship of suicide with suicide attempts or stressful
life events.
Among individuals who died by suicide, comparisons have also
been made between those with schizophrenia and those with other
diagnoses. Heila et al. (100) used psychological autopsy data for 1,397
individuals who died by suicide over a 1-year period in Finland
and compared the 92 individuals with schizophrenia (7%)
to the remainder of the sample. They found that suicide occurred
at any point during the course of schizophrenia and over a large
age range. In addition, among the individuals with schizophrenia,
71% had a history of suicide attempts, and, particularly
in women, active illness and depressive symptoms were often observed
immediately before the suicide. Significant life events, however,
were seen less often before suicide in individuals with schizophrenia
than in those with other diagnoses (46% and 83%,
respectively).
Other studies have found suicidal ideation and suicide attempts
to be common among individuals with schizophrenia. For example,
in the Chestnut Lodge sample, over an average of 19 years of follow-up,
40% of the patients with schizophrenia spectrum disorders
reported suicidal ideation since their initial hospitalization,
and 23% reported at least one suicide attempt (93). Radomsky
et al. (80) evaluated lifetime rates of suicidal behavior among
1,048 consecutively admitted psychiatric inpatients with
DSM-III-R psychotic disorders. Of the 454 individuals with a diagnosis
of schizophrenia, 27.3% reported at least one lifetime
suicide attempt, with an additional 26.4% reporting suicidal
ideation only. For the 159 patients with schizoaffective disorder,
42.8% and 27% reported suicide attempts and suicidal
ideation, respectively. Roy et al. (117) found that 55% of
a series of 127 consecutively admitted patients with chronic schizophrenia
had previously made a suicide attempt. Harkavy-Friedman et al. (108),
in a sample of 104 individuals with schizophrenia or schizoaffective
disorder, found that 33% had made a suicide attempt, with
60% of those reporting multiple attempts. Attempts were
often medically serious, requiring medical inpatient care in 57% of cases
and emergency medical evaluation in an additional 11%,
and were associated with strong suicidal intent (in the 76% of
patients for whom this information was available). As with suicide
in schizophrenia, initial suicide attempts tended to occur early
during the course of the illness.
A number of specific factors appear to increase the likelihood
of a suicide attempt among individuals with schizophrenia. For example,
in the study by Roy et al. (117), those who had attempted suicide
had significantly more psychiatric admissions and were more likely
to have experienced a major depressive episode or received antidepressant
treatment, compared with those who had not attempted suicide. Young
et al. (704), in a longitudinal study of 96 individuals with recent-onset schizophrenia
who were followed for a 1-year period, noted that depression was
moderately correlated with concurrent suicidality but was not independently
associated with future suicidality, whereas the presence of suicidal
ideation even at low levels increased the risk for significant suicidal ideation
or a suicide attempt during the subsequent 3 months. In
their sample, Harkavy-Friedman et al. (108) found that suicide attempts
were reported to be precipitated by depression (27%), loss
of a significant other or other stressful life event (24%),
being bothered by psychotic symptoms (11%), and responding
to command hallucinations (4%). In a subsequent study of
100 individuals with schizophrenia, Harkavy-Friedman et al. (106)
found that 8% of suicide attempts were associated with command
auditory hallucinations for suicide and that individuals with previous
suicide attempts were at particularly increased risk. In a prospective
study of 333 patients with chronic schizophrenia (705), multivariate
analysis suggested that current and lifetime suicide attempts and
suicidal ideation were associated with hopelessness and possibly
with greater levels of insight or higher cognitive functioning.
Increased insight, specifically awareness of delusions and negative
symptoms, has also been noted in individuals with schizophrenia
who experience recurrent suicidal thoughts and behaviors (706).
In summary, an increase in the risks of suicide and suicide
attempts is seen in individuals with schizophrenia and should be
taken into consideration in the assessment and treatment planning process.
Additional factors that modify risk include the duration of illness,
the patient's insight into the illness's implications,
the patient's history of treatment, and the presence of
comorbid diagnoses or specific psychiatric symptoms, such as depression,
hopelessness, or negative symptoms. As with mood disorders, however,
increasing evidence also suggests that the risk of suicidal behaviors
among individuals with schizophrenia can be modifiable with treatment
(see Section VI.D, "Somatic Therapies").
Data on lifetime rates of suicide among patients with anxiety
disorders are limited but suggest that these diagnoses are associated
with an increase in suicide risk. At the same time, it is not clear whether
anxiety disorders represent an independent risk factor for suicide
or whether this increased risk is attributable to the presence of depressive
disorders or substance use disorders, which commonly co-occur with
anxiety disorders.
Among broadly defined groups of individuals with anxiety disorders,
increased rates of suicide have been seen in several studies. Khan
et al. (118) used the U.S. Food and Drug Administration (FDA) database
to assess the risk of suicide among patients who were participating
in recent clinical trials of antianxiety medications and had diagnoses
of panic disorder, social phobia, generalized anxiety disorder,
posttraumatic stress disorder, or obsessive-compulsive disorder.
Among the 20,076 patients, 12 died by suicide, yielding a suicide
risk among patients with anxiety disorders of 193 per 100,000 patients,
or at least 10-fold higher than that in the general population.
This finding is particularly striking since the patients were receiving
treatment and since current suicidality is generally an exclusion
criterion for clinical trials. Allgulander (119) also noted an increased
risk of suicide in individuals with anxiety disorders. Data on 9,912
patients with anxiety neurosis in the Swedish National Psychiatric
Case Register between 1973 and 1983 yielded SMRs for suicide before age
45 of 6.7 and 4.9 for men and women, respectively. Suicide risk
was highest within 3 months of discharge and was two- to threefold
less than the risk in individuals with depressive neurosis.
Several studies have examined characteristics of patients
with panic attacks or panic disorder who have died by suicide. Henriksson
et al. (707) used data on suicides in Finland in a 1-year period
to examine the relationship between panic disorder and suicide.
All of the 17 persons with a current diagnosis of panic disorder
who died by suicide1.22% of the 1,397 suicides
in Finland in the 1-year periodalso had another axis I
disorder, most often major depression. A substance use disorder was
found in one-half of these individuals, with almost one-half of
those persons also receiving an axis II diagnosis. These results
are in accord with those of a study by Barraclough et al. (65),
which found a principal diagnosis of either alcoholism or depression
in virtually all persons who died by suicide and who had had a panic
attack in the week before death.
Two smaller follow-up studies of patients with panic disorder
yielded similar conclusions. Noyes et al. (122) found that 4% (three
of 74) of patients with panic disorder followed up after 7 years
had died by suicide, with an additional 7% (five of 74)
having made a serious suicide attempt. Comorbid diagnoses, particularly
major depression and axis II disorders, were more likely to be present
in those who died by suicide and in serious suicide attempters.
Coryell et al. (123) found that 35 years after an index admission,
approximately 20% of 113 patients with panic disorder had
died by suicide and that alcoholism and secondary depression may
have had a role in those deaths.
Rates of suicidal ideation and suicide attempts are also increased
in individuals with anxiety disorders, but again, comorbid diagnoses
may play a role in mediating this effect. In a random sample of
18,011 adults from five U.S. communities derived from the ECA study,
Weissman et al. (125) found that the presence of suicidal ideation
and suicide attempts varied. Levels were highest among subjects
with a lifetime diagnosis of panic disorder, followed by those who
had panic attacks but not panic disorder and those with other DSM-III
disorders but not panic attacks or panic disorder; lower levels
were found in individuals with no prior panic attacks or DSM-III
diagnoses. Weissman et al. also found that 20% of the subjects
with panic disorder and 12% of those with panic attacks
had made suicide attempts. Furthermore, this increase in risk was
not solely attributable to comorbid diagnoses, since the
lifetime rate of suicide attempts for persons with uncomplicated
panic disorder was consistently higher than that for persons with
no psychiatric disorder (7% and 1%, respectively) (708).
This conclusion contrasted with the findings of Hornig and McNally
(137), who reanalyzed the ECA data with the effects of comorbid
disorders and sociodemographic variables controlled in the aggregate
rather than singly. Using both stepwise and backward logistic regression
analyses, they did not find panic disorder to be associated with
a significant increase in risk for suicide attempts beyond that
predicted by the presence of other disorders.
Other investigators have assessed other populations to determine
whether panic attacks or panic disorder is associated
with increases in suicidal behaviors. Pilowsky et al. (130), in
a study of 1,580 adolescents in an urban public school system, found
that suicidal ideation was three times more likely and a history
of suicide attempts twice as likely in individuals with panic attacks,
even after the effects of demographic factors, major depression,
and substance use were controlled. Fleet et al. (136) assessed 441
consecutive patients who presented to an emergency department with
chest pain and who underwent a structured psychiatric interview.
Of the total sample, 108 (25%) met the DSM-III-R criteria
for panic disorder. The investigators found that more of those with
panic disorder had experienced suicidal ideation during the preceding
week than of those without panic disorder (25% and 5%,
respectively), even after controlling for the effect of coexisting
major depression. In addition, of the 44 patients (10% of
the sample) who had experienced suicidal ideation during the preceding week,
60% met the DSM-III-R criteria for panic disorder (709).
Thus, in both of these populations, panic attacks or panic disorder
was a significant risk factor for suicidal ideation or suicide attempts, independent
of comorbid disorders.
Other studies have assessed psychiatric outpatients with panic
disorder and have demonstrated substantial variability in its effect
on suicidality. Cox et al. (124), for example, used the suicide questions
from the ECA study to assess 106 patients with panic disorder and
found that 31% of the patients reported suicidal ideation
and 18% reported a history of suicide attempts. Very few individuals
with suicidal ideation reported actual suicide attempts within the
preceding year. However, when suicide attempts did occur, they were
predominantly in the context of depressed mood. In a sample of 100
outpatients with panic disorder, Lepine et al. (129) found that
42% had a prior suicide attempt. Suicide attempters were
more likely to be female or unmarried, and 88% of the patients
met the DSM-III-R criteria for at least one additional diagnosis,
predominantly major depressive disorder (52%) or substance
use disorder (31%). Warshaw et al. (127) followed 498 patients
with panic disorder and found a 6% risk of suicidal behaviors
over a 5-year period. Being married or having children were protective
factors, whereas mood disorders, substance use, eating disorders,
personality disorders, female sex, and a prior history of suicide
attempts were associated with increased risk. In the absence of
other risk factors, the risk of a suicide attempt in persons with panic
disorder was minimal. King et al. (126) studied 346 depressed outpatients
and found a significant difference in the frequency of suicide attempts
in those with a history of panic attacks compared with those without
such a history (26.9% and 16.8%, respectively).
Paradoxically, however, depressed patients with a history of infrequent
panic attacks had a higher incidence of suicide attempts than those
with panic disorder (32.3% and 21.5%, respectively).
Friedman et al. (710) assessed 293 patients with panic disorder,
of whom 59 had comorbid borderline personality disorder. A past
history of suicide attempts was reported by 25% of the
patients with comorbid borderline personality disorder and by 2% of
those without that comorbidity. In contrast, Beck et al. (128) found
that none of the 73 patients with primary panic disorder in a study
of 900 consecutive psychiatric outpatients reported having made
a prior suicide attempt.
Other anxiety disorders, although less well studied, may also
influence suicide attempts or suicidal ideation. For example, in
recent clinical trials of new antianxiety medications that included
patients with a broad range of diagnoses, the risk of suicide attempts
was increased relative to the general population, with attempts
occurring in 28 of 20,076 patients, for an annualized risk of 1,350
per 100,000 patients (118). Cox et al. (124) found that of 41 outpatients
with a diagnosis of social phobia, 14 (34%) had experienced
suicidal ideation and two (5%) had made a suicide attempt
within the prior year, although five (12%) had at least
one lifetime suicide attempt. Oquendo et al. (131) assessed 156
inpatients with a diagnosis of major depressive episode and found
that those with comorbid posttraumatic stress disorder were more
likely to have attempted suicide, a finding that was more prominent
in women than in men and that was independent of the presence of
borderline personality disorder. Schaffer et al. (132) retrospectively
reviewed the assessments of 533 patients with major depression and
found that suicidal ideation was present in 57.8%. Suicidal
ideation was more likely to be present in the 43.2% of
the sample that had a lifetime anxiety disorder, and this association
was independent of either age or severity of depressive symptoms.
In contrast, in a study of 272 inpatients with at least one major
depressive episode, Placidi et al. (220) found that rates of panic
disorder did not differ between the 143 patients who had attempted
suicide and the 129 patients who had not. In fact, agitation, psychic
anxiety, and hypochondriasis were more severe in the nonattempter
group, and these effects were independent of severity of aggression
and impulsivity. However, rates of comorbid borderline personality
disorder were much greater in those who attempted suicide, which may
have contributed to these findings.
Even subsyndromal anxiety symptoms may contribute to an increase
in risk. For example, Marshall et al. (135) found that rates of
suicidal ideation increased linearly and significantly with an increasing
number of subthreshold symptoms of posttraumatic stress disorder.
They reported that for the 2,608 of 9,358 individuals who were screened
in 1997 as part of National Anxiety Disorders Screening Day and
who reported at least one symptom of posttraumatic stress disorder
of at least 1 month's duration, the risk of suicidal ideation
was increased, even after controlling for the effect of comorbid
major depressive disorder.
Anxiety disorders may be overrepresented among individuals
with suicidal ideation or suicide attempts. Pirkis et al. (383)
analyzed data from 10,641 respondents in the Australian National
Survey of Mental Health and Wellbeing and found that the relative
risk of anxiety disorder was increased 3.5-fold in individuals with
suicidal ideation in the prior year and increased sevenfold in those
with a suicide attempt in the prior year.
Thus, available evidence suggests that anxiety disorders,
particularly panic disorder, may be associated with increased rates
of suicidal ideation, suicide attempts, and suicide. It remains
unclear whether panic attacks and panic disorder represent independent
risk factors for suicide or whether elevations in suicidality associated
with these disorders are simply a reflection of comorbidity with other
disorders such as depression, substance use disorders, or personality
disorders. Nonetheless, individuals with anxiety disorders warrant
explicit evaluation and follow-up for comorbid diagnoses and for
suicide risk. Psychiatrists should also be alert for masked anxiety
symptoms and for anxiety disorders that are misdiagnosed as physical illnesses.
Studies point to eating disorders in general as a risk factor
for death and as a likely risk factor for suicide. For example,
Harris and Barraclough (64) calculated SMRs for suicide using data
from 15 studies and found a 23.1-fold increase in risk in patients
with eating disorders. Herzog et al. (138), in an 11-year longitudinal
study of 246 women with eating disorders, noted a crude mortality
rate of 5.1% and an SMR for death by any cause of 9.6.
Three of the women died by suicide, yielding a significantly elevated
SMR for suicide of 58.1.
The risk associated with specific eating disorders is less
clear. Eckert et al. (139), in a similar longitudinal study, examined
the clinical course and outcome of anorexia nervosa in 76 severely
ill females. Although none of the deaths were attributed to suicide,
by the time of 10-year follow-up, five subjects (6.6%)
had died, yielding an almost 13-fold increase in mortality.
Coren and Hewitt (140) extracted data from all death certificates
in the United States registered with the National Center for Health
Statistics from 1986 through 1990. Of 5.5 million females who died
in that period, 571 had anorexia nervosa listed as an
underlying cause or accompanying condition of death. Of these, 1.4% died
by suicide, compared to 4.1% of a matched control sample,
suggesting that the risk of suicide in persons with anorexia nervosa
is, if anything, lower than that in control subjects. However, substantial
underreporting bias may be present, since personnel recording information
on death certificates may not recognize anorexia as a contributory
comorbid condition.
Eating disorders, particularly bulimia nervosa, have also
been associated with an increased rate of suicide attempts, and,
conversely, suicide attempters may have an increased rate
of abnormal eating behaviors. Kent et al. (141) compared 48 women
who were referred for psychiatric assessment after an act of deliberate
self-poisoning with 50 control subjects who were evaluated in a
hospital emergency department after a minor accidental injury. Even
after controlling for the effect of differences in rates of depression,
the investigators found that disordered eating behaviors were significantly
more prevalent in the self-poisoning group. Compared to the general
community, for whom surveys suggest rates of bulimia nervosa of
1%–2%, four subjects (8%) in
the self-poisoning group met the diagnostic criteria for bulimia
nervosa. Thus, awareness of eating disorders may be important in
evaluating patients after a suicide attempt.
By the same token, suicide attempts may be more likely in
women with eating disorders. Using anonymous survey data gathered
from 3,630 girls in grades 6 through 12 in the upper Midwest, Thompson
et al. (142) found that eating disturbances and aggressive behavior
were significantly associated with substance use and with attempted
suicide. In addition, adolescents reporting disturbed eating behaviors
were three times more likely to report suicidal behaviors than were
other respondents.
In summary, individuals with eating disorders may be at increased
risk for suicidal behaviors. Anorexia nervosa seems more likely
to be a potential risk factor for suicide, whereas bingeing, purging,
and bulimia may be more likely to be associated with suicide attempts.
The role of comorbid diagnoses in increasing the risk of suicidal
behaviors remains unclear. Also unclear is whether the self-imposed
morbidity and mortality associated with severe caloric restriction
or bingeing and purging should be viewed as a self-injurious or
suicidal behavior. Regardless, clinicians conducting suicide risk
assessment should be attentive to the presence of eating disorders
and especially the co-occurrence of eating disorders with other
psychiatric disorders or symptoms such as depression or deliberate
self-harm.
The relationship between ADHD and suicidal behavior is unclear,
with some but not all studies indicating an association between
the diagnosis of ADHD and suicide attempts or suicide. To identify psychiatric
risk factors for adolescent suicide, Brent et al. (145) used psychological
autopsy data to match 67 adolescents who died by suicide to community
control subjects. At the time of death, 89.6% of those
who died by suicide had a psychiatric disorder, with major depression,
bipolar disorder–mixed episode, substance use disorder,
and conduct disorder seen at increased rates relative to the rates
for the community control subjects. In contrast, the rate of ADHD
in those who died by suicide was 13.4% and did not differ
from the rate in the control subjects (145). Similarly, in a case-control study
of adolescent suicide attempters, ADHD was actually less likely
in those who attempted suicide than in the control subjects (146).
In a group of subjects between ages 17 and 28 years, Murphy
et al. (144) compared 60 subjects with ADHD, combined type, to 36
subjects with ADHD, predominantly inattentive type, and to 64 community
control subjects. A higher proportion of the group with ADHD, combined
type (15%), reported attempting suicide, compared
with the group with ADHD, predominantly inattentive type (2.8%),
and the control group (0%). Compared to the control group,
both ADHD groups had greater amounts of psychological
distress, received more prescriptions for psychiatric medication
and more types of psychiatric services, and had a higher prevalence
of alcohol/cannabis use disorders and learning disorders.
The groups did not differ in comorbidity of conduct disorder, major
depressive disorder, or anxiety disorders. Patients with the combined
type of ADHD are clinically more likely to present with distractible
and impulsive behavior, whereas patients with the predominantly inattentive
type of ADHD are more likely to present with problems of staring,
daydreaming, confusion, passivity, withdrawal, and sluggishness
or hypoactivity. These differences in clinical features may account
for the differences in the numbers of suicide attempts in the two
subgroups.
Nasser and Overholser (143) examined the lethality of suicidal
behavior in 60 hospitalized adolescent inpatients who had recently
attempted suicide. The subjects were divided into three equal groups on
the basis of the qualities of their suicidal acts (nonlethal, low-lethal,
and high-lethal). The groups did not differ significantly in terms
of hopelessness, depression, substance abuse, and self-esteem or in
diagnoses of major depression, adjustment disorder, substance abuse,
and bipolar disorder. However, the group of high-lethal attempters
included four individuals with a diagnosis of major depressive episode
and comorbid ADHD. Thus, it may be the comorbidity of ADHD with
other disorders that increases the relative lethality of suicide
attempts.
In summary, evidence for an independent association between
ADHD and risk for suicide or attempted suicide appears weak. Individuals
with ADHD, combined type, seem to be at greater risk than those
with ADHD, predominantly inattentive type, perhaps because of an
increased level of impulsivity. In addition, there may be a relationship
between ADHD and suicide risk that relates to comorbidity with conduct
disorder, substance abuse, and/or depressive disorder.
Given the frequent occurrence of ADHD in patients with other psychiatric
disorders, it is important for psychiatrists to be aware that comorbid
ADHD may augment the risk of suicidal behaviors.
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f) Alcohol use disorders
The presence of an alcohol use disorder increases suicide
risk. Estimates based on computerized curve fitting of data from
27 studies have suggested a 7% lifetime risk of suicide
in individuals with alcohol dependence (94). Other approximations
of lifetime suicide risk have ranged from 3.4% to as high
as 15% (148, 157) but vary by country and depend on the
definition of alcoholism used. In fact, the vast majority of studies
have not used the DSM-IV criteria for alcohol use disorders, making comparisons
across studies difficult. As a result, descriptions of studies in
this document will use the diagnostic terms employed by the study
authors.
Harris and Barraclough (64) used data from 32 publications,
including findings for more than 45,000 individuals with follow-up
periods for up to 30 years, to calculate an SMR for suicide of 5.86 among
persons with alcohol abuse or dependence. The overall suicide rate
for women with alcohol abuse or dependence was about 20 times the
expected rate, whereas the rate for men was only about four times
the expected rate. Beck et al. (227) also found a risk of suicide
in alcoholics that was about fivefold greater than in nonalcoholics
in a sample of 413 patients hospitalized for a suicide attempt and
prospectively followed for 5–10 years. They also noted
that the timing of suicides was spread throughout the follow-up,
with no particular period of increased risk.
The association between alcohol use disorders and suicide
is also demonstrated by psychological autopsy studies, which show
alcohol use disorders to be common among individuals who die by suicide.
For example, Henriksson et al. (59), in a random sample of 229 Finnish
suicide deaths during a 1-year period, found that alcohol dependence
was present in 43% of cases. In the United States, Conner
et al. (150) found that 39% of 141 individuals who died
by suicide over a 2.5-year period had had a history of alcohol use
disorder.
Significant rates of alcohol use were also seen in a sample
of youth suicides that included older adolescents. Brent et al.
(151) examined death certificates and coroners' reports
for all suicides, undetermined causes of death, and questionable
accidents for 10- to 19-year-old residents of Allegheny County,
Pennsylvania, from 1960 to 1983. Altogether, 159 definite suicides
and 38 likely suicides were noted, but the suicide rate increased
markedly over the study period, particularly among white males ages
15–19 years. During the study period there was also a 3.6-fold
increase in the percentage of suicides with detectable blood alcohol
levels (12.9% in 1968–1972, compared to 46.0% in
1978–1983). In addition, the rate of suicide by firearms
increased much faster than that by other methods (2.5-fold and 1.7-fold,
respectively), and persons who died by suicide with firearms were almost
five times more likely to have been drinking than individuals who
used other suicide methods.
A number of factors have been specifically observed with suicide
in individuals with alcohol use disorders (153). Murphy et al. (152),
in a study of 50 alcoholics who died by suicide, found that 26% had
experienced interpersonal loss within 6 weeks of their death. These
findings were comparable to those in a prior group of 31 alcoholics
who died by suicides, one-third of whom had experienced the loss
of a close interpersonal relationship within 6 weeks of the suicide.
An earlier study by Murphy and Robins (156) also found a high proportion
of recent interpersonal disruptions, as did a study of suicides
in San Diego by Rich et al. (67). To identify other factors associated
with increased risk for suicide among alcoholics, a subsequent study
by Murphy et al. (149) pooled these two similar groups of alcoholics
who died by suicide and compared them to two control samples of
white male alcoholics, one from a psychiatric patient population
and one from the ECA community-based population. Clinical features
that were significantly more frequent among those who died by suicide
than among the control subjects included current alcohol use, poor
social support, serious physical illness, unemployment, living alone,
and having made a suicidal communication. Eighty-three percent of
the alcoholics who died by suicide had four or more of the seven
risk factors.
Pirkola et al. (154) also examined factors associated with
increased likelihood of suicide among alcohol misusers. They found
that alcohol misusers who died by suicide (N=349) were
more likely to be young, male, and divorced or separated, compared
with individuals who did not misuse alcohol in the several months
preceding their suicide (N=648). Alcohol misusers were
also more likely to be intoxicated with alcohol at the time of death
or to have died from an overdose of medications. Those with alcohol
misuse had also experienced more adverse life events close to the
time of their suicide despite having better psychosocial adjustment
earlier in their lifetime. For example, alcoholics who died by suicide
had more often worked but were also more likely to be recently unemployed.
A number of studies have identified comorbid disorders as
being common among individuals with alcohol use disorders who die
by suicide. In a series of 1,312 alcoholics admitted to a Swedish psychiatric
hospital between 1949 and 1969 and followed through 1980, Berglund
(157) found that alcoholics who died by suicide had a higher rate
of depressive and dysphoric symptoms than alcoholics who died of
other causes or who were alive at the end of the follow-up period.
Murphy et al. (152) also found that concurrent depression was present
in most but not all of their sample of alcoholics who died by suicide,
suggesting that depression was neither a necessary nor a sufficient precondition
for suicide. In a later study, Murphy et al. (149) found that major
depressive episodes were significantly more frequent among alcoholics
who died by suicide than among alcoholic control subjects and also
found that 58% of the alcoholics who died by suicide had
comorbid major depression.
Shaffer et al. (159) compared 120 individuals under age 20
who died by suicide to 147 age-, sex-, and ethnicity-matched community
control subjects and found that 59% of the subjects who
died by suicide and 23% of the control subjects met the
DSM-III criteria for a psychiatric diagnosis based on information
obtained from the subject's parents. When information from
multiple informants was obtained, 91% of the subjects who
died by suicide met the criteria for a DSM-III psychiatric diagnosis. In
addition, with increasing age, there was an increased prevalence
of a psychiatric diagnosis in general and of a substance and/or
alcohol use disorder in particular. Previous suicide attempts and mood
disorders were risk factors for suicide in both male and female
subjects, whereas substance and/or alcohol abuse occurred
exclusively in males and was present in 62% of 18- to 19-year-old subjects
who died by suicide.
