Background and aim: Differences in the prevalence of non-alcoholic fatty liver disease (NAFLD) between Eastern and Western populations are primarily attributable to differences in definitions and biased population selection. Thus, the aim of the present study was to accurately determine the actual prevalence of NAFLD by sonography and to characterize the risk factors for NAFLD.
Methods: The present cross-sectional study was performed with data obtained from 6,648 subjects, all of whom were older than 20 years of age (3,530 men and 3,118 women). The term 'non-drinker' was applied to men who consumed less than 30 g alcohol/day and to women who consumed less than 20 g alcohol/day. Non-alcoholic fatty liver disease was defined as a sonographically detected fatty liver in the absence of viral hepatitis in a non-drinker.
Results: Of the 1,613 subjects who were diagnosed with sonographic fatty liver, 1,240 were non-drinkers and had no viral hepatitis. Overall, the unadjusted and age-adjusted prevalences of NAFLD were 18.7% (23% in men, 13.7% in women) and 16.1% (21.6% in men, 11.2% in women), respectively. Multivariate analysis revealed that several risk factors were profoundly associated with the prevalence of NAFLD, including obesity, insulin resistance, hyperlipidemia and hyperglycemia in both genders, as well as age, menopausal status and estrogen medication in women only.
Conclusions: These results demonstrate that the prevalence of NAFLD in Korean adults, according to sonographic surveys, is comparable to that seen in more developed countries. From the perspective of increasing obesity, the high prevalence rates noted in the study may herald an increased burden of chronic liver disease in the Korean population.