Relationship between preoperative high triglyceride-glucose index and myocardial injury following non-cardiac surgery in advanced-age patients: a retrospective cohort study

Background Myocardial injury after non-cardiac surgery (MINS) is a common and insidious postoperative complication. This study aimed to evaluate the relationship between the triglyceride-glucose index (TyG) and MINS in advanced-age patients. Methods We performed a single-center retrospective study including patients >= 65 years of age who underwent non-cardiac surgery. The relationship between TyG and MINS was investigated using univariate and multivariate logistic regression analyses. Multivariate logistic regression analysis involved three models: Model I adjusted for preoperative factors, Model II adjusted for surgery-related factors, and Model III adjusted for both preoperative and surgery-related factors. Propensity score matching (PSM) was used to reduce the confounding effects of covariates. Subgroup analyses were then performed to evaluate the relationship between TyG and MINS in various subsamples. Results A total of 7789 patients were studied, among whom 481 (6.2%) developed MINS. A cut-off value of TyG of 8.57 was determined using a receiver operating characteristic (ROC) curve to be associated with the best predictive performance. Participants with TyG >= 8.57 were at a higher risk of developing MINS than those with TyG < 8.57 [n = 273 (7.6%) vs. n = 208 (4.9%), respectively; p < 0.001]. The univariate analysis showed that TyG >= 8.57 was significantly associated with MINS in elderly patients [odds ratio (OR): 1.58; 95% confidence interval (95%CI): 1.32-1.91; p < 0.001)]. In multivariate logistic regression, adjustments were made for risk factors including age, sex, body mass index (BMI), hypertension, coronary heart disease, and duration of surgery, etc. The adjusted ORs for TyG >= 8.57 were 1.46 (95%CI: 1.17-1.82), p = 0.001; 1.46 (95%CI: 1.19-1.77), p < 0.001; and 1.43 (95%CI: 1.13-1.81), p = 0.003, in the three multivariate models, respectively. The relationship remained after PSM (adjusted OR: 1.35, 95% CI: 1.03-1.78, p = 0.029). Furthermore, the relationship between TyG and MINS remained in a number of subgroups in the sensitivity analyses, but not in participants with peripheral vascular stenosis. Conclusions A preoperative high TyG (>= 8.57) is associated with a higher risk of MINS in advanced-age patients undergoing non-cardiac surgery.