Carotid Intima-media Thickness through the Continuum of Dysglycemia in North Indian Population

Abstract

Background: The carotid intima-media thickness (CIMT) is uniformly regarded as a consistent noninvasive marker for subclinical atherosclerosis and is widely accepted for assessment of cardiovascular risk in high-risk individuals including diabetes. Objectives: The present study was conducted to estimate the CIMT in prediabetes, new-onset type 2 diabetes mellitus (T2DM), and those with disease of at least 5-year duration to analyze its relationship to this common metabolic disorder and other risk factors. Materials and Methods: This was a cross-sectional hospital-based study conducted on 75 patients, 25 in each Group A (with T2DM of more than 5-year duration), Group B (new-onset T2DM), and Group C (prediabetes). IMT was measured in common carotid artery (CCA) bilaterally using high-resolution B-mode ultrasound. Continuous variables in the three groups were evaluated by analysis of variance, and CIMT was correlated with glycosylated hemoglobin (HbA1c) and lipid profile by Pearson’s correlation. Results: The mean CIMT in the right CCA was 0.67 + 0.12 mm, 0.58 + 0.07 mm, and 0.53 + 0.07 mm and in the left CCA was 0.65 + 0.10 mm, 0.58 + 0.06 mm, and 0.54 + 0.07 mm in Groups A, B, and C, respectively. A statistically significant difference was observed between Group A and Group B as well as between Group A and Group C (P < 0.05). Patients with diabetes (DM) who had disease of over 5-year duration and relatively poor control of blood glucose (high HbA1c), and dyslipidemia, had significantly higher CIMT values than those with new-onset DM as well as prediabetes. Conclusion: All the three subgroups of dysglycemic individuals had higher CIMT as compared to historical data from healthy Asian Indian population. The CIMT values increased along the temporal continuum of hyperglycemia, being the lowest in individuals with prediabetes to the highest values in DM of at least 5-year duration. This indicates that subclinical atherosclerosis has an onset early in DM and CIMT has a linear relationship with the progression of hyperglycemia.