Diagnostic potential of waist–triglyceride index, triglyceride–glucose index and related indices for the detection of metabolic syndrome in Nepali adults: A cross-sectional study

Metabolic Syndrome (MetS) is a major public health concern associated with elevated risk of cardiometabolic diseases. Conventional diagnostic criteria for MetS require multiple clinical and biochemical measurements, limiting feasibility in resource-constrained settings. Novel anthropo-metabolic indices offer a simplified, surrogate approach for risk prediction and stratification. This study aimed to evaluate the diagnostic performance of the triglyceride-glucose (TyG) index, waist-triglyceride index (WTI), and their derivatives TyG-waist circumference (TyG-WC), TyG-waist-to-height ratio (TyG-WHtR), and TyG-body mass index (TyG-BMI) for detecting the risk of MetS in Nepali adults.

A cross-sectional study was conducted among 1116 adults (424 females, 692 males) recruited from the premises of Manipal Teaching Hospital, Pokhara, Nepal. Baseline sociodemographic, anthropometric, and biochemical data were collected. MetS was defined using National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Indices were calculated using standard formulae and their associations with MetS were examined using Spearman's correlation, multivariable logistic regression, and receiver operating characteristic (ROC) curve analyses.

All indices demonstrated significant diagnostic capability for the detection of MetS (p < 0.001). The TyG index showed the highest overall accuracy, with area under the curve (AUC) of 0.920 in females and 0.874 in males. At optimal sex-specific cutoffs (≥8.66 for females, ≥8.87 for males), TyG demonstrated excellent sensitivity (female: 88.40 %, male: 85.55 %) and specificity (female: 88.00 %, male: 81.20 %). WTI and TyG-WC showed strong performance in identifying hypertriglyceridemia and central obesity, respectively. Logistic regression confirmed the TyG index as the strongest independent predictor of MetS (adjusted odds ratio (AOR): females = 58.59, males = 30.94, p < 0.001). Predictive accuracy was lower for hypertension and low high density lipoprotein cholesterol (HDL-C). Comparative AUC analysis revealed greater index variability among females than males.

The TyG, TyG-WC and WTI are found to be robust, gender-specific tools for diagnosis of MetS and its components in Nepali adults. Their simplicity, affordability and high diagnostic accuracy support their integration into large-scale MetS screening in resource-limited settings. Sex-specific cutoffs enhance the precision of risk assessments, emphasizing the need for tailored screening strategies.