Even in individuals whose alcohol use disorder has remitted,
suicide risk may still be increased but is likely to be influenced
by comorbid disorders. Conner et al. (150) analyzed data
from a community sample of 141 individuals who died by suicide and
found that 39% (N=55) had a history
of alcohol misuse. Compared with those who were actively using alcohol,
those with remitted alcohol use disorders were predominantly younger
individuals with psychotic disorders or older individuals with major
depression.
In addition to being associated with an increased risk of
suicide, alcohol use disorder is associated with a greater likelihood
of suicide attempts. For example, Petronis et al. (163) analyzed
data from 13,673 participants in the ECA survey and found that active
alcoholism was associated with an 18-fold increase in the relative
odds of making a suicide attempt. Gomberg (162) compared 301 women admitted
to 21 alcohol treatment facilities to an equal number of age-matched
nonalcoholic women from the community. Alcoholic women were far
more likely to have attempted suicide (40%, compared with
8.8% of nonalcoholic women), and suicide attempts were
particularly likely among alcoholic women under age 40. Alcoholic
women who had attempted suicide were more likely to have used other
drugs, and they reported significantly more tension, explosiveness,
indecisiveness, fearfulness/anxiety, and difficulty concentrating
and getting up in the morning.
Among alcoholics, differences also have been noted between
those who attempt suicide and those who do not. Roy et al. (165),
for example, performed a case-control study to determine
the differences between alcoholic suicide attempters and alcoholic
nonattempters. Of the 298 alcoholic patients studied, 19% had
attempted suicide. Compared with the nonattempters, the attempters
were significantly more likely to be female, to be young, and to
have a lower economic status. They also were more likely to have
first- or second-degree relatives who abused alcohol, to consume
a greater amount of alcohol when drinking, and to have begun heavy
drinking and experienced the onset of alcohol-related problems at
an earlier age.
In addition, comorbid diagnoses are frequently identified
among alcoholics who attempt suicide. Roy et al. (165), for example,
found the most common comorbid psychiatric diagnoses among alcoholic
suicide attempters to be major depression, antisocial personality
disorder, substance abuse, panic disorder, and generalized anxiety
disorder. Hesselbrock et al. (166), in a sample of 321 inpatients
(231 men, 90 women) in alcoholism treatment centers, found that
suicide attempters typically had multiple psychiatric diagnoses
(e.g., depression, antisocial personality disorder, and substance
abuse) and more severe psychiatric symptoms than nonattempters.
Two-thirds of alcoholics who attempted suicide had a lifetime diagnosis
of major depressive disorder, and most reported symptoms of depression
within 2 weeks of the interview. Alcoholic suicide attempters tended
to have a parental history of alcoholism, to have begun abusing
alcohol at an early age, and to have abused other substances in
addition to alcohol.
Preuss et al. (167), using data for 3,190 alcohol-dependent
individuals from the Collaborative Study on the Genetics of Alcoholism,
found that alcohol-dependent individuals with a history of suicide
attempts were more likely to be dependant on other substances and
more likely to have other psychiatric disorders. In addition, subjects
with suicide attempts had a more severe course of alcohol dependence
and more first-degree relatives with suicide attempts. In a subsequent
study that followed 1,237 alcohol-dependent subjects over
5 years, Preuss et al. (168) found that the 56 alcohol-dependent subjects
with suicide attempts during the follow-up period were more likely
to have a diagnosis of a substance-induced psychiatric disorder
or be dependent on other drugs. Furthermore, among 371 alcohol-dependent
individuals who had made a suicide attempt and also had had an episode
of depression, the 145 individuals (39.1%) with alcohol-independent
mood disturbance had a greater number of prior suicide attempts
and were more likely to have an independent panic disorder but reported
a less severe history of alcohol dependence and were less likely
to have been drinking during their most severe attempt (169). These
findings suggest that in taking a clinical history in suicide attempters
it is useful to identify comorbid depression but also to determine
whether depressive episodes are alcohol induced or not.
That the presence of prior attempts is predictive of future
attempts also highlights a need for taking a thorough history of
past suicidal behaviors. Preuss et al. (168) followed 1,237 alcohol-dependent subjects
over 5 years and found that the 56 alcohol-dependent subjects with
suicide attempts during the follow-up period were more likely to
have made prior attempts than subjects with no suicide attempts.
Persons with comorbid major depression and alcohol use have higher
rates of suicidal symptoms than those with either alone. Cornelius
et al. (170) compared 107 patients with both major depression and
alcohol dependence to 497 nondepressed alcoholics and 5,625 nonalcoholic
patients with major depression assessed at the same psychiatric
facility using a semistructured initial evaluation form. Depressed
alcoholics had a significantly greater degree of suicidality, as
reflected by a global measure that included wishes for
death, suicidal ideation, and suicidal behaviors. They also differed
significantly from the nonalcoholic depressed patients in having
lower self-esteem and greater impulsivity and functional
impairment.
In a subsequent study, Cornelius et al. (171) found that among
psychiatrically hospitalized alcoholics with major depression, almost
40% had made a suicide attempt in the week before admission,
with 70% having made a suicide attempt at some point in
their lifetime. There was a significant association between recent
suicidal behavior and recent heavy drinking, with most subjects
also reporting drinking more heavily than usual on the day of their
suicide attempt. In addition, these suicide attempts were usually
impulsive. Suicidal ideation, however, was not increased by more
recent heavy alcohol use, suggesting that alcohol increases suicidal
attempts by increasing the likelihood of acting on suicidal ideation.
In summary, alcohol use disorders are associated with increased
risks of suicide and suicide attempts. Conversely, rates of alcohol
use disorders are elevated among those who die by suicide as well
as among suicide attempters. The common occurrence of comorbid psychiatric
symptoms and diagnoses suggests a need for thorough assessment and
treatment of such complicating factors in users of alcohol. Also,
the frequent presence of psychosocial stressors including unemployment
and interpersonal losses should also be taken into consideration
in the assessment and treatment planning process.
+
g) Other substance use disorders
As with disorders of alcohol use, other substance use disorders
may be associated with an increased risk of suicide. Harris and
Barraclough (172) noted that the SMRs for suicide varied widely
across studies and that calculations were often confounded by the
subjects' simultaneous use of multiple substances and by
the difficulties in distinguishing accidental overdoses from suicide.
Nonetheless, their meta-analysis of published literature found that
substance use disorders were associated with a substantial increase
in suicide risk. The SMRs for suicide were 14.0 for those with opioid
abuse or dependence; 20.3 for those with sedative, hypnotic, or
anxiolytic abuse or dependence; and 19.2 for individuals with mixed
substance abuse or dependence.
Among individuals with substance use disorders, suicide may
be more likely in the presence of comorbid diagnoses such as mood
disorders. For example, in a study comparing 67 adolescents who died
by suicide to 67 demographically matched community control subjects,
Brent et al. (145) found that substance abuse conferred more significant
risk when it was comorbid with affective illness than when it was
present alone (odds ratio of 17.0 and 3.3, respectively). Lesage
et al. (174) compared 75 male subjects ages 18–35 years
who died by suicide to a group of 75 demographically matched living control
subjects and found significantly greater rates of DSM-III-R psychoactive
substance dependence among the subjects who died by suicide (22.7% versus
2.7%). They also found that comorbid major depression or
borderline personality disorder was common among those with substance
dependence who died by suicide.
In psychological autopsy studies, diagnoses of substance use
disorders are particularly common among individuals under age 30
who die by suicide. For example, Fowler et al. (173) studied a subset of
128 individuals from the San Diego Suicide Study (67) who were under
30 years old and found that 53% had a diagnosis of substance
abuse. Of this group, about one-half had an additional psychiatric
diagnosis such as atypical depression, atypical psychosis, or adjustment
disorder with depression. Despite the young age of the study sample,
substance abuse was typically a chronic condition that had been
present for an average of 9 years. Abuse of multiple substances
was the norm, with marijuana, alcohol, and cocaine being the most
frequently abused substances. Other data from the San Diego Suicide
Study sample as a whole (110) showed that most substance users abused alcohol
as well as other substances, with relatively small numbers of "pure" alcoholics
or "pure" substance users. They also noted that
interpersonal conflicts or loss occurred more frequently near the
time of death for substance abusers with and without depression
than for persons with mood disorders alone.
Although the majority of persons with substance use disorders
who die by suicide are male, it is important to recognize that men
and women with substance use disorders may differ in their characteristics
and their risk for suicide. Pirkola et al. (175) used data from
a nationwide psychological autopsy study in Finland to study the
characteristics of a sample of 172 men and 57 women who died by
suicide and had a DSM-III-R diagnosis of psychoactive substance
dependence. They found that women were more likely than men to have
abused or been dependent on prescribed medication. In addition,
women were more likely than men to have a substance use disorder
preceded by a comorbid axis I disorder (45% and 18%,
respectively). Borderline personality disorder, previous suicide
attempts, and suicidal communications were more common in women
age 40 years or younger. In addition, alcohol-dependent women died
at a younger age than women with nonalcohol substance dependence
and also died at a younger age than men with either alcohol dependence
or nonalcohol substance dependence.
Available evidence suggests that suicide attempts are common
in substance users and that substance use disorders are associated
with an increased risk of suicide attempts. Borges et al. (176) used
data from the U.S. National Comorbidity Survey, a nationally representative
sample of 8,098 persons age 15–54 years that was carried
out in 1990–1992, to examine whether retrospectively reported
substance use, abuse, and dependence are predictors of the onset
of suicidal behavior. After controlling for the effects of sociodemographic
factors and comorbid psychiatric disorders, the investigators found
that subsequent suicide attempts were predicted by use of alcohol,
heroin, or inhalants. Current substance use, rather than a history
of use, increased the likelihood of suicidal behavior, with the
number of substances used being more important than the types of
substances used. In addition, among those with suicidal ideation,
current substance use, abuse, and dependence were significant risk
factors for unplanned suicide attempts.
Rossow and Lauritzen (178) assessed the self-reported prevalences
of nonfatal overdoses and suicide attempts in 2,051 individuals
who were being treated for substance abuse. Almost one-half (45.5%)
reported having had one or more life-threatening overdoses, and
nearly one-third (32.7%) reported one or more suicide attempts.
Suicide attempts were more often reported among those who had overdosed,
and the number of life-threatening overdoses and number of suicide
attempts were positively and moderately associated. Individuals
who had exhibited both life-threatening behaviors also showed higher
rates of HIV risk-taking behaviors, poor social functioning, and
use of multiple substances. Suicide attempters also had more symptoms
of depression and anxiety as measured by the Global Assessment Scale.
Thus, there is substantial covariation between suicide attempts
and drug overdoses in individuals with substance use disorders
that is also associated with other risk-taking behaviors and poor
social integration.
Individuals with substance use disorders also have an increased
likelihood of making a suicide attempt, compared to control subjects.
Beautrais et al. (177) compared 302 individuals who had made medically
serious suicide attempts to 1,028 control subjects who were randomly
selected from local electoral rolls. Overall, those who had made
a serious suicide attempt had high rates of substance use disorders
(odds ratio=2.6). Furthermore, of those with a serious
suicide attempt, 16.2% met the DSM-III-R criteria for cannabis
abuse/dependence at the time of the attempt, compared with
1.9% of the control subjects (181). Mann et al. (31), in
a study of 347 consecutive admissions to a university psychiatric
hospital, found that the 184 patients who had made a prior suicide
attempt had a greater likelihood of past substance use disorder
or alcoholism. Johnsson and Fridell (179) assessed 125 substance
abusers 5 years after hospitalization for detoxification and short-term
rehabilitation. Although seven patients were dead at the time of
follow-up, none of the deaths were from suicide. Of 92 interviewed
subjects, nearly one-half the group (45%) reported having
attempted suicide at some point in their lives, with about 50% of
that group having attempted suicide with prescribed psychotropic
drugs such as antidepressants or sedatives. Only a few of the suicide
attempts were made by using the individual's primary substance
of abuse. The most common reasons given for suicide attempts were
the loss of a person whom they loved and feelings of loneliness.
Compared to those who had never made a suicide attempt, the suicide
attempters were more likely to have had childhood psychiatric hospitalizations
or experienced loss of significant others in childhood. They also
were more likely to experience depressive moods or other psychiatric
comorbidity.
The combination of cocaine use plus alcohol use also appears
to increase the risk of suicide attempts. Cornelius et al. (711)
found that of 41 consecutively admitted depressed alcoholic inpatients, 16
had made a suicide attempt and 10 had used cocaine during the week
before their hospitalization. The proportion of patients making
a suicide attempt in the week before admission was greater in those who
had used cocaine than in those who had not (70% and 32%,
respectively). Suicidal ideation was also more prevalent in the
depressed alcoholics who also used cocaine. Roy (180) studied the
characteristics of cocaine-dependent patients in a substance abuse
treatment center and compared the 130 individuals who had never
attempted suicide with the 84 individuals who had made prior suicide
attempts (a mean of 2.1 prior attempts). Compared with nonattempters,
attempters were more likely to be female and to have a lifetime
history of alcohol dependence (58.3%, compared with 34.6% for
nonattempters) and a family history of suicidal behavior (25%,
compared with 5.4% for nonattempters). Attempters also
had significantly higher childhood trauma scores for emotional abuse,
physical abuse, sexual abuse, emotional neglect, and physical neglect
than the nonattempters; however, these scores were not corrected
for the differences in the gender ratios in the two groups. Thus,
suicide attempts are common among individuals seeking treatment
for cocaine dependence, and factors that seem to augment risk are
similar to those for other groups of suicide attempters.
In summary, studies indicate that substance use is a significant
risk factor for suicide attempts and suicide. This is particularly
true in younger individuals, leading some researchers to hypothesize
that increasing suicide rates among youths may be related to increasing
rates of substance use. Individuals with chronic substance use disorders,
those who have experienced life-threatening nonsuicidal overdoses,
and those who abuse multiple substances, including alcohol, may
be at even greater risk. Moreover, substance use disorders may complicate
mood disorders (182), increasing susceptibility to treatment-resistant
illness and psychological impairment, and on that basis may contribute
to an elevated risk for suicide and for suicide attempts. As a result,
it is important to evaluate individuals with suicidality in the
context of substance use for the presence of comorbid mood disorders
as well as other comorbid psychiatric diagnoses. The evaluation
should also be aimed toward identifying patterns of recent substance
use and psychosocial factors such as recent interpersonal loss or
history of childhood trauma that may also affect the likelihood
of suicidal behaviors among substance users.
+
h) Personality disorders
Although personality disorders are often comorbid with substance
use disorders and with other psychiatric diagnoses, they also appear
to confer an independent risk for suicide. In addition, among individuals
with personality disorders, the rate of suicide may be equivalent
to rates in individuals with other major psychiatric syndromes.
For example, in a meta-analysis of 14 case-control samples and nine
longitudinal samples of patients with personality disorders, Linehan
et al. (184) found rates of suicide that were between 4% and
8%. For patients with borderline personality disorder,
studies have shown suicide rates ranging from 3% to 9% (183).
Harris and Barraclough (64) also found suicide risk to be increased,
calculating an SMR for suicide of 7.08 among individuals with personality
disorder. However, the majority of patients included in their analysis
were male and from a Veterans Administration study, raising questions
about the representativeness of the population. Baxter and Appleby
(188), in a large case registry study of long-term suicide risk
in the United Kingdom, found even higher risks for suicide among
individuals with personality disorder diagnoses, with a 12.8-fold
elevation of risk in men and a 20.9-fold elevation of risk in women
with personality disorders.
In a longitudinal follow-up study of individuals with personality
disorders, Stone et al. (185) found that 18 of the 196 patients
who were able to be located had died by suicide by 16.5 years. Compared to
a suicide rate of 8.5% for the borderline personality group
as a whole, those with alcohol problems had a twofold increase in
the rate (19%), with a 38% rate of suicide among
women who had a combination of alcoholism, major affective disorder,
and borderline personality disorder. Other factors that appeared
to contribute to suicide in individuals with borderline personality
disorder were continuing alcohol abuse, impulsivity, and a history
of parental brutality, specifically sexual molestation.
Psychological autopsy studies also show significant rates
of personality disorder diagnoses among individuals who die by suicide.
Duberstein and Conwell (186) reviewed case-based and cohort studies on
suicide in individuals with personality disorders and found that
approximately 30%–40% of suicides occur
in individuals with personality disorders, with increased risk conferred
by the presence of borderline, antisocial, and possibly avoidant
and schizoid personality disorder diagnoses.
In a random sample of all persons who died by suicide in Finland
within a 1-year period, Isometsa et al. (187) found that 29% of
the subjects (N=67) had an axis II disorder. All individuals
with a personality disorder also had at least one axis I diagnosis,
which in 95% included a depressive syndrome, a substance
use disorder, or both. Individuals with cluster B personality disorders
were more likely to have substance use disorders and to have had
a previous suicide attempt and were less likely to have had a health
care contact during their final 3 months of life. In the same group
of subjects, Heikkinen et al. (190) examined data on recent life
events for 56 subjects with personality disorder who died
by suicide and matched those subjects to control subjects who did
not have a personality disorder diagnosis. Those with a personality
disorder were more likely to have experienced one or more stressful
life events in the last 3 months of life as well as in the week
preceding the suicide. Specifically, of those with a personality
disorder, 70% had a significant event in the week before
suicide, with job problems, family discord, unemployment, and financial
difficulty reported most commonly. Thus, these findings suggest
that individuals with personality disorders who die from suicide
have high rates of comorbid depression and substance use as well
as high rates of significant life stressors that precede suicide.
The increased risk of suicide with personality disorders seems
to be a particular factor that contributes to risk in young adults.
Lesage et al. (174) compared 75 young men who died by suicide to
a demographically matched group of men in the community and found
that the 6-month prevalence of borderline personality disorder was
substantially increased among those who died by suicide (28.0% versus
4.0%). In a study of adolescents and young adults who had
been admitted to a regional poisoning treatment center because of
deliberate self-poisoning or self-injury, Hawton et al. (384) compared
62 individuals who died by suicide or possible suicide to 124 matched
control subjects and found that an increased risk of death was associated
with the presence of a personality disorder (odds ratio=2.1).
Suicide attempts may also be more likely to occur in individuals
with personality disorders than in those with other diagnoses. In
a review of the topic, Linehan et al. (184) noted that suicide attempts are
estimated to occur in 40%–90% of individuals
with personality disorders. Soloff et al. (193) examined data for
84 patients who met the DSM-III-R criteria for borderline personality
disorder and found that 61 patients (72.6%) had a lifetime
history of suicide attempts, with an average of more than
three attempts per patient. Risk factors for suicide attempts in
patients with borderline personality disorder included older age,
prior suicide attempts, antisocial personality, impulsive actions, and
a depressed mood, but not comorbid mood disorder or substance use
disorder. Ahrens and Haug (194), in a case-control study of 226
patients with a personality disorder who were admitted to a psychiatric
hospital, found that patients with a personality disorder (including,
but not limited to, borderline personality disorder) were more likely
than other hospitalized patients to have had a suicide attempt immediately
before admission, with persistent clinically relevant suicidal behavior within
the first 24 hours after admission (39% versus 24%).
Furthermore, in patients with a personality disorder, suicidality
was not related to the presence of a specific mood disorder,
since only 3% of the patients with personality disorder
met the criteria for a major affective syndrome. However, the rates
of reported suicide attempts in individuals with personality disorder
diagnoses varied with the treatment setting. Pirkis et al. (198),
in a study of suicide attempts by psychiatric patients under active
treatment, observed a rate of suicide attempts in acute inpatients
that was 10-fold greater than those for individuals in community-based
and for individuals in long-stay inpatient care (22.7 attempts per
1,000 episode-days, compared with 2.3 and 2.1 attempts per 1,000
episode-days, respectively).
Conversely, among individuals who attempt suicide, personality
disorders are commonly observed. Mann et al. (31), in a study of
347 consecutive patients who were admitted to a university psychiatric
hospital, found that comorbid borderline personality disorder was
more common among the 184 patients who had attempted suicide than
among those with no prior suicide attempts. Beautrais et al. (177)
compared 302 consecutive individuals who made serious suicide attempts
with 1,028 randomly selected comparison subjects. Multiple logistic
regression showed that those who made suicide attempts had a high
rate of conduct disorder or antisocial personality disorder (odds
ratio=3.7, 95% confidence interval=2.1–6.5).
Thus, both borderline personality disorder and antisocial personality
disorder appear to occur more frequently among suicide attempters.
In a study of consecutive patients who had attempted suicide, Suominen
et al. (191) compared 65 patients who did not have a personality
disorder diagnosis to 46 patients who received a diagnosis of personality disorder.
Of those with a diagnosis, 74% had a cluster B personality
disorder and 46% had a diagnosis of borderline personality
disorder. Individuals with a personality disorder were more likely
to have attempted suicide in the past (78%, compared to
57% of those without a personality disorder diagnosis)
and were more likely to have had psychiatric treatment in their
lifetime (85% versus 57%); however, those with
and without personality disorders did not differ in their degree
of intent, hopelessness, somatic severity, or impulsiveness. Personality
disorders were associated with a high degree of comorbidity, with
comorbid alcohol dependence being particularly common and associated with
greater difficulty in pursuing follow-up.
A number of additional factors may act as contributors to
risk for suicide attempts among individuals with personality disorders.
Brodsky et al. (196) analyzed data for 214 inpatients with a diagnosis
of borderline personality disorder according to a structured clinical
interview and examined the relationship between the specific DSM-IV
criteria for borderline personality disorder and measures of suicidal
behavior. After excluding self-destructive behavior and controlling
for the effects of lifetime diagnoses of depressive disorder and
substance abuse, they found that impulsivity was the only characteristic
of borderline personality disorder that was associated with a higher number
of suicide attempts. In addition, the number of previous suicide
attempts was associated with having a history of substance abuse.
Comorbid mood disorders are also common among suicide attempters
with personality disorder diagnoses. For example, Van Gastel et
al. (192), in a study of 338 depressed psychiatric inpatients, found
significantly more suicide attempts and more suicidal ideation among
those with a comorbid personality disorder diagnosis than among
depressed inpatients without a personality disorder. In addition,
Oquendo et al. (131) found that among 156 inpatients with a diagnosis
of a major depressive episode, having a history of suicide attempts
was independently related to the presence of a cluster B personality
disorder and to PTSD.
Corbitt et al. (195) also examined the effects of comorbid
borderline personality disorder in 102 individuals with mood disorders
and found that the 30 patients with major depressive disorder and comorbid
borderline personality disorder were just as likely to have made
a highly lethal suicide attempt as the 72 patients with major depressive
disorder alone. However, those with comorbid borderline personality
disorder were more likely to have a history of multiple serious
suicide attempts, and past suicidal behavior was better predicted
by the number of personality disorder symptoms than by the number
of depressive symptoms. Thus, they suggested that the severity as
well as the presence of comorbid cluster B personality disorder
symptoms should be ascertained in assessing the risk of suicide
attempts in patients with major depressive disorder.
Soloff et al. (197) compared the characteristics of suicide
attempts in 77 inpatients with major depressive episodes to suicide
attempts in 81 patients with borderline personality disorder, 49
of whom had a concomitant major depressive episode. Compared to
patients with borderline personality disorder alone, all of the
depressed patients had more severe observer-rated depression and
lower levels of functioning. Patients with borderline personality
disorder had higher rates of impulsivity, regardless of whether
depression was also present. However, the diagnostic groups did
not differ in their subjective intent to die, their degree of objective
planning for death, the violence of the suicide method, or the degree
of physical damage in the attempt as measured by the Beck Suicide
Intent Scale.
In summary, individuals with personality disorders, and particularly
those with a diagnosis of borderline personality disorder or antisocial
personality disorder, have increased risks for suicide and for suicide
attempts. These risks appear to be further augmented by the presence
of comorbid disorders such as major depression, PTSD, and substance
use disorders. The severity of symptoms such as impulsivity may
also play a role in increasing risk, suggesting that such factors
should be identified and addressed in the assessment and treatment
of individuals with personality disorders.
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3. Specific psychiatric symptoms
Anxiety has been suggested to increase the risk of suicide
even when a specific anxiety disorder is not present. In a review
of 46 cohort or case-control studies that used standardized or structured assessments
of psychological dimensions to assess psychological vulnerability
to suicide, Conner et al. (217) noted anxiety to be one of five
constructs that is consistently associated with suicide. Busch et
al. (218) reviewed the charts of 76 patients who died by suicide
while in the hospital or immediately after discharge and
found that 79% (N=60) met the criteria for severe
or extreme anxiety and/or agitation according to Schedule
for Affective Disorders and Schizophrenia ratings. In addition, Fawcett
et al. (79), in a study of 954 psychiatric patients with major affective
disorders, found that panic attacks and severe psychic anxiety were
factors associated with suicide within 1 year of index evaluation.
In these studies, the anxiety levels associated with suicide often
took the form of anxious ruminations, panic attacks, or agitation
and were in the severe range (i.e., severe anxiety most of the time).
With respect to the effect of anxiety on the risk of suicide
attempts, the findings are more mixed. For example, Hall et al.
(212) studied the characteristics of 100 patients who made a severe
suicide attempt and found that severe anxiety and panic attacks
were among the factors that were associated with the attempt. However,
Placidi et al. (220), in a study of 272 inpatients with at least
one major depressive episode, found that agitation and psychic anxiety
were more severe in those who had not reported making a past suicide
attempt.
Thus, although the relationship between anxiety and suicide
attempts is unclear, and specific measures of anxiety have not been
found to be predictive of suicide (78), severe anxiety does seem to
increase suicide risk at least in some subgroups of patients. In
particular, psychic anxiety, which may not be obvious to the clinician,
should be specifically assessed, since such symptoms can respond rapidly
to aggressive short-term treatment with benzodiazepines, second-generation
antipsychotic medications, and possibly anticonvulsant medications
(109).
Hopelessness has been consistently identified as a factor
associated with an increased risk of suicide, independent of diagnosis
(217). Many studies that have assessed hopelessness have used the Beck
Hopelessness Scale (712), which is described further in Section
VI.B.1, "Rating Scales". For example,
Beck et al. (222) followed 207 patients who were hospitalized for
suicidal ideation but who had not made a recent suicide attempt
to identify predictors of later suicide. After a follow-up period
of 5–10 years, 14 individuals (6.9%) had died
by suicide. Although a score of 10 or more on the Beck Hopelessness
Scale correctly identified 91% of the patients who eventually
died by suicide, there was significant overidentification of at-risk
patients, with a false positive rate of 88%. The group
who died by suicide also had a higher mean score on clinicians' ratings
of hopelessness (223).
