Depression in Late Life: Review and Commentary

A 6-year follow-up of community dwelling older adults in The Netherlands illustrates the chronicity of late-life depression. Among those with clinically significant depressive symptoms, 23% remitted, 44% tracked an unfavorable but fluctuating course, and 33% tracked a severe chronic course. In the subthreshold group, 25% experienced a chronic course. Thirty-five percent of the major depressives and 52% of the dysthymics experienced a chronic course (13).

Major depression in older persons over longer follow-up periods exhibits a chronic remitting course in most clinical studies (86–91). In a 6-year follow-up of elderly depressives, 31% recovered and remained well, 28% suffered at least one relapse but recovered, 23% only partially recovered, and 17% remained depressed throughout the follow-up (86). In another study, among a group of elderly depressed patients (many of whom were medically ill) followed for 1 year, 35% had good outcome, 48% had either remittance and recurrence or remained continuously ill, 3% developed dementia, and 14% died (87). In a follow-up of younger subjects who experienced early-onset severe depression and survived into late life (follow-up for 25 years), only 12% remained continuously well in one study, with neurotic and endogenous depression exhibiting similar outcomes (92). These findings are similar to those in studies of persons in young adulthood and midlife (93, 94). Elderly depressed outpatients without significant comorbid medical illness or dementia and who are treated optimally may exhibit a much better outcome, with over 80% recovering and remaining well throughout follow-up (90). In contrast, elders with a lack of instrumental and social support and poor self-rated health experience a longer time to remission (95).

Medical comorbidity, functional impairment, and comorbid dementing disorders all adversely influence outcome of depression. Depression, in turn, adversely affects the outcome of the comorbid problems. Depression is a major cause of weight loss in late life (96). Depression is frequently associated with chronic medical illnesses such as cardiovascular disease, and it can complicate the course of these illnesses (97). In one study, older patients with depression following a myocardial infarction were much more likely to die in the first 4 months after the event (26% vs 7%) (98). Depression in late life was an independent risk factor for heart failure among elderly women but not among elderly men in another study (99, 100). In another study, depression was associated with a decrease in bone mineral density in controlled analyses in people aged 65 years or older (risk factors for osteoporosis) (101, 102). Finally, late-life depression has been found to be a risk for poor self-rated health over time (103).

Few mechanisms for these associations have been identified at present, yet some have been theorized and explored. Platelet activation is increased in elderly depressed patients, especially those with the serotonin-transporter-linked promotor region 5-HTTLPR polymorphism (this group had significantly higher platelet factor 4 and beta-thromboglobulin levels). This finding suggests how some depressed patients may be at greater biological risk for morbidity and mortality with ischemic heart disease (104). Poor appetite can lead to low body mass index associated with late-life depression and subsequent frailty and failure to thrive (41, 105, 106). In an 18-month prospective study of community-dwelling older adults (including both spousal caregivers of dementia patients and noncaregiving controls), those with chronic, mild depressive symptoms had poorer T-cell responses to two mitogens from baseline to follow-up. In addition, among those with depression, older age was associated with the poorest blastogenic response to mitogens at follow-up. The stress of caregiving may have augmented this response. Older patients with depression have higher levels of the cytokine interleukin 6, indicating increased inflammatory activity, which may be linked to increased bone resorption (or depressed patients may be more sedentary, leading to increased resorption rates), thus increasing the risk for hip fracture (107, 108).

Depression is clearly associated with functional impairment (2, 109, 110) and effects disability status over time (55, 111, 112). In one study, depression increased the risk for activities of daily living disability and mobility disability over 6 years by 67% and 73%, respectively (113). Even less severe symptoms of depression are associated with functional decline, such as “depression without sadness” (32). Disability is also a risk factor for depression (114, 115). A number of explanations have been proposed. Physical disability appears to lead to higher numbers of negative life events. In addition, physical disability can lead to restriction of valued social or leisure activities, isolation, and reduced quality of social support (116). If disability can be improved, then depression may be relieved. Yet another explanation is that depression as a state is disabling. For example, executive-type cognitive impairments caused by depression may explain why depressed persons are more disabled (55, 117). When depression accompanies stroke, functional outcome is compromised as well (118).

