The epidemiology of nonalcoholic fatty liver disease in adults.

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease that has been shown to progress to cirrhosis and hepatocellular carcinoma. This article reviews the prevalence of NAFLD and the factors associated this disorder, and with the more advanced stages of NAFLD, including nonalcoholic steatohepatitis (NASH) and fibrosis. In the general population, the estimated prevalence ranges from 3% to 24%, with most estimates in the 6% to 14% range. NAFLD is extremely common among patients undergoing bariatric surgery, ranging from 84% to 96%. In these patients, 25% to 55% have NASH, 34% to 47% have fibrosis, and 2% to 12% have bridging fibrosis or cirrhosis. NAFLD appears to be most strongly associated with…