A later longitudinal study that included 1,958 consecutive
psychiatric outpatients examined whether the level of hopelessness
at intake could predict eventual suicide (221). In this patient population,
those with a suicide death scored significantly higher on both the
Beck Hopelessness Scale and the Beck Depression Inventory. Although
a Beck Hopelessness Scale score of 10 or more was associated with
an 11-fold increase in the likelihood of suicide, the specificity
was again low. Since a high level of hopelessness is common in psychiatric
patients, applying this Beck Hopelessness Scale cutoff to a larger
population would identify 100 patients as being at risk for every
one or two eventual suicides (713).
In a subsequent study that included an expanded sample of
6,891 psychiatric outpatients seen between 1975 and 1995 and followed
for up to 20 years (with a median length of follow-up of 10 years),
Brown et al. (78) used survival analysis to identify factors associated
with increased risk for suicide. Along with higher levels of suicidal
ideation and depression, hopelessness was identified as a risk factor
for suicide, with patients who scored above 8 on the Beck Hopelessness
Scale being at four times greater risk for suicide in a given year
than those with lower scores.
The effect of hopelessness on suicide risk may vary by diagnosis,
however. Fawcett et al. (79), in a longitudinal follow-up study
of 954 patients with major affective disorder, found that severe
hopelessness was one of several factors associated with an increased
risk of suicide more than 1 year after the index assessment. However,
among subjects who met the criteria for alcohol or substance abuse
at any time, those who were not pervasively hopeless had the highest
suicide risk at 5-year follow-up (226). This pattern is consistent
with the findings of Beck et al. (227), who followed 161 alcohol-abusing
patients for 7–12 years after they were hospitalized for
a suicide attempt. Comparison of the 18 individuals who died by
suicide to the remainder of the group failed to show a relationship
between suicide and either hopelessness or depression.
Hopelessness at the termination of treatment may also reflect
an increased risk for suicide. Dahlsgaard et al. (236) compared
17 cognitive therapy outpatients with mood disorder who died by suicide
with a matching group of 17 outpatients who did not. Although the
sample was small, those who died by suicide had higher levels of
hopelessness at the end of treatment and were more likely to have
ended treatment prematurely.
In addition to being a risk factor for suicide, hopelessness
is more prominent in individuals who have reported previous suicide
attempts, compared to individuals without such a history. Cohen
et al. (229), for example, found greater levels of hopelessness
in the 43 suicide attempters among 184 individuals with a first
admission for psychosis. Hall et al. (212), in a study of 100 patients
who had made severe suicide attempts, also noted feelings of hopelessness
to be associated with suicidal behavior. Among 84 inpatients with
DSM-III-R major depression, Malone et al. (230) found that the 45
individuals who had made a suicide attempt had higher subjective
ratings of hopelessness and depression severity and that these ratings
were inversely correlated with "reasons for living." In
a study comparing 148 low-income African American women who had
made a suicide attempt to 137 demographically similar women who
presented for general medical care, Kaslow et al. (230) found hopelessness
to be associated with a nearly eightfold increase in the risk of
a suicide attempt in a univariate analysis. In a multivariate logistic
regression analysis, hopelessness was independently associated with
an increased risk of suicidal behaviors. Van Gastel et al. (192)
also found that hopelessness was associated with suicidal ideation
among 338 depressed inpatients and that the presence of a comorbid
personality disorder was associated with additional increases in
suicidal ideation and suicide attempts.
Across diagnostic groups, hopelessness appears to relate to
the seriousness of suicidal ideation and intent. Soloff et al. (197)
assessed the relationship of hopelessness to suicide attempts in
inpatients with major depressive disorder (N=77) as well
as in inpatients with borderline personality disorder alone (N=32)
or in combination with major depressive disorder (N=49).
Across groups, increased hopelessness was associated with an increased
number of suicide attempts as well as an increase in the lethal
intent associated with attempts. In addition, in patients with both
disorders, higher levels of hopelessness were associated with objective
planning of suicide attempts, which would further enhance risk.
In a sample of 384 individuals who had attempted suicide, Weissman
et al. (233) found that hopelessness contributed to the severity
of suicidal intent in those with substance use disorders (N=86)
as well as in those without substance use disorders (N=298).
Other evidence suggests that the level of hopelessness cannot
be considered independently of other factors. For example, Uncapher
et al. (228) analyzed data for 60 institutionalized elderly
men and found that the relationship between hopelessness and suicidal
ideation varied with the level of depressive symptoms and was most pronounced
at moderate or higher levels of depression. Mendonca and
Holden (232) assessed 97 outpatients and found the strongest predictors
of the seriousness of current suicidal inclinations (as
measured by the Beck Scale of Suicidal Ideation) to be
hopelessness (as measured by the Beck Hopelessness Scale) and "unusual
thinking" (defined as a state of cognitive distress with
confused, disorganized thinking, including "trouble concentrating" and "mind
going blank").
Furthermore, cross-sectional assessments of hopelessness may
not necessarily be as relevant to risk as the level of hopelessness
at baseline when the individual is not depressed. Young et al. (234), in
a longitudinal study of 316 individuals, found that the baseline
level of hopelessness was a better predictor of suicide attempts
than either the level of hopelessness when depressed or the relative change
in hopelessness from baseline levels during depression.
In summary, hopelessness is well established as a psychological
dimension that is associated with an increased risk for suicide
and suicide attempts and an increased level of suicidal intent.
This relationship between hopelessness and suicidality holds true
across diagnostic groups, with the possible exception of individuals
with alcohol use disorder. These findings suggest the importance of
inquiring about current levels of hopelessness as well as inquiring
about usual levels of optimism about life and plans for the future.
They also suggest the use of interventions to reduce hopelessness as
a part of treatment.
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c) Command hallucinations
Although command hallucinations have been regarded clinically
as being associated with increased suicide risk, there is limited
evidence that addresses this question. In addition, those studies that
are available have included relatively small numbers of patients,
making it difficult to detect differences in rates of suicide or
suicide attempts between patient groups. Furthermore, in psychological
autopsy studies, it is impossible to determine whether command hallucinations
were present immediately before death or may have contributed to
suicide.
Two small studies have noted whether command hallucinations
had been present on index assessment in individuals who later died
by suicide. Breier and Astrachan (102) described 20 schizophrenia
patients who died from suicide and found that none had previously
reported hallucinated suicidal commands. In contrast, Zisook et
al. (239) found that command hallucinations, which were often violent
in content, had been reported by 46 of 106 outpatients with schizophrenia, including
the two patients who died by suicide during the study.
Other studies have tried to determine the rates at which patients
follow command hallucinations and the factors that contribute to
following or resisting such commands. For example, Junginger (241)
used a semistructured psychiatric interview and hospital chart review
to obtain information on 51 psychiatric inpatients and outpatients,
all of whom had experienced recent command hallucinations. Of these
subjects, 39.2% reported that they had followed the commands,
47.1% reported that they did not follow the commands, and
13.7% were unable to recall their response. Patients with hallucination-related
delusions and identifiable hallucinatory voices were more likely
to follow the commands than patients who were unable to identify
the voices that they heard. In a subsequent study of 93 psychiatric
inpatients who had a history of at least one command hallucination,
the most recent command hallucination reported by the subject was
rated for level of dangerousness and level of compliance with the
command (242). Of the 93 subjects, 52 (56%) reported at
least partial compliance with their most recent command hallucination,
and 40 (43%) reported full compliance. Individuals who
experienced less dangerous commands or who could identify the hallucinated
voice reported higher levels of compliance, although reported compliance
with more dangerous commands was not uncommon. Commands experienced
in the hospital were less dangerous than those experienced elsewhere,
tended to be specific to the hospital environment, and were less
likely to be followed. Based on these self-reports, the
authors concluded that psychiatric patients who experience command hallucinations
are at risk for dangerous behavior and that a patient's
ability to identify the hallucinated voice is a fairly reliable
predictor of subsequent compliance. Also, the level of dangerousness
that results from compliance with command hallucinations may be
a function of the patient's environment.
Erkwoh et al. (245) used a 24-item questionnaire to assess
the psychopathological characteristics of command hallucinations
in 31 patients with schizophrenia. Like Junginger, they found that following
the commands was predicted by recognizing the voice. In addition,
patients were more likely to comply with commands from hallucinations
that they viewed as "real" and that produced an
emotional response during the hallucination.
Kasper et al. (243) compared 27 psychotic patients with command
hallucinations to 27 patients with other hallucinations and 30 patients
with other psychotic symptoms. Although the groups did not differ
in aggressive or violent behavior or in most nonhallucinatory symptoms,
84% of the patients with command hallucinations had recently
obeyed them, even during their hospital stays. Among those with
command hallucinations, almost one-half had heard and attempted
to obey messages of self-harm during the previous month. Rogers
et al. (244), in a study of 65 forensic inpatients with psychotic
disorders, also found that a significant number of individuals (44%)
often responded to command hallucinations with unquestioning obedience.
These findings, that significant numbers of individuals comply
with at least some hallucinated commands, are in contrast with the
findings of Hellerstein et al. (240). Among 789 consecutive inpatients
admitted over a 2-year period, they found that 19.1% had
auditory hallucinations within 2 weeks of hospital admission, and,
of these, 38.4% heard commands to behave violently or self-destructively.
It is not surprising that hallucinations were more common in the
159 patients with schizophrenia, with 50.3% experiencing
auditory hallucinations and 18.2% experiencing command hallucinations.
Among 167 patients with affective disorder, rates of auditory and
command hallucinations were 13.2% and 4.2%, respectively.
The presence of auditory hallucinations was significantly associated
with use of maximal observation and seclusion. However, patients
with command hallucinations were not significantly different from
patients without command hallucinations on demographic and behavioral
variables, including suicidal ideation or behavior and assaultiveness. This
finding suggests that command hallucinations alone may not imply
a greater risk for acute, life-threatening behavior. In addition,
consistent with the findings of Goodwin et al. (714), these findings imply
that many patients are able to ignore or resist command hallucinations.
The most specific assessment of the role of command hallucinations
in suicidal behaviors is that of Harkavy-Friedman et al. (106).
They interviewed 100 individuals with schizophrenia or schizoaffective
disorder who were hospitalized on an inpatient research unit about
their experiences with command auditory hallucinations as well as
about suicide attempts. Suicide attempts were reported by 33% of
the sample, and the relative frequency of individuals with command
hallucinations did not statistically differ between those who had
and those who had not reported a suicide attempt (30% and
18%, respectively). Command hallucinations were present
in 22% of the sample as a whole, and, of these, 45% had
made at least one suicide attempt. Among individuals with command
hallucinations who had made a suicide attempt, however, 80% had
at least one attempt in response to the hallucinations. Thus, these
findings suggest that for some individuals, particularly those with
prior suicide attempts, suicidal behavior may occur in the context
of auditory command hallucinations.
In summary, study findings are inconsistent about whether
patients with command hallucinations are likely to obey them. Patients
who recognize the hallucinated voices or view them as real or benevolent
may be more likely to follow their directives. In addition, patients
with prior suicide attempts may be more likely to follow suicidal
commands. In terms of suicide risk, per se, patients with command
hallucinations may not be at greater risk than other severely psychotic
patients. However, existing studies include too few subjects to
draw strong conclusions. In addition, since some patients do seem
to act in response to auditory command hallucinations, it is important
to identify such hallucinations, assess them in the context of other
clinical features, and address them as part of the treatment planning
process.
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d) Impulsiveness and aggression
Factors such as impulsivity, hostility, and aggression may
act individually or together to increase suicide risk. For example,
many studies have provided moderately strong evidence for the roles
of impulsivity and hostility-related affects and behavior in suicide
(217, 246). In particular, impulsivity and aggression have been
shown to be associated with suicide in patients with schizophrenia
as well as in those with mood disorder. For example, De Hert et
al. (89) compared 63 patients who died by suicide and 63 control
subjects from a consecutive admission series of patients with a
diagnosis of schizophrenia, all of whom were under age 30 on admission.
In this sample, impulsive acting-out behavior was associated with
an increased likelihood of suicide (odds ratio=6.4). Among
529 patients with affective illness who were followed naturalistically
for up to 14 years and who either attempted suicide or died by suicide,
Maser et al. (247) also found that impulsivity was a core characteristic
of patients with suicidal behaviors. In fact, beyond 12 months,
higher levels of impulsivity and assertiveness were the best prospective
predictors of suicide.
Angst and Clayton (248) found a significant effect of premorbid
aggression on the risk of suicide attempts or suicide. To assess
the effect of personality traits on suicidal behaviors, they administered the
Freiberg Personality Inventory to 6,315 Swiss army conscripts. Twelve
years later, 185 of these individuals were identified as receiving
psychiatric treatment during that time period, and a record review
was conducted to establish a blind diagnosis and assess measures
of suicidality and mortality in a subgroup of 87 of those individuals.
Those who made suicide attempts or died by suicide were found to
have scored higher on aggression than control subjects. In contrast,
subjects with suicidal ideation alone scored lower on aggression,
suggesting a role for premorbid aggression in suicidal behaviors.
Multiple other studies have demonstrated increased levels
of impulsivity and aggression in individuals with a history of attempted
suicide. For example, Mann et al. (31), in a study of 347 consecutive
patients admitted to a university psychiatric hospital, found that
rates of lifetime aggression and impulsivity were greater in the
184 patients who had attempted suicide than in those without a history
of suicide attempts. Hall et al. (212) found that the recent onset
of impulsive behavior was an excellent predictor of suicidal behavior
in 100 patients who had made a severe suicide attempt. Kotler et
al. (249) compared 46 patients with PTSD to 42 non-PTSD anxiety
disorder patients and 50 healthy control subjects and found that
impulsivity was positively correlated with the risk of suicidal
behavior in the PTSD group.
Impulsivity and aggression have also been associated with
suicide attempts among patients with mood disorders. Brodsky et
al. (250), in a study of 136 depressed adult inpatients, found that
individuals with at least one prior suicide attempt had significantly
higher scores on measures of impulsivity and aggression than individuals
without reported suicide attempts. Placidi et al. (220) analyzed
data for 272 inpatients with at least one major depressive episode
and found significant increases in measures of aggression and impulsivity
in those with a history of suicide attempts, compared to those without
suicide attempts. Finally, in a study of 44 individuals with a DSM-III-R
diagnosis of bipolar disorder, Oquendo et al. (252) found that suicide
attempters were more likely to have more lifetime aggression than
nonattempters, although lifetime rates of impulsivity were not increased
among those with a prior suicide attempt.
Suicide attempters with borderline personality disorder similarly
have been reported to exhibit increased levels of aggression and
impulsivity. Soloff et al. (197) compared 32 inpatients with borderline
personality disorder alone and 77 inpatients with major depressive
episode alone to 49 patients with both diagnoses and found that
a greater number of suicide attempts was associated with a diagnosis
of borderline personality disorder or with increases in either hopelessness
or impulsive aggression. Soloff et al. (193) studied the characteristics
of 84 patients with borderline personality disorder, of whom 61
had a lifetime history of suicide attempts (72.6%), with
an average of 3.39 (SD=2.87) attempts per patient. Those
with a history of suicide attempts were found to have had more impulsive
actions than patients who had never attempted suicide.
Many individuals with borderline personality disorder and
other cluster B personality disorders have a history of suicide
attempts, but they may also have a history of self-mutilatory behaviors.
However, it is important to recognize that these three characteristics
define overlapping but not identical groups of individuals. Stanley
et al. (251) compared 30 suicide attempters with a cluster B personality disorder
and a history of self-mutilation to a matched group of 23 suicide
attempters with a cluster B personality disorder but no history
of self-mutilation. Individuals with a history of self-mutilation
had higher levels of impulsivity and aggression than those without
such a history. Herpertz et al. (253) examined characteristics of
self-mutilatory behaviors and found that an ongoing tendency for
behavioral dyscontrol was present only in patients exhibiting impulsive
self-mutilatory behaviors and not in those with premeditated self-mutilatory
behaviors. Thus, although self-mutilatory behaviors and impulsivity
share many associated features and antecedents and are
common among individuals with borderline personality disorder or
histories of physical or sexual abuse, self-mutilatory behavior
cannot be regarded as synonymous with impulsivity. In a similar
fashion, the presence of other risk-taking behaviors such as reckless
driving or unsafe sexual practices is not necessarily a reflection
of increased impulsivity per se. Nonetheless, the presence of impulsivity,
violence, risk-taking, or self-mutilatory behaviors requires a careful
assessment and plan of treatment to address these clinical characteristics and
minimize their effect on the risk of suicide and suicide attempts.
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4. Other aspects of psychiatric history
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a) Alcohol intoxication
Intoxication with alcohol and/or with other substances
is often found in individuals who have died by suicide, independent
of whether they meet the diagnostic criteria for a substance use
disorder. Hayward et al. (255) reviewed coroners' records
for 515 consecutive suicides in Western Australia and
found that 35.8% of the persons who died by suicide had
a nonzero blood alcohol level, with 24.5% being moderately
to significantly impaired by alcohol at the time of death. Alcohol
consumption before suicide was more prevalent in younger individuals,
with 44.8% of teenagers and 35.1% of those age
20–24 years having used alcohol, in contrast to 25.9% of
individuals over age 45 years. In addition, those with nonzero blood
alcohol levels were more likely to have experienced a breakup in
a relationship but less likely to have a history of psychiatric
illness or treatment.
As part of the National Suicide Prevention Project in Finland
(1987–1988), Ohberg et al. (121) conducted toxicological
screening in 1,348 consecutive suicides in a 1-year period and found
alcohol use before suicide in 35.9% of the sample. Alcohol
was present in men twice as often as in women, whereas prescribed
medications, which were found on toxicological screening in 41.6% of
suicides overall, were more commonly noted in women.
Brent et al. (151), in a study of suicides in 10- to 19-year-old
residents of Allegheny County, Pennsylvania, from 1960 to 1983,
found that the proportion of persons who died by suicide with detectable
blood alcohol levels rose from 12.9% in 1968–1972
to 46.0% in 1978–1983. In addition, individuals
who used a firearm for suicide were 4.9 times more likely to have
been drinking than individuals who used other suicide methods.
That intoxication increases the likelihood of suicide is also
suggested by the role of employment in modulating suicide risk among
alcohol users. Specifically, Pirkola et al. (260) found that alcohol misusers
who were employed were more likely to have died by suicide on a
weekend than those who were unemployed, suggesting that alcohol
use per se contributes to risk, perhaps by increasing impulsivity.
Alcohol intoxication is also a common concomitant of suicide
attempts. Borges et al. (715) assessed measures of alcohol intoxication
in 40 emergency department patients who had attempted suicide and
compared them to 372 patients who presented to the emergency department
because of animal bites or workplace or recreational accidents.
Patients with suicide attempts were significantly more likely to
be under the influence of alcohol, as measured by breath alcohol
testing or by self-report of alcohol consumption in the preceding
6 hours. In a study of 325 individuals with deliberate self-poisoning
who presented to a Brisbane hospital over a 12-month period, McGrath
(453) found that almost one-third had consumed alcohol before their
suicide attempt. Varadaraj and Mendonca (454) found similar rates
of intoxication in a study of 158 emergency department patients
who had attempted suicide by overdose, with 41% consuming
alcohol prior to the attempt and 29% having serum alcohol
levels above 80 mg/dl.
Individuals who have made a suicide attempt while intoxicated
are also at increased risk of later suicide. A study by Suokas and
Lonnqvist (258) included data for 1,018 individuals who made a total of
1,207 suicide attempts and were evaluated in the emergency department
of a Helsinki, Finland, hospital in a single year. Of these patients,
62% had recently consumed alcohol. Suicide attempts that
occurred while intoxicated were more likely to be impulsive. After
5.5 years of follow-up, suicide had occurred in 3.3% of
those who had used alcohol with their index suicide attempt. The
majority of deaths occurred within the initial year of follow-up,
yielding a 51-fold increase in risk of suicide, compared to the
general population in the initial year, and a 17-fold increase in
risk for the follow-up period as a whole. These findings suggest
a need for careful follow-up of intoxicated individuals who present
with a suicide attempt. In addition, they suggest a need to determine
whether prior suicide attempts occurred in the context of intoxication.
+
b) Past suicide attempts
A substantial percentage of individuals will die on their
initial attempt at suicide. For example, Isometsa and Lonnqvist
(266) found that 56% of the 1,397 individuals in the Finnish
psychological autopsy study had died with their first suicide attempt
and that this pattern was particularly evident in males (62%,
compared with 38% of females). In addition, however, individuals
with nonfatal suicide attempts have an increased likelihood of later
suicide. From a public health standpoint, this finding is particularly
important, given the high occurrence of attempted suicide, which
in recent decades has had annual rates ranging from 2.6 to 1,100
per 100,000, with lifetime prevalence rates ranging from 720 to
5,930 per 100,000 (2, 518).
Multiple studies have indicated that suicide attempts increase
the risk of subsequent suicide. In fact, depending on the length
of the follow-up period, from 6% to 10% of those
who attempt suicide will ultimately die by suicide. For example,
in follow-up studies of patients seen in psychiatric emergency settings
after a suicide attempt, 4%–12% die by
suicide within 5 years (268, 269, 275). In a 14-year follow-up of
1,018 deliberate self-poisoning patients, Suokas et al. (271) found
a 6.7% rate of suicide overall, with the rate in men approximately
twice that in women. Among 1,573 individuals who had been hospitalized
after attempted suicide and followed up 4–11 years later, Nordstrom
et al. (275) found an overall mortality of 11%, with a
suicide risk of 6%. Tejedor et al. (272), in a 10-year
follow-up of 150 patients admitted to a psychiatric department after
a suicide attempt, found an even higher mortality rate from suicide
(12%) as well as from natural causes (10%). Furthermore,
in a meta-analysis of literature on psychiatric disorders and suicide,
Harris and Barraclough (64) found that attempted suicide had a relative
risk of later suicide that was greater than that of any psychiatric
disorder. Compared to the general population, patients who attempted
suicide were at 38 times greater risk of suicide, with the majority
of evidence suggesting that this increase in suicide risk is related
to the recency of the suicide attempt. This effect has also been
noted by Nordstrom et al. (275), who found the greatest risk for
suicide during the first year after an attempt. In addition, among
the 1,397 individuals in the Finnish psychological autopsy
study, Isometsa et al. (266) found that a nonfatal suicide attempt
had occurred in 19% of the males and 39% of the
females in the year preceding their suicide. In contrast, Fawcett
et al. (79) found that among patients with a major affective disorder,
a history of previous suicide attempts was associated with suicide
that occurred more than 1 year after index hospital admission.
Other factors may also modulate suicide risk following a suicide
attempt. Harris and Barraclough (64) found that risk for suicide
after an attempt varied with measures of social cohesion and was increased
by the presence of long-standing physical illness or a history of
multiple previous attempts or prior psychiatric treatment. Risk
of suicide following a suicide attempt may also vary with gender, since
Nordstrom et al. (275) found a twofold increase in suicide risk
in males, compared with females, with the risk for younger male
attempters being four times that for younger females.
Other investigators have examined factors associated with
subsequent suicide attempts following an index suicide attempt.
Hjelmeland (164), for example, studied 1,220 patients who had attempted suicide
and compared those who had a repeated attempt within 12 months to
those who did not. Although there were no gender differences between
repeaters and nonrepeaters, repeaters were more likely to be unmarried,
to be unemployed, to abuse alcohol, and to report their own psychiatric problems
as their main concern. Repeaters were also more likely to have had
a history of sexual abuse, a criminal record, a recent address change,
or a relative or friend who had attempted suicide. Others have confirmed
an increased risk of repeated suicide attempts in individuals with
multiple prior attempts (272, 278). Aborted suicide attempts are
also common among those who attempt suicide (276).
Given this increased likelihood of suicide or additional suicide
attempts, particularly in the first few years after a suicide attempt,
assessment and treatment of suicide attempters should be an integral part
of risk reduction. All too often, however, suicide attempters do
not receive a psychiatric assessment or follow-up care (2, 279, 280). Thus, in addition to a thorough psychiatric assessment, determining
a patient's history of suicide attempts (including aborted
suicide attempts) yields information that is important in estimating
the level of suicide risk of an individual patient. Additional factors
such as psychiatric diagnosis, comorbid alcohol abuse, physical
illness, or psychosocial stressors may augment risk following a
suicide attempt. Furthermore, the significant mortality observed
in suicide attempters underscores the need for careful aftercare
planning for suicide attempters.
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c) History of childhood physical and/or
sexual abuse
Multiple studies have examined the association between childhood
abuse and suicidal behaviors, although few have examined the effect
of childhood abuse on risk for suicide per se. Plunkett et al. (36),
however, assessed 183 young people who had experienced childhood
sexual abuse and individuals from a nonabused comparison group 9
years after study intake. Those who had experienced childhood sexual
abuse had a suicide rate that was 10.7–13.0 times the national
rate, whereas no suicides occurred in the control group.
The bulk of studies have assessed the effects of childhood
abuse on suicidal ideation and suicide attempts, both of which are
common among individuals reporting childhood abuse. For example,
in the study by Plunkett et al. (36), 43% of the 183 young
people who had experienced childhood sexual abuse had thought of
suicide, whereas 32% had made a suicide attempt.
Other studies have examined the effect of childhood abuse
on the risk of suicidal ideation and suicide attempts. Fergusson
et al. (286), in an 18-year longitudinal study of a birth cohort
of 1,265 New Zealand children, found that those reporting childhood
sexual abuse had higher rates of suicidal behaviors than those not
reporting such abuse. In addition, the extent of childhood sexual
abuse was consistently correlated with risk, with the highest risk
of suicidal behaviors in those whose childhood sexual abuse involved
intercourse. Even after controlling for the effects of confounding
variables, the investigators found that those who reported harsh
or abusive childhood experiences were also at increased risk for
suicide attempts (282).