Functional decline is not inevitable following depression, however. A diagnosis of depression in older primary care patients in one study led to poorer self-reported role functioning but not to poorer self-reported physical functioning (119). Instrumental support provided to elders (such as helping with tasks) was generally protective against worsening performance on instrumental abilities of daily living among elderly patients with recurrent unipolar depression. Subjective and structural dimensions of social support protected the most severely depressed elderly patients against the loss of basic maintenance abilities (a clinical sample) (120).

Severe depression with cognitive impairment, even when the cognitive impairment remits, is a risk for Alzheimer's disease (AD) over 5 years (14). Early depressive symptoms among subjects with minimal cognitive impairment (MCI) may represent a preclinical sign and should be considered a risk factor for impending AD or vascular dementia (121). Depression further complicates the course of AD by increasing disability and physical aggression and leading to greater caregiver depression and burden (122–124). However, in a follow-up study, depressive symptoms among AD patients have higher rates of spontaneous resolution without requiring intensive drug treatment than among vascular dementia patients, in whom depressive symptoms are more persistent and refractory to drug treatment (121).

Nonsuicide mortality is a significant adverse outcome resulting from late-life depression. In a review of 61 reports from 1997 to 2001, 72% demonstrated a positive association between depression and mortality in elderly people (15). Another reviewer reported that, in 23 mortality studies of depression (subjects 65+ years of age), the pooled odds of dying if subjects were depressed were 1.75. A longer follow-up predicted smaller effect size. Both severity and duration of depressive symptoms predict mortality in the elderly population in these studies (125). Representative extant studies include summary data from the ECA study, in which the investigators found a fourfold increase in the odds of dying over a follow-up of 15 months if persons 55+ years of age experienced a mood disorder (111). Other cross-national studies of a positive association were found in Australia and Japan (126, 127). Among community-dwelling persons in The Netherlands, both major and minor depression increased the risk for cardiac mortality in subjects with and without baseline cardiac disease (128). The association between depression and mortality holds in many of these studies, despite the addition of potentially confounding variables. For example, in one study, high levels of depressive symptoms independently predicted mortality in a study where demographics, medical comorbidity, smoking, and body mass index were controlled (129). In studies from North Carolina and New York, however, investigators failed to find an association (130, 131). One reason for the lack of association in some studies may be the selection of control variables to be included, especially chronic disease and functional impairment. For example, in a study of the North Carolina Established Populations for Epidemiologic Study of the Elderly (EPESE) cohort, the unadjusted relative odds of mortality among depressed subjects at baseline was 1.98. These odds moved toward unity as other risk factors were controlled, such as chronic disease, and health habits, cognitive impairment, functional impairment, and social support were added to the model (132). Therefore, the specific variables controlled in mortality studies may determine the association between depression and mortality.

The effect of depression on mortality may vary by sex. In elderly Japanese American men but not women, depressive symptoms were a risk for mortality in the physically healthy (133). In another study, depressive symptoms were a significant risk factor for cardiovascular but not cancer mortality in older women (134, 135). In a controversial report, investigators found that subthreshold depression (CES-D scores of 12–16) was not associated with mortality in men but was negatively related to 3-year mortality in women (odds ratio = .6) (136). In other words, mild depressive symptoms were protective in this highly controlled analysis of community-based data.

Suicide frequency in the 65+ age group in the United States was 16.9/100,000 per year in 1998 (137, 138). The frequency for white men increased with age, reaching 62/100,000 in the 65+ age range. Frequency among nonwhite men was highest in young adulthood and was slightly higher in midlife among women. The association of depression and suicide has been well established in the literature across the life cycle (138–143). Elderly persons attempting suicide are also more likely to be widow(er)s, live alone, perceive their health status to be poor, experience poor sleep quality, lack a confidant, and experience stressful life events, such as financial discord and interpersonal discord (138, 143). The most common means of committing suicide is the use of voluntary drug ingestion. Whereas completed suicides increase with age, suicidal behaviors do not increase (144). There are approximately four attempts for each completed suicide in late life compared with 10 or more attempts per completed suicide earlier in life (145). Suicidal ideation is high among older adults, ranging from 5% to 10% of the population of older adults (138, 140).

Late-life depression leads to increased use of hospital and outpatient medical services (146–148). For example, having depressive symptoms was associated with a 19% increase in the number of outpatient encounters and a 30% increase in total outpatient charges in a Minnesota health maintenance organization. Taking antidepressant medications was associated with a 32% increase in total outpatient charges but was not significantly associated with number of outpatient encounters. Depressive symptoms and antidepressant therapy were not significantly associated with inpatient utilization or charges (149). Older persons are quite likely to use antidepressant medications, most of which are prescribed for depression (68). In a community sample in North Carolina, 14.3% of Caucasians and 5% of African Americans used antidepressants in 1996 (in controlled analyses, Caucasians were 3.8 times more likely to use antidepressants than African Americans).

