Dijin Xiao, Liang Zhou, Yingfeng Xiao, Cong Yu, Wenguang Chen, Jiwen Fan, En-Si Hong
Composite indices combining the TyG index with non-traditional lipid parameters were consistently associated with incident stroke in middle-aged and older Chinese adults. Derivable from routine glucose and lipid tests, these measures may serve as adjuncts for primary stroke risk assessment by reflecting the combined burden of insulin resistance and atherogenic dyslipidemia.
BACKGROUND: The triglyceride-glucose (TyG) index and non-traditional lipid parameters have been linked to cardiovascular and cerebrovascular risk, but longitudinal evidence on their combined utility for predicting incident stroke remains limited. We aimed to evaluate the associations between composite indices integrating the TyG index with seven non-traditional lipid parameters and incident stroke risk, and to determine whether these indices provide incremental predictive value beyond individual parameters.
METHODS: We analyzed data from the China Health and Retirement Longitudinal Study (2011-2018), including 7,578 stroke-free participants aged ≥45 years. Seven composite indices were calculated as the product of the TyG index and each non-traditional lipid parameter. Cox proportional hazards models, restricted cubic splines, ROC curves, NRI, IDI, and mediation analyses were employed.
RESULTS: During a median 7-year follow-up, 481 incident strokes occurred. After full adjustment, higher quartiles of most composite indices were associated with increased stroke risk, with TyG-LCI showing the strongest association (hazard ratio, 1.84; 95% CI, 1.37-2.47). Restricted cubic splines revealed non-linear exposure-response relationships. Composite indices yielded higher AUC values than conventional lipid parameters, and TyG-AIP, TyG-CRI-I, and TyG-LCI significantly improved risk reclassification and discrimination. The TyG index partially mediated the associations of CRI-II, AC, Non-HDL-C, and CRI-I with stroke (mediation proportions: 41.7%, 62.4%, 63.5%, 62.4%).
CONCLUSIONS: Composite indices combining the TyG index with non-traditional lipid parameters were consistently associated with incident stroke in middle-aged and older Chinese adults. Derivable from routine glucose and lipid tests, these measures may serve as adjuncts for primary stroke risk assessment by reflecting the combined burden of insulin resistance and atherogenic dyslipidemia.