Determinants of exercise intolerance in breast cancer patients prior to anthracycline chemotherapy

We sought to interrogate previous reports that fitness in breast cancer patients was less than expected for community norms. As compared with healthy control subjects, we observed reduced oxygen consumption capacity in recently diagnosed breast cancer patients prior to treatment. This reduced capacity was associated with smaller heart size and reduced peak exercise cardiac output. This may suggest that reduced exercise conditioning is associated with breast cancer risk. AbstractWomen with early ‐stage breast cancer have reduced peak exercise oxygen uptake (peakVO2). The purpose of this study was to evaluate peakVO2 and right (RV) and left (LV) ventricular function prior to adjuvant chemotherapy. Twenty ‐nine early‐stage breast cancer patients (mean age: 48 years) and 10 age‐matched healthy women were studied. Participants performed an upright cycle exercise test with expired gas analysis to measure peakVO2. RV and LV volumes and function were measured at rest, submaximal and peak supine cycle exercise using cardiac magnetic resonance imaging. PeakVO2 was significantly lower in breast cancer patients versus controls (1.7  ± 0.4 vs. 2.3 ± 0.5 L/min,P = 0.0013; 25 ± 6 vs. 35 ± 6 mL/kg/min,P = 0.00009). No significant difference was found between groups for peak upright exercise heart rate (174 ± 13 vs. 169 ± 16 bpm,P = 0.39). Rest, submaximal and peak exercise RV and LV end‐diastolic and end‐systolic volume index, stroke index, and cardiac...
Source: Physiological Reports - Category: Physiology Authors: Tags: Original Research Source Type: research