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.