Association of triglyceride-glucose index with risk of cardiovascular disease among patients with prediabetes: population based prospective cohort study

BACKGROUND: The triglyceride-glucose (TyG) index was associated with an increased risk of cardiovascular disease (CVD) in patients with prediabetes. However, this association has not yet been evaluated in prospective studies. Hence, we aimed to investigate the association between the TyG index and the risk of incident CVD in patients with prediabetes. METHODS: Participants with prediabetes were enrolled from the Kailuan study and were followed up for clinical events until 2022. The exposure variable was TyG index. The primary outcomes were the incidence of CVD events, including ischemic heart disease and stroke, while the secondary outcomes were each specific type of CVD events. Cox proportional hazards regression models and restricted cubic spline analysis were used to calculate multivariable-adjusted hazard ratios and investigate exposure-response association, respectively. RESULTS: Over a mean follow-up period of 14.19 years, 13.81% (n = 2,537) of the 18,364 participants with prediabetes developed CVD events. Compared with participants in the lowest TyG index quartile (Q1, TyG index < 8.45), those in Q2 (TyG index 8.45-8.81), Q3 (TyG index 8.81-9.23), and Q4 (TyG index ≥ 9.23) were associated with an increased risk of CVD, with hazard ratios (HRs) of 1.18 (95% confidence interval [CI] 1.05-1.34), 1.29 (95% CI 1.15-1.46), and 1.45 (95% CI 1.28-1.63), respectively. For each unit increase in TyG index, the risk of CVD events increased by 12% in prediabetes patients. We also found a linear association between baseline TyG index and CVD events in prediabetes patients (P-non-linear = 0.12). CONCLUSIONS: TyG index is an independent risk factor for incident CVD in the prediabetes patients.