Cardiorespiratory fitness predicts cardiovascular health in breast cancer survivors, independent of body composition, age and time post-treatment completion

Abstract

Breast cancer treatment may increase non-cancer related mortality risk due to unintended cardiovascular consequences. The aim of this study was to investigate the strongest correlate of cardiovascular health (CVH) in female breast cancer survivors, cardiorespiratory fitness or fatness. Fifty-one women (59 ± 9years, BMI 26.4 ± 4.8kg/m2) previously diagnosed and treated for primary breast cancer were assessed using pulse wave analysis to determine central arterial wave reflection (augmentation index, AIx) and central systolic blood pressure (cSBP). A composite Z score calculated which incorporated central double product and AIx, as an indicator of CVH. Dual energy X-ray absorptiometry was used to obtain total body fat percentage (BF%). Cardiorespiratory fitness was determined using the single-stage walk test to predict maximal oxygen uptake ([Formula: see text]). Linear regression analysis revealed that fitness was associated with AIx after adjusting for BF%, age and time post-treatment completion (β = -0.271, p = 0.010). A significant association between BF% and AIx after adjusting for fitness and age was found (β = 0.166, p = 0.0005); however, this association was lost when time post-treatment was included in the model (β = 0.166, p = 0.167). Both fitness (β = -0.347, p = 0.0005) and BF% (β = 0.333, p = 0.013) were independently associated with CVH in the fully adjusted model. This study provides evidence for an association between cardiorespiratory fitness and cardiovascular health in female breast cancer survivors. While fatness may be associated with cardiovascular health, it appears to be more strongly associated with age.