LA JOLLA, CALIF. — The estimated prevalence of nonalcoholic fatty liver disease in the United States is 10%-33%, and is likely to climb even higher unless Americans start to lose weight.
“Our high body mass index is the main driving force of nonalcoholic fatty liver disease [NAFLD],” Dr. Paul J. Pockros said at a meeting on chronic liver disease sponsored by Scripps Clinic. “The reason we're in trouble is that too many people are eating 2,500 calories at each meal and are not exercising.”
The presence of metabolic syndrome or its manifestations can be associated with nonalcoholic steatohepatitis (NASH). In a study of 212 morbidly obese patients who underwent bariatric surgery, 93% had NAFLD, 26% had NASH, and 9% had advanced fibrosis at the time of their surgery (Obes. Surg. 2005;15:310-5). Independent predictors of NASH were high aspartate aminotransferase (AST) level, diabetes, and male sex. Independent predictors of advanced fibrosis were high AST, central obesity, and hepatocyte necrosis, said Dr. Pockros, head of the division of gastroenterology and hepatology at Scripps Clinic, La Jolla.
Another study found that patients with NAFLD plus diabetes had higher rates of cirrhosis than did patients who had NAFLD alone (25% vs. 10%, respectively). Overall mortality (risk ratio of 3.3) and mortality related to liver disease (risk ratio of 22.83) were greater in diabetic patients with NAFLD (Clin. Gastroenterol. Hepatol. 2004;2:262-5).
Dr. Pockros prescribes a low-fat, Mediterranean-type diet and exercise for his obese patients with NAFLD and NASH. “No single intervention has convincingly improved all important outcomes in NAFLD,” he said. “Our best approach is with diet and exercise.”
Dr. Pockros said he has received research support from, and is an adviser to, Roche, Vertex, and Gilead, and is an adviser to Amgen.