The association between the triglyceride-glucose index and vulnerable plaques in patients with type 2 diabetes mellitus: insights from coronary computed tomography angiography

Abstract

Background: The triglyceride‒glucose index (TyG index) has been verified to be a useful predictor of insulin resistance (IR), and is associated with the occurrence of acute coronary syndrome (ACS). However, the effect of the TyG index on vulnerable plaques (VP), which were identified when at least two high-risk features are present within the same lesion, in type 2 diabetes mellitus (T2DM) patients is not fully understood. This study aimed to explore the association between the TyG index and the presence of VP.

Methods: We retrospectively enrolled 2056 T2DM patients who underwent coronary computed tomography angiography (CCTA) examinations at West China Hospital from February 2017 to February 2022. These patients were divided into four groups on the basis of the quartiles of the TyG index. The high-risk coronary plaque features, vulnerable plaques, plaque type, coronary artery stenosis, segment involvement score (SIS), segment stenosis score (SSS) and multivessel disease (MVD) based on CCTA data were evaluated and compared among the four groups.

Results: Patients with a higher TyG index had more noncalcified and mixed plaques, high-risk plaque features, vulnerable plaques and fewer calcified plaques (P < 0.05 for all). The proportion of patients with high-risk plaque features, including low-attenuation noncalcified plaques, positive remodeling and "napkin ring" sign was associated with the TyG index (P for trend < 0.05 for all). Multivariate analysis revealed that the TyG index was significantly associated with vulnerable plaques in T2DM patients [OR = 1.23 (95% CI 1.00-1.51), P = 0.046]. Subgroup analysis revealed that the association between the TyG index and vulnerable plaques varied with age and the prevalence of cardiovascular (CVD) symptoms, even after controlling for confounding factors (P for interaction < 0.05 for both).

Conclusion: The TyG index was independently associated with vulnerable plaques of the coronary artery among patients with T2DM. The TyG index could be regarded as a marker to reduce the incidence of cardiovascular events in the targeted population of T2DM patients.

Keywords: Atherosclerosis; Coronary artery plaque; Coronary computed tomography angiography; TyG index; Type 2 diabetes mellitus.

Fig. 1

Flowchart of participant selection

Fig. 2

Schematic diagram of the degree of coronary artery stenosis and coronary artery segmentation. In this example, plaques distribute on proximal RCA, mid-LAD and proximal LCx. SIS was calculated by the number of coronary artery segments observed with plaques, which was 3 out of a possible 16 in this example. SSS was calculated by the minimal plaque in the proximal RCA (scored 1), mild plaque in the mid-LAD (scored 2) and severe plaque in the proximal LCx (scored 4). Thus, the SSS was 7 out of a possible 80. LAD Left anterior descending artery, LCx Left circumflex, RCA Right coronary artery, SIS Segment involvement score, SSS Segement stenosis score.

Fig. 3

A Curvature plane reconstruction image of the coronary artery in a 69-year-old male with high TyG index (in T4 group): low-attenuation noncalcified plaque (grey arrow), spotty calcification (white arrow) and positive remodeling can be seen in the left anterior descending artery (LAD); B Measurement of the positive remodelling index of the plaque in panel A remodelling index = 1.27 {lesion plaque area (0.52 cm)/ reference area (0.41 cm)}; C Napkin ring sign in a 68-year-old male with high TyG index (in T4 group)

Fig. 4

Association between the TyG index and high-risk plaque feature: a low-attenuation noncalcified plaque; b positive remodeling; c spotty Calcification; d napkin-ring sign