MASLD, MAFLD, or NAFLD criteria: have we re-created the confusion and acrimony surrounding metabolic syndrome?

Abstract

In 1980, there was the first description of patients with nonalcoholic steatohepatitis (NASH), most of whom were overweight and had type 2 diabetes. In the following years, there has been a growing appreciation that metabolic dysfunction underpins this liver disease, and metabolic dysfunction also contributes to the increased risk of extrahepatic complications, manifest in nonalcoholic fatty liver disease (NAFLD) as a multisystem disease. In 2020 & 2023, it was proposed that NAFLD should be renamed and reclassified as metabolic dysfunction-associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD), respectively. Despite subtle differences between MAFLD and MASLD, there is excellent congruence between NAFLD, MAFLD, and MASLD definitions, and affected patients usually meet the criteria for all. The following is a perspective of the authors’ views as to the challenges and advantages of the new fatty liver disease terminology and classification.