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Non-alcoholic Steatohepatitis (NASH)

Non-alcoholic steatohepatitis (NASH) can be defined as the liver manifestation of a metabolic disorder, and is the most severe form of non-alcoholic fatty liver disease (NAFLD). NASH is closely related to the triple epidemic of obesity, pre-diabetes, and diabetes. But its symptoms are often silent or non-specific to NASH, making it difficult to diagnose. As a result, NASH patients can remain unaware of their condition until late stages of the disease.

Who gets NASH?

Researchers are trying to understand why some people who have NAFLD develop NASH and others don’t. The condition may be hereditary. If a person has family members who have or had NASH or NAFLD, they are at risk. Additionally, having certain health conditions may increase a person’s risk to develop NASH. These include:

  • Being overweight or obese.
  • Having high cholesterol or high triglyceride levels.
  • Having type 2 diabetes, insulin resistance or prediabetes.

Incidence Rate

NAFLD is the most common chronic liver condition in the United States. It is estimated that about 25 percent of adults in the U.S. have NAFLD. Of those with NAFLD, about 20 percent have NASH (5% of adults in the U.S.). Most people with NAFLD have simply fatty liver. Due to the growing number of children with obesity, NASH is the most common cause of chronic liver disease in children between the ages of 2 and 19 in the United States.