The triglyceride-glucose index predicts ischemic heart disease risk in Koreans: a prospective study using National Health Insurance Service data

Background: Ischemic heart disease (IHD) without diabetes is considered an important challenge to human health and is associated with a poor prognosis, as well as a lack of health awareness. We prospectively investigated the relationship between the triglyceride-glucose (TyG) index, a surrogate marker of early insulin resistance, and incident IHD risk in a large cohort of nondiabetic Korean adults using National Health Insurance Service data. Methods: We assessed 16,455 participants (8426 men and 8029 women) without diabetes using data from a health risk assessment study (HERAS) and Korea Health Insurance Review and Assessment (HIRA) data. The participants were divided into four groups according to TyG index quartiles, calculated as ln [fasting triglycerides (mg/dL) × fasting plasma glucose (mg/dL)/2]. We prospectively assessed hazard ratios (HRs) with 95% confidence intervals (CIs) for IHD using multivariate Cox proportional-hazards regression models over a 50-month period that followed the baseline survey. Results: During the follow-up period, 322 (2.0%) participants developed IHD. HRs of IHD for TyG index quartiles 2–4 were 1.61 (95% CI 1.05–2.48), 1.85 (95% CI 1.21–2.81), and 2.29 (95% CI 1.50–3.51), respectively, after adjusting for age, sex, body mass index, smoking status, alcohol intake, and physical activity. Conclusions: A higher TyG index precedes and significantly predicts future IHD among nondiabetic Koreans. Accordingly, the TyG index may be a useful measure in assessing cardiovascular risk for nondiabetic adults in the preclinical stage.