Cognitive deficits and the course of major depression in a cohort of middle-aged and older community-dwelling adults

OBJECTIVES: To examine associations between cognitive deficits and persistent significant depressive symptoms at baseline and 2- and 4-year follow-ups in a sample of community-dwelling middle-aged and older adults. DESIGN: Prospective cohort study. SETTING: A U.S. national prospective cohort study of middle-aged and older adults, the Health and Retirement Study. PARTICIPANTS: A sample of 661 participants of the 1996 wave of the Health and Retirement Study who met criteria for 12-month Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised major depression (MD). MEASUREMENTS: MD was assessed using the World Health Organization Composite International Diagnostic Interview-Short Form. Persistent significant depressive symptoms were assessed using an eight-item version of the Center for Epidemiological Studies Depression scale. RESULTS: Cognitive deficits were associated with persistent significant depressive symptoms at follow-up. In a latent state-trait analysis, two stable and strongly correlated traits best explained variations in cognitive functioning and depressive symptoms across assessment points. CONCLUSION: Trait-like cognitive deficits commonly complicate the course of MD in community-dwelling middle-aged and older adults and may help to explain the persistent course of depressive symptoms in a large sub-group of adults with MD in this age range.