Prevalence and risk factors for nonalcoholic fatty liver disease in the general population of northern Italy

ABSTRACT While there is increasing evidence that non-alcoholic fatty liver disease (NAFLD) may be the most common liver disease in Western countries, its prevalence and risk factors have not undergone a formal evaluation in a representative sample of the general population. We therefore performed a cross-sectional study in the town of Campogalliano (Modena, Italy), within the context of the Dionysos Project. Subjects with suspected liver disease (SLD), defined on the basis of elevated serum ALT and GGT activity, HBsAg or HCV-RNA positivity, were matched with randomly selected subjects of the same age and sex without SLD. A total of 311 subjects with and 287 without SLD underwent a detailed clinical, laboratory and anthropometrical evaluation. Fatty liver was diagnosed by ultrasonography and alcohol intake was assessed using a seven-day diary. Multinomial logistic regression was used to detect risk factors for normal liver vs. NAFLD and for alcoholic fatty liver (AFLD) vs. NAFLD. The prevalence of NAFLD was similar in subjects with and without SLD (25 vs. 20%, p = 0.203). At multivariable analysis, normal liver was more likely than NAFLD in older subjects and less likely in the presence of obesity, hyperglycemia, hyperinsulinemia, hypertriglyceridemia and systolic hypertension; AFLD was more likely than NAFLD in older subjects, males and in the presence of elevated GGT and hypertriglyceridemia and less likely in the presence of obesity and hyperglycemia. We conclude that NAFLD is highly prevalent in the general population, is not associated with SLD, but is associated with many features of the metabolic syndrome.