Physical Activity and Atrial Fibrillation Risk: It's Complicated; and Sex Is Critical

Stanley Nattel


Eur Heart J. 2020;41(15):1487-1489. 

In This Article

Results From the UK Biobank

In this issue of the European Heart Journal, Elliott et al. report the results of a study exploiting the very extensive and well-structured UK Biobank to provide a detailed and elegant analysis of the relationship between levels of physical activity and AF risk.[4] Data were obtained from 402 406 individuals who completed self-reported physical activity screening questionnaires at baseline. Analysis of the information in the questionnaire allowed for the estimation of the total weekly physical activity at baseline (in MET-min/week), as well as the proportion attributable to vigorous physical activity. Participants were followed (median follow-up of 7 years) for arrhythmia endpoints with the use of national electronic health record databases. In addition to the occurrence of AF and atrial flutter (which are the focus here), they examined the occurrence of ventricular arrhythmias and bradyarrhythmic events.

As previously reported in the literature,[2] the authors noted a predominantly protective effect of regular physical activity against AF/flutter events. However, their large database and detailed quantitative information on activity levels allowed the authors to identify sex-related complexity within the data. Women showed a more pronounced risk reduction with activity than men, as well as a protective effect over the entire range of physical activity levels examined, with statistically significant reductions in AF risk up to 2500 MET-min/week. For men, however, increasing physical activity was only protective against AF to a level of 1500 MET-min/week; beyond that, the protective effect was lost. Furthermore, there was a statistically significant interaction between sex and vigorous activity effects. In women, a beneficial anti-AF effect was observed for vigorous exercise, whereas for men, there was a progressive increase in AF risk with greater amounts of vigorous physical activity, with a statistically significant 12% risk enhancement at 5000 MET-min/week.