Any discussion of the biological etiology of depression must begin with medical illness, for depression among the medically ill in late life is almost ubiquitous, as just documented. In addition to the association of depression with dementing disorders, cardiovascular disease, and hip fractures, among patients with Parkinson's disease, 20% meet criteria for major depression and 21% meet it for minor depression (150). Depression has been associated with pain in institutionalized elderly people (151) and is also common among homebound elders with urinary incontinence (152). Both alcohol dependence and major depression pose significant risk for the development of the other disorder at 1-year follow-up (153). In a series of recently reported studies, diastolic hypotension was associated with low positive affect, whereas systolic hypertension was associated with a positive affect. Use of antihypertensive medication was independently associated with lower positive affect in elderly people (154). Male veterans who were hospitalized during World War II for head injury were more likely to report major depression in subsequent years (155).

Great interest has arisen in recent years to search for genetic susceptibility to mood disorders across the life cycle (156). In a community sample of elderly twins, genetic influences accounted for 16% of the variance in total depression scores on the CES-D and 19% of psychosomatic and somatic complaints. In contrast, genetics contributed a minimal amount to the variance in reports of depressed mood and psychological well-being (157). Yet the likelihood of identifying a family history of mood disorder in a clinically depressed older adult is lower than for persons in midlife. In a clinical study, the risk for immediate relatives of patients with depression whose onset occurred after age 50 was 8.3% compared with 20.1% for relatives of patients whose onset occurred at a younger age (158).

Attention has been directed to specific genetic markers for late-life depression. Given the great interest in the ε4 allele of the apolipoprotein E gene, a number of studies have focused on this susceptibility gene for Alzheimer's disease. No association was found in a community sample between ε4 and depression (159). In another study, hyperintensities in deep white matter but not in the periventricular white matter were associated with depressive symptoms, especially in elders carrying the ε4 allele (160). Other investigators have concentrated on genes possibly associated with vascular lesions in the central nervous system. In one study, patients with late onset depression had an increased rate of the C677T mutation of the MTHFR (methylene tetrahydrofolate reductase) enzyme. This mutation may place older persons at risk for vascular depression (57). CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is a disease of the notch 3 gene. Depression is one of the initial symptoms in this condition, suggesting that genetic polymorphisms or mutations may predispose older adults to vascular depression. This genotype, however, is rare (161, 162).

Much attention has been directed to vascular risk for late-life depression, and this attention dates back at least 40 years, although the advent of magnetic resonance imaging boosted interest considerably (86, 63–166). Recent studies suggest that vascular lesions in selected regions of the brain may contribute to a unique variety of late-life depression—hence the interest in vascular depression as just discussed. The vascular depression impairments resemble impairments exhibited in frontal lobe syndromes. Magnetic resonance imaging of depressed patients has revealed structural abnormalities in areas related to the cortical-striatal-pallidal-thalamus-cortical pathway (167), including the frontal lobes (168), caudate (169), and putamen (170). These circuits are strongly implicated in the development of spontaneous performance strategies demanded by executive tasks. Recent interest has also focused on a smaller size of the orbital frontal cortex in late-life depression (171). In addition, left hippocampal volume has been found to be smaller in depressed elders who develop dementia over time (172). The frontal white matter (not gray matter) lesions in late-life depression are associated with increased myoinositol-creatinine and choline-creatinine ratios. These changes may reflect biological changes in nonneural (glial) tissue, which in turn affects synaptic activity (166).

Serotonin activity, specifically, 5 HT_2A receptor binding, decreases dramatically in a variety of brain regions through midlife, but there is less decrease from midlife to late life. These 5 HT_2A receptors in normal healthy subjects decreased markedly from young adulthood to midlife (70% from the levels at age 20 through the fifth decade), and then leveled off as age advanced. Receptor loss occurred across widely scattered regions of the brain (anterior cingulated, occipital cortex, and hippocampus) (18). The relationship of serotonin depletion can also be studied indirectly by the study of radioisotope-labeled or tritiated imipramine binding (TIB) sites. There is a significant decrease in the number of platelet-TIB sites in elderly depressed patients, compared with elderly controls and individuals suffering from Alzheimer's disease (173).

