Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) is associated with insulin resistance and considered as a liver manifestation of metabolic syndrome. Triglycerides and glucose (TyG) index is a useful marker of insulin resistance but there are few studies about association between TyG index and NAFLD/NASH. The aim of this study was to investigate the ability of TyG index to identify NAFLD/NASH through comparing with fatty liver index (FLI) in a Korean population using a large health study database. We enrolled 187,725 subjects (107,246 men and 80,479 women) in the Kangbuk Samsung Health Study cohort. All subjects were completed a comprehensive annual or biennial health examination from 2007 through 2013. The presence of NAFLD was ascertained by ultrasonography in the absence of other known liver diseases. NASH was defined as NAFLD with FIB-4 index > 1.3. Mean age was 37 years and mean body mass index (BMI) was 23.26 m/kg2. The prevalences of NAFLD and NASH were 35.66% (n = 66,946) and 3.06% (n = 5,749), respectively. During a median 3.92-year follow-up, the hazard ratios (HR) of TyG index and FLI for NAFLD were 1.772 (95% CI 1.747-1.798) and 1.424 (95% CI 1.411-1.438), respectively. After adjusting for age, sex, and BMI, there were still elevated HRs for NAFLD (TyG index: 1.322, 95% CI 1.301-1.344; FLI: 1.094, 95% CI 1.073-1.116). The area under the ROC curve for identifying NAFLD of TyG index and FLI were 0.799 and 0.873, respectively. In non-obese subjects (BMI < 23 kg/m2), higher TyG index was associated with an increased risk of NASH (HR 1.222; 95% CI 1.095-1.363) but FLI was not (HR 1.056; 95% CI 0.922-1.209). In addition, there were similar results in obese subject (TyG index: 1.085, 95% CI 1.046-1.126; FLI: 0.994, 95% CI 0.942-1.049). These results suggested that TyG index was superior to FLI in association with NAFLD/NASH risk. The TyG index is effective to identify subjects at risk for NAFLD/NASH.


K. Kim: None. Y. Hwang: None. H. Ahn: None. S. Park: None. C. Park: None.

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