Impairments in health functioning and sleep quality in older adults with a history of depression.

OBJECTIVES: To determine whether older adults with a history of depression show impairments in health functioning and sleep quality at a gradient between older adults with no history of depression and those with current major depression and to examine whether poor sleep quality contributes to declines in health functioning in addition to the contribution of depressive symptoms.
DESIGN: Cross-sectional.
SETTING: Three urban communities: Denver, Colorado, and Los Angeles and San Diego, California. PARTICIPANTS: Two hundred community-dwelling adults aged 60 and older who were never mentally ill, 143 with a history of major or minor depressive disorder in remission, and 67 with a current depressive disorder. MEASUREMENTS: Diagnosis, Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; health functioning (Medical Outcomes Study 36-item Short-Form Health Survey); depressive symptom severity (Beck Depression Inventory); and sleep quality (Pittsburgh Sleep Quality Index).
RESULTS: Older adults with a history of depression showed impairments in sleep quality and had lower levels of health functioning than controls; these impairments were at a gradient with declines in those with current depression. Poor sleep quality was independently associated with declines in health perception in older adults with and without depression.
CONCLUSION: These findings have important health implications for older people who have a lifetime history of depression, given evidence that poor health functioning is a risk factor for depression recurrence as well as mortality. Moreover, in view of the association between sleep quality and health status, testing of interventions that target sleep quality might identify strategies to improve health functioning in older adults.