In aged monkeys (Macaca mulatta), significant age-related decreases in 5 HT_1A receptor binding were observed only in the frontal and temporal cortices. In the hippocampus, although 5 HT_1A receptor binding indicated nonsignificant age-related changes, the degree of displacement when binding to a receptor agonist was decreased in the aged monkeys. This finding suggests that age-related impairment of 5 HT_1A receptor response might be related to the reduced efficacy of antidepressant therapy in elderly patients with depression (174).

Endocrine changes have also been associated with late-life depression. Although the dexamethasone suppression test was long ago ruled out as a diagnostic test for depression, nonsuppression of cortisol is associated with late-life depression compared with age-matched controls (175). Depression is associated with hypersecretion of corticotropin-releasing factor (CRF), which is thought to mediate sleep and appetite disturbances, reduced libido, and psychomotor changes (176). Aging is associated with an increased responsiveness of adrenocorticotropic hormone (ACTH), cortisol, and dehydroepiandrosterone sulfate (DHEA-S) to CRF (177). Low levels of DHEA have been associated with higher rates of depression and a greater number of depressive symptoms in community-dwelling older women (178). Total testosterone levels were lower in elderly men with dysthymic disorder than in men with major depressive disorder and men without depressive symptoms in another study (179). However, the efficacy of testosterone in treating depression has not been established (180). Depression has also been associated with postprandial systolic hypotension (181). Hormone replacement in women has been associated with improvements in mood (182).

Behavioral, psychodynamic, and cognitive aberrations have all been suggested as causes of late-life depression. Three examples will illustrate these proposed etiologies. The behavior of learned helplessness, originally used to described the increasingly passive behavior of dogs produced by inescapable shock, has been expanded to explain depressive symptoms across the life cycle, suggesting that the cause of depression is the expectation that initiating action in a continually stressful environment is futile (6, 183, 184). The association of depression with severe or frequent adverse life events could be interpreted in part as a behavioral response to continued adverse stressors. Depression in old age has been associated with emotional abuse and neglect during childhood, as well as relational stress and problem behavior of significant others during late adulthood (especially high when many events reported during adulthood and late adulthood) (185). In a meta-analysis, the number of total negative life events and daily hassles was associated with depression in elderly people (186). Severe events show the largest relative risk, but ongoing difficulties account for the most episodes. The association of severe events with onset tends to be stronger in first than in recurrent episodes. Mild events can trigger a recurrence but not a first episode, suggesting that once the development of the behavior of “depression” follows a stressor, the triggers for subsequent episodes of depression need not be severe there-after (187).

According to one psychodynamic theory, the search for restitution secondary to the inevitable losses in late life is a major developmental task for aging individuals and a depression-like syndrome may appear, a “depletion syndrome,” when this task is not accomplished successfully. If one lives long enough, the inevitable object loss, body change, and disease lead to a state of both internal and external depletion (6, 188). A more recent yet controversial theory complements the depletion theory, suggesting that successful aging is associated with “selective optimization with compensation” (189). This model is based on a recognition by the elder of the realities of aging, especially the losses. Such recognition leads to selection of realistic activities, optimization of those activities, and compensation for lost activities, which in turn leads to a reduced and transformed life.

Perhaps the most dominant psychological model of depression is the model of cognitive distortions (190). In a case-control study, patients with major depression perceived greater negative impact of life events than patients with dysthymic disorder and healthy controls (191). The interpretation of life events is the key to understanding depression under this theory. Cognitions may be distorted such that the elder has unrealistic expectations, overgeneralizes certain adverse events, overreacts to events, and personalizes events. Perceived negative interpersonal events are associated with depression in elders, particularly in those who demonstrate a high need for approval and reassurance in the context of interpersonal relationships. In contrast, negative achievement events are associated with depression in those who placed a heavy emphasis on personal success and control. This conceptualization is consistent with the diathesis-stress model, namely that negative experience best predicts depression when a specific type of event affects a personal vulnerability (192, 193).