Brown et al. (294) followed a cohort of 776 randomly selected
children over a 17-year period to adulthood and found that adolescents
and young adults with a history of childhood maltreatment were three
times more likely to become suicidal than individuals without such
a history. Again, the effects of childhood sexual abuse on suicidal
behavior were greater than the effects of other forms of abuse, with
the risk of repeated suicide attempts being eight times greater
for youths with a history of sexual abuse.
Several Australian investigators have used data from twin
pairs to assess the effect of childhood abuse on the risk of suicidal
ideation or suicide attempts. In structured telephone interviews
with 5,995 Australian twins, Dinwiddie et al. (292) found that the
5.9% of women and 2.5% of men who reported a history
of childhood sexual abuse were more likely to report suicidal ideation
or prior suicide attempts. Nelson et al. (35), using data from 1,991
Australian twin pairs, found even greater rates of childhood sexual
abuse (16.7% of women and 5.4% of men) but confirmed
that a history of childhood sexual abuse significantly increased
risk for suicide attempts, with the greatest risk associated with
sexual abuse that involved intercourse. Even in twin pairs who were
discordant for childhood sexual abuse, both twins had increased
rates for many adverse outcomes, probably as a result of shared
family background risk factors. Nonetheless, the twin who reported
experiencing childhood sexual abuse had an even greater risk of
a subsequent suicide attempt than the co-twin, which suggests an
independent contribution of childhood sexual abuse to the risk for
suicidal behaviors.
In contrast to the authors of the longitudinal studies described
earlier, Romans et al. (291) selected a random community sample
of New Zealand women and compared those who reported having been sexually
abused as children to those who did not report such abuse. The presence
of self-harming behaviors was associated with sexual abuse in childhood
and was most marked in individuals who were subjected to more intrusive
and frequent abuse.
Cross-sectional assessments of nonpsychiatric populations
in the United States have also found associations between suicide
attempts and childhood abuse, particularly childhood sexual abuse. Among
the 2,918 respondents in the Duke University ECA study, Davidson
et al. (293) found that subjects reporting a history of sexual assault
also reported higher lifetime rates of suicide attempts than individuals
without such a history. In women, a history of sexual trauma before
age 16 was a particularly strong correlate of suicide
attempts. Among U.S. women physicians (N=4,501), data from
a nationally distributed questionnaire showed that the 4.7% of
respondents with a history of childhood sexual abuse were more likely
to report a history of suicide attempts (287). Kaslow et al. (230)
compared 148 low-income African American women who presented to
the hospital following a suicide attempt to a similar group of 137
women who presented for general medical care and found a threefold
greater risk of childhood maltreatment among suicide attempters.
Molnar et al. (33) analyzed data for 5,877 individuals from the
National Comorbidity Survey and found that individuals with a history
of sexual abuse were more likely to attempt suicide than those without
such a history. This risk differed by sex, with a two- to fourfold
increase in risk among women and a four- to 11-fold increase in
risk among men. Dube et al. (281), in a sample of 17,337 adults
(mean age=56 years), also found that the risk of suicide
attempts was increased in those who had experienced childhood abuse.
They observed this risk to be augmented by multiple other factors,
including parental separation or divorce, witnessing of domestic
violence, and living with substance abusing, mentally ill, or criminal
household members.
In addition to the augmentation of suicide risk associated
with sexual abuse, risk appears to be further increased among individuals
who have experienced multiple forms of abuse. Anderson et al. (289)
examined the association between childhood abuse and adult suicidal
behavior in a sample of low-income African American women. Compared
to the women who did not report experiencing any emotional, physical,
or sexual childhood abuse, those who experienced one, two, or three
forms of abuse were, respectively, 1.83, 2.29, or 7.75 times more
likely to attempt suicide. In addition, women who reported all three
types of abuse were more likely to attempt suicide than women who reported
one or two types of abuse.
Childhood abuse is particularly frequent among individuals
with psychiatric diagnoses and appears to increase the likelihood
of suicide attempts even after the effects of psychiatric comorbidity are
controlled. For example, in a study of 251 psychiatric outpatients
(68 men and 183 women), Kaplan et al. (284) found that 51% of
the subjects had reported experiencing childhood abuse, with 15% reporting
sexual abuse alone, 17% reporting physical abuse alone,
and 18% reporting a combination of physical and sexual
abuse during childhood. Abusive experiences in adulthood were reported
by 38% of the subjects, with physical abuse alone in 21%,
sexual abuse alone in 8%, and both physical and sexual
abuse in 9%. Compared to control subjects without a history
of abuse, subjects with a history of abuse were more likely to have
been suicidal at a younger age and to have made multiple suicide
attempts. Among patients with a history of abuse, suicide attempters
could be distinguished from nonattempters on the basis of higher
levels of dissociation, depression, and somatization. In analyzing data
from the National Comorbidity Survey, Molnar et al. (33) also found
that those with a comorbid psychiatric disorder were younger at
the time of their first suicide attempt than those without concomitant
psychiatric illness. In addition, a history of childhood sexual
abuse remained a risk factor for attempting suicide even after adjustment
for the effect of a lifetime psychiatric diagnosis.
The presence of childhood physical and/or sexual
abuse has also been associated with an increased likelihood of suicidality
in studies of patients with specific psychiatric diagnoses. For
example, Brodsky et al. (196), in a study of 214 inpatients with
a diagnosis of borderline personality disorder, found that the number
of lifetime suicide attempts was correlated with a history of childhood
abuse. Van der Kolk et al. (285) assessed 74 individuals with personality
disorders or bipolar II disorder and found that histories of childhood
sexual and physical abuse were highly significant predictors of
self-cutting and suicide attempts. During a follow-up period that
averaged 4 years, the patients who continued being self-destructive
were those with the most severe histories of separation and neglect and
those with past sexual abuse.
For individuals with major depressive disorder, evidence in
the literature is more complex. Brodsky et al. (250) found that
adults with major depressive disorder who had a history of childhood physical
or sexual abuse were more likely to have made a suicide attempt
than those who did not report an abuse history, even after adjustment
for the effects of impulsivity, aggression history, and presence
of borderline personality disorder. Zlotnick et al. (716), in a
study of 235 outpatients with major depression, found substantial
rates of diagnostic comorbidity, primarily with borderline personality
disorder and PTSD. After controlling for the effects of the presence
of these diagnoses, however, they did not find an independent contribution
of childhood sexual abuse to the likelihood of suicide attempts.
Childhood abuse is also prevalent among individuals with substance
use disorders and, again, is associated with increased rates of
suicide attempts. In a group of 481 male and 321 female alcoholic inpatients
(age 19–57 years), Windle et al. (288) found a high prevalence
of reported childhood abuse. For women, the rates of physical abuse
only, sexual abuse only, and dual abuse were 10%, 26%,
and 23%, respectively, whereas for men the corresponding
rates were 19%, 7%, and 5%, respectively. For
both sexes, a reported history of childhood abuse was associated
with a higher rate of suicide attempts, with an even larger effect
associated with a history of both physical and sexual abuse. Roy (290)
examined abuse histories in a consecutive series of 100 male cocaine-dependent
patients and found that the 34 patients who had attempted suicide
reported significantly higher scores for childhood emotional abuse,
physical abuse, sexual abuse, and emotional and physical neglect
than the 66 patients who had never made a suicide attempt.
In addition to increasing risk for suicide attempts within
community samples and across subgroups of psychiatric patients,
the presence of a childhood abuse history in individuals who have
made a suicide attempt should alert the psychiatrist to a further
increase in the risk of repeated attempts (284). Elliott et al.
(717) compared 65 patients hospitalized for a medically serious
suicide attempt to 32 patients seen in the emergency room for a
suicide attempt but who were not medically hospitalized. Those with
attempts that were not medically serious had higher rates of previous
sexual and physical abuse as well as higher rates of traumatic life
events and borderline personality disorder. Hjelmeland (164) also
found that patients in a Norwegian county who required medical treatment
after an initial suicide attempt were more likely to have a repeated
suicide attempt during 6 years of follow-up if they had a history
of being sexually abused.
In summary, there is consistent evidence, in multiple samples
studied with multiple study designs, that a history of abuse augments
the risk for later suicidal ideation and suicide attempts. The effect of
abuse on suicide per se has been less well studied, but the few
findings that are available suggest that abuse increases suicide
risk. Childhood abuse and particularly childhood sexual abuse appear
to be associated with greater increases in risk than childhood physical
abuse or abuse during adulthood. Individuals who have experienced
multiple forms of abuse are at particularly increased risk of suicidal ideation
and behaviors. Although a history of abuse is common in individuals
with suicide attempts and in individuals with a psychiatric diagnosis,
the contribution of childhood abuse to the risk of suicidal behaviors
seems to be independent of the effects of psychiatric diagnoses.
Consequently, in patients who have attempted suicide as well as
in those presenting for any type of psychiatric treatment, it is
important to inquire about childhood and adult experiences of physical,
sexual, or emotional abuse and to incorporate this information into
the risk assessment and treatment planning process.
+
d) History of domestic partner violence
Although studies have not directly assessed the effects of
domestic partner violence on risk for suicide, domestic partner
violence has been associated with increased rates of suicide attempts
and suicidal ideation. For example, after adjustment for the effects
of sociodemographic characteristics and alcohol use in a nationally
representative sample of 5,238 U.S. adults, Simon et al. (298) found
that being physically assaulted was associated with suicidal ideation
or behavior (odds ratio=2.7) and that this pattern was
particularly true for individuals who sustained injury (odds ratio=3.4)
or were assaulted by a relative or intimate partner (odds ratio=7.7).
McCauley et al. (300) surveyed 1,952 respondents in a primary medical
care practice and found that 5.5% had experienced domestic
violence in the year before presentation. Compared with women who
had not recently experienced domestic violence, those with recent
experiences of such violence were four times more likely to have
attempted suicide. Among women physicians (N=4,501 respondents)
who responded to the Women Physicians' Health Study questionnaire,
suicide attempts were significantly more prevalent among the 3.7% of respondents
with a history of domestic partner violence (34).
Domestic partner violence is particularly a risk factor for
suicide attempts among women in low-income urban environments. In
a group of 648 women, most of whom were young and unemployed and
had an annual household income of less than $10,000, Abbott
et al. (299) found that among the 418 women with a current male
partner, 11.7% reported being recently assaulted, threatened,
or intimidated by their partner. For the entire sample, the cumulative
lifetime prevalence of exposure to domestic violence was 54.2%.
Women with any exposure to domestic partner violence had an increased
rate of suicide attempts, compared to women without such exposure
(26% and 8%, respectively). Kaslow et al. (230)
compared 148 low-income African American women who presented to
the hospital after a suicide attempt to a similar group of 137 women
who presented for general medical care. Women who presented with
a suicide attempt had a greater likelihood of having experienced
either physical or nonphysical partner abuse (odds ratios=2.5
and 2.8, respectively). Thompson et al. (301), in a sample of low-income,
inner-city women, found that suicide attempters (N=119)
were approximately three times more likely to experience significant
physical partner abuse, nonphysical abuse, and PTSD than nonattempters
(N=85). In addition, increased suicidality in individuals
who were experiencing physical partner abuse appeared to depend
on the presence of PTSD rather than the independent contribution
to risk of the abuse.
Increased risk for suicide attempts is also seen in battered
women presenting to emergency department settings or to women's
shelters. Muelleman et al. (296) surveyed 4,501 women between age
19 and 65 years who presented to 10 hospital-based emergency departments
in two cities serving inner city, urban, and suburban populations.
Of these, 266 (5.9%) had definite or probable battering
injuries and an additional 266 (5.9%) were currently
in a physically abusive relationship but did not present with evidence
of a battering injury. Compared to the 3,969 women (88.2%)
who were not currently in a physically abusive relationship, women
in physically abusive relationships were more likely to present
to the emergency department after an attempted suicide. In a cross-sectional
study of 203 women seeking refuge in battered women's shelters,
Wingood et al. (297) found, after controlling for the effects of
sociodemographic characteristics, that women experiencing both sexual
and physical abuse were more likely to have attempted suicide than
women experiencing physical abuse alone.
Although much more commonly experienced by women, domestic
partner violence also affects men. Ernst et al. (302) surveyed 233
men and 283 women who presented to an inner-city emergency department
for past and current histories of domestic partner violence and
found that such experiences were associated with increased rates
of suicidal ideation in both sexes. It is important to note that men
with a history of domestic violence toward their partners may also
be at increased risk for suicide. Conner et al. (303), for example,
noted that one-half of the 42 male alcoholics who died by suicide and
were originally described by Murphy et al. (149) had a history of
domestic violence.
Domestic violence in the home may also affect the risk for
suicide attempts among those who witness that violence. Dube et
al. (281) examined the relationship to suicide attempts of eight
adverse childhood experiences, including witnessing domestic violence,
in 17,337 adults (mean age=56 years) and found that childhood
exposure to parental domestic violence increased the risk of later suicide
attempts.
Thus, although data on suicide risk per se are not available,
there is clear evidence that domestic partner violence is associated
with an increased risk of suicide attempts. In addition, although evidence
is more limited, individuals who become violent with their partners
or who observe domestic partner violence may also be at increased
risk for suicidal behaviors. Since a past or current history of
domestic partner violence is often overlooked, even in settings
such as emergency departments where it is quite prevalent, it is
important to specifically ask about domestic partner violence as
a part of the suicide assessment.
A past history of treatment of mental illness, including a
past history of hospitalization, should be viewed as a marker that
alerts the clinician to an increase in suicide risk (64, 198). Furthermore, greater
treatment intensity is associated with a higher rate of eventual
suicide. For example, Bostwick and Pankratz (77) used meta-analytic
techniques to calculate suicide risks for outpatients, inpatients, or
suicidal inpatients and found a hierarchy in suicide risk among
patients with affective disorders. The estimated lifetime prevalence
of suicide in those ever hospitalized for suicidality was 8.6%, compared
to a lifetime suicide rate of 4.0% for all hospitalized
patients. For mixed inpatient/outpatient populations, the
lifetime suicide prevalence was even lower, at 2.2%, whereas
for the population without affective illness, it was less than 0.5%.
A similar phenomenon was noted by Simon and VonKorff (718) among
patients treated for depression in a large health plan in western Washington
State. Computerized discharge diagnoses, outpatient visit diagnoses,
and outpatient prescription records were used to identify all enrollees
who received treatment for depression during a 3-year period. During
the study period, 35,546 individuals received some treatment for
depression and accounted for 62,159 person-years of follow-up. Thirty-six
individuals (4.2% of all deaths) were classified as having
definitely or possibly died by suicide, yielding an overall suicide
mortality rate of 59 per 100,000 person-years, with the rate for
men more than threefold higher than the rate for women. Patients
who received any inpatient psychiatric treatment had a risk for
suicide of 224 per 100,000 person-years, with suicide rates among
those who received outpatient specialty mental health treatment
and those treated with antidepressant medications in primary care
of 64 and 43 per 100,000 person-years, respectively. No patient
with a diagnosis of depression who was treated only in primary care
and who did not receive antidepressant medication died by suicide.
In terms of suicide attempts, Pirkis et al. (198) analyzed
data for 12,229 patients in 13,632 episodes of care and found that
the risk of suicide attempts was 10-fold higher in acute inpatient
settings, compared with longer-stay inpatient or community-based
settings (5.4 attempts per 1,000 episode-days, compared with 0.6
and 0.5 attempts per 1,000 episode-days, respectively). Thus, the
rate of suicidality is increased in individuals with prior inpatient
treatment, although it is not clear whether the rate is higher because
the patients have more severe illnesses (and are deemed to be at
increased risk for suicide) or because hospitalization increases
suicide risk by increasing emotional or psychosocial distress.
Temporally, the risk for suicide appears to be greatest after
changes in treatment setting or intensity (304). Recently admitted
and recently discharged inpatients show particularly increased risks
(64, 72), and this pattern is seen across diagnostic categories
(91, 95, 305–308). Rates decline with time since discharge
but may remain high for as long as several years (91, 306, 309).
For example, Pirkis and Burgess (309) systematically reviewed the
literature on suicide and health care contacts and found that up
to 41% of those in the general population who die by suicide
may have had psychiatric inpatient care in the year before death,
with up to 9% dying by suicide within 1 day of discharge. Appleby
et al. (304) compared individuals who died by suicide within 5 years
of discharge from psychiatric inpatient care to surviving demographically
matched patients and found that those who died by suicide were more
likely to have had their care reduced at the final appointment in
the community before death (odds ratio=3.7).
Black et al. (91) assessed 5,412 patients admitted to the
University of Iowa Psychiatric Hospital and found that 331 died
over a 9-year follow-up period. Ninety-nine percent of all premature
deaths occurred during the initial 2 years after discharge, with
the risk for premature death being greatest among women and the
young. Over the initial 2-year period, 29% of deaths were
by suicide and suicide occurred at a rate that was more than 50
times the expected rate for the group as a whole.
Roy (96) compared 90 psychiatric patients who had attempted
suicide (53 male patients and 37 female patients) to a group of
90 matched control subjects who had not attempted suicide. Of the
75 patients who had died by suicide as outpatients, 58% had
seen a psychiatrist within the previous week, 81% had been
admitted in their last episode of contact, and 44% of those
who had been inpatients attempted suicide within 1 month of discharge.
Goldacre et al. (307) determined the risk of suicide within
a year of psychiatric discharge in a population-based study in Oxford,
U.K., and found that SMRs for suicide in the first 28 days after discharge
from inpatient care were 213 and 134 for male and female patients,
respectively. The rate of suicide in the first 28 days after discharge
was 7.1 times higher for male patients and 3.0 times higher for
female patients than the rate during the remaining 48 weeks of the
first year after discharge.
More recently, Appleby et al. (306) analyzed data for 10,040
individuals in the United Kingdom who died by suicide over a 2-year
period and found that 2,370 (24%) had been in contact with
mental health services in the 12 months before death. Of these,
358 (16%) were psychiatric inpatients at the time of death,
and one-fifth of those patients were being monitored with special
observation procedures. An additional 519 suicides (24%)
occurred within 3 months of hospital discharge, with the highest
number occurring in the first week. Rossau and Mortensen (95) found
that 508 suicides occurred among 9,156 patients who were admitted
to psychiatric hospitals in Denmark between 1970 and 1987 and who
received a diagnosis of schizophrenia for the first time. Suicide
risk was particularly high during the first 5 days after discharge,
and risk was also increased in individuals with multiple admissions during
the prior year.
Similar findings have been reported for suicide attempts,
which are also more frequent in the period following hospitalization.
Oquendo et al. (267) followed 136 patients after hospitalization
for major depressive disorder and found that 15% of the
subjects made a suicide attempt within 2 years, with more than 50% of
attempts occurring within the first 5 months of follow-up.
Given that the intensity of past treatment is associated with
risk for suicide and suicide attempts, the treatment history is
an important part of the assessment process. In addition, these
observations suggest specific points in the course of treatment
(e.g., hospital discharge or other changes in treatment setting) at
which risk of suicidal behaviors may be particularly increased.
Awareness of these factors will allow the psychiatrist to take them
into consideration in developing a plan of treatment with the patient.
+
f) Illness course and severity
In some psychiatric disorders, suicide risk is greater at
certain points in the illness or episode course. Multiple studies
have shown that suicidality tends to occur early in the course of
affective disorder, often before diagnosis or before treatment
has begun (310, 719). These observations emphasize the importance
of early identification of these disorders and early implementation
of effective interventions.
Appleby et al. (304) compared individuals who died by suicide
within 5 years of discharge from psychiatric inpatient care to surviving
demographically matched patients and found that suicide was more
likely in those whose index hospitalization was at the beginning
of their illness (odds ratio=2.0). Bradvik and Berglund
(317) followed 1,206 inpatients who had received a discharge diagnosis of
severe depression/melancholia between 1956 and 1969. At
the time of the initial follow-up in 1984, 22% had died
by suicide, whereas by the second follow-up in 1998, an additional
4% had died by suicide. Although mortality due to suicide
declined with time, the standardized mortality was still increased
late in the course of depressive illness (SMR=1.3). Osby
et al. (73) identified all patients in Sweden with a hospital diagnosis
of bipolar disorder (N=15,386) or unipolar depressive disorder (N=39,182)
between 1973 and 1995 and determined the date and cause of death
using national registries. They found that the SMR for suicide was
especially high for younger patients during the first years after
initial diagnosis, although an increasing SMR was found for female
patients with major depressive disorder over the course of the study.
Fawcett et al. (313) found that for the 954 patients with major
affective disorder in the NIMH Collaborative Program on the Psychobiology
of Depression, 32% of the 25 suicides occurred within 6
months and 52% occurred within 1 year of entry into the
study.
Suicide has been noted to be more likely early in the illness
course in individuals with schizophrenia. Westermeyer
et al. (83), for example, compared 36 patients with schizophrenia
who died by suicide to a similar group of patients who did not die
by suicide and found that individuals with schizophrenia and other
psychotic disorders were especially vulnerable to suicide within
the first 6 years of their initial hospitalization. Suicides were
present throughout the course of schizophrenia in the National Suicide
Prevention Project in Finland (100).
Although patients' risks for suicide and suicide
attempts later in the illness course are less than those earlier
on, their risks remain greater than those in the general population
(74, 100, 316, 317). Angst et al. (74) followed 406 hospitalized
patients with affective disorder for 22 years or more and found
that the suicide rate was most elevated at the age of onset but
that, from age 30 to 70 years, the suicide rate was remarkably constant
despite the different courses of illness. Ahrens et al. (316) examined
the illness course of 310 patients with mood disorder, 98 of whom
had made a suicide attempt, and found no significant correlation
between age and suicide attempts, suggesting that the rate of suicide
attempts was not declining as the patient aged and the illness progressed.
Malone et al. (312) analyzed data for 100 inpatients during a major
depressive episode and noted that the first 3 months after the onset
of a major depressive episode and the first 5 years after the lifetime
onset of major depressive disorder represented the highest-risk
period for attempted suicide, independent of the severity or duration
of depression.
Risk for suicide may also vary with the severity of symptoms.
For example, Brown et al. (78) prospectively followed 6,891 psychiatric
outpatients and found that in the 49 (1%) who died by suicide the
severity of depression, hopelessness, and suicide ideation were
significant risk factors. In contrast, in individuals with schizophrenia,
low levels of negative symptoms have been associated with increased
suicide risk (93).
It is also important to recognize that other factors such
as age modulate the effects of symptom severity on risk. With older
adults, for example, milder symptoms may be associated with greater risk
than moderate symptoms in younger adults (66). Waern et al. (207)
analyzed data for 85 individuals over 65 years of age who had died
by suicide and 153 randomly selected living comparison subjects
and found that elevated suicide risk was associated with minor as
well as major depressive disorder.
In terms of attempted suicide, Mann et al. (31) followed 347
consecutive patients after admission to a university hospital and
found that the objective severity of current depression or psychosis
did not distinguish the 184 patients who had attempted suicide from
those who had never attempted suicide. However, those who had attempted
suicide reported higher levels of subjective depression and suicidal
ideation and fewer reasons for living. Corbitt et al. (195), using
data from structured interviews of 102 psychiatric inpatients, found
that past suicidal behavior was better predicted by the number of
criteria for borderline personality disorder and other cluster B
personality disorders that were met than by depressive symptoms.
That the risk for suicidality may be associated with symptom
or illness severity suggests that it is important to determine the
magnitude and not simply the presence of risk factors as part of
the assessment process. In addition, when estimating risk and implementing
a plan of treatment to address risk, variations in risk with illness
course may need to be considered in the context of other patient-specific
factors.
Considerable evidence derived from a variety of sources supports
a link between physical illness and suicide (Table 7). Methods used
to establish this relationship have included record linkage and prospective
cohort studies of clinical samples with specific physical illnesses,
as well as retrospective examinations of the prevalence of specific
physical illnesses in samples of individuals who took their own
lives.
Harris and Barraclough (25) conducted a comprehensive, systematic
literature review and meta-analysis to determine the suicide risk
associated with 63 specific physical disorders that had been posited
to influence this risk. They did not include reports of epilepsy,
conceding that the evidence base was already strong for its association
with suicide. Their review yielded 235 reports that met the specific
criteria for consideration, from which data were abstracted to enable
calculation of pooled SMRs for each condition. The authors concluded
that the disorders demonstrating significantly increased risk for
suicide included HIV/AIDS, Huntington's disease,
malignant neoplasm, multiple sclerosis, peptic ulcer disease, chronic
hemodialysis-treated renal failure, spinal cord injury, and systemic
lupus erythematosus. The data were insufficient to conclude whether
amputation, valve replacement, intestinal diseases, cirrhosis, Parkinson's
disease, or systemic sclerosis conferred an increased risk for suicide.
Surprising findings included the association of amyotrophic lateral sclerosis,
blindness, stroke, diabetes mellitus, rheumatoid arthritis, and
hypertension with only average risk that was no greater than that
in the general population. Pregnancy and the puerperium were associated
with a statistically reduced risk for suicide. Although the authors
were unable to examine the influence of mental disorders or other
mediating or moderating effects, many of the disorders associated
with increased risk are also associated with mental disorders (e.g.,
multiple sclerosis with depression and peptic ulcer disease with
alcohol abuse). Therefore, when the influence of comorbid psychiatric
illness is accounted for, the independent risk associated with physical
illness may be less.
Quan and colleagues (337) reported results of a record linkage
study conducted in Alberta, Canada, that was designed to establish
whether specific illnesses distinguish persons who died by suicide from
comparison subjects who died in accidents. In univariate statistical
analyses comparing 822 persons age 55 years and older who died by
suicide with 944 subjects of similar age who died in motor vehicle
accidents, those who died by suicide were more likely to have had
malignant neoplasm, arteriosclerotic heart disease, chronic obstructive
pulmonary disease, peptic ulcer disease, prostate disorders, depression,
and other psychiatric diagnoses. In multivariate analyses in which
the effects of demographic and health characteristics were controlled,
arteriosclerotic heart disease and peptic ulcer disease did not
differentiate the groups. Among the physical illnesses, only malignant
neoplasm and prostate disorders (excluding prostate cancer) remained
significant predictors, along with chronic obstructive pulmonary
disease in married (but not single) men.
Grabbe and colleagues (338) used data from the National Mortality
Followback Survey to identify health status variables related to
suicide in older persons, compared with natural deaths and deaths from
injury. In comparing suicides with injury deaths, they found that
malignant neoplasm, but not lung conditions, was associated with
increased risk. The presence of a stroke, paradoxically, appeared to
lower risk. The study reinforced the powerful influence of cancer.
