Metabolic dysfunction-associated steatohepatitis (MASH) is a type of liver disease. It is characterized by an accumulation of excess fat in the liver, inflammation of the liver, and some amount of fibrosis, or scar tissue formation in the liver. It is formerly known as non-alcoholic steatohepatitis (NASH) and is an advanced form of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD).
Risk factors for MASLD and MASH
The exact causes of MASLD and MASH are not fully understood. This means that medical researchers do not have a definitive answer as to why some people develop these conditions and others do not.
The most frequent risk factor for MASLD (and by extension, MASH) is metabolic syndrome. A syndrome is a group of related health conditions that occur together. Metabolic syndrome is a group of related conditions caused by problems with metabolism (how the body uses and stores energy).
A person with metabolic syndrome will have three or more of these conditions:
- Overweight or obesity with excess adipose tissue around the waist
- Elevated blood glucose levels (high blood sugar) caused by insulin resistance
- High levels of triglycerides and LDL cholesterol
- Low levels of HDL cholesterol (HDL is known as the “good cholesterol” that protects against cardiovascular disease)
- High blood pressure (hypertension)
Genetics are also a risk factor for both metabolic disorder and MASLD. Having close family members with these conditions will increase a person’s risk of having these conditions. In addition to putting a person at risk for MASLD, metabolic syndrome increases a person’s risk of diabetes, cardiovascular disease, stroke, and kidney disease.
As the former name non-alcoholic fatty liver disease implies, a diagnosis of MASLD or MASH occurs in people with a history of low alcohol consumption.
How common is MASLD?
MASLD is a common condition, affecting over 30 percent of the world’s population. The prevalence has also increased by roughly 50 percent in the past three decades. The increase in the prevalence of MASLD coincides with the increasing prevalence of type 2 diabetes, obesity, and metabolic syndrome.
What are the complications of MASLD and MASH?
MASLD is a progressive condition that can become more severe, especially when left untreated. Mentioned at the beginning of this article, MASH is a more advanced form of MASLD. A person with MASH will be experiencing some amount of liver inflammation, liver damage, and liver scarring. MASH can progress to cirrhosis, extensive scarring that has changed the structure and function of the liver. This damage is not reversible, and it can lead to liver failure and liver cancer.
How is MASLD treated?
Treatment can help prevent MASLD and MASH from getting worse. Treatment decisions will depend on the person being treated, their overall health, coexisting health conditions, and how much the disease has progressed. Treatment goals will also be different depending on how much the disease has progressed.
In MASLD and the early stages of MASH, the main focus of treatment will be reducing weight and controlling blood glucose levels, cholesterol, and blood pressure. Diet and exercise to support liver health, cardiovascular health, and metabolic health will be a part of treatment. Treatment for any coexisting conditions or risk factors—like high cholesterol and blood pressure—will also be a part of treatment. Early-stage MASLD is reversable in some cases.
People with MASH who have moderate-to-advanced scarring in the liver may be treated with a medication that helps reduce fat accumulation and may help improve fibrosis. This medication cannot be used in people who have cirrhosis. This medication is intended to be used alongside changes to diet and exercise.
Treatment for cirrhosis focuses on slowing progression, easing symptoms, and managing complications. Liver transplantation may be recommended for suitable candidates.
MASLD and MASH affect different people in different ways. A healthcare provider will be your best source of information about diagnosis and treatment.
Sources: Cleveland Clinic. Metabolic Dysfunction-... + 20
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