Exercise Capacity Inversely Correlated with Atrial Fibrillation Incidence, Study Finds

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A study of more than 15,000 individuals suggests regular physical activity may help prevent the development of atrial fibrillation, as well as the incidence of stroke and MACE.

Credit: Andrea Piacquadio/Pexels

Exercise capacity was inversely correlated with the incidence of atrial fibrillation (AF) and stroke across fitness levels across an analysis of more than 15,000 patients.¹

The research, presented at the European Society of Cardiology (ESC) Congress 2023, suggests a better exercise performance is linked to a lower risk of AF incidence, and a lower incidence of ischemic stroke and major adverse cardiovascular events (MACE).

“This was a large study with an objective measurement of fitness and more than 11 years of follow-up,” said study author Shih-Hsien Sung, MD, PhD, National Yang-Ming Chiao Tung University in Taiwan.² “The findings indicate that keeping fit may help prevent atrial fibrillation and stroke.”

The most common heart rhythm disorder, AF affects more than 40 million people worldwide. It is associated with increased risks of cardiovascular diseases, quality of life, mortality, and global health expenditures. Patients diagnosed with the condition experience a five-fold higher risk of stroke, compared to peers without AF.³

Many cardiovascular risk factors are related to the development of AF, but lifestyle behaviors, such as regular exercise and good cardiorespiratory fitness, could help modify the risk factors and reduce the incidence of AF. Sung and the investigative team analyzed the relationship between better exercise performance and the risk of incident atrial fibrillation and subsequent comorbidities.¹

Over a period from 2003 to 2012, the team retrospectively included 19,680 consecutive patients without a previous diagnosis of AF who were referred to exercise treadmill testing. The analysis accessed all baseline characteristics and exercise parameters during exercise testing in all enrolled participants.

Using multivariable Cox proportional hazards models, investigators analyzed the independent association between exercise performance and the risk of new-onset AF, risk of ischemic stroke, and MACE, after adjusting for confounding factors (age, sex, cholesterol level, kidney function, prior stroke, hypertension, and medications). A cubic spline regression model assessed the risk of new-onset AF across fitness levels in the analysis.

Overall, 15,450 participants with a mean age of 54.9 years and more than half being (59%) male were included in the analysis. Over a median follow-up of 137 months, 515 (3.33%) cases of new-onset AF were found by investigators.

Each 1 peak achieved a metabolic equivalent (MET) increase in exercise treadmill testing was associated with an 8% lower risk of AF incidence (hazard ratio [HR], 0.92; 95% CI, 0.88 - 0.97), a 12% lower risk of ischemic stroke incidence (HR, 0.88; 95% CI, 0.83 - 0.94), and a 14% lower risk of MACE (HR, 0.86; 95% CI, 0.84 - 0.88), after adjusting for confounding factors.

Participants were divided into 3 fitness levels according to METs achieved during the treadmill test: low (less than 8.57 METs), medium (8.57 to 10.72), and high (more than 10.72). The probability of remaining free from atrial fibrillation over a 5-year period was 97.1%, 98.4%, and 98.4% in the low, medium, and high fitness groups, respectively.

Subgroup analyses revealed the peak achieved METs during exercise testing were significantly associated with the risk of new-onset AF across subgroups, including age, body mass index, and underlying disease. Investigators observed significant interactions in the age subgroup (P for interaction .0047) and the subgroup stratified by the presence of chronotropic incompetence (P for interaction 0.0212).

Sung and colleagues suggest further research is necessary to better elucidate the underlying mechanisms between exercise capacity and AF incidence.

References

CT Lu, SH Sung. Exercise performance and the risk of incident atrial fibrillation. Presented at the European Society of Cardiology Congress 2023. Amsterdam, the Netherlands. August 25-August 28.
Escardio. Keep fit to avoid heart rhythm disorder and stroke. EurekAlert! August 22, 2023. Accessed August 22, 2023. https://www.eurekalert.org/news-releases/998897.
Kornej J, Börschel CS, Benjamin EJ, Schnabel RB. Epidemiology of Atrial Fibrillation in the 21st Century: Novel Methods and New Insights. Circ Res. 2020;127(1):4-20. doi:10.1161/CIRCRESAHA.120.316340