Association of Physical Fitness With the Risk of Atrial Fibrillation: A Systematic Review and Meta‐Analysis

Abstract

Several studies have investigated the role of physical fitness in atrial fibrillation (AF), but the results remain controversial. We aimed to estimate the association between physical fitness and risk of AF. We comprehensively retrieved data from the Cochrane Library, PubMed, and Embase databases until February 29, 2016, for studies evaluating the association of physical fitness with the risk of AF. Data were abstracted from included studies, and effect estimates were pooled using a random-effects model. Six studies with a total of 205 094 participants and 15 919 AF cases fulfilled the inclusion criteria. When physical fitness was assessed as a continuous variable, per incremental increase of physical fitness was associated with a 9% reduced risk of AF (risk ratio [RR]: 0.91, 95% confidence interval [CI]: 0.84-1.00, P = 0.05). When physical fitness was assessed as a categorical variable, the risk of AF was significantly reduced (RR: 0.51, 95% CI: 0.28-0.91, P = 0.02) in individuals with the highest level of physical fitness compared with those with the lowest level. The intermediate vs the lowest level of physical fitness was associated with a 28% reduced risk of AF (RR: 0.72, 95% CI: 0.56-0.93, P = 0.01). The sensitivity analysis indicated that these results were stable. Notably, there was evidence of statistical heterogeneity across studies; therefore, we should interpret the results cautiously. In conclusion, published literature supports that a higher level of physical fitness is associated with a lower risk of AF. Further studies should be performed to confirm these findings.

The obesity paradox for outcomes in atrial fibrillation: Evidence from an exposure‐effect analysis of prospective studies

“…As described previously, we strongly speculate that fitness might mitigate “the obesity paradox” in AF, as based on observations of heart failure and coronary heart disease . Our previous meta‐analysis showed that higher levels of physical fitness are associated with lower risks of recurrent AF, regardless of BMI. Additionally, maintaining or taking up physical activity resulting in improved fitness is associated with a reduced risk of AF and its outcomes.…”

“…Additionally, regardless of BMI, high levels of fitness are associated with better health outcomes (eg, lower mortality and cardiovascular disease risk) . In fact, obesity is significantly associated with an increased risk of cardiovascular death only when combined with low fitness health levels, whereas it is not associated with an increased risk when combined with moderate to high fitness health levels . Currently, available data strongly support the hypothesis that high fitness appears to offset obesity with regard to the negative effects of cardiovascular health .…”

Relation of Body Mass Index With Adverse Outcomes Among Patients With Atrial Fibrillation: A Meta‐Analysis and Systematic Review

“…Physical activity is associated with small reductions in AF risk, even in overweight patients . Our previous meta‐analysis found that a higher level of physical fitness was associated with a lower risk of AF . Specifically, Pathak et al studied obese patients with symptomatic AF who were divided into 3 groups based on their baseline cardiorespiratory fitness.…”

“…65,66 Our previous metaanalysis found that a higher level of physical fitness was associated with a lower risk of AF. 67 Specifically, Pathak et al 68 studied obese patients with symptomatic AF who were divided into 3 groups based on their baseline cardiorespiratory fitness. After 4-year follow-up, the rate of AF recurrence was 88%, 65%, and 34% in the low-, adequate-, and high-fitness groups, respectively.…”

Is There an “Asymptote of Gain” Beyond Which Further Increases in Cardiorespiratory Fitness Convey No Additional Benefits on Mortality and Atrial Fibrillation?

“…A meta-analysis and recent state-of-the-art review of AF indicated an inverse association between fitness and the risk of AF. 8,9 However, it is unclear whether higher fitness results in the greater benefit. Little is known about the point of fitness at which the benefits diminish or there is a decrease in the risk of AF.…”