Diagnosed Posttraumatic Stress Disorder and Other Trauma-Associated Stress Disorders and Risk for Suicide Mortality

This study used health care data from nine U.S. health care systems to allow for a large and diverse population and the inclusion of multiple trauma and stress diagnoses. The analyses were controlled for sex, age, and any co-occurring psychiatric condition (i.e., other known risks for suicide) (25, 26).

Individuals who died by suicide were more likely to be male (77.2% of case group members vs. 47.3% of control group members) and middle aged (49.2% were ages 40–64 vs. 38.7% of control group members) or older (22.2% were ages ≥65 vs. 13.6% of control group members) (Table 1). Youths (ages 0–17) in the case group were least likely to die by suicide (4.1% of case group members). Individuals in both groups were most likely to be enrolled in commercial insurance (68.5% of case group members and 80.1% of control group members), followed by Medicare (24.7% and 13.1%, respectively). Of the full case sample, 14.3% (N=475) had a trauma-associated stress condition diagnosis within the year before the index date, compared with 3.4% (N=11,217) of control group individuals.

The presence of any trauma-associated stress diagnosis in the year before the index date was associated with higher risk for suicide (Table 2). When the analyses were adjusted for sex and age, individuals with any diagnosed trauma-associated stress condition were more likely to die by suicide (adjusted OR [AOR]=5.82, 95% CI=5.26–6.45). Of the subgroups, the most elevated risk for death by suicide was seen among individuals diagnosed as having PTSD (AOR=10.10, 95% CI=8.31–12.27), followed by those having a diagnosis of other stress reactions (AOR=5.38, 95% CI=4.78–6.06) or acute reaction to stress (AOR=4.49, 95% CI=3.58–5.62). When the analyses were adjusted for age, sex, and comorbid psychiatric condition, suicide risk remained elevated for all trauma-associated stress conditions, and the pattern of elevated risk remained the same as that in previous models across diagnoses.

On average, individuals who died by suicide had more psychotherapy appointments than did control group individuals (Table 3). Individuals who died by suicide were also more likely to have attended a health care appointment (including psychotherapy or other medical care) at which any of the trauma-associated stress conditions were recorded (indicating that a provider had identified or discussed the condition) than those in the control group. Individuals who died by suicide were also more likely than control group individuals to have attended a health care appointment in the month before the index date, although the proportion of individuals who were seen in the month before the index date was low across conditions and groups. The shortest average length of time between a health care appointment and death by suicide was seen among those with PTSD (mean±SD=82.3±94.2 days), and the longest time interval was seen among those with a diagnosis of other stress reaction (mean=105.4±100.1 days) (Table 3).

This study brings an important focus to trauma-associated stress diagnoses as clear risk factors for suicide mortality among U.S. populations. About 14% of individuals in our sample who died by suicide had a diagnosed trauma-associated stress condition, and all trauma conditions were linked to increased risk for suicide. Although the highest risk for suicide mortality was associated with PTSD, significantly elevated risks were seen for other, often less emphasized diagnoses. This article uniquely contributes to the field by demonstrating that PTSD is a risk factor for suicide mortality among health system–affiliated individuals. Findings build on those of previous studies that examined PTSD as a risk factor for suicide mortality among other populations (5, 8). Past studies (15, 16, 19, 28) of veterans and Danish civilians with PTSD found risk levels similar to that seen in our population, lending support to the assertion that PTSD is a risk factor for suicide mortality worldwide.

This study further contributes to the field by exploring the risk for suicide across a spectrum of trauma-associated mental health conditions (20). Our findings suggested that all trauma-associated stress conditions are associated with increased risk for suicide mortality, calling attention to the need to consider all types of traumatic stress symptomatology as risk factors for suicide mortality and supporting efforts to treat reactions to trauma as a spectrum of functional impairment and symptomatology (20, 29–31). Acute reaction to stress and other stress reactions are often considered subclinical in comparison with PTSD; however, our findings suggested the importance of taking these categories seriously, because individuals with these diagnoses are also at high risk for suicide mortality (20, 32, 33).

Variation in risk for suicide mortality was seen across trauma conditions. PTSD was associated with the highest risk for suicide mortality, followed by other stress reactions and acute reactions to stress, which demonstrated similar levels of risk. These results differed from those of a Danish epidemiological sample (20), in which similar risk for suicide was found across all trauma-associated stress disorders. This difference in comparative risk may have been due to lack of consistent screening and identification of acute reactions to stress and other stress reactions in the current study’s participating health systems. System staff (consisting of many types of providers) may have been less aware of or knowledgeable about stress disorders other than PTSD and may therefore have been less likely to screen for or diagnose these conditions (34, 35). In contrast, behavioral health providers were responsible for diagnosing conditions among individuals in the Danish sample (20), which may be indicative of a more comprehensive description of the type and prevalence of trauma conditions. Alternatively, the possibility exists that individuals with other stress reactions and those with acute reactions to stress experienced less severe symptomatology or were more likely to be referred to and engage in behavioral health treatments, lowering their relative risk for suicide mortality compared with those with PTSD. These findings support the need for additional training of medical providers to improve their ability to recognize and diagnose traumatic stress conditions and to refer individuals with these conditions to appropriate treatment as a key suicide prevention strategy.

