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.
Hypothesis: 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.
© 2016 Wiley Periodicals, Inc.