Predictive effect of triglyceride‑glucose index on clinical events in patients with type 2 diabetes mellitus and acute myocardial infarction: results from an observational cohort study in China

Abstract

Background: Triglyceride glucose (TyG) index is considered a reliable alternative marker of insulin resistance and an independent predictor of cardiovascular (CV) outcomes. However, the prognostic value of TyG index in patients with type 2 diabetes mellitus (T₂DM) and acute myocardial infarction (AMI) remains unclear.

Methods: A total of 1932 consecutive patients with T₂DM and AMI were enrolled in this study. Patients were divided into tertiles according to their TyG index levels. The incidence of major adverse cardiac and cerebral events (MACCEs) was recorded. The TyG index was calculated as the ln [fasting triglycerides (mg/dL) × fasting plasma glucose (mg/dL)/2].

Results: Competing risk regression revealed that the TyG index was positively associated with CV death [2.71(1.92 to 3.83), p < 0.001], non-fatal MI [2.02(1.32 to 3.11), p = 0.001], cardiac rehospitalization [2.42(1.81 to 3.24), p < 0.001], revascularization [2.41(1.63 to 3.55), p < 0.001] and composite MACCEs [2.32(1.92 to 2.80), p < 0.001]. The area under ROC curve of the TyG index for predicting the occurrence of MACCEs was 0.604 [(0.578 to 0.630), p < 0.001], with the cut-off value of 9.30. The addition of TyG index to a baseline risk model had an incremental effect on the predictive value for MACCEs [net reclassification improvement (NRI): 0.190 (0.094 to 0.337); integrated discrimination improvement (IDI): 0.027 (0.013 to 0.041); C-index: 0.685 (0.663 to 0.707), all p < 0.001].

Conclusions: The TyG index was significantly associated with MACCEs, suggesting that the TyG index may be a valid marker for risk stratification and prognosis in patients with T₂DM and AMI. Trial registration Retrospectively registered.

Keywords: Acute myocardial infarction (AMI); Insulin resistance (IR); Major adverse cardiac and cerebral events (MACCEs); Triglyceride-glucose index (TyG index); Type 2 diabetes mellitus (T2DM).

Fig. 1

Competing risk regression curves for CV death, non-fatal MI, non-fatal stroke, cardiac rehospitalization, revascularization and composite MACCEs of the TyG ≤ 8.91 group (Tertile 1, yellow line), the 8.91 < TyG < 9.54 group (Tertile 2, green line) and the TyG ≥ 9.54 group (Tertile 3, red line). TyG, triglyceride-glucose index; CV, cardiovascular; MI, myocardial infarction; MACCEs, major adverse cardiac and cerebral events

Fig. 2

The receiver operating characteristic (ROC) curves of the TyG index as a marker to predict composite MACCEs in patients with T₂DM and AMI. The area under ROC curves (AUCs) of the TyG index for predicting the occurrence of MACCEs was 0.604 (95% CI 0.578–0.630; p < 0.001). The cut-off value of TyG index to predict MACCEs was 9.30, the sensitivity was 0.552, and the specificity was 0.613

Fig. 3

Forest plot of composite MACCEs according to different subgroups. Adjusted model included age, gender, BMI, SBP, DBP, previous MI, past PCI, history of stroke, current/ex-smoker, WBC, eGFR, albumin, TC, TGs, HDL-C, LDL-C, LVEF, hemoglobin, medication used before admission(antiplatelet agent, ACEI/ARB, beta-blocker and statins), in-hospital treatment(PCI/CABG, antiplatelet agent, ACEI/ARB, beta-blocker and statins) and hypoglycemic agents(metformin, alpha-glucosidase inhibitor, DPP-4i and insulin). MACCE, major adverse cardiac and cerebral events; TyG, triglyceride-glucose index; BMI, body mass index; HT, hypertension; eGFR, estimated glomerular filtration rate; LVEF, left ventricular ejection fraction; NSTEMI, Non-ST-segment elevation myocardial infarction; STEMI, ST-elevation myocardial infarction; SBP, systolic blood pressure; DBP, diastolic blood pressure; MI, myocardial infarction; PCI, percutaneous coronary intervention; WBC, white blood cell; TC, total cholesterol; TGs, triglycerides; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; ACEI/ARB, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker; CABG, coronary artery bypass graft; DPP-4i, dipeptidyl peptidase-4 inhibitor; HR, hazard ratio; CI, confidence interval; Ref., reference(TyG ≤ 8.91 group)