Effects of exercise interventions on cancer-related fatigue in breast cancer patients: An overview of systematic reviews

Abstract

Objective This overview of systematic reviews (OoSRs) aims to critically appraise and consolidate evidence from current systematic reviews (SRs)/meta-analyses on the effects of exercise interventions on cancer-related fatigue (CRF) in breast cancer patients. Methods SRs/meta-analyses that focused on exercise intervention for CRF in breast cancer and relevant grey literature were searched in electronic databases, through September 2021. Methodological quality of the included SRs was appraised using A MeaSurement Tool to Assess systematic Reviews II (AMSTAR II). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to calculate the grading of outcomes in the included SRs. Stata 16.0 software was utilized for data analysis.Results Twenty-nine reviews were located. The overall methodological quality was unsatisfactory, with only three reviews rated as high quality. The evidence quality was generally low, with no high-quality SRs identified via the GRADE. Moderate certainty evidence indicating exercise could improve fatigue in breast cancer patients (SMD=-0.40 [95%CI -0.58, -0.22]; P=0.0001). Subgroup analysis based on the types of exercise showed that yoga (SMD=-0.30 [95%CI -0.56, -0.05]; I2=28.7%) and aerobic exercise (SMD=-0.29 [95%CI -0.56, -0.02]; I2=16%) had a significantly better effect on CRF in breast cancer patients; exercising for over six months (SMD=-0.88 [95%CI -1.59, -0.17]; I²=42.7%; P=0.0001), three times per week (SMD= -0.77 [95%CI -1.04, -0.05]; I²= 0%; P=0.0001), and for 30 to 60 minutes per session (SMD=-0.81 [95%CI -1.15, -0.47];I²=42.3%; P=0.0001) can contribute to a moderate improvement of CRF. Supervised exercise (SMD=-0.48 [95%CI -0.77, -0.18]; I²=87%; P=0.001) was shown to relieve CRF.Conclusion Exercise played a favorable role in alleviating CRF in breast cancer. Yoga was recommended as a promising exercise for CRF management in majority of the included studies. Exercising for at least three times per week with 30 to 60 minutes per session could be recommended as a suitable dosage for achieving improvement in CRF. Supervised exercise was found to be more effective in alleviating CRF than unsupervised exercise. More rigorously designed clinical studies are warranted to generate more robust evidence to support the use of exercise interventions for CRF management in breast cancer patients.PROSPERO registration of the study protocol: CRD42020219866