Purpose: To investigate the effect of walking meditation on vascular function, aerobic fitness, and quality of life in breast cancer patients receiving anthracycline chemotherapy and compare with the nonexercising control group. Methods: Patients aged 40-60 years with newly diagnosed, histologically confirmed resected stage I-II breast cancer were studied in a parallel randomized controlled trial. The participants were randomly assigned to either the nonexercising control group (n = 15) or the Buddhist walking meditation group (n = 15). All participants received four cycles of anthracycline chemotherapy every 3 weeks starting at 2 weeks before the start of the exercise intervention. The walking meditation group performed home-based mindfulness walking exercises at a moderate exercise intensity for 30 min/session, 3 times/week for 12 weeks. The primary outcome measures were vascular reactivity (flow-mediated dilation [FMD]) and arterial stiffness (brachial-ankle pulse wave velocity [baPWV]). Results: Eleven participants from each group completed the entire study. Analysis of variance with repeated measures indicated that FMD and peak oxygen consumption (VO2peak) decreased in both groups after the initiation of anthracycline chemotherapy (all p < 0.05). After the exercise intervention, FMD, VO2peak, peak stroke volume, and peak cardiac output remained lower in the controls, but improved in the walking meditation group (all p < 0.05). baPWV increased in the control group, while no such change was observed in the walking meditation group. There were no significant changes in blood cortisol, malondialdehyde, and interleukin-6 concentrations in both groups. Overall quality of life decreased after 2 weeks of anthracycline chemotherapy in both groups (all p < 0.05). However, the walking meditation group improved many of these symptoms significantly (all p < 0.05), while no such changes were observed in the control group. Conclusions: Buddhist walking meditation exercise was effective in mitigating cardiotoxicity of anthracycline chemotherapy on vascular function, aerobic fitness, and quality of life in breast cancer patients. Clinical trial registration number: NCT02676531.
Keywords: adjuvant chemotherapy; arterial stiffness; cardio-oncology; endothelial function; mindfulness exercise.