Sport practice and the risk of lone atrial fibrillation:: A case-control study

Background: Lone atrial fibrillation (LAF) is characterized by the presence of atria] fibrillation in the absence of structural heart disease or other identifiable cause of arrhythmia. In a recent study, we reported sport practice to be more frequent in LAF patients than in the general population. The aim of the study was to determine the association between sport practice and the prevalence of LAF in men. Methods: An age-matched case-control study was designed. Cases were identified from consecutive patients who attended an outpatient clinic; 51 men with LAF were included, 20 of them with vagal characteristics. Controls were selected from the general population (n = 109). A questionnaire to assess former and current sport practice and the number of lifetime hours of sport practice was administered. Conditional logistic regression was used for statistical analysis. Results: The proportion of patients with LAF who reported current sport practice (31%) was higher than that observed in controls (14%). In the logistic regression, current practice of sport was associated with a higher prevalence of LAF (OR=3.13; 95% CI: 1.39-7.05). The practice of more than 1500 lifetime hours of sport appears to be the threshold for the observed association. Current practice of sport with a lifetime practice greater than 1500 h was associated with LAF (OR=2.87; 95% CI: 1.20-6.91). Conclusion: In men, the combination of current and prolonged lifetime sport practice is associated with higher risk of LAF. (c) 2005 Elsevier Ireland Ltd. All rights reserved.