Submit Manuscript    >>    Login | Register


  •    Vigorous Exercise May Increase the Risk of Atrial Fibrillation?
    Darbhamulla V Nagarajan, MRCP.

    Association between vigorous exercise and AF has previously been reported, however the data is mainly limited to case series and small case controlled studies. A recent sub-study of the Physician Health Study by Anthony Aizer looked at this very specific question.

    A Prospective observational study consisting of a cohort of male physicians enrolled in to Physicians Health Study in 1982 published in American Journal of Cardiology (Aizer A et al. Relation of Vigorous Exercise to Risk of Atrial Fibrillation. Am J Cardiol 2009;103:1572-1577). Participants were 40-84 years old with no past medical history of myocardial infarction, stroke, transient ischemic attack or cancer at the time of enrolment in 1982. Information on health status, risk factors for cardiovascular disease and atrial fibrillation, dietary and lifestyle factors was collected by questionnaires. Physicians who did not complete the three year follow-up questionnaire or who reported a diagnosis of cardiovascular, cerebrovascular or peripheral vascular disease at 3 years were excluded from analyses. Information about exercise habits was collected 3 and 9 years after enrollment. Vigorous exercise was defined as any exercise that was strenuous enough to break sweat. Questionnaire on exercise habits for physicians engaging in vigorous exercise included frequency, duration and type of exercise.   Physicians were asked at 15, 17, 18 and 19 years after enrollment if they had ever been diagnosed with AF and the date of diagnosis.

    After adjustment for multiple potentially confounding lifestyle factors and health conditions, higher frequency of participation in a regular program of vigorous exercise at 3 years was associated with a modestly increased risk of developing AF. Participants who exercised 5 to 7 times per week had the greatest risk of developing AF compared with those who did not exercise (p=0.025). The relation between vigorous exercise and AF was no longer significant when exercise habits were updated at 9 years. The increase in risk decreased with increasing age. In men aged ≥ 50 years no association was found and in men aged ≤ 50 years, and who exercised 5-7 times per week, the association was statistically significant in all analyses. Secondary analysis found that frequency of jogging was most strongly associated with development of AF. Participants who jogged ≥ 5 days per week had a 53% increased risk of developing AF compared to participants who did not exercise. When joggers were excluded, the relation between vigorous exercise and AF was no longer present.

    This large prospective cohort study confirms the association between vigorous exercise and risk of AF. Investigators hypothesize increased pasympathetic tone in joggers and decreased parasympathetic tone with aging as one of the possible explanations for increased risk and no association with AF in these cohorts respectively. Some of the limitations of this study include lack of precise objective measurement of physical activity, possible under detection of AF due to self reporting and the selective nature of the cohort.

Biosense Webster
event date
Introduction to AFib
Ablation Specialist

View Ablation Specialists