Peak oxygen uptake (VO 2peak ), a measure of aerobic exercise capacity, predicts mortality and morbidity in healthy and diseased individuals. Our aim was to determine VO 2peak years after paediatric allogeneic haematopoietic SCT (HSCT) and to identify associations with baseline patient and donor characteristics, transplantation factors, pulmonary function and self-reported sports activity. In this cross-sectional, population-based study, we measured VO 2peak , spirometry and diffusion capacity of the lung (D LCO ) 3-10 years post HSCT. Z-scores were calculated by reference values from healthy subjects. Self-reported hours of sports activity were obtained by interview. We included 63 patients (mean age (range) 14.4 (7-24) years). HSCT patients exhibited lower mean VO 2peak (−1.42 z-score, 95% confidential interval (−1.7; − 1.1)) compared with healthy subjects (Po 0.001). Sixteen patients (25%) had VO 2peak values o − 1.96 z-score. Low VO 2peak was associated with reduced forced expiratory volume in 1 s (R 2 = 0.11, P = 0.009), reduced D LCO /V A (R 2 = 0.09, P = 0.01) and low physical activity (mean VO 2peak z-score inactive group: − 2.1 vs most active group: − 1.1, P = 0.02). No associations between VO 2peak and diagnosis, donor type or GvHD were found. Although causes for reduced VO 2peak may be multiple, our findings stress the need to focus on physical activity post HSCT to prevent lifestyle diseases and improve quality of life.
INTRODUCTIONThe population of long-term survivors after allogeneic haematopoietic SCT (HSCT) has increased owing to advances in donor selection and improvements in conditioning regimens and supportive care. Improved survival has increased the focus on late effects and quality of life. 1 HSCT may affect multiple organ systems as a result of the toxicity from chemotherapy, TBI and complications including GvHD and infections. 1 In a recent retrospective study, we documented reduced spirometric values in 34% of paediatric patients more than 18 months from HSCT. 2 However, little is known about the potential consequences of reduced pulmonary function for daily life activities and aerobic exercise capacity.Peak oxygen uptake (VO 2peak ) is a measure of physical capacity, which integrates the responses of the cardiovascular, pulmonary and musculoskeletal systems when faced with physical requirements; 3 thus, VO 2peak allows evaluation of abnormalities, which may not be apparent during rest. 4 As a measure of cardiorespiratory fitness, VO 2peak is a powerful predictor of morbidity and mortality in both healthy and diseased individuals. 5,6 In cancer patients, reduced VO 2peak has been associated with fatigue, which is known to reduce the quality of life, especially in children and young adults for whom physical activities are an essential part of the daily routine. 7 A recent systematic review revealed slightly reduced VO 2peak in survivors of childhood leukaemia compared with healthy controls. 8 Although HSCT has been described as the treatmentvariable most consistently associated with redu...