Association of HbA1c and TyG Index with Major Adverse Events After Coronary Artery Bypass

Objectives: Major adverse events (MAEs) following coronary artery bypass grafting (CABG) represent important clinical outcomes affecting early postoperative morbidity and mortality. This study aimed to evaluate the association of preoperative glycated hemoglobin (HbA1c) and the triglyceride–glucose (TyG) index with the development of postoperative MAEs in patients undergoing elective CABG.
Methods: In this retrospective cohort study, data from 500 patients who underwent elective on-pump CABG between January 1, 2022, and December 31, 2023, were analyzed. Demographic characteristics, comorbidities, EuroSCORE II, and preoperative laboratory parameters were recorded. The TyG index was calculated using fasting triglyceride and glucose levels. The primary outcome was MAE, defined as the occurrence of at least one of the following: mortality, stroke, sepsis, or acute kidney injury. Logistic regression analyses were performed to identify predictors associated with MAE.
Results: MAE occurred in 110 patients (22%). Patients who developed MAE were older and had a higher prevalence of hypertension (p<0.001). However, no significant differences were observed between the groups in terms of HbA1c, fasting glucose, triglyceride levels, or the TyG index (p>0.05). In the multivariable analysis, age (OR: 1.03, 95% CI: 1.00–1.06; p=0.034) and hypertension (OR: 2.63, 95% CI: 1.58–4.36; p<0.001) were identified as independent predictors of MAE.
Conclusion: Preoperative HbA1c and the TyG index were not independent predictors of early postoperative MAE in patients undergoing elective CABG. In contrast, advanced age and the presence of hypertension were independently associated with an increased risk of MAE.

Keywords: Coronary artery bypass, glycated hemoglobin, insulin resistance, postoperative complications, triglycerides