BACKGROUND AND AIMS
Contemporary data suggest endurance athletes are at an increased risk of developing atrial fibrillation (AF) when compared with the general population.1 Cardioembolic events such as stroke are a well-established complication of untreated AF.
The CHA2DS2-VASc score is used in clinical practice to risk-stratify those with AF. Due to a reduction in traditional cardiovascular risk factors associated with exercise, many athletes will have a low CHA2DS2-VASc score of 0–1, indicating no need for anticoagulation. However, endurance athletes demonstrate phenotypes such as atrial dilatation, which are not captured in CHA2DS2-VASc and are themselves associated with an increased risk of stroke in the general population.2 It may be that athletes who develop AF are not appropriately risk-stratified by CHA2DS2-VASc. The aim of this study was to estimate the risk of stroke in veteran endurance athletes who develop atrial fibrillation (≥40 years).
MATERIALS AND METHODS
A questionnaire was broadcasted through social media and sports clubs. Individuals who had competed in at least one competitive event and were ≥40 years old were included. Self-reported demographic, past medical history, and training history data were collected and a CHA2DS2-VASc was calculated. Multivariable binary logistic regression was used to assess variables associated with AF and stroke.
The survey received 1,002 responses from 41 countries across Africa, Asia, Australasia, Europe, and North and South America. In total, 942 were included in the final analysis with an average age of 52.4±8.5 years and 83.7% were male. The most frequently participated sports were cycling (n=677 [71.9%]), running (n=558 [59.2%]), and triathlon (n=245 [26.0%]). There were 190 (20.2%) individuals who reported AF and 26 (2.8%) individuals who reported stroke, of which 14 (53.9%) had AF. Of those with stroke and AF, 11 were diagnosed with AF following a stroke. Lifetime exercise dose (odds ratio [OR]: 1.02; 95% confidence interval [CI]: 1.00–1.03; p=0.02) and swimming (OR: 1.56; 95% CI: 1.02–2.39; p=0.04) were associated with AF in multivariable analysis. AF (OR: 4.18; 95% CI: 1.80–9.72; p<0.01) was associated with stroke, even in individuals with a CHA2DS2-VASc of 0 or 1 (OR: 4.20; 95% CI: 1.83–9.66; p<0.01).
This survey suggests that the risk of stroke in veteran endurance athletes who develop AF is not negligible, even in those deemed to be at low risk by commonly used risk scores. Despite this, the authors found the rate of anticoagulation to be lower than expected. Longitudinal studies are needed to substantiate these findings to inform individualised decisions about anticoagulation.