Prevalence and Correlates of Depression in an Aging Cohort: The Alameda County Study

Data on symptoms of major depressive episodes were examined for the 1994 cohort (n = 2,417) of the Alameda County Study (mean age = 65). In addition to age, we examined gender, education, marital status, social isolation and social support, perceived physical and mental health, chronic medical conditions, functional impairment, life events, financial strain, and neighborhood quality. The point prevalence of symptoms of major depressive episodes was 6.6 percent for men and 10.1 percent for women, with a trend for prevalence to increase with age. When the effects of the other psychosocial risk factors were controlled, there were no significant age effects. Multivariate analyses demonstrated that apparent initial age effects were due almost entirely to chronic health problems and functional impairment. The implications are clear: Healthy, normal-functioning older adults are at no greater risk of depression than younger adults. Apparent age-related effects on depression are attributable to physical health problems and related disability.