We found a point prevalence of 26.7% for major depression among older adults receiving assessments for care management from a community-based aging services provider at the point of entry to care and thus prior to linkage with services. Thirty-one percent of subjects scored 10 or more on the Patient Health Questionnaire-9, a cut-point typically used to designate clinically significant depressive symptoms. Summary figures for any depressive disorder are comparable to some prior studies14,15
but higher than others using comparable measures,12,13
likely reflecting methodological differences, the heterogeneity of ASPN provider agencies and the populations they serve, and the point in the enrollment/assessment process that the research assessment was conducted. Our evaluations were conducted at intake to social services care management, and therefore included only older adults facing significant stressors, both acute and chronic, in their lives.
Also of note, three-quarters of those with a current MDE reported one or more previous episodes of illness, and an additional 19.8% who did not meet MDE criteria at intake reported a past history as well. In total, therefore, the lifetime prevalence of MDE in the sample was 46.8%, far higher than the estimated lifetime prevalence of 10% for mood disorder in community-dwelling older adults.29
Over one-third of the sample was prescribed a medication for depression, anxiety, or stress, including over 60% of those with MDE. At the same time, however, over half of those taking a psychotropic medication had no current MDE, suggesting either that medications were being prescribed nonspecifically for distress or that prior treatment had been effective for some in resolving their mood disorders. Unfortunately, unavailability of information on the class and dose of medication prescribed, the timing of its use relative to depressive episodes, and the subjects’ adherence to prescribed therapy precludes further examination of these issues.
There are several possible explanations for the pattern of depressive illness observed here. First, older adults who utilize Eldersource services may comprise a group particularly prone to affective illness because of their heavy burden of social stressors, physical illness, and functional impairments. Second, they may represent a population of elders who frame their distress as social rather than psychological or medical in nature, and who, therefore, present preferentially for care to ASPN agencies rather than to mental health or primary care providers. Third, late life depression may make older adults more prone to social morbidities (secondary, for example, to withdrawal that is symptomatic of the illness) and thus, the need for ASPN intervention. Fourth, while our overall participation rate was comparable with other community based studies,30
only a portion of care management clients was referred to the study by their CMs. It is possible, therefore, that elderly clients with depression were over-represented in our sample. However, they were comparable in gender, race, income, and marital status to the nonenrolled Eldersource clients, and younger age of study subjects is unlikely to account for higher rates of depression, as other studies have not consistently found an association between age and rates of major depression in the older adult population. Further study of the natural history of affective illness in ASPN agency clients, including its phenomenology, is needed.
With regard to the correlates of depression in ASPN clients, our findings generally support previous studies conducted with community and clinical samples. In multivariate analyses, objective (but not perceived) social support remained in the model. For each point lower on the LSNS, a subject had 4.3% increased chance of being depressed. A difference in 10 points represented over 40% increased risk, suggesting clinical significance. Because aging service providers are equipped to address elders’ social network deficits, for example, by utilizing activity-based programs and mobilizing peer and family support, they are well-qualified to assist in management of late life depression.
Both the frequency of life events and the subjective “impact” of a significant negative event were associated with MDE. CMs who provide in-home services to their clients are also well-positioned to identify stressors, place them in context, and bring resources to bear that mitigate their impact.
Difficulty in performing IADLs was also positively associated with depression.31
Assessment of functional capacity is routine practice for ASPN CMs to assist their clients in obtaining the most appropriate and needed services, such as transportation assistance, meals, financial management, and home health aides.
Consistent with previous research, self-rated health,32
medical illness burden,33
were associated with the presence of a current MDE as well. Because of attitudinal and economic barriers, older adults are often reluctant to seek mental health services, preferring instead to obtain help for depression from their primary care providers.6
Yet rates of detection and adequate treatment of depression in primary care settings are low.5
Although collaborative care models that bring mental health resources, nurse care managers, and expertise to the primary care setting show promise of improving outcomes of depression treatment in later life,35–37
the social service setting may have an important role to play.10
Finally, the strength of one’s faith or religious affiliation was inversely associated with depression. Use of religion as a means to cope with stress has been associated with lower rates of incident depression in older men, and a lower rate of religious involvement was significantly associated with suicide in later life.38,39
Although aging services agencies are typically secular organizations, their ability to support independent community functioning may have the indirect benefit of facilitating the elder’s engagement in a faith community, thereby, reducing depression-related morbidity and mortality.
Limitations of the Study
Sampling issues are important to consider in interpreting these results. It is possible that the subjects had higher rates of psychological distress than those who chose not to participate. However, the two groups were similar demographically, and the most common reasons for nonparticipation were that the client had no further interest in Eldersource services or elected not to enroll as a research subject. Depressive symptoms of withdrawal, anergia, and hopelessness are likely to correlate with the decision not to participate. It is equally plausible, therefore, that affective disorder is underrepresented in the study sample.
Eldersource does not utilize a priori criteria with which to determine eligibility for care management services. Neither was randomization to care management visits feasible. Furthermore, sampling was restricted to those who spoke English well enough to participate in the interview, and the great majority of participants were white, non-Hispanic. Our findings, therefore, may not generalize to other agencies that have different operating procedures and serve a more diverse clientele.
The diagnosis of current MDE required that the subject have 2 weeks or more of persistent symptoms sufficient to meet Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition
criteria for the disorder. However, because the assessments were conducted at one time point early in the subjects’ interactions with the agency, we do not know the extent to which their depressions responded to the CMs’ ministrations, and if they did, over what time period. Would quick resolution of an elderly client’s depression indicate that the disorder was of less clinical significance? Or would it suggest that the social intervention was a robust treatment for the client’s depression? Longitudinal studies of depressed ASPN clients receiving CM “care as usual” are needed to explore such important questions further.15
Finally, we used p <0.05 as an indicator of statistical significance rather than adjust statistically for multiple comparisons. Such adjustments can inflate the risk of Type II errors and have a number of other limitations,40
and at this early stage of research in aging service settings, we believe this less conservative approach is appropriate. Certainly, however, there is a risk of spurious findings and the results should be cautiously interpreted in that light.