Comment:
The term metabolic dysfunction-associated fatty liver disease (MAFLD) has recently been
suggested as an alternative to non-alcoholic fatty liver disease (NAFLD). Unlike NAFLD,
MAFLD’s diagnosis is based on the active identification of NAFLD-associated metabolic abnormalities. Many researchers agree that MAFLD adequately captures the systemic factors and upstream drivers of the disease, with a significant proportion concluding that it does so better than the original NAFLD definition. However, limitations of the term and concerns regarding the premature transition from NAFLD to MAFLD have also been expressed.
This article is a response to criticism of the authors’ initial study, which compared the difference between NAFLD and MAFLD in patients with type 2 diabetes mellitus (T2DM). It concluded that prematurely transitioning from NAFLD to MAFLD led to an over-diagnosis of fatty liver, exaggerated mortality, and morbidity in patients with T2DM.
As such, this response aims to reiterate and justify the results of the authors’ initial article.
Key learnings:
The use of the term MAFLD as an overarching diagnostic category may obscure the contribution of multiple aetiologies to liver disease. As such, grouping these aetiologies under MAFLD instead of considering them individually may increase the risk of misdiagnosis. This may significantly impact patients, as overlooked causes of liver disease may require vastly different management strategies. Thus, patients may not receive the treatments they need.
Furthermore, while the MAFLD definition may increase the sensitivity of determining all-cause outcomes, this does not mean that its prognostic utility is reliable. The use of MAFLD may simultaneously reduce the specificity of attributing these all-cause outcomes to fatty liver disease.
Ultimately, while MAFLD’s strengths remain undisputed, its weaknesses are equally as important to consider. Before these limitations are acknowledged and addressed, consensus regarding the transition from NAFLD to MAFLD will not be fully achieved.