Depressive symptom deterioration in a large primary care-based elderly cohort.

OBJECTIVE: The purpose of this study is to examine the incidence and clinical predictors of symptom deterioration in depressed elderly patients who have responded to treatment in primary care. METHOD: A cohort study of 901 older adults from 18 primary care clinics in five states who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for major depression and/or dysthymia at baseline interview, had participated in a trial of collaborative care for depression compared to usual care, and had improved to the point of no longer meeting criteria for major depression at 12 months were observed for one year (18 and 24 months) after enrolling in the original study. RESULTS: A total of 40% of patients met criteria for significant depressive symptom deterioration over the 12- to 24-month observational period. Among usual-care patients, higher initial severity of depression and a higher number of residual DSM-IV depressive symptoms at 12 months were significant predictors of symptom deterioration. No variables predicted symptom deterioration in intervention patients. CONCLUSIONS: There is a high rate of symptom deterioration among elderly patients in primary care who are treated for depression. Efforts to improve long-term outcomes of older patients with major depression and/or dysthymia should focus on providing more intensive treatment and follow up for patients with residual depressive symptoms.