Protein and Macronutrient Metabolism in Liver Cirrhosis: About Sarcopenia.

Malnutrition, sarcopenia, and frailty are highly prevalent in patients with chronic liver disease and are closely associated with poor clinical outcomes. This review highlights the complex interplay between macronutrient metabolism and muscle wasting in liver cirrhosis. We explore the alterations in glucose, lipid, and amino acid metabolism that occur in cirrhosis, including the role of skeletal muscle in compensatory ammonia detoxification. The review also discusses the emerging evidence on sarcopenia as a prognostic marker and therapeutic target, with a focus on the role of branched-chain amino acid (BCAA) supplementation. While several studies have demonstrated the clinical benefits of BCAA in improving muscle mass, hepatic encephalopathy, and quality of life, results remain mixed, emphasizing the need for further well-designed clinical trials. Understanding the muscle-liver-gut axis may offer novel insights into therapeutic strategies for managing sarcopenia in liver disease.