Association between cumulative TyG/AIP-derived indices and terminal survival time in older patients with circulatory...

As novel alternative indicators of insulin resistance (IR), the triglyceride-glucose (TyG) and atherogenic index of plasma (AIP) are closely associated with the occurrence and progression of circulatory system diseases (CSD). However, it remains unclear whether TyG-derived indices (TyG, TyG-BMI, TyG-WC, TyG-WHtR) and AIP-derived indices (AIP, AIP-BMI, AIP-WC, AIP-WHtR) are associated with the terminal survival time of older patients with CSD.

A dynamic cohort study was conducted involving older adults aged ≥ 60 years with the underlying cause of death attributed to CSD and who had completed at least three follow-ups. Cumulative TyG- and AIP-derived indices were calculated from longitudinal data. Logistic regression (LR), generalized linear models (GLM), generalized estimating equations (GEE), and restricted cubic splines (RCS) were used to analyze the association between each cumulative index and terminal survival time. Subgroup analyses, receiver operating characteristic (ROC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were conducted to assess the robustness and predictive performance of each index.

A total of 2302 participants were included, with a median follow-up time of 34.10 months and a median terminal survival time of 12 months. After adjusting for covariates, both LR, GLM, GEE, and RCS showed that higher cumulative TyG- and AIP-derived indices were associated with shorter terminal survival time, with nonlinear relationships observed. Subgroup analysis revealed that the cumulative TyG- and AIP-derived indices were generally significantly associated with terminal survival time across age and gender strata (except for the cumulative AIP index in females), and significant age interaction was observed for cumulative TyG-BMI, TyG-WC, and TyG-WHtR. The results of ROC, NRI, and IDI indicated that the cumulative indices of TyG-BMI and TyG-WC significantly outperform other indicators in predictive efficacy.

Reducing TyG- and AIP-derived indices may help prolong terminal survival time in older patients with CSD. Furthermore, monitoring TyG-BMI and TyG-WC holds potential value for terminal survival time and may be considered for future integration into comprehensive assessment systems.