ASMBS Position Statement on the Impact of Metabolic and Bariatric Surgery on Nonalcoholic Steatohepatitis

The following position statement is issued by the American Society for Metabolic and Bariatric Surgery in response to inquiries made to the Society by patients, physicians, society members, hospitals, health insurance payors, the media, and others regarding the impact of metabolic and bariatric surgery (MBS) on nonalcoholic fatty liver disease (NAFLD), specifically for laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG). The general principles described here may also apply to other procedures; however, the paucity of procedure-specific literature limits the value of this statement beyond these procedures. Additionally, this statement will mainly focus on , nonalcoholic steatohepatitis (NASH), which is the more severe presentation of NAFLD, strongly associated with type 2 diabetes (T2D), that can lead to fibrosis, cirrhosis, end-stage liver disease, and hepatocellular carcinoma [ [1] Sheka A. Adeyi O. Thompson J. Hameed B. Crawford P. Ikramuddin S. Nonalcoholic steatohepatitis: a review. JAMA. 2020; 323: 1175-1183 Google Scholar , [2] Adams L.A. Lymp J.F. St Sauver J. et al. The natural history of nonalcoholic fatty liver disease: a population-based cohort study. Gastroenterology. 2005; 129: 113-121 Google Scholar ]. Children and adolescents with obesity undergoing MBS may have unique considerations and are not specifically addressed in this position statement. This statement and its recommendations are based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence available at this time. The statement is not intended and should not be taken as a local, regional, or national standard of care. The statement will be revised in the future as additional evidence become available.