NAFLD is now MASLD: What’s New in 2023

Department of Medicine Grand Rounds, September 29, 2023
Presented by Rotonya M. Carr, MD, FACP
Associate Professor of Medicine
Cyrus E. Rubin Endowed Chair and Division Head
Division of Gastroenterology, Department of Medicine
University of Washington

[MrStarchild]

The video discusses the recent change in nomenclature from non-alcoholic fatty liver disease (NAFLD) to metabolic dysfunction associated steatotic liver disease (MASLD or "mazzled"). The main points are:

- The name change from NAFLD to MASLD resulted from a multi-year, multi-society consensus process involving professional societies, patient advocacy groups, and other stakeholders. This was not a rushed or arbitrary change.

- There were several factors driving the change, including history, societal pressures to destigmatize the condition, and an improved scientific understanding of the biology and pathogenesis of fatty liver disease.

- Historically, fatty liver conditions have been recognized since the 1800s, with terms like "fatty liver" and "non-alcoholic steatohepatitis" (NASH) emerging over time. The term NAFLD was coined in 1980. Recently, there has been more focus on updating the terminology to better reflect current knowledge.

- The term NAFLD was stigmatizing to patients - the inclusion of "fatty" and the reference to "alcohol" led to patient shame and discrimination, even for those without advanced disease. Patient advocacy groups pushed for a change to reduce stigma.

- Scientifically, there is now more evidence that the pathogenesis is driven by metabolic dysfunction and steatosis (fat accumulation), rather than inflammation. Genetic studies also point to steatosis being the key driver. This led to calls for a more biologically-accurate name.

- In 2020, some societies proposed changing the name to "metabolic dysfunction-associated fatty liver disease" (MAFLD). But this was controversial, as societies worldwide were not included in that process.

- In response, a formal Delphi consensus process was undertaken from 2020-2022 to re-examine the terminology. This involved societies from around the world, covering hepatology, endocrinology, pediatrics, and many other disciplines.

- The Delphi process considered many factors, including the potential impact on patients, clinical practice, trials, and drug development. Extensive discussion and debate occurred over 2 years.

- In June 2022, the new term MASLD was announced as the consensus recommendation, referring to “metabolic dysfunction associated steatotic liver disease”.

Key features of MASLD:

- It applies to all forms of fatty liver disease that are associated with metabolic dysfunction, after excluding other potential causes. This includes obesity, diabetes, hypertension, and lipid disorders.

- Specific diagnostic criteria are provided for both adults and children when defining “metabolic dysfunction”.

- The term “steatotic” focuses attention on fat accumulation as the key underlying pathology. This is based on an improved scientific understanding of how steatosis drives disease progression.

- Use of “metabolic dysfunction” also highlights the metabolic underpinnings versus a primary inflammatory disease.

- Alcohol-related liver disease and other specific forms of fatty liver retain their distinct names and are not called MASLD.

- For patients with both metabolic dysfunction and excess alcohol intake, the term “metabolic and alcohol-associated steatotic liver disease” (MALD) is used.

The goals of the new nomenclature include reducing stigma for patients, better reflecting current science, and providing an impetus for further research and education on fatty liver disease.

However, there are still challenges with the transition:

- The long name is cumbersome. Shorthand versions like “metabolic liver disease” may be needed for practical use.

- Despite attempts to reduce stigma, the words “fatty” and “steatotic” may still carry negative connotations in some sociocultural contexts.

- Updating medical coding, medical education, and clinical systems like Epic will take years. NAFLD will likely persist in documents and systems for some time.

- Measuring the impact on stigma will require further study. Surveys on patient perceptions should be repeated in the MASLD era.

In summary, the name change to MASLD was a deliberate, consultative process by the hepatology community to address the limitations of the prior NAFLD terminology. Work is now needed locally and globally to drive adoption of MASLD and assess its impact. Widespread use of the new nomenclature will likely take years. Patience and collaboration across specialties and systems will be required to ensure this major terminology change achieves its goals.