The triglyceride-glucose index: updating evidence from clinical settings to molecular mechanisms in ageing-related cerebrovascular diseases.

Cerebrovascular ageing is a complex process characterized with increased vessel stiffness, decreased sensitivity to vasodilators and vasoconstrictors, and reduced angiogenesis, which is mediated via time-dependent manner. The triglyceride-glucose (TyG) index, calculated by ln[fasting triglycerides (TG) (mg/dl) × fasting blood glucose (FBG) (mg/dl)/2], has recently been evidenced as a reliable surrogate of insulin resistance (IR). Currently extensive studies provide robust statistical evidence of the predictability of the TyG index in the development and prognosis of ageing-related cerebrovascular diseases. Yet the application of the TyG index in ageing-related cerebrovascular diseases has not been systemically evaluated in clinical practice, and also the underlying shared mechanism has not been disentangled. Therefore, revealing novel treatment strategies and identifying the potential mechanisms targeting the TyG index is of significant importance. On this basis, more studies are warranted to standardize the optimal care taken in clinical referring TyG index, which will benefit patients with high cerebrovascular diseases risk. Here, we searched the Cochrane Library, Embase, Medline, Web of Science, PubMed, and other relevant English databases and related websites from inception to August 2025 and reviewed existing literature and describe the current scope and impact of the TyG index on ageing-related cerebrovascular diseases, aiming to highlight its application value and underlying mechanism.