Association of the TyG-related indices with hypertension–diabetes comorbidity in middle-aged and older adults: a suburban community-based study

Background To investigate the associations between TyG-related indices and hypertension-diabetes comorbidity (HTN-DM) among middle-aged and older adults. Methods A total of 2854 participants (aged ≥ 45 years) living in a suburban community were included in this study. The collected information comprised three parts: baseline information, physical examination, and laboratory testing. Multivariable logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between TyG-related indices (TyG, TyG-BMI, and TyG-BRI) and HTN-DM. Restricted cubic splines (RCS) were used to model the dose-response relationships. Receiver operating characteristic (ROC) curves were applied to evaluate the discriminative performance of these indices. Results Among 2,854 participants, each 1-SD increment in TyG, TyG-BMI, and TyG-BRI conferred multivariable-adjusted ORs (95% CIs) of 3.16(2.75–3.64), 1.39(1.15–1.66), and 1.37(1.22–1.54), respectively (all P < 0.001). Corresponding ORs (95% CIs) comparing the highest versus lowest quartile were 30.99(16.97–62.97), 6.42(4.20-10.14), and 6.43(4.21–10.17), with significant dose-response trends (all P for trend < 0.001). RCS analysis revealed a linear relationship for TyG and nonlinear associations for TyG-BMI and TyG-BRI with HTN-DM. TyG showed the highest observed AUC (0.786) among the evaluated indices, followed by TyG-BMI (0.679) and TyG-BRI (0.633).Across all subgroup analyses, TyG remained consistently and positively associated with HTN-DM prevalence, and the interaction with sex was significant (P = 0.045). Conclusions This study revealed that TyG-related indices were associated with HTN-DM. RCS analysis indicated a linear association for TyG but nonlinear associations for TyG-BMI and TyG-BRI. Among the three indices, TyG showed the highest observed AUC. This finding suggests that composite indices incorporating BMI or BRI may not necessarily improve discriminative ability beyond TyG alone.