Understanding Lean NASH: Fatty Liver Disease in Non-Obese Patients

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• Lean NAFLD Overview
• Ethnic Prevalence Factors
• Lean NASH Explained
• BMI and Risk Assessment
• Diabetes and Progression Risk
• Full Transcript

Lean NAFLD Overview

Non-alcoholic fatty liver disease (NAFLD) is most commonly associated with obesity and metabolic syndrome. However, Dr. Scott Friedman, MD, clarifies that NAFLD is not exclusive to obese individuals. He confirms that lean, non-obese patients can also develop this serious liver condition.

Ethnic Prevalence Factors

Dr. Scott Friedman, MD, identifies specific ethnic groups with a higher prevalence of lean NAFLD. He notes a greater occurrence among Asian populations, including both South Asians and individuals from the Far East. Dr. Scott Friedman, MD, attributes this increased risk partly to unknown factors, with genetic influences being a strong presumptive cause.

Lean NASH Explained

The condition known as 'Lean NASH' is a distinct clinical entity. Dr. Friedman describes it as a state where patients are not obese yet exhibit all the hallmark features of nonalcoholic steatohepatitis. These patients face significant health challenges despite their normal body weight.

BMI and Risk Assessment

Body mass index (BMI) alone is not a definitive predictor of NASH risk, according to Dr. Scott Friedman, MD. He explains that while BMI measures obesity, it does not directly correlate with liver disease severity in isolation. The risk becomes substantially elevated only when BMI is coupled with other metabolic comorbidities.

Diabetes and Progression Risk

Type 2 diabetes emerges as a critical factor in NAFLD progression. Dr. Scott Friedman, MD, emphasizes that diabetic patients with NAFLD face a dramatically heightened risk of developing NASH. This combination significantly accelerates the progression to advanced liver fibrosis and ultimately cirrhosis, making diabetes management crucial in these patients. Dr. Anton Titov, MD, facilitates this important discussion on liver health.

Full Transcript

Dr. Scott Friedman, MD: So NAFLD happens as part of the metabolic syndrome, and most patients are obese. Can non-alcoholic fatty liver disease happen in lean, non-obese patients? Yes, it can.

That's an important point, Anton. There is a subset that seems to be of higher prevalence among different ethnicities, for example, among Asians, both South Asians and those from the Far East, for reasons we don't know, but presumably in part because of genetic factors.

There is the possibility of so-called Lean NASH, where the patient is not obese, and yet they still have the features of NASH. Those patients are at equal risk of NASH.

It's not clear that the body mass index, which is a measure of obesity, is by itself a major risk factor, except when it is associated with other comorbidities, in particular type two diabetes.

The presence of type two diabetes in patients, particularly those who are obese, but especially those with NAFLD and diabetes, confers a heightened risk of developing NASH and progressing to fibrosis and cirrhosis.