Association Between the Triglyceride–Glucose Index and Incident Chronic Severe Pain in Middle‐Aged and Older Chinese Adults: A Nationwide Cohort Study

Background Insulin resistance (IR) has been linked to chronic severe pain (CSP) in previous studies. The triglyceride–glucose (TyG) index serves as an indicator of IR. However, whether TyG control level affects the further CSP incidence has not been well established. In this study, we aimed to identify the association between TyG control level and the risk of CSP. Methods Participants with a continuous statement of severe pain in two consecutive waves of investigation from the China Health and Retirement Longitudinal Study were defined as CSP. The TyG control level was divided into four classes. The association between the baseline TyG and TyG control level CSP incidence was analyzed through logistic regression and restricted cubic spline analysis. Results A total of 113 (3.18%) of 3546 participants were diagnosed as CSP within 9 years. The TyG index has a significant correlation with high CSP incidence (OR = 1.51 (95% CI, 1.16–1.96), p = 0.020). Further research analyzed the trajectory of TyG changes. After adjusting for various confounding factors, comparing to Class 1 with the best control of TyG, the OR for Class 4 with the worst control was 2.30 (95% CI, 1.01–5.25) with p = 0.048. In restricted cubic spline regression, the relationship between the TyG index and cumulative TyG and CSP is linear. Conclusions The TyG index should be regarded as a simple indicator of CSP incidence. Continuous monitoring of the TyG index is more suitable for predicting CSP incident risk compared to a one‐time TyG measurement, and long‐term, well‐controlled management of the TyG index may be an efficient approach to reduce the risk of CSP incidence.