Burden of Atrial Fibrillation–Associated Ischemic Stroke in the United States

Objectives: This study aimed to investigate whether the excess morbidity and mortality of atrial fibrillation (AF)–related stroke persists in the contemporary era. Background: Acute ischemic stroke (AIS) in patients with AF is associated with worse outcomes than in patients without AF. Stroke prevention strategies in patients with AF have improved over the last decade and AIS-related mortality overall has also declined. Methods: Patients ≥18 years of age who were admitted with AIS between 2003 and 2014 were identified in the National Inpatient Sample. The study compared crude and propensity score–matched in-hospital morbidity and mortality, cost, length of stay, and discharge dispositions between patients with and without AF. Results: A total of 930,010 patients were admitted with AIS, and 18.2% of these patients had AF. The prevalence of AF in these patients increased from 16.4% in 2003 to 20.4% in 2014, with the greatest increase observed in white and older patients. Propensity score matching attained 2 pairs of 125,203 patients with AIS with and without AF. In these matched cohorts, the mortality rate was higher in patients with AF (9.9% vs. 6.1%; p < 0.001). Ischemic stroke in patients with AF was also associated with higher incidences of acute kidney injury, bleeding and infectious complications, and severe disability. Hospital length of stay was significantly longer, and cost of care was 20% higher in patients with AF. Conclusions: The prevalence of AF in AIS patients continued to rise, particularly in white and older patients. Despite the improvement in AIS-related morality overall, the differential negative impact of AF on the morbidity, mortality, and cost of AIS was steady over the study's 12-year period.