Effects of aerobic exercise on cancer-related fatigue in breast cancer patients receiving chemotherapy: a meta-analysis

Increasing scientific evidences suggest that aerobic exercise may improve cancer-related fatigue in breast cancer patients, but many existing studies have yielded inconclusive results. This meta-analysis aimed to derive a more precise estimation of the effects of aerobic exercise on cancer-related fatigue in breast cancer patients receiving chemotherapy. The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched from inception through July 1, 2013 without language restrictions. Crude standardized mean difference (SMD) with 95 % confidence interval (CI) was calculated. Twelve comparative studies were assessed with a total of 1,014 breast cancer patients receiving chemotherapy, including 522 patients in the aerobic exercise group (intervention group) and 492 patients in the usual care group (control group). The meta-analysis results revealed that the Revised Piper Fatigue Scale (RPFS) scores of breast cancer patients in the intervention group were significantly lower than those in the control group (SMD=-0.82, 95% CI=-1.04 ∼ -0.60, P<0.001). However, there was no significant difference in the Functional Assessment of Chronic Illness Treatment-Fatigue scale (FACIT-F) scores between the intervention and control groups (SMD=0.09, 95% CI=-0.07 ∼ 0.25, P=0.224). Subgroup analysis by ethnicity indicated that there were significant differences in RPFS and FACIT-F scores between the intervention and control groups among Asian populations (RPFS: SMD=-1.08, 95% CI=-1.35 ∼ -0.82, P<0.001; FACIT-F: SMD=1.20, 95 % CI=0.70 ∼1.71, P<0.001), but not among Caucasian populations (all P>0.05). The current meta-analysis indicates that aerobic exercise may improve cancer-related fatigue in breast cancer patients receiving chemotherapy, especially among Asian populations.