Other studies have also specifically looked for associations
between suicide and central nervous system disorders that are known
to increase the rates of depressive syndromes. Stenager et al. (334), for
example, found that patients with a diagnosis of multiple sclerosis
after age 40 were at no greater risk for suicide than control subjects,
but that men and women who received this diagnosis before age 40
were at approximately three times and two times greater risk, respectively.
Stenager et al. (720) also cross-referenced data for all patients
discharged with a diagnosis of a cerebrovascular accident in selected
areas of Denmark between 1973 and 1990 with death records and found
140 suicides among almost 38,000 patients with a history of cerebrovascular
accident and increased suicide risks for both men and women with
this diagnosis in all age groups. In general, risk for suicide was
higher in women than in men and in age groups under age 60 years,
compared to older adults. The group at highest risk was women under
age 50 with a stroke, who had a risk for suicide almost 14 times
greater than that for women of similar age in the general population.
These data provide additional support for an association between
suicide and cerebrovascular disease, particularly among younger
and middle-aged stroke patients.
Evidence for increased suicide risk in people with epilepsy
is similarly strong. Stenager and Stenager (323) examined all published
reports concerning the link between suicide and neurologic disorders
in order to critically evaluate the strength of the evidence. They
identified a variety of common methodologic problems in this body
of research, including sources of bias in selection of cases, inadequate
definition of control samples, imprecise definitions of disease,
inadequate sample sizes, absent or imprecise definitions of suicidal
behavior, and inadequate follow-up intervals. Nonetheless, they
concluded that sufficiently rigorous studies of patients with multiple
sclerosis, patients with spinal cord injury, and selected groups
of patients with epilepsy did establish increased risk in these
conditions. The most rigorous studies examining risk associated
with epilepsy were conducted by White and colleagues in 1979 (324).
They followed 2,099 patients with epilepsy who had been committed for
institutional care and treatment and compared their risk for suicide
with that in an age- and sex-standardized control population. They
found that individuals with epilepsy were at 5.4 times higher risk
for suicide than the control subjects.
Rafnsson et al. (326) analyzed data for 224 individuals who
first received a diagnosis of unprovoked seizures in Iceland between
1960 and 1964 and who were followed for up to 25 years. Among men,
the relative risk of dying by suicide was almost six times the expected
risk in the general population, and the rates of death from accidents,
poisoning, and violence were about three times the expected rates.
Nilsson et al. (325) used data from the Swedish National Cause
of Death Register to determine causes of death among 6,880 patients
with a diagnosis of epilepsy registered in the Stockholm County In-Patient
Register. In a comparison of 26 individuals who died by suicide
and 23 individuals suspected of having died by suicide with 171
living control subjects, individuals with an onset of epilepsy before
age 18 had a higher risk for suicide than those with comorbid psychiatric
diagnoses or those treated with antipsychotics. However, unlike
other studies, this study did not find a specific association with
particular types of epilepsy, including temporal lobe seizures.
Suicide attempts also appear to be increased in frequency
among patients with epilepsy, compared to the general population.
Hawton et al. (330) analyzed data for patients admitted after deliberate self-poisoning
or self-injury over a 2-year period and found that the number of
patients with epilepsy was five times higher than general population
prevalence rates. Mendez et al. (329) compared 175 outpatients with
epilepsy to a group of 70 comparably disabled outpatients and found
that prior suicide attempts were reported by 30% of the
patients with epilepsy, compared to only 7% of the control
subjects. Rates of depression were similarly increased among the
patients with epilepsy (55%, compared with 30% of
the control subjects). In a subsequent study, Mendez et al. (331)
compared 62 patients with epilepsy to 62 patients with schizophrenia
and to 62 patients with both diagnoses and found that suicidal behaviors
were more common among individuals with epilepsy.
The association between terminal physical illnesses and suicide
is complex. Brown and colleagues (721) found that 34 of 44 terminally
ill patients receiving palliative care had never wished for an early death.
All of the 10 patients who had wished for an early death were found
to have clinical depressive illness, but only three reported suicidal ideation.
Chochinov and colleagues (342) interviewed 200 patients
who had terminal cancer to determine their psychiatric status and
whether they had thoughts of death. Almost 45% had wished
for an early death, but in only 8.5% were the thoughts
serious and persistent. Predictors of desire for death included
pain, a low level of family support, and clinically significant
depression. Diagnosable depressive illness was found in almost 60% of
those with a desire to die and in 8% of those without a
desire to die.
Other features of physical illness that may augment the likelihood
of suicidal ideation or suicide include functional impairments (338),
pain (340, 341), disfigurement, increased dependence on others,
and decreases in sight and hearing (321, 333). Waern et al. (333)
compared consecutive records of people who had died by suicide (46
men and 39 women) with those of living control participants selected
from the tax register (84 men and 69 women) in Gothenburg, Sweden.
In addition to neurological disorders and malignant disease, which
were associated with three- to fourfold increases in suicide risk,
visual impairment and serious physical illness of any type were
also associated with increased risk, with odds ratios of 7.0 and
6.4, respectively. Although the number of women in the sample was
small, the risk appeared to be greater among men, particularly in
those with a high burden of physical illness. Conwell et al. (321)
also found physical illness burden and functional limitations to
be more common among individuals seen in primary care settings who
die by suicide. They compared 196 patients age 60 years and older
from a group practice of general internal medicine (N=115)
or family medicine (N=81) to 42 individuals age 60 years
and older who had visited a primary care provider and who died by
suicide within 30 days of their visit. Those who died by suicide
were significantly more likely than control subjects to have had
a depressive illness, greater functional impairment, or a larger
burden of physical illness.
While several studies have shown that people with HIV and
AIDS are at high risk for suicide, the data on the extent of that
risk vary. In particular, suicide risk among people with HIV/AIDS
is likely to relate to other comorbid factors such as substance
abuse and other psychiatric diagnoses, stigma, social isolation,
and lack of support (722), as well as the direct effects of HIV
on the brain (335, 723). Even at the time of HIV serum antibody
testing, suicidal ideation is highly prevalent, being noted by about
30% of individuals and diminishing over time after notification
of test results (724). Nonetheless, elevations in the suicide rate
are present among persons with AIDS and range from seven to 36 times
the rates in comparable age- and sex-matched populations (335, 336, 725). For example, Marzuk et al. (335) studied suicide rates in
1985 in New York City and found a rate of 18.75 per 100,000 person-years
for men age 20–59 years without a known diagnosis of AIDS,
compared to 680.56 per 100,000 person-years for those with a known
diagnosis of AIDS, a 36-fold increase in relative risk. Cote et
al. (336) used public-access AIDS surveillance data and National
Center for Health Statistics multiple-cause mortality data for the
period from 1987 through 1989 to identify suicides among persons
with AIDS and found that all but one of the persons who died by
suicide were male. Compared to demographically similar men in the
general population, men with AIDS had a rate of suicide that was
7.4-fold higher, at 165 per 100,000 person-years of observation.
Cote et al. also noted that the suicide risk for persons with AIDS
decreased significantly from 1987 to 1989, suggesting that the rate of
suicide associated with AIDS may be decreasing.
In summary, physical illnesses are associated with increased
risk for suicide. The strength of the evidence for malignant neoplasms,
central nervous system disorders, peptic ulcer disease, and HIV/AIDS is
strong. Although the evidence is less compelling, indications are
that a range of other conditions may also be associated with suicide
and suicidal behaviors. It is probable that mood and substance use
disorders, either as precipitants or sequelae, account in part for
the increased SMRs for suicide ascribed to specific physical conditions
in the literature. However, further study is needed to determine
the role of social and psychological factors as mediators or moderators
of the relationship between physical illness and suicide. As a result,
in assessing suicide risk among individuals with physical illness,
consideration should be given to the presence of comorbid mood symptoms
as well as to the functional effects of the illness.
Findings from at least three types of studies suggests that
risk for suicide has a familial and probably genetic contribution.
These include: 1) strong and consistent findings that risk for suicidal behavior
is much higher among first-degree relatives of individuals with
suicide attempts or deaths than in the general population, 2) higher
concordance for suicidal behavior among identical versus fraternal
twins, and 3) greater risk of suicidal behavior among biological
versus adoptive relatives of persons adopted early in life who later
died by suicide (365–368). These familial associations appear
to be accounted for only partly by familial risks for major affective
illness or other clinical risk factors for suicide. Recent efforts
to specify molecular genetic markers that segregate or
associate with suicidal behavior, including those relating to the
serotonin (5-hydroxytryptamine [5-HT]) neurotransmission
system, have yielded inconsistent findings that are not easily interpreted
(17, 366, 368).
Evidence from family studies of suicide was recently summarized
by Turecki (368). In addition to studies showing increased rates
of suicidal behaviors among family members of suicidal individuals
(31, 82, 360–364), at least 20 reports of controlled comparisons
involving more than 11,000 subjects have been published (202, 214,
312, 344–359). The pooled overall relative risk of suicidal behavior
in first-degree relatives of suicidal probands compared to control
or population risks, weighted by the number of subjects in each
study, was 4.48 (95% CI=3.71–5.25), indicating
a nearly 4.5-fold excess of risk of suicidal behavior among relatives
of suicidal subjects, compared to nonsuicidal subjects (R. Baldessarini,
personal communication, 2002).
Across studies, reported estimates of relative risk for suicidal
behavior within families vary greatly, depending in part on the
types of behavior included (suicide, suicide attempts of varying lethality,
or both) and their defining criteria, the prevalence of psychiatric
risk factors for suicide among the control subjects, the closeness
of kinship (first-degree relatives, including parents and siblings,
with or without second-degree relatives), and differences in sample
size. Such studies, while demonstrating a powerful association,
do not prove genetic risk nor rule out shared environmental factors.
Moreover, it remains to be proved that the relationship for suicide
is separable from the well-known heritability of leading risk factors
for suicide, including major affective illness. Nevertheless, the
findings from pooled family studies strongly support the conclusion
that overall risk for suicidal behavior is at least four times greater
among close relatives of suicidal persons than among unrelated persons.
A powerful method of separating risks that result from shared
environments from risks that result from genetic factors is to compare
the rate of concordance (index condition appearing in both twins) for
a condition between identical, or monozygotic (single-egg), twins
and fraternal, or dizygotic (two-egg), twins. Risks for dizygotic
twins should be similar to those found among other first-degree family
members in family studies. Seven such twin studies pertaining to
suicide were identified in the research literature (365, 370–375)
and reviewed by Roy et al. (365, 369) and Turecki (368). None of
the studies involved samples of twins raised separately from early
life, and, thus, the confounding effects of shared environments
were possible. Moreover, the size and statistical power of these
studies varied markedly, from an analysis of a single monozygotic
twin-pair (373) to a study of an entire Australian national twin
registry involving more than 1,500 monozygotic and nearly
1,200 dizygotic twin-pairs (375). When the data from all seven twin
studies were pooled, the overall concordance rate for suicide or
suicide attempts, weighted for the numbers of subjects
involved, was 23.5% (401 of 1,704) for monozygotic
twin-pairs and 0.135% (two of 1,486) for dizygotic twin-pairs,
for a highly significant 175-fold increase in pooled relative risk
in the monozygotic twin-pairs (R. Baldessarini, personal
communication, 2002). Given the low frequency of suicidal behavior
found among fraternal co-twins, this relative risk is likely to
be a quantitatively unstable estimate. Nevertheless, its magnitude
strongly supports a genetic contribution to suicidal behavior. A
highly significant fourfold excess of risk in identical twins remained,
even after statistical corrections for depressive and other psychiatric
morbidity associated with suicide (375). Therefore, twin studies
add strong support for the heritability of suicide risk that is
separate from the heritability of risk factors such as mood disorders
but that is still likely to be influenced by environmental factors.
A less commonly employed technique to separate genetic from
shared environmental factors is to study outcomes for persons adopted
from their biological families very early in life. For the study of
suicide, this approach has been reported only three times, and each
study used the same Danish health and vital statistics registers
that included data for 5,483 adoptions in greater Copenhagen between
1924 and 1947 (376–378). When data for suicide were pooled
across all studies, to include affectively as well as psychotically
ill probands (376, 378), there was an approximately fivefold greater
risk among biological than among adoptive relatives (20 of 543 subjects [3.68%] versus
two of 263 subjects [0.76%]).
Later, the same American and Danish collaborators (378) compared
all adoptees identified as having an affective spectrum disorder
(N=71) with matched control adoptees without such disorders (N=71).
The index disorders included not only DSM-III major depression and
bipolar disorder but also milder "neurotic" depressions
and a condition ("affect reaction") marked by
affective instability that may resemble some forms of personality
disorder in current classifications. In relatives of affectively
ill adopted probands, there was a significant, approximately sevenfold
greater risk for suicide in biological relatives, compared with
adopted relatives (15 of 387 subjects [3.88%] versus one
of 180 subjects [0.56%]). Further analysis
of the suicide rate for biological relatives, compared with control
subjects, also yielded a highly significant 13.3-fold difference
(15 of 387 subjects [3.88%] versus one
of 344 subjects [0.29%]) (378). In striking
contrast, however, when suicide attempts were considered separately,
there was a 1.16-fold lower but nonsignificant risk in the biological
relatives, compared with the adoptive relatives, of affectively
ill adopted probands (13 of 387 subjects [3.36%] versus
seven of 180 subjects [3.89%]). A similar
comparison of the rate of suicide attempts in biological relatives
of adopted probands and in matched but not affectively ill control
subjects showed a modest 2.89-fold difference that failed to reach
significance (13 of 387 subjects [3.36%] versus
four of 344 subjects [1.16%]). Among
relatives of index adoptees with a diagnosis of schizophrenia, there
was a nonsignificant 2.67-fold greater risk for suicide
in biological relatives, compared with adoptive relatives (five
of 156 subjects [3.20%] versus one of
83 subjects [1.20%]) (376).
Matched comparison of 57 early-adopted individuals who died
by suicide with other adoptees lacking evidence of suicide or psychiatric
illnesses also showed a great excess risk of suicide in biological
over adoptive relatives (12 of 269 subjects [4.46%] versus
none of 148 subjects [0.00%]) (378).
Risk of suicide was approximately sixfold greater in relatives of
suicidal probands compared to relatives of matched, nonsuicidal
control subjects (12 of 269 subjects [4.46%] versus
two of 269 subjects [0.74%]). However,
this study did not consider the possible coincident heritability
of clinical risk factors for suicide, such as major affective illnesses
and substance use disorders.
Overall, these adoption studies indicate a greater risk of
suicide, but not of suicide attempts, among biological relatives
of suicidal probands, compared with adoptive relatives. They also
show greater risk among biological relatives of probands, compared
with control subjects, that is consistent with the hypothesis that
suicidality is heritable. Given the broader range of severity and
lethality of suicide attempts and the greater likelihood of environmentally
determined actions in many instances, the heritability of suicide
may well be much greater than that of suicide attempts.
+
7. Psychosocial factors
Unemployment has long been associated with increased rates
of suicide (379, 380, 726). Furthermore, the link between suicide
and unemployment has been confirmed by a recent study that used
U.S. National Longitudinal Mortality Study data to assess whether
unemployed individuals were at greater risk for suicide than employed
persons (24). At 2-year follow-up, unemployed men were two to three times
more likely to have died by suicide, compared with employed men.
Living alone, being divorced, and having lower socioeconomic status
increased the suicide risk. At or beyond 4 years of follow-up,
however, there was no statistical association between unemployment
and suicide for men. For women, the relationship between suicide
and unemployment was even stronger and longer-lasting. Unemployed
women had a much higher risk for suicide at each year of follow-up
than employed women. Unemployed women continued to show an elevated
risk at 9-year follow-up, by which time they were three times as
likely to die by suicide as employed women. As with men, younger
unemployed women were more at risk than women over age 45 years.
While the number of women who died by suicide was small, the results
remain significant and powerful. While in the past men were considered
most at risk for suicide after becoming unemployed, it is now known
that women are at an even greater risk and for a longer period of
time. The relationship between unemployment, suicide, and psychiatric
disorders remains unclear. Persons with psychiatric disorders may
be more likely to quit jobs or to be fired as well as more likely
to die by suicide (727).
Areas with socioeconomic deprivation also have larger numbers
of unemployed people, and these differences have been used to examine
effects of unemployment on rates of suicide and suicide attempts.
Hawton et al. (386), for example, analyzed data for different wards,
or communities, within Oxford, England, and found that wards with
the highest socioeconomic deprivation were associated with the highest
rates of suicide attempts. Individuals who attempted suicide, both
men and women, were more likely to be unemployed, living alone,
and having problems with housing. For men, but not for women, a
strong association was also found between the rate of suicide attempts
and socioeconomic deprivation. Men living in less deprived areas
who had financial problems were even more likely to attempt suicide,
suggesting that the dissonance between one's own financial
status and that of the neighborhood may affect risk. Unemployment
and financial problems can affect suicide in other ways as well.
Alcohol consumption and marital conflict, each of which increases
with financial difficulties or unemployment, may also contribute
to increased risk for suicidal behaviors.
Political context and large-scale economic changes can also
influence suicide and may provide clues about the effect of employment
status on suicide rates. During times of war, for example, suicide rates
decline (728), whereas increased suicide rates are found in political
systems associated with violence or social movements. Areas of the
former Soviet Union with high levels of sociopolitical oppression
(i.e., Baltic States) have had higher suicide rates than other regions
with less oppression (729). From an economic standpoint, research
on the business cycle and suicide has relied primarily on unemployment
rates, but other indicators include growth rates of the gross domestic
product, the Ayres index of industrial activity, change in the stock
market index, and the rate of new dwelling construction (730). Especially
for men, the data suggest that the greater the prosperity, the lower
the suicide rate, and, conversely, the greater the trend toward
recession, the greater the suicide rate. During periods of high
unemployment, such as the Great Depression, the relationship of
unemployment to suicide is strengthened (731). However, studies
using the Ayres index of industrial activity and monthly suicide
trends have suggested that large swings in industrial production,
such as those that occurred during the 1930s, are needed to influence
the suicide rate (732).
In summary, it is important to ascertain the patient's
employment status as part of the assessment process, since unemployment
may increase suicide risk, whereas employment may offer some protection
against suicide and suicide attempts. However, a patient's
job status should also be considered in terms of other psychosocial
stressors that may be related to job loss, such as financial or
marital difficulties. In addition, there is often a complex interplay
between employment status and psychiatric illness, including substance
use disorder, that may influence treatment planning.
Limited evidence points to religion as a protective factor
against suicide. Pescosolido and Giorgianna (733) used suicide rates
from the National Center for Health Statistics, data on affiliation rates
in various Christian denominations from the National Council of
Churches, and data on Jewish affiliation from the American Jewish
Yearbook to determine whether suicide rates differ according to
religious affiliation. They found that religion affected
suicide rates, with Catholicism, Evangelical Protestantism, and
membership in Church of the Nazarenes being associated with lower
rates and Jewish affiliation producing a small but inconsistent
protective effect. In contrast, various denominations of mainstream
Protestantism tended to be associated with increased suicide rates.
Within specific religious denominations, the strength of religious
belief may also play a role. Maris (394) compared suicide rates
among Catholics and Protestants in Chicago between 1966 and 1968. Scores
on church attendance, perception of religiosity, and influence of
religion were negatively associated with suicidal ideation. After
controlling for the effects of confounding variables such as sex,
marital status, and socioeconomic status, Maris found that the perceived
influence of religion was the most significant correlate of suicidal
ideation. In immigrants from Central America, infrequent church
attendance and low levels of perceived influence of religion were
related to high levels of suicidal ideation (43). Thus, religious
involvement may serve as a protective factor against suicide, either
by helping to buffer acculturative stress (43) or by enhancing social
networks and support (733).
In summary, some evidence suggests that religious beliefs
and the strength of those beliefs may offer protective effects in
relation to suicide risk. At the same time, these protective effects
neither are specific to particular religious denominations nor are
invariably present. Indeed, for some individuals, religious beliefs
or beliefs about death may increase rather than decrease the likelihood
of acting on suicidal thoughts. Consequently, the clinician may
wish to gain an understanding of the patient's specific
religious beliefs and the depth of the patient's religiosity
as well as determine the ways in which these beliefs influence the
patient's conceptions of death and suicide.
+
c) Psychosocial support
Although it is often difficult to distinguish perceived from
objective measures of social support, available data strongly suggest
that the presence of a social network is a powerful and independent predictor
of suicide risk. In particular, those who have (or perceive themselves
to have) supportive interpersonal relationships are at lower risk
for suicide than those without such actual or perceived supports.
Rubenowitz et al. (405) used the psychological autopsy method to
compare 85 persons age 65 years and older who died by suicide with
153 age- and sex-matched living persons selected from the tax roster
in Gothenburg, Sweden. In addition to identifying a powerful influence
of psychiatric disorders, they found that family discord was a significant
risk factor for those who died by suicide (odds ratio
19).
Further, being active in a social club was a significant protective
factor for both men and women. Another recent psychological autopsy
study compared 53 individuals age 55 years and older who had either
died by suicide or made a serious suicide attempt with 269 matched
control subjects (403). Psychiatric illness was again a powerful
predictor of suicide case status, but, in addition, those who died
by suicide had significantly fewer social interactions and significantly
more relationship problems, compared to the control subjects. Turvey
and colleagues (400) used data from the Established Populations
for Epidemiologic Studies in the Elderly database to identify 21
elderly persons who died by suicide over a 10-year follow-up period
and compared those subjects to 420 control subjects matched for
age, sex, and study site. In addition to depressive symptoms, poor perceived
health status, and poor sleep quality, the absence of a relative
or friend in whom to confide was a significant risk factor for late-life
suicide. Finally, Miller (399) compared 30 men age 60 years and
older who died by suicide with 30 men, matched on age, race, marital
status, and county of residence, who died of natural causes. He
reported that the control subjects were significantly more likely
to have had a confidante and that the subjects who died by suicide
had significantly fewer visits with friends and relatives. Thus,
while social support is a complex construct and the data on this factor
come primarily from elderly populations, decreases in measures of
social support appear to increase suicide risk, and, conversely,
increases in social support may serve as a protective factor in relation
to suicide.
+
d) Reasons for living, including children in the
home
An additional protective factor against suicide is the ability
to cite reasons for living, which often reflect the patient's
degree of optimism about life. Malone et al. (231) assessed 84 patients,
45 of whom had attempted suicide, to determine whether "reasons
for living" might protect or restrain patients with major
depression from making a suicide attempt. Depressed patients who
had not attempted suicide were found to have expressed more feelings
of responsibility toward their families, more fear of social disapproval,
more moral objections to suicide, greater survival and coping skills, and
a greater fear of suicide than the depressed patients who had attempted
suicide. Although objective severity of depression and quantity
of recent life events did not differ between the two groups, scores
for hopelessness, subjective depression, and suicidal ideation were
significantly higher for the suicide attempters.
Particularly in women, the presence of children in the home
is an additional factor that appears to protect against suicide.
Hoyer and Lund (26) used data from the Norwegian Central
Bureau of Statistics to prospectively follow 989,949 women over
a 15-year period. During that time there were 1,190 deaths from
suicide, with parous women of all ages having lower relative risks
than nonparous women (relative risk=0.4–0.8,
depending on age). For both premenopausal and postmenopausal women,
a strong linear decrease in relative risk for suicide was found
with an increasing number of children.
Consequently, during the assessment and treatment planning
process, clinicians should discuss reasons for living with at-risk
patients and the need to develop coping skills that may serve as protective
factors during periods of high risk for suicide.
+
e) Individual psychological strengths and vulnerabilities
A number of personality traits and characteristics have been
associated with suicide and suicidal risk and behaviors. Conner
et al. (217) reviewed the literature on psychological vulnerabilities
to suicide, including 46 publications describing 35 distinct case-control
or cohort samples, and found no evidence for a link between suicide
and guilt or inwardly directed anger. They did find that suicide was
consistently associated with five constructsimpulsivity/aggression,
depression, hopelessness, anxiety, and self-consciousness/social
disengagement. Although other factors often moderate the relationships
between these variables and suicide, they are not always interpretable
in the literature because of measurement and definitional issues.
Nonetheless, psychological vulnerabilities likely influence suicide
risk by exacerbating other psychiatric or social risk factors in
individual patients.
A number of other concepts have also been explored in relating
suicide to individual vulnerabilities. For example, Duberstein (423)
used questionnaires to assess personality dimensions in 81 depressed
patients over age 50 and found that individuals who reported lower
levels of openness to new experiences were less likely to report
suicidal ideation. These findings are consistent with other work,
suggesting that elderly persons tend to deny suicidality, whereas
younger persons tend to exaggerate it. These findings may also provide
support for the protective role of expressing suicidal ideation.
Thus, when closed-minded people do come into contact with treatment
services, their psychiatric symptoms may not be as obvious and their
need for treatment may not be appreciated.
Hughes and Neimeyer (422) assessed 79 hospitalized psychiatric
patients, 91% of whom had a principal diagnosis that included
depression, and examined the utility of several cognitive variables as
predictors of suicidal ideation. Level of pessimism, as measured
by the Hopelessness Scale, was the best predictor of subsequent
suicidal ideation and was reliably related to placement on either
one-to-one observation or every-15-minute checks for suicide precautions.
In addition, hopelessness, self-negativity, polarization (all-or-nothing
thinking), and poor problem-solving performance were associated
with suicidal ideation, whereas self-evaluated problem-solving ability
was not. A low level of constriction was related to the intensity
of subsequent suicidal ideation and to later suicide attempts.
Josepho and Plutchik (409) investigated the relationship between
interpersonal problems, coping styles, and suicide attempts in 71
adult psychiatric inpatients. Patients who were hospitalized after
a suicide attempt had more interpersonal problems and also had distinct
patterns of coping methods, including more use of suppression and
substitution and less use of replacement. These coping styles were
also associated with higher scores on a rating of suicide risk.
After controlling for the effect of interpersonal problems, the
authors found that greater suppression, less minimization, and less
replacement were significantly related to increased suicide risk
scores. The higher the risk score, the greater the likelihood that
the patient was admitted to the hospital secondary to a suicide
attempt. Depressed patients also had higher suicide risk scale scores.
