Background: Atrial fibrillation (AF) is the most common type of heart arrhythmia, but the impact of long-term, high-intensity endurance exercise on the risk of AF remains uncertain.
Methods: PubMed, EMBASE, and Cochrane library databases were searched till Nov 2017 to retrieve the articles. The included studies were summarized, pooled odds ratio (OR) and its 95% confidence interval (CI) were calculated. Both fixed and random effects models were used to combine the data. Stratified and logistic meta-regression analyses were performed to explore the sources of heterogeneity across studies.
Results: Nine studies including 2308 athletes and 6593 controls were eligible. Our results showed that the risk of AF was significantly higher in athletes than in general population (OR = 2.34, 95% CI = 1.04-5.28, Pheterogeneity<.001, I = 92.3%). Subgroup analysis based on gender and mean age demonstrated a significantly increased risk in men (OR = 4.03, 95% CI = 1.73-9.42, Pheterogeneity<.001, I = 82.7%) and participants with mean age <60 (OR = 3.24, 95% CI = 1.23-8.55, Pheterogeneity<.001, I = 84.3%). Furthermore, subgroup analysis based on type of athletes demonstrated a significantly increased risk of AF in participants with single type of sport (OR = 3.97, 95% CI = 1.16-13.62, Pheterogeneity = .018, I = 70.4%). Results remained unchanged after performing sensitivity analysis. Meta-regression showed that gender, age, type of study, sample size, and sports mode were unrelated to heterogeneity.
Conclusion: Our study confirmed that the risk of AF was significantly higher in athletes than in general population, especially among men and participants aged <60.