Potential screening indicators for early diagnosis of NAFLD/MAFLD and liver fibrosis: Triglyceride glucose index-related parameters

Abstract

Importance: Homeostatic model assessment for insulin resistance (HOMA-IR) and triglyceride glucose (TyG) index-related parameters [TyG index, triglyceride glucose-waist circumference (TyG-WC), triglyceride glucose-waist-to-height ratio (TyG-WHtR), and triglyceride glucose-body mass index (TyG-BMI)] are gradually considered as convenient and alternative indicators for insulin resistance in various metabolic diseases, but the specific diagnostic capacity and the comparison of the parameters in non-alcoholic fatty liver disease (NAFLD), metabolic-associated fatty liver disease (MAFLD), and liver fibrosis remain uncertain.

Objective: To comprehensively assess and compare the diagnostic accuracy of the above parameters in NAFLD, MAFLD, and liver fibrosis and identify the appropriate indicators.

Methods: A total of 1,727 adults were enrolled from the 2017-2018 National Health and Nutrition Examination Surveys. Logistic regressions were used to identify the parameters significantly associated with NAFLD, MAFLD, and liver fibrosis; receiver operating characteristic (ROC) curves were used to evaluate and compare their diagnostic capacity. Subgroup analyses were conducted to validate the concordance, and the optimal cutoff values were determined according to the Youden's indexes.

Results: Significant differences were observed between quartile-stratified HOMA-IR and TyG index-related parameters across the NAFLD, MAFLD, and liver fibrosis (P < 0.05). All variables were significantly predictive of different disease states (P < 0.05). The top three AUC values are TyG-WC, TyG-WHtR, and TyG-BMI with AUCs of 0.815, 0.809, and 0.804 in NAFLD. The optimal cutoff values were 822.34, 4.94, and 237.77, respectively. Similar values and the same trend of the above three indexes could be observed in MAFLD and liver fibrosis. Subgroup analyses showed consistent results with the primary research, despite some heterogeneity.

Conclusions: TyG-WC, TyG-WHtR, and TyG-BMI can be used for early screening of NAFLD and MAFLD. These three parameters and HOMA-IR were more suitable for assessing metabolic risks and monitoring disease progression in patients with NAFLD.

Keywords: MAFLD; NAFLD; NHANES; ROC curves; TyG index–related parameters.