Cumulative exposure and dynamic trajectories of the C-reactive protein-triglyceride-glucose index versus the Cholesterol, high-density lipoprotein, and glucose index for incident hypertension prediction: a national cohort study

Background While the C-reactive protein-triglyceride-glucose (CTI) and cholesterol–high-density lipoprotein–glucose (CHG) indices have emerged as potent surrogates for inflammatory-metabolic status, the long-term effects of their sustained accumulation are not yet clearly understood. Specifically, the predictive divergence between cumulative CTI (cuCTI) and CHG (cuCHG) in determining incident hypertension remains a critical knowledge gap in aging Chinese cohorts. Methods Leveraging a nationwide longitudinal cohort from the China Health and Retirement Longitudinal Study (CHARLS), we modeled the cumulative burden of CTI and CHG by integrating temporal data from Wave 1 through Wave 3. We then used multivariable Cox proportional hazards models to assess associations and restricted cubic splines (RCS) for dose-response relationships. K-means clustering identified trajectory patterns. To gauge the predictive performance at 7 and 9 years, we analyzed time-dependent ROC curves, alongside the C-index, NRI, and IDI. Finally, our findings were further subjected to subgroup and sensitivity analyses to test their robustness. Results During follow-up, 437 (15.6%) participants developed hypertension. Both elevated cuCTI and cuCHG significantly increased hypertension risk. Multivariable Cox regression analysis unveiled a clear difference in risk magnitude: participants in the highest quartile of cuCTI faced a two-fold risk of hypertension (HR = 2.04; 95% CI: 1.55–2.68), surpassing the 58% increase seen with cuCHG (HR = 1.58; 95% CI: 1.20–2.06). Crucially, cuCTI demonstrated superior predictive accuracy in time-dependent ROC analysis (9-year DeLong P = 0.010). Adding cuCTI to the fully adjusted model significantly improved the C-index at both 7 and 9 years, whereas cuCHG did not. Furthermore, cuCTI showed stronger gains in NRI and IDI compared to cuCHG (all P < 0.05). Subgroup and sensitivity analyses also showed consistent results. Conclusion Although both indices serve as independent predictors, cuCTI offers superior predictive power, likely by capturing the synergistic detriment of systemic inflammation and insulin resistance. These findings substantiate the imperative of monitoring cumulative inflammatory-metabolic load for the early stratification of hypertension risk.