Stravynski and Boyer (401) collected data from 19,724 persons
who returned the Quebec Health Survey and tested whether there was
an association between loneliness and suicidal thoughts or behaviors
in the general population. A significant correlation was found between
experiencing suicidal ideation or attempting suicide and living
alone, having no friends, or feeling alone, with psychological distress
being the strongest correlate of suicidal ideation. Of individuals
who were severely distressed and very lonely, 25% reported
serious suicidal ideation or actions. Overall, thoughts of suicide
were reported by 3.1% of the population, and 0.9% had
attempted suicide.
Maser et al. (247) examined the correlations between suicide
and clinical and personality factors in 955 depressed patients who
were followed over 14 years as part of the NIMH Collaborative Program
on the Psychobiology of Depression. During that time, 3.8% died
by suicide and 12.6% attempted suicide. Suicide within
12 months of intake to the study was associated with clinical variables,
including emotional turmoil plus depression in the index episode,
a history of both alcohol and drug use disorders, and meeting the
criteria for antisocial personality disorder. Additional predictors
included hopelessness, delusions of grandeur, indecisiveness, definite
delusions or hallucinations during the index episode, reduced functional
role, dissatisfaction with life, or any prior history of serious
suicide attempts as of the intake episode. Beyond 1 year
after intake, suicide was associated with temperamental factors,
including high levels of impulsivity and shyness and low sanguinity
scores. Suicide attempters and those who died by suicide shared
core characteristics, including previous attempts, impulsivity,
substance abuse, and psychic turmoil within a cycling/mixed
bipolar disorder.
Kaslow et al. (413) conducted an empirical study of the psychodynamics
of suicide among 52 patients hospitalized for a suicide attempt
and 47 psychiatrically hospitalized control subjects with no history
of suicidal behaviors. Overall, 49% of the subjects had
depression, 25% had substance use disorders, and 63% had
a cluster B personality disorder. Individuals who had attempted
suicide were significantly more likely to report childhood loss
combined with adulthood loss. Furthermore, they had more impairment
in their object relations and viewed relationships in a more negative manner,
showing lower levels of individuation and separation. Although self-directed
anger was associated with homicidal ideation, there was little support
for the psychodynamic concepts that depression, self-directed anger,
or ego functioning would be associated with having made a suicide attempt.
In a group of 438 undergraduate college students who ranged
in age from 16 to 65 years, Boudewyn and Liem (734) compared low
and high scorers on a chronic self-destructiveness scale
that measured behaviors such as chronic gambling or unsafe sexual
behaviors that had a potential for later negative consequences.
Overall, those scoring high in self-destructiveness were younger
and reported more childhood and adulthood maltreatment, lower self-esteem,
greater depression, greater externality, less need for control in
interpersonal relationships, and more frequent suicidal and self-injurious thoughts
and acts. These findings suggest that other manifestations of self-destructiveness
should be assessed in the individual evaluation of the suicidal patient
and that childhood and adult maltreatment should be specifically
identified and addressed in the treatment planning process.
Together with extensive clinical observations on individual
strengths and vulnerabilities as they relate to suicidality
(410, 412, 420, 426), research on various psychological dimensions
has demonstrated the need to include such features in assessing
suicide risk. In particular, personality traits such as
aggression, impulsivity, social disengagement and subjective
loneliness, hopelessness, anxiety, low self-esteem (and
protective narcissism), dependence, ambivalence, and depression
may increase risk for suicidal behaviors. Thinking styles such as
closed-mindedness or polarized (either-or) thinking may also augment
risk. If dilemmas are seen only in black-and-white terms, with fewer perceived
options, patients may see no solution to their problems other than
suicide. In addition to personality traits and thinking style, an
individual's psychological needs, when not met, can cause intense
psychological pain, contributing to a suicidal state. Early trauma
and loss may thwart the development of healthy coping skills. In
addition, individual perceptions of interpersonal supports, particularly
subjective perceptions of loneliness, may also contribute to suicide
risk. Thus, in weighing the strengths and vulnerabilities of the
individual patient and developing and implementing a plan of treatment,
it is helpful to assess the patient's past response to
stress, vulnerability to life-threatening affects, available external
resources, perceived sense of loneliness, fantasies about death, and
capacity for reality testing and for tolerating psychological pain.
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8. Degree of suicidality
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a) Presence, extent, and persistence of suicidal
ideation
Suicidal ideation is common, with an estimated annual incidence
of 5.6% (2). Kessler et al. (427) examined the lifetime
prevalence of suicidal ideation and suicide attempts in a sample
of 5,877 individuals age 15–54 years as part of the National
Comorbidity Survey. The estimated lifetime prevalences of suicidal
ideation, plans, and attempts were 13.5%, 3.9%,
and 4.6%, respectively. The cumulative probability of moving
from suicidal ideation to an unplanned attempt was 26%.
The corresponding cumulative probability for transitioning from
suicidal ideation to suicidal plans was 34%, with a 72% cumulative
probability for going from a suicide plan to an attempt. About 90% of
unplanned attempts and 60% of planned first attempts occurred
within 1 year of the onset of suicidal ideation, suggesting a need
for aggressive aftercare and attention to potentially modifiable
risk factors in individuals with suicidal ideation.
Longitudinal studies also demonstrate an increased risk of
eventual suicide in patients with suicidal ideation. Among 6,891
psychiatric outpatients who were followed for up to 20 years, Brown
et al. (78) found that patients' scores on clinician-administered
measures of current suicidal ideation and depression were most closely
associated with eventual suicide. Fawcett et al. (79), using a case-control
method to determine time-related predictors of suicide among 954
patients with major affective disorder, examined suicidal ideation
as one possible predictor of actual suicide over a 10-year period.
They found that the presence of suicidal ideation was associated
with an increased risk for suicide on a long-term basis but not
within the first year after study entry.
Others have examined the association between eventual suicide
and suicidal ideation at its worst using the Scale for Suicide Ideation–Worst
(SSI–W) (428). In a group of 3,701 outpatients in which there
were 30 suicides, patients who scored in the high-risk category
on the SSI–W had a rate of later suicide that was 14 times
greater than that of the patients in the low-risk category. After
controlling for the effects of other factors, the investigators
found that only the SSI–W score, and not the scores on
measures of current suicidal ideation or hopelessness, was associated
with future suicide (428). Consistent with the findings of Clark
and Fawcett (273), the authors concluded that retrospective report
of suicidal ideation at its worst may be a better predictor of suicide
than currently reported suicidal ideation.
Intuitively, since suicidal ideas would be expected to precede
suicidal intent or suicidal acts, they may serve as a guide for
clinicians in identifying and addressing suicide risk. These studies
also suggest that past as well as current suicidal ideation is relevant
to the assessment process. However, since the vast majority of individuals
with suicidal ideation do not die by suicide, additional factors are
likely to be modulating suicide risk even in individuals with suicidal
ideas.
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b) Presence of a suicide plan and availability of
a method
As noted earlier, about one-third of individuals with suicidal
ideas go on to develop a suicide plan, and about three-quarters
of those with a plan eventually make a suicide attempt. Other individuals,
however, go on to attempt suicide in an unplanned manner. Thus,
the presence of a suicide plan signifies that the risk of a later
attempt is increased, but it by no means indicates that an attempt
will occur or even the time frame within which an attempt may occur.
By the same token, the absence of a suicide plan does not eliminate
suicide risk. In general, however, the presence of a specific plan
involving an available method is associated with a greater degree
of risk for suicide. In addition, availability of methods with relatively
high levels of lethality may increase the likelihood that a suicide
attempt, either planned or impulsive, will result in suicide.
A number of studies have examined population-based trends
in suicide rates as they relate to the availability of specific
methods for suicide. Ohberg et al. (735), for example, evaluated
trends in suicide rates and availability of methods used for suicide
in Finland from 1947 to 1990. For both sexes, the overall suicide
rate in Finland rose significantly in that time period, but method-specific rates
of suicide varied. For example, the rate of suicide by using the
highly lethal pesticide parathion decreased after its availability
was restricted, but this decrease was offset by an increased rate
of suicide by other methods. Before 1962, most suicides occurred
by hanging or drowning, but after 1963, there was a rapid increase
in the use of firearms. Coincident with increases in the availability of
antidepressants and neuroleptics, the rates of suicide by overdose
of these medications increased. There was a high number of overdoses
of tricyclic antidepressants, which accounted for most of the deaths
attributed to antidepressants. On the other hand, the number of
overdose deaths attributed to nontricyclic antidepressants decreased,
despite increased availability, and the number of overdose deaths
attributed to barbiturates remained stable despite reduction in
their availability.
Gunnell et al. (436) investigated method-specific trends in
suicide between 1950 and 1975 in England and Wales. In the 1950s
and early 1960s, domestic gas poisoning was the most frequently used
method of suicide among men and women, accounting for one-half of
all suicides. Changes in domestic gas supply and manufacture resulted
in a reduction in its carbon monoxide content and thus lethality,
and overall suicide rates declined in men and women of all ages.
In women and younger men (younger than age 55 years), the effects
of these reductions on overall suicide rates were partially offset
by a rise in the rates of drug overdose deaths, but there were no
immediate increases in the use of other suicide methods. In older
men, a reduction in the rate of suicide by gassing was accompanied by
only a slight increase in the rate of suicide by overdose as well
as reductions in rates of suicide by using all other methods.
Marzuk et al. (437) investigated the relationship between
the availability of lethal methods of injury and suicide rates by
prospectively classifying lethal methods according to their accessibility
in the five counties of New York City over a 4-year period and then
comparing the age- and gender-adjusted method-specific suicide rates
of the counties. During the study period, there were a total of 2,820
suicides, a rate of 9.81 per 100,000 persons. The study found marked
differences in overall crude suicide rates among the five counties,
which ranged from 15.27 per 100,000 persons in Manhattan to 5.58
per 100,000 persons in Staten Island. The counties had similar suicide
rates involving methods that were equally accessible to all persons
in each county (e.g., hanging, laceration, suffocation, and burns)
as well as methods that were accessible to a smaller but similar
proportion of the population in each county (e.g., firearms and
drowning in waterways). Virtually all of the differences in overall
suicide risk among the counties were explained by methods that were
differentially available, such as fall from height, overdose of
prescription drugs, and carbon monoxide poisoning (explained by
access to private parking). The availability of a greater variety
of alternative lethal methods in some counties did not suppress
the rates of use of other methods, and a relative lack of the availability of
a specific method did not result in a comparative increase in the
rates of use of alternative methods that were available, as the
substitution hypothesis would have predicted. Thus, restriction
of the availability of a method may reduce its use for suicide,
but other methods may tend to be used instead. At the same time,
the accessibility to and lethality of particular methods of suicide
may have definite effects on the overall suicide rate.
In the United States, firearms constitute the most common
method for suicide (736, 737). Fox et al. (738) used mortality data
for 1979–1994 from the Wisconsin Center for Health Statistics
and the U.S. Census Bureau population estimates for Wisconsin to
describe trends for firearm-related suicides in that state. During
that period, there were an average of 588 suicides annually, with
firearms eclipsing all other methods combined as the most common
method of suicide in the 1980s. Between 1981 and 1992, the proportion
of firearm suicides increased from 48% to 57%.
While the overall suicide rate remained unchanged over the period,
the firearm suicide rate increased 17% in all sex, race,
and age categories. Among males, the firearm-related suicide rate
rose by 13% during the study period, while the rate of
suicide by all other methods combined fell 12%. In comparison,
among females, the firearm-related suicide rate rose 20%,
and the rate of suicide by all other methods fell 26%.
Kaplan and Geling (434) investigated the sociodemographic
and geographic patterns of firearm suicides in the United States
using mortality data from the National Center for Health Statistics Mortality
detail files and death certificate files reported by each state
from 1989 to 1993. During this time period, 59.2% of the
139,566 suicides were by firearms. Married persons had the lowest
rate of any form of suicide across all race, sex, and age groups.
The adjusted odds of using firearms increased with age among men
and decreased with age among women. Widowed men and married women
had the highest odds of using firearms, and the odds of using a
firearm for suicide were also high among those without college education,
those who had lived in nonmetropolitan areas, and those who had lived
in the East South Central and West South Central geographic divisions.
Rates of nonfirearm suicides were higher than firearm suicides everywhere
but in the regions of the South. Thus, the likelihood of firearm
suicide varied significantly across sociodemographic and geographic
subgroups of the U.S. population and paralleled variations in gun
ownership, suggesting that regional cultural factors may account
for differential rates in suicidal behavior involving firearms.
In addition to population-based data on firearm availability
and suicide risk, some data also suggest an effect at an individual
level. Brent et al. (438) performed a case-control study to determine
the relationship between the presence of guns in the home, the type
of gun, the method of storage, and the risk of suicide among adolescents.
Forty-seven adolescents from the community who died by suicide were
compared with two control groups from a psychiatric hospital: 47
patients who attempted suicide but survived and 47 patients who
had never attempted suicide. The study found that guns were twice
as likely to be found in the homes of those who died by suicide
as in the homes of the suicide attempters or psychiatric control
subjects. There was no significant difference in association with
suicide between handguns and long guns, and there was no difference
in the methods of storage of firearms among the groups. The authors
concluded that the availability of guns in the home, independent
of the type of firearm or storage method, appears to increase the
risk for suicide, at least among adolescents.
In summary, the presence of a suicide plan and the availability
of a method for suicide increase risk and are important issues to
address as part of the suicide assessment. Since firearm-related
suicides account for a significant fraction of suicides in the United
States, the presence and availability of firearms are also an important
line of inquiry in a suicide risk assessment. A debate remains over
whether a reduction in the availability of a particular method of
suicide reduces overall risk, although most evidence indicates that
restrictions on the availability of particular types of popular
methods result in a lower overall suicide rate. At the individual
level, reducing access to specific suicide methods may also be indicated.
See Section II.C.2, "Elicit the Presence or Absence of
a Suicide Plan", for additional
discussion of inquiries, removal, and documentation issues related
to firearms and the suicidal patient.
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c) Lethality and intent of self-destructive behavior
In addition to being increased by the presence of suicidal
ideation, a suicide plan, or an available suicide method, suicide
risk is also influenced by the patient's subjective expectation
and desire to die as a result of a self-inflicted injury. This factor
has generally been termed suicidal intent, although the patient's
subjective expectation may or may not correspond to the lethality
of an attempt made by using a given method. Other facets of a suicide
plan or attempt that are often considered when estimating suicidal
intent include the severity and potential lethality of the suicide
attempt or aborted suicide attempt, the patient's degree
of premeditation, whether precautions were taken to avoid intervention
or discovery, and whether the patient's intentions were
communicated to others (263, 433, 440).
Several studies have longitudinally assessed the influence
of suicidal intent on later suicide risk. In a group of 500 patients
who had completed a scale measuring suicidal intent after an episode
of self-injury, Pierce (441) found that the seven individuals who
had died by suicide by the time of a 5-year follow-up tended to
have high suicidal intent scores at the time of their initial self-injury.
In addition, individuals with increasing levels of suicidal intent
with repeated self-injury appeared to be at greater risk for further
repetition of self-injury (739). Suokas et al. (271) also conducted
a longitudinal assessment of the effect of suicidal intent on suicide
risk. They found that 68 (6.7%) of 1,018 deliberate self-poisoning
patients had died by suicide by 14-year follow-up. Risk factors
for suicide included being male, having previous psychiatric treatment
or suicide attempts, having a somatic disease, and having a genuine
intent to die at the time of the index self-poisoning.
Thus, for any patient with suicidal ideation, it is important
to determine suicidal intent as part of the assessment process.
In addition, for any patient who has made a prior suicide attempt,
the level of intent at the time of the previous attempt should be
determined.
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9. Weighting of risk factors in suicide prediction
As noted previously, it is impossible to accurately predict
suicide. Nevertheless, given the large number of risk factors and
protective factors that can affect the likelihood of suicide, a
number of statistical models have been developed to attempt to pinpoint
which patients may be at greatest risk. In a longitudinal study
by Pokorny (160) that followed 4,800 subjects (4,691 males and 109
females) over a 5-year period, stepwise discriminant analysis was
used to select a weighted combination of predictive variables from
the identified high-risk characteristics, i.e., being a white male;
being single; having a diagnosis of affective disorder, schizophrenia,
or alcoholism; having made a previous suicide attempt; or having
personality disorder-related traits such as manipulativeness and
hostility. This method was able to correctly identify 30 of the
67 subjects who died by suicide but also falsely predicted suicide
in 773 individuals. Thus, while it may be possible to identify a
high-risk group of patients who warrant more detailed clinical screening,
it may not be possible to identify the particular individuals at
greatest risk.
Goldstein et al. (740) also used a statistical model that
incorporated multiple risk factors for suicide and applied it in
a group of 1,906 patients with affective disorders who were admitted
to a tertiary care hospital and were followed longitudinally. The
identified risk factors included the number of prior suicide attempts,
the presence of suicidal ideation on admission, gender, outcome
at discharge, and a diagnosis of either bipolar affective disorder
(manic or mixed type) or, in individuals with a family history of
mania, unipolar depressive disorder. The full statistical model,
however, was unable to identify any of the patients who died by
suicide, highlighting the difficulty of estimating suicide risk
with such methods.
In general, statistical models may be valuable in the epidemiological
and research arenas by identifying factors that distinguish high-risk
populations of patients. They can also suggest clinically important
risk factors that, if identified, are potentially amenable to treatment.
However, given the low base rates of suicide in the population,
accurate prediction of suicide remains impossible, regardless of
the complexity of the statistical model used. Consequently, the
psychiatric assessment, in combination with clinical judgment, is
still the best tool for assessing suicide risk. In addition, intervention
must be based not on the simple presence of risk factors as identified
by statistical models but on the interaction of those factors with
the individual patient's personal and clinical manifestations and
the clinician's assessment of the patient's
risk at that particular point in time.
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B. Psychiatric Assessment Techniques
A wide variety of self-report and clinician-administered scales
are available that measure various aspects of suicidal thoughts
and behaviors as well as symptoms associated with suicide. These
scales are reliable and have adequate concurrent validity, and they
may have application as research tools. However, their usefulness
and generalizability in clinical practice are questionable. Most
of the scales have been tested in nonrepresentative samples composed
of college students or psychiatric patients and have not been adequately
tested in important subpopulations of patients, such as elderly
patients, minority group patients, and patients in common clinical
settings, including emergency departments or primary care practices. Few
of these scales have been tested in prospective studies, and those
that have been tested have shown very low positive predictive validity
and high rates of false positive findings. As a result, for the
practicing clinician, these rating scales are primarily of value
in learning to develop a thorough line of questioning about suicide
(see Section II.C.4, "Understand the Relevance and Limitations
of Suicide Assessment Scales").
It is for this reason that the specific rating scales will be reviewed
briefly here. In addition, information about the scales may be helpful
in interpreting the findings of other studies discussed in this
guideline.
The Scale for Suicide Ideation (8) is a 19-item, clinician-administered
scale that takes approximately 10 minutes to administer and was
designed to quantify the intensity of current and conscious suicidal
intent by assessing the extent and characteristics of suicidal thoughts;
the patient's attitude toward suicidal thoughts; the wish
to die; motivations, deterrents, and plans for a suicide attempt; and
feelings of control and courage about a suicide attempt. Although
standardized for use with adult psychiatric patients, the Scale
for Suicide Ideation has been used in a variety of settings and
has high levels of internal consistency and interrater reliability.
Scores on the Scale for Suicide Ideation have been correlated with
the self-harm item of the Beck Depression Inventory and have been
shown to discriminate between depressed outpatients and patients
hospitalized for suicidal ideation, despite similar levels of depression
in the two groups (8), suggesting that the scale measures something
above and beyond depression alone. Although the Scale for Suicide
Ideation is one of the few instruments with a demonstrated positive
predictive validity for suicide, its positive predictive value is
only 3%, and it has a high rate of false positive findings
(78). A number of modified versions of the Scale for Suicide Ideation
exist, including a 21-item self-report version (741) and a measure
of suicidal ideation at its worst, the SSI–W, which is
also a 19-item, clinician-administered instrument (428).
The Suicide Behavior Questionnaire (SBQ) is a self-report
measure of suicidal thoughts and behaviors that is significantly
correlated with the Scale for Suicide Ideation (10). The original
four-item version has adequate internal consistency, high test-retest
reliability, and takes less than 5 minutes to complete. A 14-item
revised version (SBQ-14) is a more comprehensive measure of suicidal
attempts, ideation, and acts and includes items on suicidal ideation,
future suicidal ideation, past suicide threats, future suicide attempts,
and the likelihood of dying by suicide in the future. Although the
SBQ has high internal reliability and an ability to differentiate
between clinical and nonclinical samples (10), the positive predictive
validity of the SBQ is not known.
The Suicide Intent Scale (9) is a 20-item clinician-administered
scale that has high internal and interrater reliabilities and that
quantifies a patient's perceptions and verbal and nonverbal
behaviors before and during a recent suicide attempt. It includes
questions about circumstances surrounding an attempt, the method
and setting of the attempt, the patient's perception of
the lethality of the method, expectations about the probability
of rescue, premeditation of the attempt, and the purpose of the
attempt. Although scores on the Suicide Intent Scale are associated
with the lethality of the method, the scale is unable to distinguish
between those who attempted suicide and those who aborted their
suicide attempts, and it does not predict death by suicide (10).
The Reasons for Living Inventory (407) is a self-report instrument
that takes approximately 10 minutes to administer and uses 48 Likert-type
scale items to assess beliefs and expectations that would keep one
from acting on suicidal ideas. This scale has high internal validity
and reliability and moderately high test-retest reliability. It
is moderately correlated with the Scale for Suicide Ideation and
the Beck Hopelessness Scale and is able to differentiate between
inpatients and control subjects as well as between suicide attempters
and those with suicidal ideation alone (10).
A number of other scales have been devised to assess suicidality.
Among them are the Risk-Rescue Rating, which assesses lethality
of a suicide attempt and the level of suicidal intent (433), and
the Suicide Assessment Scale, which assesses suicidality over time
in the five areas of affect, bodily state, control and coping, emotional
reactivity, and suicidal thoughts and behaviors (742). Other more general
rating scales include items that have also been used in assessing
suicide risk. For example, the Thematic Apperception Test has been
used to indicate dichotomous thinking as a risk factor for suicide
(743), and the General Health Questionnaire includes a subset of
four items that can be used to assess suicidal ideation (744). Based
on the theory that psychological pain (or psychache) may be related
to suicide, Shneidman (745) developed a psychological pain assessment
scale that uses pictures to assess the patient's unmet
psychological needs, providing a measure of the introspective experience
of negative emotions that may relate to suicidality. By using the
scale to explore a patient's perception of psychological
pain, clinicians may be able to identify the patient's
coping mechanisms and ego strengths. Use of this scale may also
help the clinician assess the patient's mental
anguish and address the psychological needs that the patient views
as important and unmet.
In addition, because depression and hopelessness are risk
factors for suicide, corresponding rating scales are often used
as indicators of suicide risk. The Beck Hopelessness Scale is a
self-report measure consisting of 20 true-false statements that
assess positive and negative beliefs about the future that are present
during the week before administration (712). The Beck Hopelessness
Scale demonstrates high internal validity, adequate test-retest
reliability, and moderate to high correlations with clinicians' rating
of hopelessness (10). In addition, it is one of the only scales
that has demonstrated positive predictive validity (10). In a 10-year
prospective study of hospitalized patients with suicidal ideation,
the Beck Hopelessness Scale was able to distinguish those who died
by suicide and those who did not (222). Nonetheless, its positive
predictive value is only 1% (78, 713), and its rate of
false positive findings is high (221).
The most frequently used depression scales for suicide assessment
are the Hamilton Depression Rating Scale and the Beck Depression
Inventory. As measured by these scales, higher levels of depression
have been associated with suicide in long-term studies of psychiatric
outpatients (78, 221). In addition to being associated with the
overall Beck Depression Inventory score, suicide has also been associated
with specific inventory items. For example, the Beck Depression
Inventory item that measures pessimism has been shown to differentiate
between patients who die by suicide and those who do not (222),
and the suicide item, which has possible responses on a 4-point
scale ranging from "no thoughts of killing myself" to "would
kill myself if I had the chance," is also associated with
increased suicide risk (10). The corresponding suicide
item in the Hamilton Depression Rating Scale measures
suicidal behavior on a scale of 0 (absent) to 4 (attempts suicide),
has high interrater reliability, and is similarly associated with
increased suicide risk (10).
Thus, there are a variety of rating scales that are useful
for research purposes and that may be helpful to clinicians in tracking
clinical symptoms over time and in developing a thorough line of questioning
about suicide and suicidal behaviors. At the same time, because
of their high rates of false positive and false negative findings
and their low positive predictive values, these rating scales cannot
be recommended for use in clinical practice in estimating suicide
risk.
Multiple studies, reviewed elsewhere (366, 746, 747), have
suggested that suicidal behaviors may be associated with alterations
in serotonergic function. As a result, a number of biological markers of
serotonergic function, including cerebrospinal fluid (CSF) levels
of monoamine metabolites such as 5-hydroxyindoleacetic acid (5-HIAA),
have been suggested for use in assessing suicide risk. Traskman
et al. (748) compared suicide attempters (N=30) to normal
control subjects (N=45) and found that the attempters,
particularly those who had made more violent suicide attempts, had significantly
lower CSF 5-HIAA levels that were independent of psychiatric diagnosis.
Subsequent longitudinal follow-up of 129 individuals after a suicide
attempt showed that 20% of those with CSF 5-HIAA levels
below the median had died by suicide within 1 year (748). Serotonergic
function, as measured by the response of prolactin to the specific
serotonin releaser and uptake inhibitor d-fenfluramine,
was also found to be blunted in medication-free patients with DSM-IV
schizophrenia who had attempted suicide, compared with nonattempters
and healthy control subjects (749).
