Prevalence of diagnosed atrial fibrillation in adults - National implications for rhythm management and stroke prevention: the AnTicoagulation and Risk Factors in Atrial Fibrillation (ATRIA) study

Context Atrial fibrillation is the most common arrhythmia in elderly person s and a potent risk factor for stroke. However, recent prevalence and proje cted future numbers of persons with atrial fibrillation are not well descri bed. Objective To estimate prevalence of atrial fibrillation and US national pro jections of the numbers of persons with atrial fibrillation through the yea r 2050, Design, Setting, and Patients Cross-sectional study of adults aged 20 years or older who were enrolled in a large health maintenance organization in C alifornia and who had atrial fibrillation diagnosed between July 1, 1996, a nd December 31, 1997, Main Outcome Measures Prevalence of atrial fibrillation in the study popula tion of 1.89 million; projected number of persons in the United States with atrial fibrillation between 1995-2050. Results A total of 17974 adults with diagnosed atrial fibrillation were ide ntified during the study period; 45% were aged 75 years or older. The preva lence of atrial fibrillation was 0.95% (95% confidence interval, 0.94%-0.96 %). Atrial fibrillation was more common in men than in women (1.1% vs 0.8%; P<.001). Prevalence increased from 0.1% among adults younger than 55 years to 9.0% in persons aged 80 years or older. Among persons aged 50 years or older, prevalence of atrial fibrillation was higher in whites than in black s (2.2% vs 1.5%; P<.001). We estimate approximately 2.3 million US adults c urrently have atrial fibrillation. We project that this will increase to mo re than 5.6 million (lower bound, 5.0; upper bound, 6.3) by the year 2050, with more than 50% of affected individuals aged 80 years or older. Conclusions Our study confirms that atrial fibrillation is common among old er adults and provides a contemporary basis for estimates of prevalence in the United States. The number of patients with atrial fibrillation is likel y to increase 2.5-fold during the next 50 years, reflecting the growing pro portion of elderly individuals. Coordinated efforts are needed to face the increasing challenge of optimal stroke prevention and rhythm management in patients with atrial fibrillation.