The study was carried out on the basis of the Department of Nephrology and Dialysis, Faculty of Postgraduate Education, Pavlov University, St. Petersburg, Russia
Objective. Evaluation of the relationship between serum myostatin levels and indicators of protein-energy malnutrition (PEM) in patients on program hemodialysis (PHD).
Material and methods. 645 patients on program HD were examined, among them 300 men and 345 women aged 56.8±12.8 years. All patients received treatment with program HD for 8.4±5.3 years. Assessment of nutritional status for the purpose of diagnosing PEM was carried out using the method proposed by ISRNM (International Society of Renal Nutrition and Metabolism). The blood serum myostatin level was determined by a method based on the principle of competitive enzyme immunoassay using mono- and polyclonal antibodies to myostatin using a commercial kit “Myostatin ELISA” (Immunodiagnostik, Germany) in accordance with the manufacturer’s instructions. Reference values for myostatin were 11–44 ng/ml.
Results. The prevalence of PEM, determined by the ISRNM method, was 24.9% (160 patients). The mean myostatin values in patients without signs of PEM were 31.2±16.2 ng/ml, and in patients with PEM – 76.7±25.5 ng/ml (P<0.0001). Patients with elevated myostatin levels had statistically significantly lower values of PEM indicators (body mass index, skeletal muscle mass index, as well as total protein, albumin, prealbumin, total cholesterol, transferrin and the number of blood lymphocytes) than patients with normal myostatin levels. At the same time, no statistically significant changes in body fat mass parameters depending on the myostatin level were detected. During the study, no significant relationship was found between the adequacy of the HD dose (spKt/V) and myostatin levels, which is confirmed, in particular, by the value of the Spearman correlation coefficient (Rs = 0.063; P = 0.106). In addition, there was no connection between the myostatin level and the duration of HD (Rs = 0.056; P = 0.151).
Conclusion. The prevalence of PEM, determined by the ISRNM method, in patients on program HD was 24.9%. An increase in the blood serum myostatin level may be an important pathogenetic link in the development of PEM in patients on program HD, mainly due to a negative effect on the patient’s muscle tissue.

Keywords: protein-energy deficiency, muscle tissue, myostatin, program hemodialysis