MORTALITY, SYMPTOMS, AND FUNCTIONAL IMPAIRMENT IN LATE-LIFE DEPRESSION

OBJECTIVE: To determine whether depressive symptoms measured at baseli ne are associated with mortality and to describe the course of depress ive symptoms and their relation to physical decline in patients over a 6-year period. DESIGN: Prospective cohort study conducted from 1990 t hrough 1996. SETTING: Urban academic primary care group practice. PATI ENTS:A cohort of 3,767 patients aged 60 years and older screened for d epressive symptoms during routine office visits using the Centers for Epidemiologic Studies Depression Scale (CES-D) participated in the mor tality study. A subsample of 300 patients with CES-D scores 16 or abov e and a subsample of 100 patients with CES-D scores less than 16 parti cipated in the study of the course of depressive symptoms and physical decline. MEASUREMENTS AND MAIN RESULTS: Mortality by December 1995 wa s measured for all screened patients; reinterviewed patients completed the CES-D and the Sickness Impact Profile (SIP). The mean follow-up p eriod was 45 months (+/- SD 12.2 months): 561 (14.9%) of the patients died by December 1995. In proportional hazards models, age, gender, ra ce, history of smoking, serum albumin value, and an ideal body weight in the lowest 10% were significant correlates of time to death, but th e baseline CES-D was not. Patients with depressive symptoms had signif icantly worse physical and psychosocial functioning scores on the SIP than did patients without depressive symptoms. Using the generalized e stimating equation method, the strongest predictor of the current CES- D score was the patient's prior CES-D score. However, worsening physic al functioning score on the SIP was also independently correlated with worse CES-D scores (p less than or equal to .001). CONCLUSIONS: Sympt oms of depression were not associated with mortality in this cohort of older adults. However, patients with depressive symptoms reported gre ater functional impairment than did those without depressive symptoms. Moreover, decline in physical functioning was independently correlate d with a concurrent increase in depressive symptoms.