The association between late-life depression and impaired social support has been established for many years. In a community study in Hong Kong (194), impaired social support and depression were associated (including network size, network composition, social contact frequency, satisfaction of social support, and instrumental-emotional support). Impaired social support is associated with poorer outcome of depression in older men but not older women (195). In female caregivers of demented elderly people, the prevalence rate of depressive disorders reaches 45–47%, and these women are twice as likely to use psychotropic drugs (196, 197). Loneliness may be a key factor in depression among caregivers (198). Some have attempted to couple the theory of social disengagement with aging (much debated in the literature) with depression, suggesting that some symptoms of depression, such as lack of social interest and greater self-involvement, mirror attributes of older adults according to Disengagement Theory (199, 200). Other factors being equal, it is probable that elders who are less socially engaged are more depressed. For example, elders who stopped driving had a greater risk of worsening depressive symptoms (201).

Religious practice is associated with less depression in elderly Europeans (EURODEP), both on the individual and the national level. This is especially true when religious practice is embedded within a traditional value orientation (202). Some investigators have proposed that “religious coping” (subjects perceiving that religion is the most important factor in coping) is associated with improved emotional and physical health (203, 204). They found that religious coping was associated with a decrease in certain types of depressive symptoms, including loss of interest, feelings of worthlessness, withdrawal from social interactions, loss of hope, and other cognitive symptoms of depression. Religious coping was not associated with a reduction in somatic symptoms.

Antidepressant medications have become the foundation for the treatment of moderate to severe depression in older adults. Virtually all antidepressant medications are equally effective for treating serious major depression across the life cycle (19, 215, 216). Studies that compare tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) usually find equal efficacy, yet there are fewer side effects with SSRIs (217). Therefore, SSRIs are the treatment of choice (203, 206). The antidepressants even appear to be efficacious in subjects with subcortical hyperintensities (vascular depression) (218, 219). Although subjects with depression and smaller frontotemporal volumes on magnetic resonance imaging were more treatment resistant in one study (220), a number of studies document the efficacy of antidepressant therapy for treating depression in dementia (221–223).

Antidepressants appear less efficacious in treating less severe depression (224). A large study in a primary care setting found that paroxetine showed moderate benefits for depressive symptoms and mental health functioning in elderly patients with dysthymia and more severely impaired elderly patients with minor depression (compared with problem-solving therapy) (225). The overall evidence suggests that antidepressants and counseling have relatively small benefit in these less severe conditions (226). The use of St. John's wort (Hypericum perforatum) has been recommended for less severe depression and, given that it is available over the counter, it is used by mildly depressed older adults (and perhaps some who are more severely depressed). A recent study did not find that St. John's wort was as effective as sertraline in moderately severe major depression (mostly persons in midlife) (227). Nevertheless, this study has been criticized for not focusing on the mildly depressed.

Most of the SSRIs have been demonstrated to be efficacious in elderly people, including the drugs fluoxetine (228), sertraline (229), paroxetine (217, 230), citalopram (231), and fluvoxamine (232). (Escitalipram, recently entering the antidepressant market, has not been shown to be specifically efficacious in the elderly population.) Other new-generation antidepressants that have been shown to be efficacious include venlafaxine (233), mirtazapine (234, 235), nefazodone (in a general study of depression), and buproprion (236, 237). Nefazodone (238) has not been shown to be specifically efficacious in elderly people, because to date there has been no study of the drug in the elderly population.

In a recent consensus of practicing geriatric psychiatrists, the SSRIs along with psychotherapy are the treatments of choice for late-life depression, along with venlafaxine XR. Buproprion and mirtazapine are alternates (as was electroconvulsive therapy, or ECT, in severe depression). Medication (SSRI plus an antipsychotic, with risperidone and olanzapine being the antipsychotics most commonly recommended) and (or) ECT are the preferred treatments of unipolar psychotic major depression. Medications plus psychotherapy are recommended for dysthymic disorder. Education plus watchful waiting are recommended for minor depression that lasts for less than 2 weeks (anti-depressant medication plus psychotherapy are recommended for minor depression if symptoms persist). The preferred anti-depressant for treating both major and minor depression is citalopram (20–30 mg) followed by sertraline (50–100 mg) and paroxetine (20–30 mg), with fluoxetine (20 mg) as an alternate. Nortriptyline (40–100 mg) is the preferred tricyclic agent, with desipramine (50–100 mg) as the alternate. The consensus recommendation is to continue an antidepressant 3–6 weeks before a change in medications is made. If little or no response is observed, the consensus is to switch to venlafaxine (75–200 mg). For a first episode of depression with recovery following antidepressant therapy, 1 year of continual therapy is recommended. For two episodes, 2+ years of continual therapy and for three or more episodes, 3+ years of continual therapy are recommended (239), as shown in Table 3.

