Glycated Hemoglobin as a Long-Term Predictor of Cardiovascular Outcomes in Patients Undergoing Carotid Endarterectomy

Abstract

Background: In noncardiac surgery, several biomarkers are known to play a role in predicting long-term complications, such as major adverse cardiovascular events (MACE), myocardial infarction, or death. Carotid endarterectomy (CEA) is considered a low to medium-risk surgery for carotid stenosis aimed at preventing stroke events. Hemoglobin A1c is a biomarker with potential prognostic value regarding MACE. This study aims to assess the potential role of HbA1c as a short and long-term predictor of all-cause mortality and MACE in patients undergoing CEA. Methods: A post hoc analysis was performed using data from a prospective database of patients who underwent carotid endarterectomy (CEA) under regional anesthesia (RA) at a tertiary referral center between January 2014 and December 2023. Patients with available HbA1c measurements taken up to three months before surgery were included and categorized into two groups based on an HbA1c threshold of 6.5%. Kaplan-Meier survival analysis and multivariable Cox regression models were used to assess the impact of HbA1c levels on time-dependent outcomes. The primary outcome was the incidence of long-term major adverse cardiovascular events (MACE) and all-cause mortality. Secondary outcomes included the incidence of stroke, acute myocardial infarction (AMI), acute heart failure (AHF), and major adverse limb events (MALE). Results: A total of 65 patients who underwent CEA were evaluated. The mean age was 71.4 ± 8.5 years, with 53 (81.5%) males, and the median follow-up period was 30 [13.5-46.4] months. Patients with HbA1c ≥ 6.5% were significantly younger (68.8 ± 8.8 vs. 73.8 ± 7.9 years, p=0.015). Kaplan-Meier survival analysis revealed a significant association between HbA1c levels and stroke incidence (log-rank p=0.045), with a trend toward increased major adverse cardiovascular events (MACE) (log-rank p=0.038). Multivariable analysis confirmed that HbA1c was an independent predictor of major adverse limb events (MALE) (aHR: 3.387, CI: 1.078-10.643, p=0.037), while its association with stroke did not reach statistical significance (aHR: 3.205, CI: 0.959-10.716, p=0.059). No significant associations were found between HbA1c and myocardial infarction (p=0.415), acute heart failure (p=0.545), or all-cause mortality (p=0.246). Conclusion: HbA1c has been demonstrated to predict long-term MACE, Stroke and MALE following CEA independently. While its role in predicting other major cardiovascular events remains inconclusive, HbA1c serves as a readily available and cost-effective biomarker for vascular risk stratification in this population.