title: Rates of Atrial Fibrillation in Black Versus White Patients With Pacemakers.
abstract: BACKGROUND
  Black US residents experience higher rates of ischemic stroke than white residents but have lower rates of clinically apparent atrial fibrillation (AF), a strong risk factor for stroke. It is unclear whether black persons truly have less AF or simply more undiagnosed AF.
  
  
  RESULTS
  We obtained administrative claims data from state health agencies regarding all emergency department visits and hospitalizations in California, Florida, and New York. We identified a cohort of patients with pacemakers, the regular interrogation of which reduces the likelihood of undiagnosed AF. We compared rates of documented AF or atrial flutter at follow-up visits using Kaplan-Meier survival statistics and Cox proportional hazards models adjusted for demographic characteristics and vascular risk factors. We identified 10 393 black and 91 380 white patients without documented AF or atrial flutter before or at the index visit for pacemaker implantation. During 3.7 (±1.8) years of follow-up, black patients had a significantly lower rate of AF (21.4%; 95% CI 19.8-23.2) than white patients (25.5%; 95% CI 24.9-26.0). After adjustment for demographic characteristics and comorbidities, black patients had a lower hazard of AF (hazard ratio 0.91; 95% CI 0.86-0.96), a higher hazard of atrial flutter (hazard ratio 1.29; 95% CI 1.11-1.49), and a lower hazard of the composite of AF or atrial flutter (hazard ratio 0.94; 95% CI 0.88-99).
  
  
  CONCLUSIONS
  In a population-based sample of patients with pacemakers, black patients had a lower rate of AF compared with white patients. These findings indicate that the persistent racial disparities in rates of ischemic stroke are likely to be related to factors other than undiagnosed AF.
authors.affiliation: Department of Neurology and Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY hok9010@med.cornell.edu.
authors.forename: Hooman
authors.initials: H
authors.lastname: Kamel
authors.affiliation: Department of Neurology, University of Cincinnati, OH.
authors.forename: Dawn O
authors.initials: DO
authors.lastname: Kleindorfer
authors.affiliation: Division of Cardiology, University of Iowa Carver College of Medicine, Iowa City, IA.
authors.forename: Prashant D
authors.initials: PD
authors.lastname: Bhave
authors.affiliation: Departments of Medicine and Pathology, Cardiovascular Research Institute, University of Vermont, Burlington, VT.
authors.forename: Mary
authors.initials: M
authors.lastname: Cushman
authors.affiliation: Department of Epidemiology, University of Alabama at Birmingham, AL.
authors.forename: Emily B
authors.initials: EB
authors.lastname: Levitan
authors.affiliation: Department of Biostatistics, University of Alabama at Birmingham, AL.
authors.forename: George
authors.initials: G
authors.lastname: Howard
authors.affiliation: Epidemiological Cardiology Research Center, Department of Epidemiology and Prevention, Wake Forest School of Medicine, Winston-Salem, NC Department of Internal Medicine-Cardiology, Wake Forest School of Medicine, Winston-Salem, NC.
authors.forename: Elsayed Z
authors.initials: EZ
authors.lastname: Soliman
mesh_terms: D001741:Black or African American; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000208:ethnology*; D001282:Atrial Flutter / Q000175:diagnosis / Q000208:ethnology*; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D044465:White People
keywords: atrial fibrillation; atrial flutter; epidemiology; risk factors; stroke