Impaired lung function predicts atrial fibrillation

The likelihood of atrial fibrillation (AF) appears to be elevated in the context of weaker pulmonary function, a recent study has shown.

The study included 9,631 participants (median age, 50 years; 48.1 percent male) in whom AF was identified using electrocardiography or self-reports of physician diagnoses, either at baseline or throughout the study period. Lung function was measured according to the forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC).

At baseline, AF was present in 59 participants, yielding a prevalence rate of 0.6 percent. This was significantly higher in the lowest vs highest quartile of FEV1% predicted (1.2 percent vs 0.3 percent; p<0.001). This translated to an elevated likelihood of developing the condition (adjusted odds ratio [OR], 5.92, 95 percent CI, 2.22–15.77).

FVC% predicted at baseline had the same effect on AF risk (adjusted OR, 5.40, 2.06–14.20).

During the follow-up period, a total of 162 new AF cases were reported, leading to an incidence rate of 1.7 percent. Kaplan-Meier curves showed that AF incidence was significantly elevated in the lowest vs highest quartile of FEV1% predicted (2.1 percent vs 1.5 percent; log-rank p=0.042). No such effect was reported for FVC% predicted.

Cox regression analyses confirmed these findings. FEV1% predicted was significantly associated with a greater risk of incident AF (adjusted hazard ratio [HR], 1.59, 1.02–2.50), while FVC% predicted was not (adjusted HR, 1.34, 0.86–2.09).