The relationship of insulin resistance estimated by triglyceride glucose index and coronary plaque characteristics

The triglyceride glucose (TyG) index is a useful surrogate marker for insulin resistance, which is an important risk factor for coronary artery disease (CAD). However, data on the relationship of the TyG index and coronary plaque characteristics are limited. This study included 2840 participants with near-normal renal function who underwent coronary computed tomography angiography. CAD was defined as the presence of any plaques, and obstructive CAD was defined as the presence of plaques with ≥50% stenosis. The relationship between the TyG index and noncalcified plaque (NCP), calcified or mixed plaque (CMP), and coronary artery calcium score (CACS) was evaluated. All participants were stratified into 4 groups based on the quartiles of the TyG index. The prevalence of CAD and obstructive CAD significantly increased with increasing quartiles. The risk for NCP and obstructive NCP was not different among all groups. However, compared with group I (lowest quartile), the risk for CMP was higher in groups III (odds ratio [OR]: 1.438) and IV (highest quartile) (OR: 1.895) (P < .05), and that for obstructive CMP was higher in groups II (OR: 1.469), III (OR: 1.595), and IV (OR: 2.168) (P < .05). Multivariate regression analysis showed that the TyG index was associated with an increased risk for CAD (OR: 1.700), obstructive CAD (OR: 1.692), and CACS >400 (OR: 1.448) (P < .05). The TyG index was independently associated with the presence and severity of CAD due to an increased risk for CMP.