Author(s): SHANLEY, H., DULAI-PIPER, A., MAWN, R., THORP, S., OMAR, H., WARR, T., TURNER, J., MORISSY, H., LAHART, I., Institution: UNIVERSITY OF WOLVERHAMPTON, Country: UNITED KINGDOM, Abstract-ID: 2449

INTRODUCTION:
Postmenopausal women with breast cancer represent a challenging population due to their increased risk for breast cancer development and progression. The beneficial effects of exercise has been demonstrated for women with breast cancer in previous reviews; however, to date, research findings regarding the effects of exercise in postmenopausal breast cancer patients have not been systematically appraised or synthesised. Therefore, we have conducted a systematic review and meta-analysis to examine the insulin- and health-related effects of exercise training in this population.
METHODS:
Cochrane central register of controlled trials (CENTRAL; 2023), PubMed (via MEDLINE), CINHL (via EBSCOhost.com), SPORTDiscus (Via EBSCOhost.com), Scopus (via Elsevier.com) and the OpenGrey database were searched. An English language restriction was applied. Randomised controlled trials (RCTs) which: (1) compared exercise versus no exercise/control in postmenopausal women with a diagnosis of breast cancer (stage I-III), and (2) assessed at least one of our chose outcomes, primary or secondary (circulating levels or markers of insulin resistance, glucose, leptin, adiponectin, oestrogen, body composition, markers of metabolic syndrome, circulating cytokine levels, chemotherapy-related outcomes, and quality of life). Outcomes and measure effects were expressed as either mean differences (MDs) or standardised mean differences (SMDs) with 95% confidence intervals (CIs). A random effects model meta-analysis was conducted. Heterogeneity and publication bias of studies was also assessed.
RESULTS:
Our search revealed a total of 25 articles, reported from 17 RCTs. A meta-analysis of 6 studies showed exercise to elicit no statistically significant effects on circulating levels of insulin (SMD -0.59, 95% CI -1.45 to 0.26). A meta-analysis of 10 studies showed exercise interventions to statistically improve body mass (MD -0.89, 95% CI -2.59 to -1.37). A subgroup analysis of BMI status revealed those who were classed as ‘overweight’ at baseline experienced significant reductions in body mass with exercise (5 studies; MD -1.95, 95% CI -2.93 to -0.97) compared to those who were classed as ‘obese’ (3 studies; MD -2.14 95% CI -7.39 to 3.12) or ‘healthy weight’ (2 studies; MD -2.54 95% CI -11.42 to 6.33).
CONCLUSION:
Based on limited number of studies, our results do not support an insulin lowering effect of exercise-based interventions in postmenopausal women with breast cancer. However, exercise may be an effective intervention for reducing bodyweight. Findings indicate that more research is required to investigate the effects of exercise on insulin resistance in this population.