Cumulative of c-reactive protein-triglyceride glucose index exposure and risk of diabetes in middle-aged and older Chinese adults: findings from a national longitudinal cohort.

BACKGROUND: The C-reactive protein-triglyceride glucose index (CTI) was a new biomarker to assess systemic inflammation and metabolic disturbances. However, research on its association with diabetes remained limited. This study aimed to investigate the association between CTI and the risk of developing new-onset diabetes. METHODS: This study employed a prospective observational design, focusing on middle-aged and elderly Chinese adults. Multivariate Cox regression analysis were used to assess the dose-response association between the CTI and the cumulative exposure of CTI (CumCTI) with diabetes risk. The K-means clustering was employed to classify the CTI trajectories. RESULTS: A total of 3,742 participants without diabetes were enrolled in this study. Over a 5-year follow-up period, 264 individuals developed diabetes, yielding an incidence rate of 7.5%. Overall, higher levels of CTI exposure were significantly associated with an increased risk of diabetes. Specifically, each 1-unit increment in CTI corresponded to a 35% elevation in diabetes risk (HR: 1.35; 95% CI: 1.14, 1.60), while each 1-unit increase in CumCTI was associated with 16% higher risk (HR: 1.16; 95% CI: 1.09, 1.25). When comparing exposure trajectories, individuals with persistently high CTI exposure (Cluster1) exhibited a 1.25 times elevated risk compared to those with consistently low exposure levels (Cluster3) (HR: 2.25; 95% CI: 1.53, 3.31). CONCLUSION: Elevated CTI exposure was significantly correlated with an increased risk of diabetes, highlighting its potential role in diabetes prediction, especially in the abnormal weight population. As a promising biomarker for diabetes risk monitoring, CTI might offer valuable insights for early detection and preventive strategies.