The triglyceride-glucose index is a predictor for cardiovascular events and all-cause mortality in young and middle-aged patients with metabolic syndrome

Abstract Aims The association between the triglyceride-glucose (TyG) index and cardiovascular risk in young and middle-aged individuals with Metabolic syndrome (MetS) remains unclear. This study aimed to investigate the relationship between baseline TyG index and cardiovascular events and all-cause mortality in these patients among American adults. Methods This study enrolled 4937 young and middle-aged patients with MetS from the National Health and Nutrition Examination Survey (1999–2018). Mortality outcomes were determined by linking to National Death Index records up to December 31, 2019. Multivariate Cox proportional hazards models were constructed to analyze explore the associations between baseline TyG index and cardiovascular events or all-cause mortality. Non-linear correlations were explored using restricted cubic splines, and a two-piecewise Cox proportional hazards model for both sides of the inflection point was constructed. Results During the up to 9.3 years follow-up period, a total of 463 all-cause deaths and 143 cardiovascular events were recorded. The multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) escalate from the lowest to the highest TyG index quartile. Specifically, for cardiovascular events, the HRs range from 1.00 (reference) to 2.29 (1.22, 4.31) with a significant trend (P = 0.004). For all-cause mortality, the HRs vary from 1.00 (reference) to 1.59 (1.09, 2.32), also showing a significant trend (P = 0.003). The restricted cubic splines revealed a J-shaped association between the baseline TyG index with cardiovascular events and all-cause mortality in MetS patients. Conclusions The high TyG index was identified as an independent predictor of elevated rates of cardiovascular events among young and middle-aged patients with MetS. Additionally, a J-shaped curve pattern was observed in the association between these factors.