The Effect of Physical Activity on Risk for Atrial Fibrillation in Women

Women can perform up to 50 metabolic equivalents task (MET)-hours per week (h/w) of moderate to vigorous physical activity (PA) to reduce risk for atrial fibrillation (AF), but likely should not exceed that level. These findings, from a systematic review and meta-analysis, were published in International Journal of Cardiology.

Investigators from the Athens General Hospital in Greece searched publication databases through May 2022 for studies of PA among women with the outcome of AF risk. A total of 15 studies were included in this analysis.

The studies were conducted in the United States (n=7), South Korea (n=3), Norway (n=2), Sweden (n=1), the Netherlands (n=1), and the United Kingdom (n=1).

The studies evaluated PA using self-assessment (n=13) or a wearable device (n=2) and the studies defined AF by diagnosis (n=6), electrocardiogram (n=6), via medical records (n=2), or use of flecainide or sotalol (n=1).

The study population comprised 1,821,422 women and sample sizes ranged from 2675 to 1,023,895. The women had a median age of 36.8 to 78.2 years; however, 7 studies did not report age. Overall, the incidence rate of AF was 3.7% during follow-ups ranging from 3.5 to 20 years.

The relationship between PA and AF risk was nonlinear (P <.0001). The nonlinear relationship between PA and AF risk was still observed when low-quality studies were removed (P <.0001), when only studies that used METs to quantify PA were included (P <.0001), or when MET hours were subtracted or added to PA categories (P <.0001). All comparisons had low to moderate heterogeneity (I² range, 13.7%-45.1%).

In the final analysis, the J-shaped dose response curve indicated that risk for incident AF increased when PA levels reached 70 to 80 MET-h/w (P <.0001; I², 78.5%), indicating that a PA level of 50 MET-h/w can likely be safely recommended for women to reduce their future AF risk.

The major limitation of this analysis is that most studies quantified PA by self-reported questionnaires and not by objective measures.

“In this systematic review and meta-analysis we demonstrated that weekly PA is inversely associated with the risk for future AF in the female general population,” the study authors wrote. “This relationship is far from being a straightforward linear dose-response effect; even low levels of regular exercise can provide comparable benefit to that seen in highly active individuals.”