From the Guidelines
The main difference between Methanol-Associated Steatohepatitis (MASH) and Non-Alcoholic Steatohepatitis (NASH) cirrhosis is primarily terminological rather than clinical, with MASH being the newer term that replaces NASH to reflect the metabolic nature of the disease. According to the most recent guidelines, MASH is characterized by histological features of hepatocellular ballooning and lobular inflammation, and is associated with an increased risk of cardiovascular events, chronic kidney disease, hepatic and extrahepatic malignancies, and liver-related outcomes, including liver failure and hepatocellular carcinoma (HCC) 1. The condition is strongly associated with metabolic dysfunction, obesity, type 2 diabetes, and insulin resistance.
Key Differences and Similarities
- Both MASH and NASH refer to the same liver disease characterized by fat accumulation, inflammation, and damage in the liver that is not caused by excessive alcohol consumption.
- The name change from NASH to MASH was made to emphasize the metabolic origins of the disease and remove the potentially stigmatizing "non-alcoholic" terminology, while the underlying disease process and management remain unchanged.
- Treatment approaches remain the same and focus on lifestyle modifications including weight loss, dietary changes, exercise, and managing underlying metabolic conditions.
- There are currently no FDA-approved medications specifically for MASH/NASH, though several are in clinical trials, such as resmetirom, which has demonstrated histological effectiveness on steatohepatitis and fibrosis with an acceptable safety and tolerability profile 1.
Management and Treatment
- Lifestyle modification, including weight loss, dietary changes, physical exercise, and discouraging alcohol consumption, as well as optimal management of comorbidities, is advised for adults with MASH/NASH 1.
- Bariatric surgery is also an option in individuals with MASH/NASH and obesity.
- Management of MASH-related cirrhosis includes adaptations of metabolic drugs, nutritional counselling, surveillance for portal hypertension and HCC, as well as liver transplantation in decompensated cirrhosis.
Overall, the management of MASH and NASH cirrhosis prioritizes lifestyle modifications, management of underlying metabolic conditions, and surveillance for complications, with the goal of improving morbidity, mortality, and quality of life outcomes 1.
From the Research
Definition and Causes
- Methanol-Associated Steatohepatitis (MASH) and Non-Alcoholic Steatohepatitis (NASH) are both forms of liver disease, but they have different causes.
- NASH is a progressive form of Nonalcoholic Fatty Liver Disease (NAFLD) that can lead to cirrhosis, hepatocellular carcinoma, and the need for liver transplantation 2.
- MASH, on the other hand, is also known as Metabolic Dysfunction-Associated Steatohepatitis, and it is associated with metabolic dysfunction, such as obesity, insulin resistance, and dyslipidemia 3.
Pathogenesis and Progression
- Both MASH and NASH can progress to cirrhosis, but the pathogenesis and progression of the two diseases may differ.
- NASH is characterized by hepatic steatosis, inflammation, and fibrosis, and it is often associated with other metabolic conditions, such as diabetes and cardiovascular disease 4.
- MASH is also characterized by hepatic steatosis, inflammation, and fibrosis, but it is more closely associated with metabolic dysfunction, and it may have a different natural history than NASH 3.
Treatment and Management
- The treatment and management of MASH and NASH cirrhosis may differ.
- For NASH, treatment may include lifestyle modification, such as weight loss and exercise, as well as pharmacotherapy with vitamin E and pioglitazone 2.
- For MASH, treatment may include lifestyle modification, as well as novel therapeutic agents, such as resmetirom, which has been approved for the treatment of non-cirrhotic MASH with stages 2 and 3 fibrosis 3.
- Weight loss, either through lifestyle modification or bariatric surgery, may also be beneficial for patients with MASH and NASH, as it can improve hepatic steatosis, steatohepatitis, and potentially hepatic fibrosis 5.
Diagnosis and Identification
- The diagnosis and identification of MASH and NASH cirrhosis may involve non-invasive tests, such as imaging studies and biomarkers, as well as liver biopsy 3.
- The identification of patients with MASH and NASH who are at risk of developing adverse outcomes, such as cirrhosis, hepatocellular carcinoma, or liver-related death, is critical for the management of these diseases 3.