Fatty liver disease index: a simple screening tool to facilitate diagnosis of nonalcoholic fatty liver disease in the Chinese population.

BACKGROUND AND OBJECTIVES: A simple screening tool is needed as an aid to optimize management of nonalcoholic fatty liver disease (NAFLD). The purpose of this study was to design a simple index that could be used to predict the presence of NAFLD. METHODS: A cross-sectional case-control study design was used for this study with 6,926 subjects who had received health assessments. RESULTS: Multivariate analysis indicated that body mass index (BMI), triglyceride (TG), alanine aminotransferase (ALT) to aspartate aminotransferase (AST) ratio (ALT/AST ratio), and hyperglycemia (HG) were independent risk factors for NAFLD. These variables were used to construct a fatty liver disease (FLD) index: FLD index = BMI + TG + 3 × (ALT/AST ratio) + 2 × HG (presence of HG, HG = 1; absence of HG, HG = 0). The FLD index had an area under the receiver-operating characteristic (AUROC) curve of 0.819 in the training set and 0.817 in the validation set. Values of the FLD index <28.0 or >37.0 excluded the possibility of NAFLD with sensitivity of 94.9 % or detected NAFLD with specificity of 96.0 %, respectively. CONCLUSIONS: The FLD index is a simple, efficient NAFLD screening tool for the Chinese population that may be used to select people for further analysis and/or treatment, and/or for lifestyle modification.