Effectiveness of aerobic exercise intervention on cardiovascular disease risk in female breast cancer: a systematic review with meta-analyses

Cardiovascular disease (CVD) has become the leading cause of competitive mortality in female breast cancer (BC). Regular aerobic exercise (AE) has been widely accepted as an effective intervention to reduce cardiovascular risk in a variety of different clinical conditions. This study is aimed at evaluating the efficacy and safety of AE on cardiovascular risk factors in female BC and assessing the quality of the synthesized evidence. We searched five English databases (Cochrane Library, PubMed, Embase, Scopus, and Web of Science) from inception to January 2023. Randomized controlled trials (RCTs) and cohort trials studying the effects of AE intervention on cardiovascular disease risk in female breast cancer were included. We used Stata 16 for data synthesis, Risk of Bias 2, and the Newcastle–Ottawa Scale for methodological quality evaluation and assessed the certainty of the synthesized evidence in the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Forty RCTs and 6 cohort trials involving 44,877 BC patients showed AE reduced the incidence of CVD events by 29.4% [risk ratio (RR) = 0.706, 95% confidence interval (CI) (0.659, 0.757), low certainty] and coronary artery disease events by 36% [RR = 0.640, 95% CI (0.561, 0.729), low certainty]. AE improved LVEF, and reduced weight and hip circumference. The subgroup analysis results showed that nonlinear AE increased VO2max by 5.354 ml·kg·min−1 [mean difference (MD) = 5.354, 95% CI (2.645, 8.062), very low certainty] and reduced fat mass by 4.256 kg [MD = 4.256, 95% CI (-3.839, -0.094), very low certainty]. While linear AE reduced low-density lipoprotein cholesterol (LDL-C) by 8.534 mg/dL [MD = -8.534, 95% CI (-15.511, -1.557), low certainty]. The sensitivity analysis results showed that each trial did not affect the impact index of the highly heterogeneous outcomes. Our study indicates that AE has a positive effect in reducing cardiovascular risk factors. The individualization principle of AE deserves more attention in the future. This will provide new ideas to reduce CVD events and improve the quality of life in female BC patients. However, further research on AE in female BC should take into account long-term and well-designed administration to draw definitive conclusions.