Linear Association of Derivatives of Triglyceride-Glucose Index with Incident Lower Limb Joint Pain in Middle-Aged and Older Chinese Adults: A Prospective Cohort Study.

Background: Metabolic factors play a critical role in the onset of lower limb joint pain, especially in middle-aged and older individuals. TyG and its derivatives, have emerged as promising indicators of insulin resistance, and are linked with several metabolic diseases, yet their relationships with lower limb joint pain remains insufficiently studied. Methods: This study utilized 9-year longitudinal data (2011-2020) from the China Health and Retirement Longitudinal Study (CHARLS). TyG and its derivatives were collected at baseline (2011). Incident lower limb joint pain was recorded during follow-up. The associations were evaluated using Multivariable Cox proportional hazards models, Restricted Cubic Spline (RCS), and Kaplan-Meier curves. The robustness of the findings was assessed by Fine-Gray competing risk model and subgroup analyses. Results: Among 6817 participants, 2909 (42.67%) developed lower limb joint pain. The highest incidence occurred in the fourth quartile of TyG-BMI, TyG-WHtR and TyG-WC, but not TyG alone. There existed significant positive associations of TyG-BMI ( Conclusion: These results highlight the importance of monitoring TyG derivatives, specifically adiposity-integrated indices (TyG-BMI and TyG-WHtR) for early clinical detection and intervention in high-risk individuals, and offer novel perspectives for the assessment and treatment of lower limb joint pain.