Prior depression history and deterioration of physical health in community-dwelling older adults--a prospective cohort study.

OBJECTIVE: Depression worsens outcomes of physical illness. However, it is unknown whether this negative effect persists after depressive symptoms remit in older adults. This study examined whether prior depression history predicts deterioration of physical health in community-dwelling older adults.
DESIGN: Prospective cohort study.
SETTING: Three urban communities in the United States. PARTICIPANTS: Three hundred fifty-one adults aged 60 years or older-145 with a history of major or nonmajor depression in full remission and 206 concurrent age- and gender-matched comparison subjects with no history of mental illness. MEASUREMENTS: Participants were assessed at baseline, 6 weeks, 1 year, and 2 years for physical health functioning (the Physical Component Summary of the 36-Item Short-Form Health Survey) and chronic medical burden (the Chronic Disease Score). Given the repeated nature of measurements, linear mixed model regression was performed.
RESULTS: Both physical functioning and chronic medical burden deteriorated more rapidly over time in the group with prior depression history compared with comparison subjects, and these changes were independent of the measures of mental health functioning, depressive symptoms, and sleep quality. Similar results were observed when those who developed depressive episodes during follow-up were excluded.
CONCLUSION: A prior history of clinical depression is associated with a faster deterioration of physical health in community-dwelling older adults, which is not explained by current levels of depressive symptoms and mental health functioning or by recurrence of depressive episodes. Careful screening for a history of depression may identify those older adults at greatest risk for physical declines and chronic medical burden.