α1-Antitrypsin deficiency associated with increased risk of atrial fibrillation in two large populations

<bold>Background:</bold> α₁-Antitrypsin deficiency (AATD) is known to cause early onset emphysema due to loss of elastic tissue within the lungs. The heart tissue also contains elastic fibers, and AATD may also affect heart tissue remodeling and susceptibility to atrial fibrillation. <bold>Aim and objective:</bold> To investigate whether AATD is associated with increased risk of atrial fibrillation in the Danish population. <bold>Methods:</bold> In a nationwide nested cohort we identified 2,233 individuals with AATD and 22,133 controls matched on sex, age and municipality. In a population-based cohort we included 102,481 individuals from the Copenhagen General Population Study and an additional 187 individuals from the Danish α₁-Antitrypsin Deficiency Registry. We recorded hospitalizations, Digoxin medication use and deaths related to atrial fibrillation during a median follow-up time of up to 67 years. <bold>Results:</bold> Individuals with versus without AATD had increased risk of hospitalization due to atrial fibrillation in the nationwide cohort (adjusted hazard ratio:1.99; 95% CI:1.71-2.32) and in the population-based cohort (1.51; 95% CI:1.09-2.09). Individuals with versus without AATD also had an increased risk of Digoxin use in the nationwide cohort (2.11, 95% CI:1.42-3.14). Lastly, individuals with versus without AATD had increased risk of atrial fibrillation-related death in the nationwide cohort (2.60, 95% CI:1.65-4.11). <bold>Conclusion:</bold> Individuals with AATD have an increaed risk of atrial fibrillation hospitalization and atrial fibrillation-related mortality in the Danish Population.