Hyperactivity of the hypothalamic-pituitary-adrenal (HPA)
axis has been associated with suicide since 1965, when Bunney and
Fawcett (750) reported three suicides occurring in patients with
very high levels of urine 17-hydroxycorticosteroids. Subsequent
literature has shown evidence of hypertrophic adrenal glands (751–753)
and elevated levels of brain corticotropin-releasing hormone (754, 755)
in individuals who died by suicide. The dexamethasone
test (DST) has also been used to study whether HPA dysfunction is
associated with a type of depressive illness that is likely to end
in suicide. In 234 inpatients with unipolar depression, 96 had abnormal
DST results, and of these, four died by suicide, in contrast to
one suicide death in the group with normal DST results (756). In
a subsequent longitudinal study of hospitalized patients
with either major depressive disorder or the depressed type of schizoaffective
disorder, survival analyses in the 32 patients with abnormal DST
results showed an estimated risk for eventual suicide of 26.8%,
in contrast to an estimated risk of 2.9% in the 46 patients
with normal DST results (757).
On the basis of a series of population studies (758) and a
study by Ellison and Morrison (759) showing associations between
low cholesterol levels and increased rates of suicide and violent
death, cholesterol levels have also been suggested as a putative
biological marker for suicidal behaviors. Fawcett et al. (760) reported
decreased mean levels of cholesterol in a sample of 47 inpatients
who died by suicide. However, Tsai et al. (82) did not find decreased
cholesterol levels in a chart-review study of 43 bipolar disorder
patients who died by suicide. A case-control study found significantly lower
mean cholesterol levels in a group of 100 psychiatric inpatients
who had attempted suicide, compared with a matched group of patients
hospitalized for physical illness (761). No correlation existed
between cholesterol levels and ratings of depression or suicidal
intent, and a significant negative correlation between cholesterol
levels and self-reported levels of impulsivity was seen across the groups.
In a group of 783 outpatients consecutively admitted to a lithium
clinic, Bocchetta et al. (762) found a significantly higher likelihood
of a history of violent suicide attempts and of suicide in first-degree
relatives among men in the lowest quartile of cholesterol levels,
compared with men with higher cholesterol levels. Alvarez (763)
also reported an association of violent, but not nonviolent, suicide
attempts with low cholesterol levels. However, the clinical importance
of these findings is unclear, since the use of statin drugs to reduce
cholesterol does not appear to be associated with any increase in
violence, aggressiveness, unhappiness, accidents, or suicide (764).
Overall, a great deal of evidence suggests that specific biological
markers may relate to suicidal behaviors, perhaps through links
to impulsivity or aggression. Nevertheless, while intriguing and potentially
useful in further understanding the biological underpinnings of
suicidal behaviors, none of these putative biological markers are
sensitive or specific enough to recommend their use in routine screening
or in clinical practice.
Homicide-suicide, which has often been referred to in the
literature as murder-suicide, is relatively uncommon yet
essential to keep in mind when assessing individuals at risk for
suicidal ideation or behaviors. Suicide is an act of violence toward
one's self that may also be an expression of anger or other-directed
violence toward another person. After reviewing the literature on
risk factors for suicide and for violence, Plutchik (765) proposed
a theoretical model that numerically weights a series of variables
in order to systematically relate suicide risk to the risk of violence.
Of 37 variables noted to be risk factors for violence, 23 were also
risk factors for suicide. Another 17 variables were identified as
protective factors that decreased the risks of both suicide and
violence. Thus, some correlates of suicidal behavior are also associated
with violence, an overlap that may contribute to homicide-suicides.
Epidemiologically, homicide-suicide occupies a distinct but
overlapping domain with suicide, domestic homicide, and mass murder
(20). Although definitions of homicide-suicide vary (20, 766, 767),
in general, the two acts occur in close temporal proximity, often
with the suicide occurring within seconds or minutes of the homicide.
The annual incidence in the United States is difficult to determine
but has been estimated to be 0.2–0.9 per 100,000 persons,
without significant changes over the past several decades (19, 20).
It is likely that about 1.5% of all suicides and 5% of
all homicides in the United States occur in the context of homicide-suicide.
Homicide-suicide between spouses or lovers represents
the majority of homicide-suicides in the United States (19, 766–768), and
shooting is the method used in almost all cases (768).
The principal perpetrators of homicide-suicide are young men
with intense sexual jealousy or despairing elderly men
with ailing spouses (19, 767, 768). In the latter group, associated
symptoms of depression are often compounded by financial stressors,
resulting in despair (768). Histories of violence and domestic abuse
are common (19, 768), as is substance use (19, 768, 769), although perpetrators
tend to be less deviant and have less previous criminal involvement
than the typical homicide perpetrator (768). Ninety percent of all
homicide-suicide incidents involve only one victim, and the principal
victims are female sexual partners or consanguineous relatives,
usually children (20, 768). Although infanticide is an extremely
rare phenomenon (766), mothers who develop postpartum psychosis
need to be assessed for suicidal and homicidal impulses directed
toward their newborn or other children (27). The risk is especially
high in the first postnatal year, when the suicide risk is increased
70-fold (27). Under all of these circumstances, the common theme
is the perpetrator's overvalued attachment to a relationship,
which leads him or her to destroy the relationship if it is threatened
by real or imagined dissolution.
The management of patients assessed to have both suicidal
and homicidal impulses should parallel that for either
type of risk alone. In particular, in addition to identifying risk
factors and protective factors, careful attention should be given
to previous hospitalizations, psychosocial stressors, past and current
interpersonal relationships, and comorbid factors such as the use
of alcohol or other substances. It is also crucial to inquire about
firearms and to address the issue with the patient and others if
firearms are accessible (see Sections II.E.8.b, "Presence
of a Suicide Plan and Availability of a Method" and V.C, "Communication With Significant
Others"). Although the legal
duty for psychiatrists to warn and protect endangered third parties
varies in each state, clinical interventions should endeavor to
protect endangered third parties whenever possible.
As for psychopharmacologic management, questions have been
raised about the effects of fluoxetine and other serotonin reuptake
inhibitor (SRI) antidepressants on violence and suicide. Tardiff
et al. (770) analyzed data from the New York City medical examiner's
office on all 127 homicide-suicides that took place in that city
from 1990 to 1998. Only three of the perpetrators (2.4%) were
taking antidepressants. Given the fact that SRIs were widely prescribed
in the 1990s, this finding provides no support for the view that
SRI treatment is associated with violence or suicide.
In summary, data on homicide-suicide are limited but suggest
that patients who present with a recent suicide attempt, have a
suicide plan, or voice suicidal ideation should be evaluated for
their risk of violent or homicidal behavior. Similarly, patients
who present with recent violent behavior or homicidal ideation should
be evaluated for suicidal behavior. Clinicians should also assess
whether obsessive or delusional jealousy or paranoia is present,
especially if such symptoms are comorbid with depression in a patient
with a history of domestic abuse. In addition, in older individuals, clinicians
should assess for signs of depression or dependency in a spouse
whose partner's medical condition is deteriorating. Although
less common among homicide-suicide perpetrators, mothers with postpartum
psychosis or depression also require careful assessment. Key interventions
include treating the mental illness, removing firearms and other
lethal methods, and providing assistance with psychosocial supports
and social services.
Suicide pacts, defined as a mutual arrangement between two
people to kill themselves at the same time, account for a very small
percentage of suicides (0.3%–2.4%, depending
on the study) (771–773). As with homicide-suicides, the
majority of suicide pact deaths occur in married couples. Social isolation
is common, and rates of psychiatric illness, particularly depression,
are high in one or both decedents (771–773). Other risk
factors also parallel risks for suicide, in general, suggesting
that the best approach to detection of suicide pacts is a thorough
suicide assessment with attention to psychiatric and psychosocial
factors.
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3. Deliberate self-harm
Deliberate self-harm is a phenomenon related to but distinct
from attempted suicide. Although deliberate self-harm behavior can
encompass suicide attempts, it also includes self-mutilation, such as
burning, cutting, and hair pulling, that is not associated with
fatal intentions (520). Three categories of self-mutilation have
been described. Major self-mutilation is infrequent and is usually
associated with psychosis or intoxication. Stereotypic self-mutilation
is repetitive and driven by a biologic imperative to harm the self.
Superficial to moderate self-mutilators use self-harming behaviors
as a way to relieve tension, release anger, regain self-control,
escape from misery, or terminate a state of depersonalization (520).
Extreme forms of self-harm are very rare and often accompany religious
or sexual delusions in patients with prominent psychosis or depression
(520). Individuals with a history of deliberate and particularly
repetitive self-harm also show significantly greater degrees of
impulsiveness (774) and are likely to have a diagnosis of borderline
personality disorder (521). In addition, repetitive self-mutilators
who become depressed and demoralized over their inability to stop
the behavior may be at increased risk for suicide attempts (520).
From a clinical standpoint, it is essential to recognize that
a past or current history of nonlethal self-harming behaviors does
not preclude development of suicidal ideation or plans or preclude suicide
attempts with serious intent and lethality. For example,
Soloff et al. (521) examined aspects of self-mutilation and suicidal
behavior in 108 patients with borderline personality disorder and
found evidence of self-mutilation in 63% and
suicide attempts in 75.7% of the patients. Compared to patients
without self-mutilation, those with self-mutilation were significantly
younger and had more serious suicidal ideation, more recent suicide
attempts, and more symptoms, including psychosis and depersonalization.
Stanley et al. (251) compared 30 suicide attempters with cluster
B personality disorders and a history of self-mutilation to 23 matched
suicide attempters with cluster B personality disorders but no prior
self-mutilation. While the two groups did not differ in the objective
lethality of their suicide attempts, those with a history of self-mutilation perceived
their suicide attempts as less lethal, with a greater likelihood
of rescue and with less certainty of death. Suicide attempters with
a history of self-mutilation had significantly higher
levels of other symptoms, such as depression, hopelessness, aggression,
anxiety, and impulsivity, that are associated with an increased
risk of suicide. Furthermore, self-mutilators had higher and more
persistent levels of suicidal ideation than those without a history
of self-mutilation. These findings highlight the importance of distinguishing
self-mutilatory behaviors from other, more lethal forms of deliberate
self-harm. In addition, they underscore the need for a thorough
suicide assessment and an appreciation of the multiple determinants
of suicide risk in individuals with histories of repetitive deliberate
self-harm.
Evidence for reduction of suicidal risk with specific forms
of psychiatric treatment is very limited. The most secure research
support pertains to psychopharmacological treatments for major affective and
psychotic disorders, but even this evidence should be considered
preliminary. Moreover, support for reduced suicide risk with psychopharmacological
treatment is limited to lithium in various forms of recurrent major
affective disorders and clozapine in chronic psychotic illnesses.
Support for reduction of suicide risk with antidepressants and mood-stabilizing
anticonvulsants is very limited and is at best only suggestive and
inconclusive.
A growing number of antidepressant drugs have been shown to
be clinically effective in the treatment of acute, recurrent, and
chronic depressive illness and a number of anxiety disorders (526). Moreover,
nontricyclic, non-SRI antidepressants are relatively safe and present
virtually negligible risks of lethality on overdose (526). Since
suicidal behavior is strongly associated with depressive illnesses
and some forms of anxiety, treatment with antidepressants should
plausibly be associated with reduced suicide rates. However, the
available evidence remains surprisingly inconclusive that any type
of antidepressant or antianxiety treatment is associated with lowering
of risk for suicidal behavior (69, 526, 528–532, 563).
Specific types of antidepressants vary greatly in their potential
lethality on overdose and relative safety for use by potentially
suicidal patients. All tricyclic antidepressants and monoamine oxidase
inhibitors (MAOIs) are potentially lethal on acute overdose (526, 556, 557), contributing to their currently limited clinical use,
particularly for potentially suicidal patients. Most newer antidepressants, including
bupropion, mirtazapine, and nefazodone, and the SRIs have very low
lethality in acute overdose (526). The finding of Kapur et al. (557)
that tricyclic antidepressants were associated with greater rates
of suicide than the nontricyclic antidepressants fluoxetine and
trazodone was likely due to the differential toxicity of these agents
in overdose, since rates of suicide attempts among patients taking
either of the two types of medication were comparable. With the
preferential use of nontricyclic, non-MAOI antidepressants by primary
care physicians as well as psychiatrists (526), antidepressant overdoses
are less often associated with suicide than they were formerly (775, 776), although methods of suicide also may be shifting from overdoses
to more lethal alternatives (735, 777).
Coincident with wide clinical acceptance of the safer, nontricyclic,
non-MAOI antidepressants since the late 1980s, suicide rates in
several countries, regions, or subpopulations have fallen appreciably
(69, 531, 532, 549, 550), although international average suicide
rates have remained relatively flat for many years, and rates have
risen in some subgroups (69, 529, 775, 778, 779). Even stable suicide
rates, however, may suggest some improvement in suicide prevention
in view of the epidemiological evidence of rising incidence (or
greater recognition and diagnosis) of major affective illnesses
over the past several decades (694, 780, 781). Since multiple
studies have suggested that many depressed individuals do not receive
psychiatric intervention or effective antidepressant treatment
prior to suicide (206, 267, 578, 782–784), further decreases
in suicide rates might occur as a result of improved recognition
and treatment of depression.
Longitudinal follow-up data also suggest that long-term antidepressant
treatment is associated with a decreased risk of suicide. Angst
et al. (74) followed 406 patients with affective disorders for 34
to 38 years after an index psychiatric hospitalization
and found that standardized mortality rates for suicide were significantly
lower in patients with unipolar depressive disorder as well as in
patients with bipolar disorder during long-term treatment with antidepressants
alone, with a neuroleptic, or with lithium in combination with antidepressants
and/or neuroleptics. This lowering of suicide mortality was
particularly striking in light of the fact that the treated patients
were more severely ill than the patients who did not receive long-term
medication therapy.
Data from one double-blind placebo-controlled study (785)
suggested that suicide attempts may also be reduced by long-term
antidepressant treatment. In a 1-year trial in nondepressed individuals with
repeated suicide attempts, paroxetine treatment was associated with
a decreased likelihood of an additional suicide attempt. Although
many of the patients in the study met the criteria for a cluster
B personality disorder, paroxetine was significantly more effective
in those who met fewer of those criteria.
More specific information is available from therapeutic trials
of antidepressants in depressed subjects, including data on suicides
and serious suicide attempts. These findings were recently evaluated in
a meta-analysis (533, 562) based on 13 pertinent reports that appeared
between 1974 and 2000 and had data suitable for analysis (534–546).
A majority of the studies (eight of 13) involved double-blind designs
and random assignment to treatment with a then-experimental or standard
antidepressant, to placebo treatment, or to an untreated comparison
condition in a total of 37 separate treatment arms; several of the
studies included pooled data from multiple trials. A total of 258,547
patient-subjects were included, with a total of 189,817 person-years
of risk exposure encompassing short-term efficacy trials as well
as reasonably long-term treatment trials. Based on these reports,
pooled rates of suicide or suicide attempts by type of treatment
suggested that antidepressant treatment is associated with a substantial,
approximately fourfold lowering of risk for suicidal behaviors (533).
However, owing mainly to the large variance in outcomes between
studies, none of the effects of antidepressants in reducing rates of
suicidal behaviors reached statistical significance. When comparisons
were made among specific types of antidepressants, there was a substantial
difference between tricyclic and SRI antidepressants, suggesting
the possible superiority of tricyclics, but this effect also failed
to reach statistical significance.
Using data from studies in the FDA database of controlled
clinical trials for antidepressant treatment of depressed patients,
Khan et al. (548) used meta-analysis to compare rates of
suicide in patients treated with SRI antidepressants, non-SRI antidepressants,
or placebo and found no significant differences across treatment
groups. This result is consistent with the finding from many comparisons
and meta-analyses that SRIs and other newer antidepressants have
usually proved to be effective in placebo-controlled trials and
seemed indistinguishable from tricyclic antidepressants in efficacy
based on measures other than suicidal behaviors (526, 786).
After publication of several case reports suggesting that
SRI antidepressants might be associated with increased risks of
aggressive or impulsive acts, including suicide (551–553,
787), a number of investigators retrospectively analyzed clinical
trial data to determine whether rates of suicide and suicidal behaviors
are increased with SRI treatment (533, 537, 548, 554, 555, 788).
These studies did not show evidence that suicide or suicidal behaviors
are increased by treatment with specific types of antidepressants.
Nonetheless, the safe and effective use of antidepressant treatment
for an increasingly wide range of psychiatric disorders should include
due regard to early adverse reactions to any antidepressant. These
reactions may include increased anxiety, restless agitation, disturbed sleep,
and mixed or psychotic bipolar episodesall of which represent
heightened subjective distress in already disturbed patients that
might increase the risk of impulsive or aggressive behaviors
in some vulnerable individuals. At the same time, these
medications are prescribed in order to treat disorders that may
have anxiety, agitation, and suicidality as part of the illness
course, making it difficult to distinguish the etiology of symptoms
that emerge in the course of treatment.
The evidence supporting an expected lowering of the risk for
suicidal behavior during antidepressant treatment is limited to
findings for patients with a diagnosis of major depression and is,
at best, only suggestive. At the same time, existing studies in
the literature are limited by the short-term nature of many trials,
the widely varying rates of suicide and suicidal acts across trials,
inclusion of some patients with probably unrepresentatively high
pretreatment suicide risk, and, in other studies, efforts to screen
out patients deemed to be at increased suicide risk. Nonetheless,
from a clinical perspective, the strong association between clinical
depression and suicide and the availability of reasonably effective
and very safe antidepressants support the use of an antidepressant
in an adequate dose and for an adequate duration as part of a comprehensive
program of care for potentially suicidal patients, including long-term
use in patients with recurrent forms of depressive or severe anxiety disorders.
On the basis of present knowledge about pharmacological interventions
and risk of suicidal behaviors, prophylactic treatment with lithium
salts of patients with recurrent major affective disorders is supported
by the strongest available evidence of major reductions in suicide
risk of any currently employed psychiatric treatment (528, 559–563,
565, 789). In contrast to antidepressants, and similar to clozapine
for schizophrenia, lithium typically is used in relatively structured
settings, including specialized programs for affective disorders,
lithium clinics, and prolonged maintenance therapy. This practice
pattern may itself contribute to the reduction of suicide risk as
a result of close, medically supervised monitoring of long-term
treatment. Several decades of clinical and research experience with
long-term maintenance treatment in recurrent major affective disorders
encouraged the development of controlled and naturalistic studies
with large numbers of patients given therapeutic dosages of lithium
for several years. Studies reporting on the relationship of lithium
treatment and suicide in patients with bipolar disorder and other
major affective disorders have consistently found much lower rates
of suicide and suicide attempts during lithium maintenance treatment
than without it (562, 563, 565, 789).
A recent meta-analysis of studies of suicide rates with and
without long-term lithium maintenance treatment (563) updated other
reviews of this topic (314, 315, 528, 558, 560, 562, 564, 565, 700, 790,
791) and found 34 reports for the period from 1970 through 2002
by computerized and other literature searching (76, 534, 559, 565–595).
These studies included 67 treatment arms or conditions (42 with
and 25 without lithium treatment). The total number of patients
was 16,221 (corrected for appearance of some subjects in both treatment
conditions), and treatment lasted an average of 3.36 years with
lithium therapy (N=15,323 subjects, for 51,485 person-years
of risk-exposure) and 5.88 years without lithium maintenance
treatment (N=2,168, for 12,748 person-years of exposure),
with an overall time at risk (weighted by the number of subjects
per study) of 3.76 years.
Meta-analysis yielded an overall estimated rate for all suicidal
acts (including suicide attempts) from all identified studies of
3.10% per year without lithium treatment, compared to 0.21% per
year with lithium treatment, a 14.8-fold (93.2%) reduction
that was highly statistically significant. Moreover, the finding
of lower rates of suicide and suicide attempts was consistently
seen in all 25 sets of observations except one, an early study with
a small sample size and relatively short time of exposure to lithium
treatment in which no suicidal acts were observed with or without
lithium treatment (566).
For suicides considered separately, pooled rates were 0.942% per
year without lithium treatment, compared to 0.174% per
year with lithium treatment. The corresponding figures for suicide
attempts considered separately were 4.65% per year and
0.312% per year, respectively. Thus, long-term lithium
treatment was associated with a 5.43-fold reduction in the risk
of suicide and a 14.9-fold reduction in the risk of suicide attempts
(563).
The apparent sparing of risk of suicide and suicide attempts
was very similar in patients with a diagnosis of bipolar disorder
and in those with other recurrent major affective disorders, although patients
with unipolar depressive disorder were evaluated separately in only
two relatively small studies involving a total of 121 patients that
found a reduction in risk of suicidal acts from 1.33% per
year to nil (563, 575). In addition, a comparison of subjects with
bipolar I disorder (N=263) and those with bipolar II disorder
(N=153) found a somewhat greater sparing of suicidal risk
in the patients with bipolar II disorder (from 1.70% to
0.305% per year, compared to a reduction from 2.73% to
0.898% per year in bipolar I disorder patients) (563).
Despite these striking reductions in risk, it is also important
to note that lithium maintenance treatment does not provide complete
protection against suicide. The overall rate of suicide during lithium
treatment was 0.174% per year, which was much lower than
the untreated risk of 0.942% per year but was still 10.5
times higher than the average international rate of 0.0166% per
year in the general population (700, 792). In contrast, the rate
of suicide attempts during lithium treatment was very close to the estimated
risk for the general population, and the total pooled rate of all
suicidal acts with lithium treatment, remarkably, was 33% lower
than the estimated general population risk. This striking finding
may be plausible in that much of the risk of suicidal behavior in
the general population represents untreated affective illness and
because suicide attempts are far more common than deaths by suicide.
In addition, these observations may suggest a relatively greater
effect of lithium treatment on suicide attempts than on suicide,
although the variability in relationship to general population risks
may also reflect variance in the samples available for the analysis
of rates of suicide and suicide attempts.
These studies have several notable limitations, including
a potential lack of control over random assignment and retention
of subjects in some treatment trials, inclusion of some patients
with probably unrepresentatively high pretreatment suicide risk,
and the presence in several trials of potential effects of treatment
discontinuation (565), which can contribute to an excess of early recurrence
of affective illness (315, 791, 793, 794), with sharply increased
suicide risk (315, 700). However, there was no evidence that the
time at risk influenced the annualized computed rate of suicide
or suicide attempts. Finding a reduction of suicide risk during
lithium treatment also might involve biased self-selection, since
patients who remain in any form of maintenance treatment for many
months are more likely to be treatment adherent and conceivably
also less likely to become suicidal. However, it is not feasible
to evaluate any long-term treatment in nonadherent patients. Moreover,
several of the reported studies involved either the same persons
observed with and without lithium treatment or random assignment
to treatment options, minimizing the effects of self-selection bias.
Results of these studies were consistent with the overall findings
of marked reductions of risk of suicidal behaviors during lithium
treatment (565).
If lithium is indeed effective in preventing suicide in broadly
defined recurrent major affective syndromes, as it appears to be,
it seems likely that this effect operates through reduction of risk
or severity of recurrences in depression or mixed dysphoric-agitated
states (69, 315, 700). An additional factor may be reduction of
impulsivity or of aggressive and hostile behavior with lithium facilitation of
the central serotonergic neurotransmission system (226, 366, 526,
795), although this hypothesis is inconsistent with evidence that
the antiserotonergic agent clozapine may reduce suicide risk in schizophrenia
(603, 796) and the lack of evidence for a beneficial effect of SRI
antidepressants on suicidal behavior (533, 563). An additional nonspecific
but potentially important benefit of lithium treatment may arise
from the supportive, long-term therapeutic relationships associated
with the typically structured and relatively closely medically monitored
maintenance treatment of patients with recurrent major mood disorders
who are being treated with lithium.
+
c) "Mood-stabilizing" anticonvulsant
agents
Evidence for a protective effect against suicide of putative "mood-stabilizing" agents
other than lithium is extremely limited. Reports from a long-term
collaborative German study that involved random assignment of patients
with bipolar disorder and schizoaffective disorder to 2 years of treatment
with either lithium or carbamazepine found no suicidal acts with
lithium but substantial remaining risk with carbamazepine
(592, 597). A recent study by Goodwin et al. (598) analyzed computerized
records of 20,878 patients with a diagnosis of bipolar disorder
(60,518 person-years of follow-up) in two major integrated health
plans who were treated with lithium, divalproex, or carbamazepine.
Approximately 27% of the person-years of exposure were
to lithium alone, 22% were to carbamazepine or divalproex
alone, and 47% had no exposure to any of the three medications. After
adjustment for potential confounds, including age, gender, health
plan, year of diagnosis, physical illness comorbidity, and use of
other psychotropic medications, the authors found that the risk
of suicide was 2.7 times higher during treatment with divalproex
or carbamazepine than during treatment with lithium. For suicide
attempts, the risk during divalproex or carbamazepine treatment was
1.9 times higher for attempts resulting in inpatient care and 1.7
times higher for attempts resulting in emergency department care,
compared to risk during lithium treatment. Thus, in patients treated for
bipolar disorder, risk for suicide attempts and for suicide was
significantly lower during lithium treatment than during treatment
with carbamazepine or divalproex.
No studies have addressed the risks of suicide attempts or
suicide during treatment with other proposed mood-stabilizing agents.
Given the widespread and growing use of divalproex, lamotrigine, oxcarbazepine,
topiramate, and other anticonvulsants, often instead of lithium,
it is extremely important to include measures of mortality risk
and suicidal behavior in long-term studies of the effectiveness
of these and other potential treatments for bipolar disorder. Such
information may eventually allow an approximate ranking of the effectiveness
of specific agents against the risk of suicidal behavior.
+
d) Antipsychotic agents
First-generation antipsychotic agents such as fluphenazine,
thiothixene, and haloperidol are highly effective in treating delusions
and hallucinations. However, it is not known whether or to what
extent they may have beneficial effects in limiting suicide risk
in psychotic patients. In the United States, the annual rate of
suicide associated with schizophrenia has not fallen appreciably
since the introduction of neuroleptics in the late 1950s (599–602),
suggesting that first-generation antipsychotics have a limited effect
on suicide risk.
