Health-related fitness and quality of life following steroid withdrawal in renal transplant recipients

Background. Exercise capacity increases significantly soon after transplantation; however, over time it does not further improve and patients remain low compared to normal levels. The limitations to exercise following transplantation have not been identified, but may be related to immunosuppression therapy regimens that include prednisone. Methods. We studied health-related fitness measures (cardiorespiratory fitness, muscle strength, and body composition) and quality of life in renal transplant recipients randomized into two groups: those using standard maintenance immunosuppression, including prednisone therapy (N=14); and those undergoing rapid withdrawal of steroids using Simulect(R)[interleukin-2 (IL-2) receptor inhibitor] (N=9). Testing was done at 3 and 12 months following transplant and the 12-month data were compared to 15 normal sedentary controls. Results. Compared to those maintained on steroids, the steroid withdrawal group showed greater gains in VO2peak (P=0.05) and quadriceps peak torque (P=0.05) and greater gains in the vitality score and the Physical Composite Scale on the SF-36 questionnaire (P<0.05). At 1 year, all patients had significantly lower exercise capacity compared to the sedentary controls (P=0.01). No differences were observed in body composition, with both patient groups increasing in body weight (primarily body fat) over time. At 12 months, all patients were not different in body fat percentage compared to the sedentary controls. Conclusion. We conclude that prednisone is not the cause for increased body fat following transplantation; however, it may contribute to lower spontaneous improvements in exercise capacity possibly by limiting increases in muscle strength. The low exercise capacity in all transplant recipients studied at 1 year suggests a need for exercise training to optimize physical functioning following transplant.