Bioelectrical impedance analysis (BIA) is a body composition assessment method. We aimed to determine its accuracy in the detection of sarcopenia in patients with liver cirrhosis (LC), using skeletal muscle index (SMI) at the level of third lumbar vertebra (L3-SMI) obtained using multislice computed tomography as the reference method. Patients with LC were enrolled in the period October 2019–March 2022 and follow-ups were conducted until January 2023. Their BIA parameters were compared against L3-SMI, and BIA cut-off values were proposed using AUROC analysis. Patients underwent outcome analysis based on obtained clinical characteristics. A total of 106 patients were included. We found a fair correlation between BIA parameters with the L3-SMI. We determined cut-off values of ≤11.1 kg/m² for BIA-SMI (Se 73%, Sp 66%, AUROC 0.737, p < 0.001) and ≤5.05° for phase angle (PA) (Se 79%, Sp 60%, AUROC 0.762, p < 0.001) in the detection of sarcopenia. The relative risk of death was 2.2 times higher in patients with skeletal muscle mass (SMM) ≤ 36.5 kg. SMM was significantly associated with outcome in Kaplan–Meier analysis. This non-invasive and simple method that showed fair performances and a very good outcome prediction could provide for the unmet need for fast and affordable detection of sarcopenia in patients with LC and should be further evaluated.

Sarcopenia refers to a disorder involving the gradual and overall reduction in skeletal muscle mass and physical capability. It occurs in over one-third of individuals with liver cirrhosis and serves as an independent predictor of increased mortality risk. Assessment of sarcopenia is necessary in all patients with liver cirrhosis, as recommended by the European Association for the Study of the Liver (EASL) and the European Society for Clinical Nutrition and Metabolism (ESPEN). The evaluation of muscle mass can be performed using several validated methods such as the multislice computed tomography (MSCT), abdominal magnetic resonance imaging (MRI), dual X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), or muscle ultrasound. Assessment of muscle function encompasses measurements of both muscle strength and physical performance. Sarcopenia has a significant negative impact on the course of the disease, quality of life and outcomes of patients with liver cirrhosis. Considering the global healthcare impact and the significant influence on the course of disease, characteristics of simplicity, swiftness, safety, availability, reproducibility, and diagnostic accuracy are certainly the key factors to consider when choosing the proper diagnostic method for nutritional assessment. The aim of this review is to analyze the pathophysiological mechanisms underlying muscle mass loss in patients with liver cirrhosis, as well as to assess strengths and limitations of the methods currently in use to diagnose sarcopenia.