Background: We evaluated the frequency of non-alcoholic fatty liver diseases, and the associations between the metabolic abnormalities and severity of non-alcoholic fatty liver disease in Korean adults using ultrasonography.
Methods: We examined 1074 Korean adults above the age of 30 years, comprising of 502 men and 572 women, participating in medical check-ups at the Health Promotion Center. Hepatitis B and C serologies were negative, and the average weekly alcohol intake was ≤ 2 standard drinks. A standard interview, physical exam and biochemical study, were conducted, and an experienced operator carried out ultrasound liver studies.
Results: 522 of the subjects had non-alcoholic fatty liver disease, and the remaining 552 did not. The frequency in the men was higher than that in the women (57 vs 42%, p<0.05). The frequency of non-alcoholic fatty liver disease in the subjects without diabetes, obesity or dyslipidemia was 20%. We classified subjects into 4 groups: the controls(n=552) and those with mild(n=218), moderate(n=273) or severe fatty liver disease(n=31), according to their ultrasonographic findings. BMI, waist circumference, body fat, systolic blood pressure, aspartate aminotransferase, alanine aminotransferase, total cholesterol, triglyceride, the total- to HDL-cholesterol ratio, impaired fasting glucose, hypertension and insulin resistance, were all significantly increased with the increased severity of non-alcoholic fatty liver disease(p<0.05). Following the multiple regression analyses, waist, alanin aminotransferase, HOMAIR, the total- to HDL-cholesterol ratio, aspartate aminotrans- ferase and systolic blood pressure, were all associated with the severity of non-alcoholic fatty liver disease. Odd ratios of insulin resistance in the mild, moderate and severe non-alcoholic fatty liver disease were 14.7(CI: 6.8~32.0), 6.9(CI: 4.6~10.3) and 5.7(CI3.6~8.8), respectively. The percentages of subjects with insulin resistance in each group were 7.6, 32.0, 36.0 and 55.0%(p<0.05), respectively. The percentages of subjects with risk of non-alcoholic steatohepatitis in each groups were 5.0, 21.6, 27.8 and 58.1%(p<0.05) respectively.
Conclusion: The frequency of non-alcoholic fatty liver disease was relatively high in Korean adults. Proportional differences in metabolic abnormalities, relation to the severity of non-alcoholic fatty liver disease, were found by ultrasonography