Correlation of glycosylated haemoglobin (HbA1c) levels with subclinical atherosclerosis in patients with type 2 diabetes mellitus


Background: The most common cause of mortality in people with diabetes is cardiovascular disease. The relation between glycosylated hemoglobin (HbA1c), a marker of glycemic control, and the development of subclinical atherosclerosis is debated. An acceptable indicator of subclinical atherosclerosis is the use of ultrasound to measure carotid intima-media thickness (CIMT).Objective: To conduct a cross-sectional study exploring the correlation between HbA1c and subclinical atherosclerosis as reflected by the carotid intima-media thickness in patients with type 2 diabetes that had no history of an atherosclerotic cardiovascular disease (ischemic heart disease or cerebrovascular accident).Methods: A total of 71, type 2 diabetic patients participated in this study. Demographic, anthropometric and laboratory measures of the participants were collected. CIMT values were measured by using a high-resolution ultrasound. Increased CIMT values were accepted as >0.9 mm. Participants were categorized into two groups according to CIMT values: a normal CIMT value of ≤ 0.9 mm group, and a high CIMT value of > 0.9 mm group. HbA1c and other collected variables were compared between normal and increased CIMT groups. Furthermore, subgroup analysis was carried out for patients with poor glycemic control (HbA1c>9%).Results: The mean CIMT was 1.048 ± 0.14 mm, and approximately 79% of the included population had increased CIMT (> 0.9 mm). 49% of participants were poorly controlled (HbA1c > 9%) and 92% of those with poor glycaemic control had increased CIMT. Correlation analysis of data belonging to participants with poor glycaemic control (HbA1c > 9%) showed a significant correlation between HbA1c levels and CIMT, with a correlation coefficient of 0.409 (P = 0.015). In addition, a significant correlation was found in our initial analysis between CIMT and age, with a value of 0.359 (P = 0.002).Conclusion: This study revealed that HbA1c levels in patients with poor glycemic control are positively correlated with increased CIMT measures, which is an indicator of subclinical atherosclerosis (SCA). Moreover, increased age is found to be a predictor factor for the development of SCA and, consequently, adverse macrovascular outcomes in patients with T2D.


T2DM, CIMT and HbA1c