[Metabolic dysfunction associated steatohepatitis, epidemiology and definitions: from steatosis to cirrhosis]

A recent change in terminology proposed by scientific societies replaces the term NAFLD (non-alcoholic fatty liver disease) with the term MASLD (metabolic dysfunction associated steatotic liver disease). The prevalence of metabolic steatosis in France is 18.2%, higher among at-risk individuals (obese, diabetic, or with elevated transaminases). Among patients with MASLD, approximately 25% have liver inflammation with hepatocyte damage, now referred to as MASH (Metabolic dysfunction Associated Steatohepatitis), replacing the former name NASH (Non Alcoholic Steatohepatitis). MASH is associated with a significant increase in overall mortality, related to the severity of histological lesions, particularly cirrhosis. Cirrhosis develops in 15% to 30% of patients with MASH, usually at an older age than in other chronic liver diseases, due to a slower progression rate of fibrosis. Closely related to metabolic syndrome and insulin resistance, the disease progression involves the liver (progression of fibrosis, development of cirrhosis) but also exposes individuals to a significant risk of extrahepatic complications, such as cardiovascular, metabolic, and neoplastic diseases.