Consistent with our previous work (8), this study found that, compared with control group individuals, those who died by suicide were more likely to have had a health care appointment in which a trauma diagnosis was recorded, indicating that these individuals were likely experiencing more severe symptoms that motivated them to seek care (i.e., psychotherapy). The shortest average duration from health care visit to death by suicide was approximately 82 days (among patients with PTSD). Individuals who died by suicide were also more likely to have attended a health care appointment in the month before the index date. These findings highlight the important work being done in health care systems to identify and effectively provide intervention for those at risk for suicide and the need for further improvement and support to ensure patients in need are promptly identified and engaged in high-quality, trauma-informed care.

This study provided information on the relative population-level risk for suicide mortality, as well as the specific number of individuals at risk, in our health system sample (8). Although individuals with PTSD had the highest risk for suicide mortality, they represented a relatively small number compared with individuals with other trauma-associated stress conditions. Alternatively, although individuals with a diagnosis of other stress reaction demonstrated slightly lower risk for suicide mortality, this subgroup was nearly three times larger than the subgroup with PTSD. Given the serious risk for suicide among individuals with any trauma-associated stress diagnosis, population-level screening and referral measures should be implemented in conjunction with effective universal screening protocols for suicide (e.g., Zero Suicide, the Parkland suicide screening program) across health systems (36, 37). Moreover, individuals with trauma-associated stress conditions should be referred to and provided with trauma-informed behavioral health treatment and other support services that lower their individual risk (21, 31, 32, 36). Future research is needed to study the absolute risk for suicide for individuals with traumatic stress conditions.

This study also explored how the presence of a comorbid psychiatric condition affects suicide risk among individuals with trauma-associated stress disorders. Our results indicated that risk for suicide among those with trauma conditions persisted even after analyses were controlled for comorbid psychiatric condition, although, as expected, the magnitude of risk was lower. These findings suggested that trauma-associated stress conditions should be considered independent risk factors for suicide and that the risk increases when a comorbid psychiatric condition is present. However, analyses that are controlled for comorbid mental health conditions among individuals who have experienced trauma should be interpreted carefully, given the impact of trauma across symptoms and domains of functioning (38). Some scholars argue that co-occurring disorders are, for many people, a consequence of their trauma exposure and PTSD (15, 20). In fact, some empirical evidence (15, 20) has shown that the development of new-onset diagnoses of depression, anxiety, and substance use stems from exposure to trauma and the experience of traumatic stress, and that the development of this additional comorbid condition increases the effects of PTSD on suicidality. Although our study design limited our ability to determine diagnostic onset, future longitudinal analysis should be conducted to further understand how comorbid psychiatric conditions may develop after trauma, how this development may affect suicide risk, and where concomitant intervention points exist within health care settings serving trauma survivors.

One limitation of this study was the use of ICD-9-CM codes to capture trauma-associated stress conditions. The use of the adjustment disorder diagnosis has been poorly conceptualized and lacks diagnostic specificity (23, 39, 40). These disorders are often used by providers to diagnose trauma-associated stress conditions that do not meet criteria for either PTSD or acute reactions to stress (23, 24, 39–41). Moreover, concerns also exist for the overuse of adjustment diagnoses, whereby these disorders may be used to indicate normal stress reactions (23). To increase diagnostic clarity, a new ICD-10 diagnosis, known as “reaction to severe stress,” was created to distinguish traumatic stress from adjustment disorders, and several proposals have been made to further clarify and differentiate stress-associated disorders for ICD-11 (23). Given the current study’s use of ICD-9-CM codes, heterogeneity likely was present in our other stress reaction category. Moreover, because of the lack of diagnostic clarity, future health system screening and intervention protocols may consider alternative strategies (traumatic event and symptom checklists, clinician assessments) for monitoring impairment and risk after trauma exposure, and future longitudinal research should explore how risk for suicide may vary across the spectrum of trauma symptoms.

Several characteristics of our sample may have limited the generalizability of our results. First, all individuals in our sample had some health care coverage (although the sample represented a diverse spectrum of commercial, self-pay, and public insurance options). Given the disparities in access to and use of health care among individuals with trauma experiences, our findings may represent less severe risk than that seen among uninsured populations (42). Second, although the overall sample size was large (a strength of our study), a total of 535 cases of a diagnosed trauma condition were found. Although a smaller sample size was expected, because of overall prevalence rates, this number should be considered an underestimate. Moreover, the trauma conditions in this study were not mutually exclusive—60 people in the case group had multiple diagnoses (resulting in 475 individuals with trauma disorders). This variability was likely caused by variation in provider awareness of and training in diagnosing certain trauma-associated conditions. Because providers were responsible for recording diagnostic codes at each encounter, it is possible that some providers did not identify or record trauma conditions, whereas other providers, such as psychotherapists who regularly treat trauma conditions, routinely did so. Third, control group criteria excluded individuals who died in the year before the index date (e.g., incidents of accidental overdose), which may have affected the differences in risk seen between the case and control groups. Finally, because race and ethnicity data were not collected by MHRN staff before 2009, such data were absent from our analyses. We have attempted to comment on the geographically diverse nature of our sample by sharing other studies performed by our network (25, 26) and hope to explore the associations between trauma, suicide risk, and race and ethnicity in future studies.

Over 14% of individuals who died by suicide were given any diagnosis of a trauma-associated stress condition in the year before death, and all diagnostic trauma categories were associated with high risk for suicide mortality. This study fills an important gap by investigating the association between PTSD and risk for suicide in a U.S. health system population. This work further contributes to the field by assessing several traumatic stress diagnoses that represent a spectrum of trauma-associated symptomatology and impairment and by providing suggestions to improve health system suicide prevention strategies.