Relationship between hemoglobin A1C and characteristics of plaque vulnerability in stable coronary disease: an optical coherence tomography study

Comparison of Atherosclerotic Plaque Compositions in Diabetic and Non-diabetic Patients

INTRODUCTION

Diabetes mellitus is one of the major risk factors for coronary artery disease. Intravascular ultrasound (IVUS) imaging has an important role in the evaluation of atherosclerotic coronary artery disease. The aim of the study was to investigate the potential link between diabetes mellitus and plaque vulnerability in patients with coronary artery disease.

METHODS

In total, 26 patients with acute coronary syndrome (eight with diabetes mellitus) and 34 with stable angina pectoris (16 with diabetes mellitus) constituted the study population. Patients underwent IVUS ultrasound and virtual histology (VH)-IVUS imaging during routine diagnostic catheterization procedures. A total of 70 plaques in 60 patients were examined.

RESULTS

Patients with diabetes mellitus had a significantly greater percentage of fibrofatty components in the minimal lumen area (MLA) (17 ± 12 in diabetics; 12 ± 6 in non-diabetics; p=0.06). Thin-cap fibroatheromas were more frequent in patients with diabetes mellitus (72% versus 45%; p=0.012). There was a positive correlation between the presence of attenuated plaque and hemoglobin A1C (HbA1c) levels as well (7.09 ± 1.66 versus 6.02 ± 1.00; p=0.011). Patients with HbA1C ≥7.5% also had the highest prevalence of attenuated plaque.

CONCLUSION

As shown by VH-IVUS, the prevalence of vulnerable plaques in patients with diabetes mellitus was much higher than that in non-diabetic patients. The presence of attenuated plaque detected in grayscale intravascular ultrasonography was associated with high HbA1C levels in diabetic patients. Diabetes mellitus may cause cardiovascular vulnerability by changing the plaque morphology.

The clinical impact of serum 1,5-anhydro-D-glucitol levels on coronary artery calcification and adverse outcomes assessed by coronary optical coherence tomography in diabetic patients

Background

Serum 1,5-anhydro-D-glucitol (1,5-AG) is a novel biomarker for short-term glycemic status and postprandial hyperglycemia. The association between serum 1,5-AG levels and coronary artery calcification (CAC) through a quantitative assessment using optical coherence tomography (OCT) is unclear. We aimed to evaluate this association using OCT in patients with diabetes mellitus (DM).

Methods

From June 2016 to December 2019, we prospectively enrolled 256 patients who underwent OCT-guided percutaneous coronary intervention (PCI). Half of the patients had diabetes. Patients were followed up for a mean period of 1.8 ± 0.8 years (median: 2.2 years). The relative calcium index and relative lipid core index measured by quantitative OCT analysis were used to evaluate the intra-plaque calcium and lipid levels of culprit plaques. We also analyzed the correlation between serum 1,5-AG levels and long-term major adverse cardiovascular events.

Results

Serum 1,5-AG levels were significantly lower in diabetic patients than in non-diabetic patients (DM vs. non-DM: 55.6 ± 27.9 μg/mL vs. 63.7 ± 26.1 μg/mL, p = 0.016), and lower in fibrocalcified lesions than in fibrotic or fibrolipidic lesions (fibrocalcified vs. fibrotic or fibrolipidic: 42.8 ± 19.1 vs. 72.9 ± 25.2 or 66.4 ± 27.5 μg/mL, p < 0.001, respectively). In addition, we found a significant inverse correlation between serum 1,5-AG levels and relative calcium index (r = −0.729, p < 0.001). In multivariate Cox regression analysis, low serum 1,5-AG level was identified as an independent predictor for major adverse cardiovascular events in diabetic patients (p = 0.043), but not in non-diabetic patients (p = 0.748) after adjusting for age and sex.

Conclusion

This study revealed that low serum 1,5-AG levels were associated with an increased risk of CAC as assessed by OCT, especially in diabetic patients. Low serum 1,5-AG levels may predict future major adverse cardiovascular events in diabetic patients undergoing OCT-guided PCI.