BEIJING, Jan. 7, 2022 /PRNewswire/ — Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Conventional diagnosis includes imaging or histological evidence of steatosis (accumulated liver fat) in >5% of hepatocytes, and the absence of known causes of chronic liver disease, like alcohol abuse, viral hepatitis, hereditary liver diseases, or long-term usage of steatogenic medications. The dramatic increase in the prevalence of NAFLD in recent years and its diverse clinical presentations necessitate clearer disease definition and diagnostic criteria.
A group of international experts in hepatic pathology has recently arrived at a consensus to redefine NAFLD to metabolic (dysfunction)-associated fatty liver disease (MAFLD). This newly proposed concept includes evidence of hepatic steatosis along with either obesity, type 2 diabetes mellitus (T2DM), or metabolic dysregulation. In a review article first published online on 14 December 2020 in Chinese Medical Journal, Prof. Fen Xu of The Third Affiliated Hospital of Sun Yat-Sen University, China, and his colleagues explore the similarities and differences of NAFLD and MAFLD, with particular emphasis on epidemiology, pathophysiology, diagnosis, and pharmacotherapy. "This new definition focuses on the importance of metabolic dysfunction in fatty liver disease," remarks Prof. Xu.
Notably, a quarter of the world’s population meets the criteria for NAFLD diagnosis, those with T2DM or obesity having a higher likelihood. Given that MAFLD places additional emphasis on metabolic dysfunction and includes alcohol intake, the researchers speculate that the new definition will lead to increased prevalence estimates. Furthermore, the rising prevalence of obesity and T2DM will likely lead to rapid escalation in MAFLD prevalence. The new definition will help guide future investigations by distinguishing epidemiological features and mechanisms that distinguish MAFLD from NAFLD.
Early detection of MAFLD will, in turn, serve to encourage timely initiation of interventions to minimize health impacts. Furthermore, the correlation between T2DM, obesity, and MAFLD suggests that anti-obesity and anti-hyperglycemic drugs could be effective in improving liver histology and clinical outcomes in patients with MAFLD. Also, drugs that are effective in preventing cardiovascular disease in patients with T2DM may reduce the risk of cardiovascular mortality in patients with MAFLD. However, clinical trials will be necessary to confirm the utilities of such drugs in patients with MAFLD.
A classification shift from NAFLD to MAFLD will have important consequences, including a more direct and explicitly acknowledged relationship with other morbidities like obesity and T2DM. "There is a compelling need to clarify the epidemiological features and mechanisms that drive the development and progression of MAFLD. This can greatly aid the implementation of programs for early diagnosis and treatment," concludes Prof. Xu.
Title of original paper: MAFLD vs. NAFLD: shared features and potential changes in epidemiology, pathophysiology, diagnosis, and pharmacotherapy
Journal: Chinese Medical Journal
SOURCE Chinese Medical Journal