Relationship between hemoglobin A1C and characteristics of plaque vulnerability in stable coronary disease: an...

Area of Science:

• Cardiology
• Endocrinology
• Medical Imaging

Background:

• Diabetes mellitus significantly elevates cardiovascular event risk.
• Glycemic control, measured by hemoglobin A1c (HbA1c), is crucial for managing diabetic complications.
• Understanding the relationship between HbA1c and coronary plaque characteristics is vital for risk stratification.

Purpose of the Study:

• To investigate the impact of serum HbA1c levels on coronary plaque characteristics in patients with stable coronary disease.
• To correlate HbA1c levels with plaque morphology, including fibrous cap thickness and the prevalence of thin-cap fibroatheroma (TCFA).

Main Methods:

• Retrospective analysis of 261 patients with stable coronary disease undergoing optical coherence tomography (OCT).
• Patients were stratified into tertiles based on HbA1c levels (T1: <6.3%, T2: 6.3-7.8%, T3: ≥7.8%).
• OCT findings, including fibrous cap thickness (FCT) and TCFA prevalence, were compared across HbA1c tertiles.

Main Results:

• Significantly thinner fibrous cap thickness (FCT) was observed in the highest HbA1c tertile (T3) compared to T1 and T2 (p=0.03).
• Higher prevalence of thin-cap fibroatheroma (TCFA), a marker of vulnerable plaque, was found in T3 (33.3%) versus T1/T2 (19.5%, p=0.04).
• HbA1c showed an inverse correlation with FCT (p<0.01), and higher HbA1c was associated with smaller minimal lumen and reference lumen areas.

Conclusions:

• Elevated serum HbA1c levels in stable coronary disease patients are associated with thinner fibrous caps and a higher prevalence of vulnerable plaques (TCFA).
• These findings suggest that poorer glycemic control contributes to plaque instability, potentially increasing cardiovascular risk.
• OCT imaging provides valuable insights into how glycemic control influences coronary plaque morphology.