Many factors may alter the efficacy or the side effects of the antidepressant drugs in late life. For example, estrogen therapy and DHEA have been demonstrated to augment sertraline treatment (240, 241). A number of the cytochrome P450 enzymes that metabolize most medications are inhibited by antidepressants, such as CYP3A, CYP2D6, DYP2C, CYP1A2, and CYP2E1. The CYP3A enzymes metabolize 60% of the medications used today. Fluoxetine is a moderate inhibitor of CYP3A4. Approximately 8–10% of adults lack the CYP2dD6 enzyme, and paroxetine is a potent inhibitor of this enzyme (which may explain, among some patients treated with paroxetine, the lack of efficacy of analgesics such as codeine that are metabolized by this enzyme). Citalopram and venlafaxine are the “cleanest” of the medications in terms of inhibition of the cytochrome P450 enzymes (242, 243).

Elderly inpatients on SSRIs or venlafaxine are at definite risk for developing hyponatremia (39% in one study) and should have sodium levels checked before and after commencement of antidepressant medications (244). This hyponatremia is due to the syndrome of inappropriate secretion of antidiuretic hormone. Other serious side effects reported with the SSRIs include the risk of falls (no less risk than with the tricyclics in one study) (245), the serotonin syndrome (lethargy, restlessness, hypertonicity, rhabdomyolysis, renal failure, and possible death) (246), and gastrointestinal bleeding (247). Less serious side effects include weight loss, sexual dysfunction, anticholinergic effects (most pronounced with paroxetine), agitation, and difficulty sleeping.

Subjects with psychotic depression respond poorly to antidepressants but well to ECT (248). Many studies have documented the effectiveness of ECT in older adults (249–251). Some investigators report the response as good in elderly as in young people (252), whereas others suggest that the response is less optimal in the oldest old (253). In one study using bilateral ECT versus pharmacotherapy, the 65+ age group had a better response to ECT than younger age groups (254). Memory problems remain the major adverse effect from ECT that affects quality of life. Memory problems are usually transient and clear within weeks following treatment. A relatively new procedure that could replace ECT in some situations is repetitive transcranial magnetic stimulation (rTMS) (255). TMS does not require anesthesia and seizure induction is avoided. Though not studied specifically in elderly people, in one outcome study, patients treated with rTMS compared with ECT responded equally well and their clinical gains lasted at least as long as those with ECT (256). In another study, executive function improved in both middle-aged and elderly depressed subjects with rTMS compared with sham treatments (257).

Investigators with the Alameda County Study explored the association of exercise and depression, controlling for functional status. Among subjects who were not depressed at baseline, those who reported a low activity level were at significantly greater risk for depression at follow-up (258). On the basis of controlled trials, an aerobic exercise training program may be considered an alternative to antidepressants for treatment of depression in older persons (259). However, the advantages of exercise are not limited to aerobic activities. Unsupervised weight lifting has been found to decrease depressive symptoms up to 20 weeks after induction (260). Light therapy may also be beneficial, especially if the depression follows a seasonal pattern. Thirty minutes of bright light a day improved depression among institutionalized elders in one controlled study (261).

Psychotherapy has received much attention and study as a treatment modality for depressed older adults over the past 20 years. This attention results from the development of “manualized” therapies, such as cognitive behavioral therapy (CBT) and interpersonal therapy (IPT). These therapies can be taught clearly and easily to Masters-level clinicians and can be monitored for accuracy in following the procedures of the therapy. Most of these therapies are short term (12–20 sessions) and therefore much more attractive to third-party payers. In addition, the educational (as opposed to a reflective) posture of the therapist employing manualized therapies is attractive to elders. In one study comparing range of referrals, outcomes, attendance rates, and length of time in therapy between older and younger adults participating in cognitive therapy, there was no significant differences in therapy outcome apart from home adjustment measures where older adults showed greater improvement. Younger adults showed significantly higher rates of nonattendance and had higher dropout rates (262).

Nevertheless, psychotherapy remains an infrequently prescribed therapy for depressed older adults. In a study of general internists, only 27% said they would refer a depressed older adult for psychotherapy (263). In a sample of primary care elderly patients in Quebec, the acceptability of a therapy was dependent on the severity of symptoms. CBT and cognitive bibliotherapy were rated more acceptable than antidepressants when the symptoms were less severe. Antidepressants were more acceptable than either CBT or bibliotherapy when the patient's symptoms were severe (264).

