Serum Myostatin at Dialysis Initiation May Predict 1-Year Mortality and Hospitalization.

Objective: Myostatin, which is known as a negative skeleton muscle regulator, is associated with mortality in maintenance hemodialysis patients. However, the significance of serum myostatin concentrations at dialysis initiation has not been established. We investigated the relation between serum myostatin concentrations and mortality or hospitalization within 1 year in incident dialysis patients.

Methods: After a patient initiating hemodialysis or peritoneal dialysis during 2016-2018 was enrolled, the patient's serum myostatin at dialysis initiation was measured. Composite outcomes comprising mortality and hospitalization within 1 year after dialysis initiation were compared between two groups divided according to myostatin levels. The Cox proportional hazards model was used to assess significant relations between myostatin and outcomes.

Results: This study examined 104 incident dialysis patients with a mean age of 65.5 ± 14.0 years (68% male). Kaplan-Meier analyses indicated the 1-year hospitalization-free and survival rate as significantly lower in the lower myostatin group than in the higher myostatin group (p = 0.0020). Cox proportional hazards regression analyses revealed that the value of myostatin logarithm at dialysis initiation was inversely associated with the occurrence of a composite outcome, independently of age (hazard ratio 0.16, 95% confidence interval: 0.05-0.57). Receiver operating characteristic analysis showed the area under the curve of serum myostatin for predicting death or hospitalization within 1 year as higher than those of clinical indices of nutritional disturbance and frailty.

Conclusion: Serum myostatin concentration at dialysis initiation is inversely associated with adverse outcomes in these dialysis-initiated patients.