The Effect of Exercise on Cardiotoxicity in Women with Breast Cancer Receiving Anthracycline-Based Chemotherapy: A Systematic Review and Meta-Analysis

Introduction: Breast cancer is the most common cancer in women with a 5-year survival over 90%. However, anthracycline-based chemotherapy causes significant cardiotoxicity often requiring discontinuation of chemotherapeutic regimen among breast cancer survivors. We conducted a systematic review and meta-analysis to evaluate the efficacy of exercise training in mitigating anthracycline-related cardiotoxicity among women with breast cancer. Methods: We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases. The outcomes of interest were left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), early to atrial filling velocity (E/A) ratio, maximal oxygen consumption (VO2 max), and cardiac output (CO). We used the Cochrane risk-of-bias tool for randomized trials (RoB 2) to assess the risk of bias in individual studies. Results: We identified a total of 596 articles with 5 trials included in the final analysis. Exercise training was associated with an increase in VO2 max compared with no exercise training (mean difference, 3.95 [95% CI, 0.63-7.26]; I-2 = 99.68%). Other cardiovascular outcomes such as LVEF (mean difference, 1.76 [95% CI, -1.95 to 5.46]; I-2 = 99.44%), GLS (mean difference, 0.30 [95% CI, -0.49 to 1.10]; I-2 = 96.63%), E/A ratio (mean difference, 0.05 [95% CI, -0.05 to 0.15]; I-2 = 94.16%), and CO (mean difference, 0.38 [95% CI, -0.91 to 1.66]; I-2 = 99.73%) are similar between patients who underwent exercise training and those who did not. Conclusions: Exercise was associated with an improvement in maximal oxygen uptake among women with breast cancer receiving anthracycline-based chemotherapy.