CBT and IPT have been the most frequently studied of the manualized therapies (20, 262–266). Exact mechanisms that render CBT and IPT effective, however, remain unclear (267). CBT focuses on thoughts that may perpetuate depression. The therapeutic goal of the therapist is to teach the patient to change these thought patterns or adapt to them. By changing thoughts, people change dysfunctional attitudes as well, and these attitudes are hypothesized to precipitate and perpetuate depressive thoughts (192). Studies increasingly suggest that the more central mechanism for changing thought patterns is the development of metacognition, that is, “stepping back” and responding to negative thoughts as transitory events rather than as inherent aspects of the self (268). In one study comparing CBT and brief psychodynamic therapy to a wait-list control group, all of the treatment modalities led to a comparable and clinically significant reduction of depression (265). Twelve months after the treatment, 58% of the sample population was depression free, and at 24 months, 70% was depression free. In another study, older depressed patients were assigned to CBT alone, medication alone, or a combination of medication and CBT (269). Although all groups showed improvement, the combined group showed the greatest improvement.

IPT is a manualized treatment that focuses on four components hypothesized to lead to or maintain depression: grief (e.g., death of a loved one); interpersonal disputes (e.g., conflict with adult children); role transitions (e.g., retirement); and interpersonal deficits (e.g., lack of assertiveness skills). The treatment has been adapted specifically for older adults (270, 271). In combination with nortriptyline, IPT has been shown to be an effective treatment for elderly depressed subjects (90, 272, 273). In one study, investigators achieved an excellent initial response (74%) with only 15% recurrence at the end of 1 year (90). Subjects who respond do not tend to relapse over fairly extensive periods (272).

More reflective therapies include psychodynamic therapy, life review therapy, and reminiscence therapy. Cases of successful psychodynamic therapy have been presented in the literature among older adults (274), and in one study psychodynamic therapy was as effective as CBT (275). Given its very nature, however, psychodynamic psychotherapy is most difficult to investigate empirically. In life review therapy, subjects are encouraged to acknowledge past conflicts and consider their meaning. In reminiscence therapy, the focus is more on positive memories in group settings. Both structured and unstructured reminiscence therapy lead to improvement compared with controls, and the structured group did even better (276). In contrast, another study found no improvement over wait-list controls (277). Bibliotherapy emphasizes a skills acquisition approach through select readings from books. For example, subjects may read Feeling Good (278), a self-help book that emphasizes employing cognitive skills to overcome depression. In a series of controlled randomized studies for mild to moderate depression in older adults, bibliotherapy was shown to be efficacious (279–282). Bibliotherapy has advantages for older adults. Elders can read and process the material at their own pace. Fears of stigmatization can be avoided and, for elders with impaired activities of daily living, this intervention does not require as many visits to a therapist (267).

Group therapy is used frequently with older adults, though it is less often studied compared with individual therapy (283). Self-management therapy and education groups were equally effective and superior to wait-list controls in one study (284). CBT and psychodynamic group therapy were more effective than placebo but less effective than tricyclics in other studies (285, 286). In a recent study, investigators found that antidepressant medication plus clinical management, either alone or with addition of group-administered dialectical behavior therapy (skills training and scheduled coaching sessions), found that the medication-dialectical behavior therapy groups had a higher continued remission rate than medications alone (267, 287).

In geriatric patients with recurrent major depression, maintenance treatment with nortriptyline or IPT is superior to placebo in preventing or delaying recurrence. Combined treatment using both appears to be the optimal clinical strategy in preserving recovery (272). Combined treatment with nortriptyline and IPT is also more likely to maintain social adjustment (performance-impaired or not, interpersonal behavior-hypersensitivity, friction-quarreling, satisfaction-loneliness) than treatment with either alone (288).

The PROSPECT (Prevention of Suicide in Primary Care Elderly-Collaborative Trial) is testing whether a trained clinician (a “health specialist”) can work in close collaboration with a primary care physician to implement a comprehensive depressive management program including pharmaco-therapy and IPT. The goal is to reduce suicidal ideation (289). Older patients with suicidal ideation in the midst of a recurrent episode of major depression respond as well as nonsuicidal patients, yet those with ideation have higher relapse rates during continuation treatment and were more likely to receive augmentation pharmacotherapy (290).