MASLD epidemiology, natural history and diagnosis

Abstract

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the leading cause of chronic liver disease worldwide, with an estimated prevalence of 38%. Its burden varies considerably across regions, populations and demographic groups, influenced by genetic, biological, environmental and social factors. The disease follows a progressive histopathological continuum ranging from simple steatosis, through steatohepatitis, advanced fibrosis and cirrhosis, to hepatocellular carcinoma. The stage of fibrosis is the most important determinant of liver-related outcomes, while extrahepatic manifestations, particularly cardiovascular disease, represent the leading cause of mortality. For diagnosis, the focus has shifted from liver biopsy to non-invasive strategies that combine serum markers and imaging studies. These tools have already been incorporated into international clinical guidelines, although access to them remains uneven across different healthcare settings. This review aims to provide an updated and comprehensive overview of the epidemiology, natural history, and diagnostic strategies for MASLD, with an emphasis on recent epidemiological data, factors influencing disease progression, and the increasingly important role of non-invasive diagnostic tools in clinical practice.