Prognostic value of triglyceride glucose index in population at high cardiovascular disease risk

BACKGROUND: Early identification of populations at high cardiovascular disease (CVD) risk and improvement of risk factors can significantly decrease the probability of CVD development and improve outcomes. Insulin resistance (IR) is a CVD risk factor. The triglyceride glucose (TyG) index is a simple and reliable index for evaluating IR. However, no clinical studies on the prognostic value of the TyG index in a high risk CVD population have been conducted. This study evaluated the relationship between the TyG index and prognosis in a high risk CVD population. METHODS: This study enrolled 35,455 participants aged 35–75 years who were at high CVD risk and visited selected health centers and community service centers between 2017 and 2021. Their general clinical characteristics and baseline blood biochemical indicators were recorded. The TyG index was calculated as ln[fasting triglyceride (mg/dl)× fasting blood glucose (mg/dl)/2]. The endpoints were all-cause death and cardiovascular death during follow-up. Cox proportional hazard models and restricted cubic spline (RCS) analysis were used to evaluate the correlation between the TyG index and endpoints. RESULTS: In the overall study population, the mean age of all participants was 57.9 ± 9.6 years, 40.7% were male, and the mean TyG index was 8.9 ± 0.6. All participants were divided into two groups based on the results of the RCS analysis, with a cut-off value of 9.83. There were 551 all-cause deaths and 180 cardiovascular deaths during a median follow-up time of 3.4 years. In the multivariate Cox proportional hazard model, participants with a TyG index ≥ 9.83 had a higher risk of all-cause death (Hazard ratio [HR] 1.86, 95% Confdence intervals [CI] 1.37–2.51, P<0.001) and cardiovascular death (HR 2.41, 95%CI 1.47–3.96, P = 0.001) than those with a TyG index < 9.83. Subgroup analysis revealed that there was no interaction between the TyG index and variables in all subgroup analyses. CONCLUSIONS: The high TyG index was associated with an increased risk of all-cause death and cardiovascular death in people at high risk of CVD. This finding demonstrates the value of the TyG index in the primary prevention of CVD. TRIAL REGISTRATION: retrospectively registered, the registration number is K2022-01-005 and the date is 2022.01.30.