Symptoms of depression as a prospective risk factor for stroke.

OBJECTIVE: The objective of this study was to assess baseline levels of depression as a risk factor for stroke among white and black men and women.
METHODS: A population-based cohort of 6095 stroke-free white and black men and women aged 25 to 74 years in the NHANES I Epidemiologic Followup Study were followed for an average of 16 years to a maximum of 22 years. The association between stroke and baseline self-reported depressive symptomatology was analyzed using Cox proportional hazards models adjusting for baseline age, race, sex, education, smoking status, body mass index, alcohol use, nonrecreational physical activity, serum cholesterol level, history of diabetes, history of heart disease, and systolic blood pressure. Hospital records and death certificates were used to identify stroke cases; a total of 483 cases were identified.
RESULTS: In age-adjusted models for all persons, white men, white women, and black persons of both sexes, depression was predictive of stroke. In risk-adjusted models for all persons (relative risk (RR) = 1.73, 95% confidence interval (CI) = 1.30-2.31) and for white men (RR = 1.68, 95% CI = 1.02-2.75), depression remained predictive of stroke. For white women, depression (RR = 1.52, 95% CI = 0.97-2.38) reached borderline significance (p = .07). For black persons, depression (RR = 2.60, 95% CI = 1.40-4.80) demonstrated a higher risk of stroke. A series of supplemental analyses also supported the association between depression and stroke.
CONCLUSIONS: Depression is predictive of stroke across all strata. This nationally representative study gives evidence of a prospective association between depression and stroke.