Medically Supervised Exercise and Inflammation in Breast Cancer Survivors with Metabolic Syndrome: A Meta-Analysis.

BACKGROUND

Postmenopausal women with breast cancer and coexisting metabolic syndrome are at increased risk of breast cancer-related lymphedema (BCRL) and chronic systemic inflammation. Medically supervised exercise (MSE) has emerged as a promising non-pharmacological intervention to mitigate these complications. This systematic review and meta-analysis aimed to evaluate the effects of MSE on BCRL severity, inflammatory biomarkers, and quality of life (QoL) in this high-risk population.

METHODS

A systematic search was conducted across PubMed, Cochrane Library, and Scopus up to May 2024 for randomized controlled trials (RCTs) involving postmenopausal breast cancer survivors with metabolic syndrome who participated in MSE programs. Outcomes of interest included BCRL severity, inflammatory markers (hs-CRP, IL-6, TNF-α), and QoL. Data extraction and risk of bias assessment were performed independently by two reviewers following PRISMA 2020 guidelines. Pooled effect sizes were calculated using a random-effects model. Heterogeneity was assessed with the I2 statistic, and evidence quality was evaluated using GRADE.

RESULTS

Fifteen RCTs (n = 1,197) were included. MSE significantly reduced systemic inflammatory markers (mean difference = 0.31; 95% CI: 0.05 to 0.57; P = 0.02) with moderate heterogeneity (I² = 50.4%). Subgroup analyses showed moderate-quality evidence for reductions in IL-6 and TNF-α, though results varied across studies. Evidence for CRP reduction was very low due to high heterogeneity and risk of bias. Improvements in QoL and reductions in lymphedema volume were also reported in several studies.

CONCLUSIONS

MSE appears effective in reducing systemic inflammation and improving QoL among postmenopausal breast cancer survivors with metabolic syndrome. However, evidence for specific biomarkers remains limited. Further high-quality, standardized RCTs are needed, especially in underrepresented regions such as sub-Saharan Africa, to guide global implementation of MSE in cancer rehabilitation.