#6919 Cardiorespiratory Fitness and Mortality Risk in Patients Receiving Hemodialysis: A Prospective Cohort

Abstract

Background and Aims Kidney failure reduces life expectancy by one-third compared with the general population, and cardiovascular complications and poor cardiorespiratory fitness (CRF) are the main causes. We aimed to evaluate the association between severe CRF and all-cause mortality risk in HD patients. Method This observational prospective cohort study followed-up patients receiving HD from August 2015 until March 2022. Cardiorespiratory fitness was evaluated through the cardiopulmonary exercise test and the peak of oxygen uptake (VO2peak) value was used to determine severe CRF (<15 mL·kg−1·min−1). Cox regression and Univariate Kaplan-Meier evaluated its association with mortality risk and survival rate. Results Forty-eight patients were followed-up for a median of 33.0 [14.3 – 49.3] months. A total of 26 patients had severe CRF. During the follow-up period, 11 patients (22.92%) experienced all-cause mortality. From these, eight (30.8%) had severe CRF. Even so, severe CRF was not associated with crude death rates for patients stratified by CRF levels (p = 0.189), neither in unadjusted (HR 2.35; CI 95% 0.61−9.15) and adjusted (HR 1.29; CI 95% 0.30−5.56) Cox proportional hazard models. As a continuous variable, each mL·kg−1·min−1 increase in VO2peak was not associated with mortality risk (HR 0.94; CI 95% 0.79−1.11). Univariate Kaplan-Meier analysis showed that severe CRF patients did not have significantly worse survival rates than those with mild-moderate CRF (p = 0.186). Conclusion Our findings indicated that severe CRF was not associated with all-cause mortality in patients receiving HD. Despite severe CRF being prevalent, larger cohort studies are needed to establish strong conclusions on its association with all-cause mortality.