Cardiometabolic Responses To Exercise Differ By Exercise Type And Intensity In Breast Cancer Patients

Breast cancer treatment often causes negative metabolic health adaptations that increase the risk of cardiovascular disease. PURPOSE: To investigate longitudinal associations between self-reported exercise and cardiometabolic health during the first year of treatment in breast cancer patients. METHODS: Eighty-eight breast cancer patients underwent a fasting blood draw, followed by assessments of waist circumference, weight, blood pressure and physical activity sequentially at baseline, 6 and 12-months post-diagnosis. Insulin, glucose, and triglyceride concentrations were determined via CLIA-approved assay technique. Insulin resistance (HOMA-IR) was established from insulin and glucose concentrations. Multivariate and standard linear regressions were conducted to assess the association between exercise participation, intensity, and type with each cardiometabolic health factor (e.g., insulin, blood pressure). RESULTS: At baseline 48% of participants engaged in exercise compared to 52% who did not, and these groups did not differ by age or body mass index. Exercise participation increased 24% within 12-months post-diagnosis (χ 2 test, p < 0.001). After controlling for potential confounding variables (e.g., age, time) we observed significant inverse associations using all timepoints between exercise participation and insulin (B = -0.30; 95% CI = -0.47 to -0.12), HOMA-IR (B = -0.34, 95% CI = -0.53 to -0.15), blood glucose (B = -0.05, 95% CI = -0.08 to -0.01), and triglycerides (B = -22, 95% CI -39 to -5), but not systolic or diastolic blood pressure. Moderate intensity aerobic exercise participation was inversely associated with insulin (B = -0.32; 95% CI = -0.51 to -0.12), HOMA IR (B = -0.36; 95% CI = -0.57 to -0.14), and triglycerides (B = -20; 95% CI = -39 to -1). Vigorous intensity aerobic exercise was also inversely associated with insulin ( B = -0.48; 95% CI = -0.80 to -0.15), HOMA IR (B = -0.53; 95% CI = -0.89 to -0.18), and triglycerides (B = -42; 95% CI = -74 to -10). Resistance training demonstrated an association with insulin (B = -0.37; 95% CI = -0.64 to -0.10) and HOMA IR (B = -0.38; 95% CI = -0.67 to -0.08) during moderate intensity but not vigorous intensity. CONCLUSION: Moderate resistance and moderate-to-vigorous aerobic exercise may attenuate some breast cancer therapy-induced metabolic dysfunction.