Gut Dysbiosis, Malnutrition and Sarcopenia in Liver Cirrhosis: A Narrative Review

Liver cirrhosis represents the end stage of chronic liver disease arising from diverse etiologies and is characterized by persistent hepatic injury, architectural distortion, extensive fibrosis, and nodular regeneration. While decompensated cirrhosis is commonly associated with overt, life-threatening complications such as hepatic encephalopathy, hepatorenal syndrome and gastrointestinal bleeding, less apparent manifestations-including sarcopenia and metabolic disturbances-have emerged as major determinants of prognosis. Sarcopenia, defined by the progressive loss of skeletal muscle mass and function, is highly prevalent in cirrhotic patients and is closely linked to frailty, increased morbidity, mortality, and adverse liver transplantation outcomes. Increasing data support the role of gastrointestinal dysfunction in the pathogenesis of sarcopenia in liver cirrhosis. In chronic liver disease, intestinal dysfunction is exacerbated by portal hypertension, which promotes increased intestinal permeability and bacterial translocation. Furthermore, gut dysbiosis, a key feature of advanced liver disease, contributes to impaired digestion, malabsorption of macro- and micronutrients, increased intestinal permeability, malnutrition and systemic inflammation. These alterations promote negative energy balance, reduce muscle protein synthesis and enhance muscle catabolism, thereby accelerating muscle wasting. Despite increasing recognition of the individual roles of gut dysbiosis, malabsorption, and sarcopenia in cirrhosis, their complex interrelationship has not been comprehensively addressed. This narrative review synthesizes current evidence on the interplay between gut dysbiosis, malabsorption and sarcopenia in patients with liver cirrhosis. We discuss underlying pathophysiological mechanisms, clinical implications and potential therapeutic strategies, while highlighting existing knowledge gaps and future research directions. Improved understanding of the gut-liver-muscle axis may offer novel opportunities for early intervention and optimization of outcomes in this high-risk patient population.