Evaluation of the long-term prognostic ability of triglyceride-glucose index for elderly acute coronary syndrome patients: a cohort study

Abstract

Background: With the advancement of the world population aging, more attention should be paid to the prognosis of elderly patients with acute coronary syndrome (ACS). Triglyceride-glucose (TyG) index is a reliable indicator of insulin resistance (IR) and is closely related to traditional risk factors of cardiovascular disease (CVD). However, the effect of TyG index on the prognosis of long-term adverse events in elderly ACS patients has not been reported. This study evaluated the prognostic power of TyG index in predicting adverse events in elderly ACS patients.

Methods: In this study, 662 ACS patients > 80 years old who were hospitalized from January 2006 to December 2012 were enrolled consecutively and the general clinical data and baseline blood biochemical indicators were collected. The follow-up time after discharge was 40-120 months (median, 63 months; interquartile range, 51‒74 months). In addition, the following formula was used to calculate the TyG index: Ln [fasting TG (mg/dL) × FBG (mg/dL)/2], and patients were divided into three groups according to the tertile of the TyG index.

Results: The mean age of the subjects was 81.87 ± 2.14 years, the proportion of females was 28.10%, and the mean TyG index was 8.76 ± 0.72. The TyG index was closely associated with the traditional risk factors of CVD. In the fully-adjusted Cox regression model, the Hazard ratio (95% CI) of all-cause mortality (in tertile 3) was 1.64 (1.06, 2.54) and major adverse cardiac event (MACE) (in tertile 3) was 1.36 (1.05, 1.95) for each SD increase in the TyG index. The subgroup analyses also confirmed the significant association of the TyG index and long-term prognosis.

Conclusion: The TyG index is an independent predictor of long-term all-cause mortality and MACE in elderly ACS patients.

Keywords: Acute coronary syndrome; Elderly patient; Insulin resistance; Prognosis; Triglyceride glucose index.

Fig. 1

Kaplan–Meier survival curves of survival probability (A) and survival probability of MACE-free (B) for the elderly ACS patients

Fig. 2

Forest plot investigating the association between the TyG index and all-cause mortality in different subgroups. Adjusted for age, gender, BMI, SBP, DBP, LVEF, Gensini score, hypertension, diabetes, hyperlipidemia, previous MI, previous stroke, CKD, current smoking, TC, LDL-C, HDL-C, eGFR, UA, aspirin, clopidogrel, statin, β-blocker, ACEI/ARB, LM lesion, multivessel lesion except for the stratified variable

Fig. 3

Forest plot investigating the association between the TyG index and MACE in different subgroups. Adjusted for age, gender, BMI, SBP, DBP, LVEF, Gensini score, hypertension, diabetes, hyperlipidemia, previous MI, previous stroke, CKD, current smoking, TC, LDL-C, HDL-C, eGFR, UA, aspirin, clopidogrel, statin, β-blocker, ACEI/ARB, LM lesion, multivessel lesion except for the stratified variable