The Role of the C‐Reactive Protein–Triglyceride Glucose Index in Predicting New‐Onset Chronic Diseases: Evidence From a Longitudinal Cohort Study

BACKGROUND: The C-reactive protein-triglyceride glucose index (CTI) is an emerging biomarker reflecting both systemic inflammation and insulin resistance. However, its association with the risk of new-onset chronic diseases remains insufficiently studied. METHODS: Data were derived from the China Health and Retirement Longitudinal Study between 2011 and 2020. A total of 9275 participants were included. This study assessed the associations between CTI levels and 14 chronic diseases, including hypertension, dyslipidemia, diabetes, stroke, liver disease, lung disease, osteoarthritis, and other diseases. Cox proportional hazards models were used to estimate the HRs for disease incidence, adjusting for confounders. Restricted cubic spline analyses were performed to explore potential nonlinear relationships. RESULTS: Elevated CTI levels were significantly associated with increased risks of new-onset hypertension (OR = 1.411, 95% CI: 1.274, 1.563), dyslipidemia (OR = 1.645, 95% CI: 1.508, 1.793), DM (OR = 1.932, 95% CI: 1.724, 2.165), stroke (OR = 1.676, 95% CI: 1.491, 1.883), and liver disease (OR = 1.279, 95% CI: 1.124, 1.455). A significant nonlinear association was observed between the CTI and osteoarthritis (p-nonlinear = 0.03) as well as stroke (p-nonlinear = 0.012). CONCLUSIONS: Elevated CTI is strongly associated with an increased risk of several chronic diseases, highlighting its potential value as a clinical risk assessment tool and predictive biomarker.