Association of the triglyceride-glucose index with the occurrence of non-alcoholic fatty liver disease and mortality in elderly inpatients: a prospective observational study.

Introduction: non-alcoholic fatty liver disease (NAFLD) is a disease in which there is excessive fat deposition in hepatocytes due to hepatoprotective factors. Objectives: to assess the association of the triglyceride-glucose index with the occurrence of non-alcoholic fatty liver disease and mortality in elderly inpatients. To identify the TyG index as a predictive factor of NAFLD. Methods: this prospective observational study included elderly inpatients admitted to the Department of Endocrinology at the Linyi Geriatrics Hospital, Affiliated to Shandong Medical College, between August 2020 and April 2021. The TyG index was calculated according to an established formula: TyG = Ln [triglycerides (TG) (mg/dl) × Fasting plasma glucose (FPG) (mg/dl) / 2]. Result: a total of 264 patients were enrolled, with 52 (19.7 %) cases occurred NAFLD. Multivariate logistic regression analysis showed that TyG (OR = 3.889; 95 % CI: 1.134-11.420; p = 0.014) and ALT (OR = 1.064; 95 % CI: 1.012-1.118; p = 0.015) were independently associated with the occurrence of NAFLD. Furthermore, receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of TyG was 0.727, with sensitivity = 80.4 % and specificity = 57.8 % at cut off = 8.71. A Cox proportional hazards regression model showed that, after adjusting for age, sex, smoking, drinking, hypertension, and type 2 diabetes, TyG > 8.71 (HR = 3.191; 95 % CI: 1.347 to 7.560; p < 0.001) was an independent risk factor for mortality in the elderly. Conclusions: the TyG index can predict non-alcoholic fatty liver disease and mortality in elderly Chinese inpatients.