Background: Peak oxygen uptake (VO2peak ) is known as the gold standard measure of cardiopulmonary fitness. We therefore hypothesized that measures of physical health would predict long-term survival in heart transplant recipients (HTx).
Methods: This retrospective study investigated survival in two HTx populations; the cardiopulmonary exercise test (CPET) cohort comprised 178 HTx patients who completed a VO2peak test during their annual follow-up (1990-2003), and the SF-36 cohort comprised 133 patients who completed a quality of life questionnaire, SF-36v1 (1998-2000).
Results: Mean (SD) age in the CPET cohort was 52 (12) yr and 54 (11) yr in the SF-36 cohort. Mean observation time was, respectively, 11 and 10 yr. Mean (SD) VO2peak was 19.6 (5.3) mL/kg/min, and median (IR) physical function (PF) score was 90 (30). VO2peak and PF scores were both significant predictors in univariate Cox regression. Multiple Cox regression analyses adjusted for other potential predictors showed that VO2peak , age, and cardiac allograft vasculopathy (CAV) were the most important predictors in the CPET cohort, whereas age, PF score, smoking, and CAV were the most important predictors in the SF-36 cohort. In Kaplan-Meier analysis, VO2peak and PF scores above the median value were related to significant longer survival time.
Conclusion: Peak oxygen uptake and self-reported physical health are strong predictors for long-term survival in HTx recipients. VO2peak is a crucial measurement and should be more frequently used after HTx.
Keywords: exercise test; heart transplantation; oxygen consumption; physical endurance; physical fitness; quality of life; survival; survival analysis.
© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.