Risk factors and outcomes for ischemic stroke.

Stroke continues to have a great impact on public health in the United States. Stroke is frequent, recurring, and is more often disabling than fatal. The annual incidence of new strokes in the United States is nearly one half million, with over 3 million stroke survivors alive today. Identifying risk factors for initial ischemic stroke, as well as characterizing the determinants of outcome (stroke recurrence and mortality) after ischemic stroke, is the basis for stroke prevention strategies. Modifiable and nonmodifiable risk factors for ischemic stroke have been identified and include age; gender; race/ethnicity; heredity; hypertension; cardiac disease, particularly atrial fibrillation; diabetes mellitus; hypercholesterolemia; cigarette smoking; and alcohol abuse. New risk factors, such as hypercoagulable states and patient foramen ovale, are currently being investigated. Follow-up studies have quantified case-fatality rates, early recurrence risk, and long-term mortality and recurrence risks. Despite advances in stroke prevention strategies and treatments, stroke recurrence is still the major threat to any stroke survivor. A major goal set by the Public Health Service in its National Health Promotion and Disease Prevention Objectives for the year 2000 is "to reduce stroke deaths to no more than 20 per 100,000." Part of this can be achieved if the risk of stroke recurrence is reduced. However, the frequency and determinants of stroke recurrence are poorly understood. Data from epidemiologic studies can help identify risk factors and outcomes after ischemic stroke, as well as the selection of high-risk individuals for focused risk-factor modification. Current information on these topics is discussed.