The effect of aerobic exercise on the metabolic risk profile of breast cancer survivors 2-6 months post chemotherapy.

Abstract

244 Background: Current literature suggests that weight gain during treatment for breast cancer is associated with a poorer prognosis and an increased risk of developing secondary health problems such as the metabolic syndrome (MetSyn). Physical activity (PA) can alter features of the MetSyn and improve body composition by reducing abdominal adiposity. We report metabolic results of a prospective randomized controlled trial (PEACH trial; Walsh JM, et al. [2010] BMC Cancer. 10[42]) which examines the effect of an exercise intervention on the metabolic risk profile of breast cancer survivors 2-6 months post chemotherapy. Methods: All subjects gave written informed consent and were randomized to an 8-week, twice weekly aerobic exercise intervention programme or a usual care control group consisting of routine medical advice about PA. The five clinical features of the MetSyn were measured: waist circumference (WC), resting blood pressure (BP), triglycerides, high-density lipoprotein cholesterol (HDL-C) and fasting glucose. Insulin resistance was estimated by the homeostatic model assessment (HOMA). Statistical analysis was carried out using independent sample t-tests with significance set at p < 0.05. Results: Twenty-six breast cancer survivors participated (mean (± SD) age 48.13 (8.75) years). At baseline, 50% (n = 13) of subjects were overweight and 23.1% (n = 6) were obese, with 73.1% (n = 19) centrally obese. 34.6% (n = 9) of subjects were classified with the MetSyn. There were no significant differences between groups at baseline. Intention-to-treat analysis showed no significant changes, however, analysis of those who adhered to > 70% of the supervised exercise intervention showed a significant improvement in WC when compared to the control group (p < 0.05). Conclusions: Results show that an 8-week aerobic exercise intervention significantly reduced WC but did not modify other features of the MetSyn. The decrease in WC demonstrated by this short intervention may have important implications in terms of improving survival and the metabolic risk profile of breast cancer survivors. Final follow-up assessments are ongoing and will enable change in WC over time to be evaluated further.