Rates and Determinants of 5-Year Outcomes After Atrial Fibrillation-Related Stroke: A Population Study.

Abstract

Demographic trends in atrial fibrillation (AF) incidence may yield a substantial rise in the societal burden of AF-related stroke (AF-stroke). Accurate population-wide outcome data are essential to inform health service planning to improve AF-stroke prevention, and provision of rehabilitation, nursing home, and community supports for AF-stroke survivors. We investigated rates and determinants of 5-year fatality, stroke recurrence, functional outcomes, and prescribing of secondary prevention medications in AF-stroke in the North Dublin Population Stroke Study. Ascertainment included hot and cold pursuit using multiple overlapping sources. Survival analysis was performed using lifetables and Kaplan-Meier survival curves, and Cox proportional hazard modeling was performed to identify predictors of death and recurrent stroke. Five hundred sixty-eight patients with new stroke were identified, including 177 (31.2%) AF-stroke. At 5 years, 39.2% (confidence interval, 31.5-46.8) of ischemic AF-stroke patients were alive. Congestive heart failure, hypertension, age <65, 65-74 years, and ≥75 years, diabetes mellitus, prior stroke, transient ischemic attack or thromboembolism, vascular disease and female sex (CHA2DS2-VASc) score (hazard ratio [HR], 1.34; P<0.001), CHADS2 score (HR 1.42, P=0.004), National Institute of Health Stroke Scale (HR, 1.09; P<0.0001), and subtherapeutic international normalized ratio (<2.0) at stroke onset (HR, 3.29; P=0.003) were independently associated with 5-year fatality, whereas warfarin (HR, 0.40; P=0.001) and statin use after index stroke (HR, 0.52; P=0.005) were associated with improved survival. The 5-year recurrence rate after ischemic AF-stroke was 21.5% (confidence interval, 14.5-31.3). Trends toward greater risk of recurrence were observed for persistent AF (HR, 3.09; P=0.07) and CHA2DS2-VASc score (HR, 1.34; P=0.07). Nursing home care was needed for 25.9% of patients. AF-stroke is associated with considerable long-term morbidity, fatality, stroke recurrence, and nursing home requirement. Adequately resourced national AF strategies to improve AF detection and prevention are needed.