title: Impact of Awareness and Patterns of Nonhospitalized Atrial Fibrillation on the Risk of Mortality: The Reasons for Geographic And Racial Differences in Stroke (REGARDS) Study.
abstract: BACKGROUND
  Although mortality associated with atrial fibrillation (AF) has been reported to decrease over prior decades, the mortality risk of asymptomatic, nonhospitalized AF has not been examined.
  
  
  OBJECTIVE
  Asymptomatic, nonhospitalized AF is associated with an increased risk of death.
  
  
  METHODS
  This analysis included 25,976 participants (mean age, 65 ± 9.4 years; 55% female; 38% black) from the Reasons for Geographic And Racial Differences (REGARDS) study. Atrial fibrillation was detected on the baseline electrocardiogram (ECG AF) or by self-reported history. Atrial fibrillation unawareness was defined as present if ECG evidence of the arrhythmia was detected but no self-reported history was reported. All-cause mortality was confirmed during follow-up through March 31, 2014.
  
  
  RESULTS
  A total of 2208 (8.5%) participants had AF at baseline (ECG: n = 371/17%; self-reported: n = 1837/83%). Over a median follow-up of 7.6 years, 3481 deaths occurred. In a multivariable Cox regression model, AF was associated with a 32% increased risk of mortality (95% confidence interval [CI]: 1.19-1.46). Risk of death was higher among those with ECG AF (hazard ratio: 1.71, 95% CI: 1.42-2.07) compared with self-reported cases (hazard ratio: 1.15, 95% CI: 1.03-1.29). Those who were unaware of their AF diagnosis had a 94% increased risk of death (95% CI: 1.50-2.52) compared with AF participants who were aware of their diagnosis.
  
  
  CONCLUSIONS
  Asymptomatic, nonhospitalized AF is associated with an increased risk of mortality in the general population. Mortality is higher in those with ECG-confirmed cases and among those who are unaware of their diagnosis.
authors.affiliation: Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina.
authors.forename: Wesley T
authors.initials: WT
authors.lastname: O'Neal
authors.affiliation: Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, North Carolina.
authors.forename: Jimmy T
authors.initials: JT
authors.lastname: Efird
authors.affiliation: Department of Biostatistics, Department of Epidemiology and Biostatistics, Dornsife School of Public Health, Drexel University, Philadelphia, Pennsylvania.
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Judd
authors.affiliation: School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Leslie A
authors.initials: LA
authors.lastname: McClure
authors.affiliation: Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Virginia J
authors.initials: VJ
authors.lastname: Howard
authors.affiliation: Department of Biostatistics, Department of Epidemiology and Biostatistics, Dornsife School of Public Health, Drexel University, Philadelphia, Pennsylvania.
authors.forename: George
authors.initials: G
authors.lastname: Howard
authors.affiliation: Department of Internal Medicine, Cardiology Section, Wake Forest School of Medicine, Winston-Salem, North Carolina.|Epidemiological Cardiology Research Center (EPICARE), Department of Epidemiology and Prevention, Wake Forest School of Medicine, Winston-Salem, North Carolina.
authors.forename: Elsayed Z
authors.initials: EZ
authors.lastname: Soliman
mesh_terms: D000368:Aged; D058070:Asymptomatic Diseases; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000208:ethnology / Q000401:mortality; D001364:Awareness; D002423:Cause of Death; D016009:Chi-Square Distribution; D004562:Electrocardiography; D005260:Female; D007722:Health Knowledge, Attitudes, Practice / Q000208:ethnology; D054624:Health Status Disparities; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis / Q000453:epidemiology* / Q000208:ethnology / Q000401:mortality; D013997:Time Factors; D014481:United States / Q000453:epidemiology