The association of age and depression among the elderly: an epidemiologic exploration

Advanced age among the elderly has been hypothesized to be a risk factor for depression, yet extant data do not uniformly support this hypothesis. The paucity of sufficiently large and representative samples of both the young-old and old-old and the failure to control for critical variables known to confound the association between advanced age and depression have prevented testing this hypothesis. The Duke EPESE (Establishment of a Population for Epidemiologic Studies of the Elderly) assessed 3,998 community-dwelling elders (65+) for depressive symptoms using a modified version of the CES-D and relevant control variables. Depressive symptoms were associated in bivariate analysis with increased age, being female, lower income, physical disability, cognitive impairment, and social support. In a multiple regression analysis, the association of age and depressive symptoms reversed when the above confounding variables were simultaneously controlled. The oldest old suffered fewer depressive symptoms when factors associated with both increased age and depressive symptoms were taken into account. Because many of these factors can be prevented (such as decreased income, physical disability, and social support), the uncontrolled association between age and depressive symptoms can potentially be modified.