Some first-generation antipsychotic agents may also have beneficial
actions in major affective disorders. Virtually all antipsychotic
agents are highly and rapidly effective in mania, and antipsychotic drugs
may also have beneficial effects in some patients with major depression,
with or without psychotic features (596). While these benefits may
reflect nonspecific improvements in agitation, insomnia, and other
distressing symptoms rather than specific antidepressant effects,
they may nevertheless reduce suicide risk in highly agitated patients,
especially those with psychotic forms of depression and mixed bipolar
states. On the other hand, haloperidol and perhaps some other first-generation
antipsychotics may worsen depression in patients with chronic psychotic
disorders as well as in those with major affective disorders, with
or without psychotic features (112, 797). Although not well studied,
the potentially distressing adverse effect of akathisia may actually
increase risk of suicidal and other impulsive or violent acts (604, 605). Thus, because of the other advantages of second-generation
antipsychotic agents in treating psychotic disorders (513) and perhaps
manic, mixed, and depressive phases of bipolar disorder (512), use
of first-generation antipsychotics in individuals with suicidal
behaviors should generally be reserved for those needing the enhanced
treatment adherence afforded by depot forms of medication.
Of all antipsychotics, clozapine is, by far, the best studied
for specific beneficial effects on suicidal behaviors. As the prototype
second-generation antipsychotic agent, clozapine differs from first-generation
antipsychotics in several respects, including a markedly lesser
propensity to induce adverse extrapyramidal neurological effects
(596). Clozapine has particular utility in the substantial subgroup
of patients with schizophrenia who poorly tolerate (798) or do not
respond adequately to first-generation agents (799) and
perhaps to other antipsychotics (596). In addition, clozapine
may have beneficial effects on cognition in psychotic patients (800, 801), can improve social and occupational functioning (513), may
limit the risk of abusing alcohol and other substances (802, 803),
and may also decrease impulsive and aggressive behaviors (804–806).
Evidence for the effect of clozapine on the risk of suicidal
behaviors comes from clinical trials involving patients with schizophrenia
and schizoaffective disorder as well as from registry studies, which
include all patients treated with clozapine regardless of diagnosis.
Data from the clozapine national registry, for example, indicated
a 75%–82% reduction in mortality, which
is primarily attributable to a decrease in suicide risk (608, 609).
An additional analysis of these registry data found a 67% reduction
in risk for suicide attempts (607). Reduced annual risk of suicide
was also found in clozapine-treated patients, compared to those
given other antipsychotic agents, in the Texas State Mental
Health System (609) as well as in the United Kingdom (610).
Sernyak et al. (611) used data on patients treated within
the VA system and compared all patients over a 4-year period
who initiated treatment with clozapine while hospitalized (N=1,415)
to a control group of patients with schizophrenia who were matched
to the clozapine-treated patients by using propensity
scoring (N=2,830). Over the follow-up period, the patients
who had been treated with clozapine at the index hospitalization
experienced a lower rate of mortality, due to lower rates of respiratory
disorders. However, the rate of suicide did not differ between the
groups, although there was a nonsignificant trend for fewer suicides
among those treated with clozapine. In addition, since patients
were not treated with clozapine throughout the follow-up period,
potential effects of clozapine on suicidality may have been less
pronounced (612, 613).
The effects of clozapine on suicidal ideation and suicide
attempts relative to patients' own baseline levels of suicidality
were first examined in a retrospective study of 88 patients with
chronic, neuroleptic-resistant DSM-III-R schizophrenia (N=55)
or schizoaffective disorder (N=33) and a mean duration
of illness of 14 years (607). Clozapine monotherapy with
a mean daily dose of 500 mg was initiated in the hospital, and suicidality
was assessed over a mean follow-up period of 3.5 years. At follow-up,
improvements in symptoms of depression and hopelessness were noted,
and the percentage of patients with no suicidal thoughts, plans,
or attempts had increased from 53% at baseline to 88% with
clozapine treatment. Compared to the 2-year period before initiation
of clozapine, there was also a decrease in the relative lethality
of suicide attempts and a 12.8-fold decrease in the annualized number
of suicide attempts.
Other studies have compared clozapine-treated patients to
patients treated with first-generation antipsychotics. Glazer and
Dickson (807), for example, found a 57% lower risk of suicide
attempts among schizophrenia patients treated with clozapine, compared
with those treated with haloperidol (606). In another study, Spivak
et al. (808) compared 30 patients with chronic, treatment-resistant schizophrenia
who had been maintained on clozapine for at least 1 year with an
equal number of patients who had been treated with first-generation
antipsychotics for similar lengths of time (808). They found that
clozapine treatment was associated with significant reductions in
ratings of impulsiveness and aggressiveness, along with fewer suicide
attempts.
In the International Suicide Prevention Trial (InterSePT),
a 2-year, multicenter randomized, controlled study with an open-label
design with masked ratings, the effects of clozapine (N=479)
were compared to those of olanzapine (N=477) in patients
with DSM-IV schizophrenia (N=609) or schizoaffective disorder
(N=371). Only 27% of the patients had an illness
that was refractory to prior treatment, but all were deemed to be
at unusually high risk for suicide, on the basis of having current suicidal
ideation or having made a suicide attempt during the previous 3
years. The prestudy rate of suicide attempts in this group was 21% per
year, or about four times that of broader samples of patients with
schizophrenia (603, 606, 607). Although only patients receiving
clozapine had blood drawn to monitor white blood cell counts, all
patients were seen weekly for 6 months, then biweekly for an additional
18 months to minimize bias from the clozapine-treated patients' more
frequent contact with health care staff. Primary endpoints, determined
by blinded raters and certified by a three-member independent, blinded,
expert Suicide Monitoring Board, included suicide attempts (including
those that led to death), hospitalizations to prevent suicide, and
a rating of "much worse suicidality" compared
to baseline. Patients randomly assigned to receive clozapine
showed a significantly longer time to a suicide event as defined
previously, with a significant reduction in the rate of all suicidal
events. In addition, fewer clozapine-treated patients
required hospitalization or other clinical interventions
intended to minimize suicidal behavior or were given an
antidepressant or a sedative. The significant advantage of clozapine
was evident in patients with schizoaffective disorder
as well as those with schizophrenia. In addition, patients with
more prestudy risk factors showed a relatively greater reduction
in the rate of suicidal behavior. Furthermore, the greater effectiveness
of clozapine was not due to superiority in treating positive or
negative symptoms as rated at endpoint. Very few of these high-risk
subjects died of suicide during the study (eight of 956 [0.837%] within
2 years), and the risk of suicide was nonsignificantly greater with
clozapine than olanzapine (1.044% and 0.629%,
respectively). The rate of suicide attempts was significantly less
during clozapine treatment than during olanzapine treatment (7.7% and
13.8%, respectively, without correction for exposure times).
However, the rate of suicide attempts during treatment with olanzapine
was approximately half that found among these high-risk patients
before the trial, suggesting that olanzapine treatment was associated
with some beneficial effects on the risk of suicidal behaviors.
Overall, studies of the risk of suicidal behaviors during
treatment with clozapine or other antipsychotic agents in chronically
psychotic patients have involved nearly 134,000 subjects treated with
clozapine and 123,000 given other antipsychotic agents (809). Although
the selection of high-risk subjects in the InterSePT study (603)
resulted in a great degree of heterogeneity in the frequencies of
suicidal acts across studies, together these results indicate substantial
superiority of clozapine over other antipsychotic agents in preventing
suicidal acts in patients with schizophrenia and schizoaffective
disorders. For other disorders, such as otherwise treatment-resistant
bipolar disorder, no information is available about the effects
of clozapine on risk of suicidal behaviors.
In clinical practice, the evident advantage of clozapine in
reducing the rate of suicide attempts and perhaps the rate of suicide
must be weighed against the risks of death from agranulocytosis, cardiomyopathy,
myocarditis, and rare atypical forms of a syndrome similar to neuroleptic
malignant syndrome (596). Other potential side effects of clozapine,
including seizures, weight gain, hyperlipidemia, and type
II diabetes, may also adversely affect longevity. Thus, in deciding
whether to institute or continue clozapine treatment in patients
with psychosis who are at risk for suicidal behaviors, the clinician
will need to weigh the advantages and disadvantages of clozapine
therapy for the individual patient.
For other second-generation antipsychotic agents, with the
exception of perhaps olanzapine as discussed earlier, there is little
direct evidence of an effect on suicidal behaviors. For the InterSePT
study, olanzapine was chosen as the comparator because of its use
in treating schizophrenia as well as limited evidence that it might
have a superior effect in reducing suicidal behaviors, compared
with haloperidol (810). There is also some evidence that the second-generation
antipsychotic agents, including olanzapine and risperidone, may
have mood-elevating or mood-stabilizing actions in addition to the
ubiquitous antimanic effects of virtually all antipsychotics (112).
These observations have led to the inference that second-generation
antipsychotics also may have greater utility than first-generation
agents in minimizing suicidal behaviors (811).
Compared to first-generation antipsychotics, the second-generation
agents are less likely to be associated with nonadherence that results
from extrapyramidal side effects and more likely to be associated
with stable or improved cognition and higher levels of social and
occupational functioning (801). Thus, there are general reasons
for preferring to use second-generation antipsychotic drugs rather
than first-generation antipsychotic drugs to reduce the risk for
suicide in patients with schizophrenia. At the same time, it remains
to be shown whether specific second-generation antipsychotic agents
differ from each other or from first-generation antipsychotics in
relative protective effects against suicidal behavior.
Some patients who die by suicide have symptoms of severe psychic
anxiety, panic, agitation, or severe insomnia close to
the time of the suicidal act (79, 217, 218). Such persons may also
abuse alcohol or other substances, perhaps in an attempt at "self-medication" for
otherwise intolerably distressing symptoms. Since antianxiety agents
can limit such symptoms, they also hold the possibility of reducing short-term
suicide risk. Several agents, including benzodiazepines, buspirone,
older sedatives, many antidepresssants, low doses of some
second-generation antipsychotics, and some mood-altering anticonvulsants,
may have calming effects in highly anxious and agitated patients
and so might be expected to limit suicide risk. However, research
addressing this plausible expectation is limited and inconclusive.
No clinical trial has demonstrated short- or long-term effects on
suicidal behavior of any type of antianxiety treatment.
However, a recent analysis of data obtained in controlled trials
of treatments for anxiety disorders found no significant differences
in rates of suicidal behavior between those treated with active
agents and those treated with placebo (118).
In treating potentially suicidal patients, benzodiazepines
are often avoided because of concerns about their potential for
inducing dependency (812), respiratory depression, or disinhibition,
as has been observed in some patients with borderline personality
disorder or mental retardation (614, 615, 813–815). Nevertheless,
the risk of disinhibition appears small (816). In addition, benzodiazepines can
limit psychic distress in depressed patients and improve sleep and
may thereby potentiate the clinical benefits of antidepressant therapy
(617–619). Whether such benefits are associated with reduced
suicide risk remains unproved, however. In contrast, removal of
a benzodiazepine during treatment may be associated with increased
risk of suicidal behavior (817). Thus, decisions about initiating
or continuing benzodiazepines in suicidal patients should consider
these risks and benefits as they relate to the individual patient.
In summary, it is clinically appropriate to provide treatments
aimed at reducing anxiety, psychic distress, agitation, and insomnia,
regardless of the primary diagnosis, as part of a comprehensive effort
to limit suicide risk, and antianxiety agents may have a useful
empirical role in such situations, when employed with due regard
to their risk of disinhibiting impulsive or aggressive behavior
(219).
Prominent suicidality is widely considered a clinical indication
for ECT (511, 512, 623). Much of the rationale for this practice
is indirect and based primarily on the established and superior
efficacy of ECT in treating severe depression that is often associated
with suicidal ideation and behaviors (623). ECT affords a more rapid
and robust clinical antidepressant response than psychopharmacological,
psychosocial, or other treatments, especially in severe, acute major
depression, with or without psychotic features (623).
Only four studies have directly assessed the short-term effects
of ECT on "suicidality" defined as apparent suicidal
thinking. Rich et al. (620) analyzed depression and suicide ratings
in a study designed primarily to measure treatment response with
increasing numbers of alternate-day, right unilateral ECT. Suicide
ratings, based on one item of the Hamilton Depression Rating Scale, improved
maximally within 1 week and improved significantly more rapidly
than measures of mood or lack of energy or interests. Similarly
rapid and robust declines in suicide ratings were found in a naturalistic
study of depressed patients with medication-resistant bipolar disorder
who were given ECT with pharmacotherapy (818). Prudic and Sackeim
(621) also found rapid and marked short-term reductions of suicidality
with ECT in 148 depressed patients, reductions that even exceeded those
in other Hamilton Depression Rating Scale items, especially, but
not only, among the 49% of individuals considered clinically
responsive to ECT. In data from a larger sample of 405 ECT-treated depressed
patients recently analyzed by Kellner et al. (622), 58% of
the patients were considered suicidal on the basis of suicidal ideation
or suicide plans or attempts. The patients were treated with bitemporal
ECT, and after a single treatment, suicidality was considered to
have resolved in one-third of these suicidal patients, in two-thirds
after three treatments, and in 95% by the end of a clinically
determined series of ECT treatments (averaging just over seven treatments
in the acute course).
These studies were limited by reliance on a single item from
one rating scale. In addition, examination of the effects of ECT
on suicidality was incidental to the primary aims of the studies,
and any changes in suicidality associated with ECT were possibly
incidental to the antidepressant effects of ECT. Moreover, no data
directly address the effects of ECT on suicidal behavior or suicide
fatalities. Nevertheless, and consistent with impressions arising
from clinical experience, available studies indicate that acute
treatment with ECT is associated with frequent and rapid reductions
in apparent suicidality, possibly even before major improvements
in other symptoms of depression.
As a means of evaluating possible long-term benefits of ECT
on suicidal risk, several studies have examined rates of suicide
in different treatment eras, before and after the introduction of
ECT (and other treatments), with follow-up periods as long as 10 years.
A recent meta-analysis, which calculated suicide rates from published
literature for patients with mood disorder who were followed naturalistically
for at least 6 months after an index hospitalization, indicated
a 41% decrease in suicide rates, from 1.33% to
0.770% per year, between the pre-ECT years and later years
when ECT and then antidepressants were in widespread use (819).
However, interpretation of this information for possible
effects of ECT is obscured by uncertain reliability in identifying
persons who died by suicide in different eras and by the effect
of multiple therapeutic developments across the decades included in
the analysis.
In an earlier study comparing clinically matched samples of
depressed patients from a Monroe County, New York, psychiatric case
register, Babigian and Guttmacher (820) assessed the effect of ECT
on mortality at 5-year follow-up between 1960 and 1975 for 1,587
patients treated with ECT and 1,587 who did not receive ECT. The
groups did not differ in risk for suicidal behavior or in overall
mortality, but their comparison may be confounded by the selection
of patients with severe symptoms for treatment with ECT. Additional
studies involving ECT were reviewed by Tanney (821), Prudic and
Sackeim (621), and Sharma (822). These studies were primarily nonrandomized, uncontrolled,
retrospective clinical observations from relatively small case series.
It is not surprising that they also failed to find evidence of enduring
effects on suicide rates after short-term ECT.
The available data thus suggest rapid short-term benefits
against suicidal thinking but do not provide evidence of a sustained
reduction of suicide risk following short-term ECT, despite its superior
effectiveness in severe depression (623). Similar to the situation
with antidepressant therapy, there is still very little information
arising from systematically applied and evaluated long-term treatment
with ECT comparable to the data available for maintenance treatment
with lithium and clozapine, and it is not reasonable to expect long-term
effects on suicide risk from time-limited treatment interventions
of any kind. In short, it remains to be tested whether long-term
use of maintenance ECT or short-term ECT followed by long-term antidepressant
or mood-stabilizing treatment may affect long-term risk of suicidal
behavior.
In addition to pharmacotherapies and ECT, psychotherapies
play a central role in the management of suicidal behavior in clinical
practice. Although few rigorous studies have directly examined whether
these interventions reduce suicide morbidity or mortality
per se, clinical consensus suggests that psychosocial interventions
and specific psychotherapeutic approaches are beneficial to the suicidal
patient. Furthermore, in recent years, studies of psychotherapies
have demonstrated their efficacy in treating disorders such as depression
and borderline personality disorder that are associated with increased
suicide risk (511, 515, 823–830). The apparent superiority
of combination treatment with psychotherapy and pharmacotherapy
in individuals with depression also suggests a need for further
study of such combination treatment in individuals with suicidal
behaviors (824, 826–830). Other psychosocial interventions
may also be of value in treating suicidal patients, particularly
given their utility in minimizing symptoms and risk of relapse in
patients with bipolar disorder and patients with schizophrenia (512, 513, 831).
+
1. Psychodynamic and psychoanalytic psychotherapies
In patients with suicidal behaviors, experience with psychodynamically
and psychoanalytically oriented psychotherapies is extensive and
lends support to the use of such approaches in clinical practice. Research
data on the effects of these therapies in suicidal patients are
more limited but supportive. For example, Bateman and Fonagy (624, 625) randomly assigned 44 patients with borderline personality disorder,
diagnosed according to standardized criteria, to either a standard
psychiatric care group or a partially hospitalized group who received
individual and group psychoanalytic psychotherapy for a maximum
of 18 months. At the end of the treatment period, as well as at
6-, 12-, and 18-month follow-ups, patients assigned to the psychoanalytically
oriented partial hospitalization group had significantly lower numbers
of self-mutilatory acts and were more likely to have refrained entirely
from self-mutilatory behavior in the preceding 6 months. In the
partial hospitalization group, similar highly significant reductions
were seen in the number of suicide attempts and in the number of
patients who had made a suicide attempt during the follow-up period.
During and after the treatment, parallel persistent improvements
were seen in other outcome measures, including fewer inpatient days,
reductions in depressive symptoms, and improved social and interpersonal
functioning in the psychoanalytically treated group. These data
demonstrate the efficacy of psychoanalytically oriented partial
hospital treatment in patients with borderline personality disorder.
Further, they show that such treatment can improve factors such
as depression and interpersonal functioning that modify suicide
risk and can simultaneously diminish a range of self-harming and
suicidal behaviors.
Stevenson and Meares (832) studied a group of 30 poorly functioning
outpatients with borderline personality disorder and found that
twice-weekly psychodynamic therapy resulted in significant reductions
in self-harm behaviors as well as in improved overall outcomes,
compared to the year preceding treatment. In addition, the 30 patients
treated with twice-weekly psychodynamic therapy also had better
outcomes and fewer self-harming behaviors relative to a group of
control subjects who received treatment as usual (833). Thus, although
limited by small samples and lack of random assignment to the control
condition, these studies also suggest a benefit of psychodynamic
approaches in reducing self-harming behaviors among individuals
with borderline personality disorder.
Clarkin et al. (834) developed a modified form of psychodynamic
treatment called Transference Focused Psychotherapy and used this
approach to treat 23 female patients with a diagnosis of DSM-IV borderline
personality disorder. Twice-weekly treatment with Transference Focused
Psychotherapy was associated with significant decreases on measures
of suicidality, self-injurious behavior, and medical and psychiatric
service utilization, relative to baseline levels. In addition, compared
to the year preceding treatment, there was a significant decrease
in the number of patients who made suicide attempts and in the medical
risk and severity of physical injury associated with self-harming
behaviors. Although again limited by a small sample as well as by
the lack of a control group, these findings coincide with clinical
impressions of benefit to suicidal patients treated with psychoanalytic
and psychodynamic approaches.
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2. Cognitive behavior therapy
Given the evidence for the effectiveness of cognitive behavior
therapy in treating depression and related symptoms such as hopelessness
(511, 825, 835–837), it might be expected to also be of
benefit in the treatment of suicidal behaviors. Again, however,
evidence from randomized trials is extremely limited.
In a randomized clinical trial involving 20 patients,
Salkovskis et al. (628) examined whether individuals at high risk
for repeated suicide attempts were more improved by treatment as
usual or by a cognitive behavior intervention that focused on teaching
problem-solving techniques. At the end of treatment and at follow-up
up to 1 year later, the group randomly assigned to the problem-solving
treatment showed significantly more improvement than control subjects
on ratings of depression, hopelessness, and suicidal ideation, and
over 6 months of follow-up, there was some evidence for a decrease
in suicide attempts. Although the sample was small, these findings
provide some evidence for the benefit of cognitive behavior interventions
in reducing suicidal ideation and behaviors in patients at high
risk for repeated suicide attempts.
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3. Dialectical behavior therapy
Dialectical behavior therapy, a psychosocial treatment for
borderline personality disorder that combines individual psychotherapy
with group practice of behavioral skills, has also been studied in
a randomized fashion with respect to its effects on self-injurious
behaviors. Linehan et al. (522, 838) randomly assigned 39 women
who had a history of self-injurious behavior and met the
criteria for borderline personality disorder to 1 year of dialectical
behavior therapy or treatment as usual. During the year of treatment,
as well as during the initial 6 months of follow-up, the patients
treated with dialectical behavior therapy had fewer incidents of
self-injurious behavior and those that did occur were less medically
severe. Functioning, as measured by the Global Assessment Scale,
and social adjustment were also better in the group treated with
dialectical behavior therapy. After 1 year, the group treated with
dialectical behavior therapy continued to require significantly
fewer psychiatric hospital days, but the benefits of the intervention
in reducing the number and severity of suicide attempts were no
longer apparent. In a subsequent study, Linehan et al. (523) compared
dialectical behavior therapy to treatment as usual in a group of
patients with borderline personality disorder and comorbid substance
dependence. Patients treated with dialectical behavior therapy had
more days of substance abstinence at follow-up intervals of up to
16 months. In terms of self-harming behaviors, dialectical behavior
therapy showed no benefits over treatment as usual, although patients
in both groups experienced reductions in self-injury. An additional
prospective study (839) evaluated 24 female patients with borderline
personality disorder who were treated with dialectical behavior therapy
in a 3-month inpatient treatment program and continued in outpatient
treatment with dialectical behavior therapy. Compared to ratings
at the time of hospital admission, a significant decrease in the
frequency of self-injury was noted 1 month after discharge
that coincided with improvements in ratings of depression, dissociation,
anxiety, and global stress.
Additional evidence for the effects of dialectical behavior
therapy in treating women with borderline personality
disorder comes from a randomized clinical trial conducted
by Verheul et al. (840). In this study, 58 women with borderline
personality disorder were assigned to 12 months of treatment with
either dialectical behavior therapy or treatment as usual. Particularly
in patients with a history of frequent self-mutilation,
dialectical behavior therapy was associated with greater reductions
in suicidal, self-mutilating, and self-damaging impulsive
behaviors, compared to usual treatment.
Taken together, the data from these trials suggest the possible
utility of dialectical behavior therapy in treating suicidal and
self-injurious behaviors in individuals with borderline personality
disorder. However, the sample sizes in these trials were small,
and it is not clear whether the patients were representative of
those seen in usual clinical practice. Larger samples are also needed
to determine whether some patients may be prone to paradoxical increases
in self-injurious behavior with dialectical behavior therapy (841).
Finally, since no data are available on the utility of dialectical behavior
therapy in the treatment of patients with diagnoses other than borderline
personality disorder, further study is needed before recommending
dialectical behavior therapy for routine use in the treatment of
individuals with suicidal behaviors.
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4. Other psychosocial interventions
As noted earlier, psychosocial interventions other than psychotherapies
have shown clear efficacy in the treatment of a number of psychiatric
disorders. To date, however, randomized clinical trials and longitudinal
studies of various psychosocial treatments have produced conflicting
results in individuals at risk for suicidal behaviors. Most interventions
have focused on the treatment of individuals identified at the time
of an index suicide attempt. For example, van der Sande et al. (842)
compared the clinical efficacy of an intensive psychosocial intervention
with treatment as usual in 274 randomly assigned individuals who
presented for medical treatment after attempting suicide. At 12-month
follow-up, the authors found no difference in the number of repeat
suicide attempts in patients receiving treatment as usual, compared
to those given intensive psychosocial treatment, which consisted
of brief admission to a crisis-intervention unit and problem-solving
aftercare. In contrast, in a randomized trial that compared brief
psychological treatment to treatment as usual in 119 individuals
seen in an emergency department for self-poisoning, Guthrie et al.
(843) found significant decreases in suicidal ideation and in additional
self-harm. Also, in a study of 120 suicide attempters, Welu (844) found
a statistically significant reduction in suicide attempts in those
who were randomly assigned to a 4-month follow-up outreach program,
compared with those randomly assigned to receive treatment as usual.
The three studies just described (842–844) were included
in an extensive review and meta-analysis of randomized clinical
trials of psychosocial interventions for the treatment of patients
with deliberate self-harm by Hawton et al. (627, 633). The interventions
considered in the meta-analysis were diverse and included problem-solving therapy,
dialectical behavior therapy, home-based family therapy, provision
of an emergency card to quickly gain access to care, and intensive
intervention plus outreach. While promising results were noted for
problem-solving therapy and provision of an emergency card, as well
as for dialectical behavior therapy, the sample sizes were too small
and the studies too underpowered to detect clinically significant
differences in effects on repetition of deliberate self-harm. Thus,
a number of psychosocial interventions have been targeted to individuals who
have made suicide attempts or engaged in other self-harming
behaviors; however, current evidence from randomized clinical trials
is too limited to support reliable conclusions about the efficacy
of these approaches in individuals with suicidal behaviors.
In addition to specifically targeting suicidal behaviors,
psychosocial interventions may indirectly decrease rates of suicide
attempts by enhancing the treatment of the patient's underlying
diagnosis. Rucci et al. (595) treated 175 patients with bipolar
I disorder for a 2-year period using primarily lithium pharmacotherapy
and either psychotherapy specific to bipolar disorder, which included
help in regularizing daily routines, or nonspecific intensive clinical
management involving regular visits with empathic clinicians. Before
patients entered the trial, the rate of suicide attempts was 1.05
per 100 person-months. During the acute treatment phase, patients
experienced a threefold reduction in the rate of suicide attempts,
with a 17.5-fold reduction during maintenance treatment, suggesting
that treatment in a maximally supportive environment could significantly reduce
suicidal behaviors in high-risk patients with bipolar disorder.
During the follow-up period, fewer suicide attempts occurred in
patients treated with psychotherapy specific to bipolar disorder;
however, because of the low numbers of suicide attempts during treatment,
it was not possible to determine whether the two psychosocial interventions were
statistically different in their effectiveness. Nonetheless, these
findings suggest that combinations of psychosocial interventions
and pharmacotherapy offer promise in diminishing risk of suicidal
behaviors in at-risk individuals.