The Relationship Between Nonalcoholic Fatty Liver Disease And Metabolic Syndrome

Background and aims:With the development of economy, there has been an increasing prevalence of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) in China. NAFLD is recognized as the hepatic manifestation of MS, with insulin resistance as the key pathogenetic mechanism. The aim of this study was to investigate the prevalence of NAFLD and MS in patients who underwent the routine health checkups. We intended to establish a clinical association between NAFLD and MS as well as compare the diagnostic criteria of MS based on the definitions set forth by the International Diabetes Federation (IDF), the US National Cholesterol Education Program Adult Treatment PanelⅢ(2001) (NCEP ATP-Ⅲ) and the Metabolic Syndrome Study Group of the Chinese Diabetes Society (CDS).Patients and methods:Weight, height, waist circumference, hip circumference, percentage of body fat, blood pressure and ultrasound of the liver were performed on patients undergoing routine health screenings. Serum triglyceride, total cholesterol, high density lipoprotein cholesterol and fasting glucose level were measured. The prevalence of NAFLD and MS among these subjects was determined. The prevalence of MS were compared using diagnostic criteria established by IDF, NCEP ATP-Ⅲand CDS. The relationship between NAFLD and MS was assessed by analyzing the prevalence rates in each subgroup.Results:2394 people (1063 men and 1331 women, mean age 41.40±15.29 and 42.01±17.17) were included in the analysis. In this sample,437 (18.25%) had NAFLD and among them,284 (64.99%) patients had a BMI≥25 kg/m2 and 153 patients (35.01%) had a BMI< 25 kg/m2.The prevalence of MS in the total sample according to the IDF, NCEP ATP-Ⅲand CDS definitions were 11.11%(266/2394),8.48%(203/2394) and 5.30%(127/2394) respectively. The degree of agreement between IDF and NCEP ATP-Ⅲ, CDS and NCEP ATP-Ⅲ, CDS and IDF were 91.52%,93.32% and 90.69%, respectively. The prevalence of MS, according to the IDF, NCEP ATP-Ⅲand CDS definitions, among the 437 NAFLD and 1957 non-NAFLD subjects were 36.84% (161/437)& 5.37%(105/1957),26.09%(114/437)& 4.55%(89/1957) and 20.37% (89/437)& 1.94%(38/1957), respectively. The prevalence of NAFLD among the MS patients and non-MS subjects according to the IDF, NCEP ATP-Ⅲand CDS definitions were 62.78%(161/266)& 12.97%(276/2128),56.16%(114/203) & 14.74%(323/2191) and 70.08%(89/127)& 15.35%(348/2267), respectively.Conclusions:The prevalence of MS varied depending on the diagnostic criteria used. NAFLD was strongly associated with the MS, although it remains unknown whether NAFLD is a cause or effect of MS.