Background: Blacks have been underrepresented (<2% of 71,683) in recent atrial fibrillation (AF) trials of novel anticoagulants vs. warfarin. Blacks with AF have also been underrepresented in stroke cohort studies from which the stroke risk prediction rules are derived.
Objective: We examined whether there exist racial differences in presentation, treatment, and outcome among patients with AF-related ischemic stroke (IS).
Methods: Consecutive IS were identified from 2006-2010 at 3 U.S. sites. All events were evaluated by CT or MRI, and assigned a discharge modified Rankin score (mRS). AF was confirmed by ECG. Baseline medications and clinical characteristics were abstracted from the medical record. Race was determined by self-report.
Findings: We identified 1,030 AF-related IS; 96% (n=985) had race reported as White (n=764, 74%) or Black (n=221, 21%). Compared to Whites, Blacks were younger, had a higher burden of risk factors, had higher prevalence of paroxysmal or new onset AF, and more often presented outside the t-PA window. Among patients with known AF, 40% Whites and 39% Blacks were taking warfarin on admission. INR on admission was not different by race (mean 1.4, SD =0.7; p=0.64). These strokes resulted in severe neurological deficit (mRS >3) in a majority of Blacks and Whites (70% vs. 64%; p=0.09).
Conclusion: Blacks with AF who suffer IS are younger, have a higher burden of risk factors, and more often present with paroxysmal or new onset AF. IS in the setting of AF was associated with significant mortality and morbidity in both Blacks and Whites.