Center-Based Exercise on Cancer-Related Fatigue in Breast Cancer Survivors During Active Treatment: a Meta-Analysis

Abstract

Background: Cancer-related fatigue (CRF) is a common problem in cancer survivors. Approximately, 80% to 100% of breast cancer survivors during active treatment report CRF symptoms. A growing body of evidence has postulated that center-based exercise interventions (resistance and aerobic training) provide beneficial effects for breast cancer survivors in terms of regaining lost muscle mass as well as improving muscle function and quality of life, including CRF. However, the pooled estimate for the effect of exercise modalities on CRF have not been established yet. Objective: To determine the pooled effect of center-based exercise on CRF in breast cancer survivors during active treatment. Methods: Random-effects model of meta-analysis incorporating the PRISMA statement. The databases of MEDLINE, EMBASE, Ovid, CENTRAL and CINAHL were searched up to December 2013. Risk of bias and quality were evaluated through the PEDro score. A random-effects model was used to calculate Standardized Mean Difference (SMD) with 95% confidence intervals. Statistical heterogeneity was tested with the Chi2 test (P<0.10) and I2 statistics (I2>50%). Subgroup analysis was conducted to establish the pooled effects of each exercise modality (resistance, aerobic and stretching training). Publication bias was evaluated by visual analysis of funnel plot. Results: Six studies were included (n = 936, age = 52.8 (4.1) years old). The included studies presented a low risk of bias (PEDro = 6.1(1.3)). Supervised resistance training produced an overall reduction on (CRF) (SMD= -0.79, 95% IC, -1.49 to -0.10, P = 0.03, I2 = 78%). There were no-significant differences for supervised aerobic exercise (SMD= -0.32; 95% CI, -0.72 to 0.0, I2= 81, P = 0.11). Conclusion: Center-based resistance training reduces CRF in breast cancer survivors. These findings highlight the efficacy of supervised exercise interventions and encourage further research for cancer rehabilitation programs.