Occurrence and Characteristics of Stroke Events in the Atrial Fibrillation Follow-up Investigation of Sinus Rhythm Management (AFFIRM) Study

Abstract

An estimated 2 260 000 individuals in the United States in 2000 have atrial fibrillation (AF). The prevalence will be such that by 2020 there will be 3 330 000 individuals in the United States with AF.¹ The median age of patients with AF is 75 years,² and stroke attributable to AF increases with advancing age, from 1.5% for those aged between 50 and 59 years to 23.5% for those between 80 and 89 years. Atrial fibrillation is an important risk factor for stroke. The annual risk of stroke in patients with nonvalvular AF not taking warfarin sodium is 3% to 5%, and AF is thought to be responsible for 15% of thromboembolic strokes. Additionally, AF increases the risk of death, after adjustment for other risk factors.³