Physical Activity, Exercise Capacity and Quality of Life in Adolescent Heart Transplant Patients

Purpose The primary goal of pediatric heart transplantation (PHTx) is to improve the quality of life (QoL) of patients. National physical activity guidelines for adolescents recommend at least 60-90 minutes of moderate to vigorous physical activity per day. The Physical Activity Questionnaire (PAQ-C/A) for children and adolescents provides general estimates of physical activity levels. Measurement of peak aerobic capacity (VO2peak) using cardiopulmonary exercise testing (CPX) is the gold standard for assessing exercise capacity. Both physical activity and exercise capacity may be important factors that influence reporting a normal QoL. Our aim was to determine if there was a relationship between physical activity, exercise capacity, and QoL in a PHTx adolescent population. Methods This is a single centre retrospective chart review of adolescent (11-18 yrs) PHTx patients. Those who completed a maximal CPX test (RER>1.0), self-report physical activity (PAQ-C or PAQ-A) and QoL (PedsQL and PedsQL-Transplant) questionnaires, as part of their annual assessment, were eligible for inclusion. Results were compared to published age- and sex-matched healthy control data used in our laboratory. VO2peak and QoL were deemed to be normal if results were within two standard deviations of the mean. Pearson correlation coefficients were calculated. Medians and interquartile ranges are reported. Results Thirteen PHTx (10 males) completed a CPX and both QoL questionnaires. The median age was 14.9 yrs (12.3-17.5 yrs). VO2peak=34.5 mL/min/kg (30.2-43.4 mL/min/kg. Only 1 of 13 had an abnormal VO2peak. Total Peds QL score=84.8 (68.5-92.4) with 10 out 13 reporting a normal QoL. The Peds QL-Transplant score=90.5 (84.8-95.1). There was no significant correlation between VO2peak and QoL. The PAQ-C/PAQ-A was completed in 10 HTx. PAQ scores=2.38 (1.59-3.01). Only 2 of 13 met the cut-off point (>2.87) for adequate physical activity. There was a significant correlation between the Peds QL-Transplant QoL and the PAQ (r=0.69; p=0.04) Conclusion PHTx adolescents do not meet their required physical activity recommendations. Despite this, they have low normal exercise capacity and report a normal QoL. Efforts to engage adolescents to increase their physical activity should be encouraged.