Implications of the new nomenclature of steatotic liver disease and definition of metabolic dysfunction-associated steatotic liver disease

BackgroundThe American and European liver associations have endorsed new nomenclature of steatotic liver disease (SLD) and definition of metabolic dysfunction-associated steatotic liver disease (MASLD).AimsTo review the historical development leading to the changes and to discuss the implications of the changes on research and clinical practiceMethodsWe performed a literature search using keywords related to MASLD and non-alcoholic fatty liver disease (NAFLD).ResultsThe SLD umbrella allows classification of patients under the key categories of MASLD, alcohol-associated liver disease and a new entity termed MetALD, which represents MASLD with increased alcohol intake. The diagnosis of MASLD requires the demonstration of hepatic steatosis and at least one metabolic risk factor, whereas MASLD can co-exist with other liver diseases such as chronic viral hepatitis. Despite the change in definition, over 95% of patients previously known as having NAFLD fulfil diagnostic criteria for MASLD. It is conceivable that future clinical trials and biomarker studies will continue to exclude concomitant liver diseases. As most patients with MASLD are seen at primary care and non-hepatology settings, communication with other stakeholders is essential to ensure disease awareness and smooth adoption of the changes.ConclusionsThe new nomenclature is both a challenge, given the need for dissemination and education across the spectrum of stakeholders, and an opportunity to bring everyone together and spark new research to better understand epidemiology, natural history, diagnosis, biomarkers and management strategies across the spectrum of SLD. The American and European liver associations have endorsed new nomenclature of steatotic liver disease and definition of metabolic dysfunction-associated steatotic liver disease. The definition recognises the spectrum of disease due to metabolic risk factors, alcohol consumption, or both. This review article discusses the historical development leading to the changes and the implications of the changes on research and clinical practice.image