Triglyceride-glucose index as a cardiovascular risk marker: updated evidence, limitations, and future perspectives

Cardiovascular diseases (CVDs) remain the foremost cause of morbidity and mortality worldwide, accounting for a substantial burden on healthcare systems, economies, and society. Traditional risk factors do not fully explain residual cardiovascular risk, highlighting the role of insulin resistance (IR) as a key pathophysiological link between metabolic disorders and CVD. The triglyceride-glucose (TyG) index, a simple surrogate marker derived from fasting triglyceride and glucose levels, has emerged as a practical tool for assessing IR and cardiovascular risk. This review summarizes current evidence on the role of the TyG index in the development, progression, and prognosis of CVD. The TyG index reflects both hepatic and adipose tissue insulin resistance and has shown comparable or superior performance to traditional markers such as homeostatic model assessment of insulin resistance (HOMA-IR) but is easier to calculate and more feasible for routine clinical use. Large epidemiological and cohort studies have consistently demonstrated associations between elevated TyG values and increased risk of type 2 diabetes mellitus, coronary heart disease, myocardial infarction, stroke, peripheral arterial disease, and heart failure in both general and high-risk populations. Evidence suggests a dose-response relationship between TyG and cardiovascular outcomes, with higher TyG levels or adverse longitudinal trajectories conferring greater risk. Importantly, TyG has been linked to subclinical atherosclerosis, coronary microvascular dysfunction, and adverse cardiac remodeling, indicating its relevance in early disease stages. Sex-specific differences have been reported, with several studies showing stronger associations between TyG and cardiovascular risk in women. In addition, TyG has demonstrated prognostic value across diverse clinical settings, including acute and chronic coronary syndromes, myocardial infarction with nonobstructive coronary arteries, and heart failure. Despite these findings, the clinical implementation of the TyG index remains limited. Its incremental value beyond that of established risk models is inconsistent, and its predictive performance varies across populations, age groups, and ethnicities. Most available data are observational, with underrepresentation of non-Asian populations and younger individuals, and standardized clinical cutoff values have not been universally established. In conclusion, the TyG index is a simple, inexpensive, and widely accessible marker of insulin resistance with considerable potential for cardiovascular risk stratification. While current evidence supports its association with incident CVD, atherosclerotic burden, and adverse outcomes, further prospective, multiethnic studies are needed to define optimal thresholds, clarify its role alongside existing risk models, and determine whether TyG-guided strategies can improve clinical outcomes.