FP418SARCOPENIA, MUSCLE MASS AND PLASMA MYOSTATIN AFTER 12 MONTHS OF EXERCISE TRAINING IN PATIENTS WITH CKD: A SUB-STUDY OF RENEXC –A RANDOMIZED CONTROLLED TRIAL

Abstract

INTRODUCTION: Background: Sarcopenia is common in chronic kidney disease (CKD) and associated with greater risk of morbidity and mortality. Myostatin is a negative regulator of muscle growth. Its relationship to muscle mass and expression in response to exercise is unclear. We aimed to investigate (1) the effects of 12 months of exercise training, comprising endurance training in combination with either strengthor balance‐ training, in non‐dialysis dependent patients with CKD stages 3 to 5, on sarcopenia, muscle mass and plasma myostatin, (2) relationships between physical performance, muscle mass and plasma myostatin. METHODS: Methods: 151 adult patients with eGFR (estimated GFR) < 30ml/min/ 1.72m2, not on renal replacement therapy, irrespective of comorbidities were randomly assigned to either strength‐ or balance training in combination with endurance training. Both groups were prescribed 150 minutes per week of selfadministered exercise training for an intervention period of 12 months. Body composition was measured with dual‐energy X‐ray absorptiometry. Plasma myostatin was analyzed using ELISA kits. Paired t‐test was used to compare parametric variables, and paired Wilcoxon test was used to compare nonparametric variables. Linear regression analysis was used to analyze the relationships between variables. A p‐value <0.05 was considered statistically significant. Data were analyzed using the R‐software (R foundation for Statistical Computing, Vienna, Austria). RESULTS: 112 patients completed 12months of exercise training, and these completers were included in this sub‐study. After 12months, the prevalence of sarcopenia was unchanged, leg‐ and whole body leanmass increased significantly in the balance group, but not in the strength group.Whole fatmass decreased significantly in both groups. There were no significant differences between groups for changes in physical performance, sarcopenia or body composition. Plasma myostatin levels increased significantly in both groups,with a significant difference in favor of the strength group. Plasmamyostatin was significantly positively related tomusclemass and physical performance at baseline, but these relationships were attenuated after 12 months. CONCLUSIONS: Conclusions: These findings indicate that exercise training could be effective in preventing sarcopenia and maintaining muscle mass, and that plasma myostatin is not a robust marker for muscle mass or physical performance in patients with CKD.