Changes in Depressive Symptoms and Subsequent Risk of Stroke in the Cardiovascular Health Study

BACKGROUND AND PURPOSE: Depression is associated with stroke, but the effects of changes in depressive symptoms on stroke risk are not well understood. This study examined whether depressive symptom changes across 2 successive annual assessments were associated with incident stroke the following year. METHODS: We used visit data from 4319 participants of the Cardiovascular Health Study who were stroke free at baseline to examine whether changes in depressive symptoms classified across 2 consecutive annual assessments predicted incident first stroke during the subsequent year. Depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression scale (high versus low at ≥10). Survival models were inverse probability weighted to adjust for demographics, health behaviors, medical conditions, past depressive symptoms, censoring, and survival. RESULTS: During follow-up, 334 strokes occurred. Relative to stable low scores of depressive symptoms, improved depression symptoms were associated with almost no excess risk of stroke (adjusted hazards ratio, 1.02; 95% confidence interval, 0.66-1.58). New-onset symptoms were nonsignificantly associated with elevated stroke risk (adjusted hazards ratio, 1.44; 95% confidence interval, 0.97-2.14), whereas persistently high depressive symptoms were associated with elevated adjusted hazard of all-cause stroke (adjusted hazards ratio, 1.65; 95% confidence interval, 1.06-2.56). No evidence for effect modification by race, age, or sex was found. CONCLUSIONS: Persistently high symptoms of depression predicted elevated hazard of stroke. Participants with improved depressive symptoms had no elevation in stroke risk. Such findings suggest that strategies to reduce depressive symptoms may ameliorate stroke risk.