Associations between triglyceride-glucose index and glaucoma risk in hypertensive adults: Evidence from a nationally representative cohort

BACKGROUND: The triglyceride-glucose (TyG) index and its obesity-related derivatives have emerged as surrogate markers for metabolic dysfunction. This study aimed to explore their associations with glaucoma in hypertensive adults in the U.S. using NHANES data. METHODS: A total of 2458 hypertensive participants aged 40 years or older from NHANES 2005-2008 were included. Glaucoma was defined according to ISGEO-compatible structural and functional criteria. TyG, TyG-BMI, TyG-WC, and TyG-WHtR were calculated using standard formulas. Logistic regression models, restricted cubic splines, ROC curves, and decision curve analysis (DCA) were used to assess associations and predictive performance. RESULTS: All TyG-related indices were positively associated with glaucoma in fully adjusted models. Individuals in the highest TyG quartile had more than twice the odds of glaucoma compared to the lowest quartile (OR = 2.05; 95 % CI: 1.69-2.48, p < 0.0001). TyG-BMI, TyG-WC, and TyG-WHtR also showed increased risks (ORs: 1.57, 95 % CI: 1.29-1.90, p < 0.0001; 1.69, 95 % CI: 1.39-2.04, p < 0.0001; 1.71, 95 % CI: 1.41-2.07, p < 0.0001, respectively). These associations were consistent across age, sex, and race subgroups. A linear relationship was found for TyG, while its derivatives displayed nonlinear trends. TyG showed the best discriminative ability (AUC = 0.831; 95 % CI: 0.804-0.858, p < 0.0001), exceeding BMI, WC, and WHtR. DCA revealed higher net benefit for TyG-based indices, particularly TyG-WHtR and TyG-WC. CONCLUSIONS: The TyG index and its derivatives are strong, independent predictors of glaucoma in hypertensive adults, with better diagnostic and clinical value than traditional obesity measures.