Serum myostatin and irisin as predictive biomarkers of sarcopenia, malnutrition and mortality in patients with decompensated liver cirrhosis

Abstract

Malnutrition and sarcopenia are nowadays considered the main complications of liver cirrhosis (LC). Myokines are signal peptides synthesized in muscles that regulate muscle strength and mass and mediate crosstalk between skeletal muscles and other organs. It is unknown whether circulating myokines can be used as biomarkers of malnutrition and sarcopenia and have independent prognostic value in LC. The purpose of the study was to assess the relationship of serum levels of myokines myostatin and irisin with nutritional status, skeletal muscle status, and survival in decompensated LC patients. 74 patients (55.30±11.40 years) were involved in the prospective study. Nutritional status was assessed using the Patient-Generated Subjective Global Assessment, and skeletal muscle mass was assessed using the Skeletal Muscle Index. The concentration of serum myostatin and irisin was determined by enzyme immunoassay. Statistical data processing was performed in SPSS22 (© SPSS Inc.). It was established that the concentration of serum myostatin and irisin is not related to the LC severity according to the Child-Turcotte-Pugh, Model For End-Stage Liver Disease, and the grade of ascites. Patients with overt encephalopathy have higher myostatin levels. Patients with severe hypoalbuminemia have higher serum myostatin and lower serum irisin levels. The development of malnutrition and sarcopenia in decompensated LC patients is associated with increased serum myostatin concentration and decreased serum irisin concentration. Serum myostatin level can predict sarcopenia (AUC 0.834 in males and 0.827 in females, p<0.01). Serum irisin level can predict severe malnutrition (AUC 0.830, p<0.001). The mortality of patients with high myostatin levels (above 5.25 ng/ml in males and 3.55 ng/ml in females) and low irisin levels (less than 1.72 ng/ml) is significantly higher. In conclusion, the circulating myokines levels may be useful in the assessment of nutritional and skeletal muscle status, and prediction of mortality in LC patients.