Association between triglyceride glucose-body mass index and non-alcoholic fatty liver disease in the non-obese Chinese population with normal blood lipid levels: a secondary analysis based on a prospective cohort study

Abstract

Background Both triglyceride glucose-body mass index (TyG-BMI) and non-alcoholic fatty liver disease (NAFLD) are linked to insulin resistance (IR). Prospective studies linking TyG-BMI to NAFLD have been limited by short follow-up. This study investigated the longitudinal association between TyG-BMI and NAFLD occurrence in the non-obese Chinese individuals. Methods This study determined TyG-BMI at baseline and the incidence of NAFLD at follow-up and performed a post hoc analysis of a prospective cohort study that involved assessing the risk of NAFLD in non-obese Chinese residents from January 2010 to December 2014. The incidence of NAFLD during the 5-year follow-up was identified as the endpoint. Cox proportional hazards regression analysis was used to evaluate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the incidence of NAFLD. Receiver operating characteristic (ROC) curve analysis was conducted to estimate the predictive power of TyG-BMI and its components for NAFLD. Subgroup analysis was performed to better understand other factors that may affect the association between TyG-BMI and NAFLD to identify potential special populations. Results During the follow-up period, 841 (8.61%) of 9767 non-obese subjects who met the screening criteria were diagnosed with NAFLD. After confounding factors were fully adjusted for, the HR of NAFLD was 3.09 (95% CI 2.63–3.63) per standard deviation (SD) increase in TyG-BMI. Furthermore, TyG-BMI had a strong predictive value (area under ROC = 0.85; 95% CI 0.84–0.86) for the incidence of NAFLD, with a specificity of 0.73 and sensitivity of 0.82. Additionally, in the male population, each SD increase in TyG-BMI was linked to an increased risk of NAFLD (HR = 2.85, 95% CI 2.30–3.53), but the risk was higher in the female population (HR = 3.58, 95% CI 2.80–4.60). Gender and TyG-BMI interacted significantly with NAFLD incidence (P < 0.0001). Conclusion In the normolipidaemic and non-obese subset of the Chinese population, an increase in TyG-BMI is related to an increased incidence of NAFLD. TyG-BMI may have clinical significance in identifying groups at high risk of NAFLD.

WHtR may be a Better and Stronger Indictor for Fatty Liver: A Population-Based Cross-sectional Comparison Study of Anthropometric and Metabolic Indices for Identification Fatty Liver in China

“…As expected, several anthropometric or metabolic indices such as skeletal muscle mass [16], atherogenic index [17,18], Body Mass Index (BMI) [19], the ratio of Triglyceride (TG) to High-Density Lipoprotein cholesterol [20], visceral adipose tissue [21], Total cholesterol (TC) to High-Density Lipoprotein cholesterol ratio [22] and Triglyceride Glucose (TyG) [23,24], as well as blood pressure [25] had been reported to be associated with FL in both cross-sectional and cohort studies. However, most existing studies mainly focused on only one or two indices, which might have limitations for predicting FL considering the high complexity of the pathogenesis of FL.…”

“…The fatty liver-related indices, including WHtR, WHR, BMI, AVI, AIP, TyG and ALT/AST were calculated using the following equations [18,19,23,27]. BMI = weight (kg) / height 2 (m) WHtR = WC (cm) / height (cm) WHR = WC (cm) / HC (cm) AVI = [2 × WC 2 (cm) + 0.7×(WC − HC) 2 (cm)]/1000 AIP = Ln [TG (mmol/L)) / HDL (mmol/L)] TyG = Ln [TG (mg/dL) × FBG (mg/dL)/2] ALT/AST = ALT(U/L) / AST (U/L) Diagnoses of FL was based on the four abdominal ultrasonography standard (parenchymal brightness, hepatorenal echo contrast, deep beam attenuation, and bright vessel walls) by experienced radiologists with expertise in liver imaging [28,29].…”

The usefulness of obesity and lipid-related indices to predict the presence of Non-alcoholic fatty liver disease

“…The conclusions of several existing studies are controversial, and do not include TyG indexrelated parameters [21][22][23]. According to some recent studies, TyG index-related parameters are promising new indicators for predicting NAFLD [14,24]. It is critical to further compare TyG index-related parameters with other obesity and lipid-related indices and identify more useful biomarkers for predicting NAFL D. Therefore, the present study was designed to evaluate the best obesity and lipid-related indices for predicting NAFLD through an epidemiological survey of 14251 from the general population who underwent health screening.…”

Association between triglyceride–glucose index and nonalcoholic fatty liver disease in type 2 diabetes mellitus

“…Another study showed that the association of TyG and NAFLD risk was signi cantly stronger in nonobese subjects than that in obese ones [18]. Thus, the predictive power of TyG index for NAFLD risk was partially affected by BMI of the individuals.…”

“…Although most studies explored the relationship between the TyG index and NAFLD risk, these studies focused on the general population [15,18,19]. Our present study focused on the associations of the TyG index, glycemic parameters, and lipid parameters with NAFLD in a T2DM population.…”