Triglyceride-glucose index predicts outcome in patients with chronic coronary syndrome independently of other risk factors and myocardial ischaemia

Aims The triglyceride-glucose (TyG) index, a surrogate marker of insulin resistance (IR), is a prognostic risk factor in the general population. We aimed to assess whether it is an independent predictor of outcome also in patients with chronic coronary syndrome (CCS). Methods and results TyG index was evaluated in 1097 consecutive patients (75% men, median age 72 years) with known (26%) or suspected coronary artery disease (CAD), undergoing stress-rest myocardial perfusion scintigraphy, and coronary angiography and followed up for a median of 4.5 years. Moderate/severe perfusion abnormalities during stress (summed stress score >7) were documented in 60% of patients, obstructive CAD in 74%, and 36% underwent early revascularization. TyG index was 8.9 (median, interquartile interval 8.6–9.2). Cardiac death or myocardial infarction occurred in 103 patients and all-cause death in 65. After correction for clinical risk factors, LV function and common bio-humoral variables, TyG index (HR 2.42, 95% CI 1.57–3.72, P < 0.001), and moderate/severe stress perfusion abnormalities (hazard ratio (HR) 2.17, 95% confidence interval (CI) 1.25–3.77, P < 0.001) independently predicted cardiac events. TyG index (HR 3.64, 95%CI 2.22–5.96, P < 0.001) and high-sensitivity C-reactive protein (HR 1.11, 95% CI 1.04–1.19, P = 0.002) independently predicted all-cause death. Conclusion In patients with CCS, the TyG index identifies a cardiometabolic profile associated with an additional risk of cardiac events, over the presence of myocardial ischaemia and independently of other clinical, common bio-humoral or imaging risk determinants.