Major determinants of the carotid intima-media thickness in type 2 diabetic patients: age and body mass index

Abstract

The present study has been designed to quantify and compare right and left carotid intima-media thicknesses (IMT) in type 2 diabetics and healthy controls. It was also intended to investigate the effects of various risk factors on the carotid IMT in these subjects. A total of 122 subjects; 70 patients with type 2 diabetes and 52 non-diabetic subjects as controls, were recruited for the study. Right and left common carotid artery stiffness indices were assessed with ultrasonography in both groups. Age, body mass index (BMI), duration of diabetes, cigarette smoking, lipid profile including lipoprotein a, Chlamydia pneumonia seropositivity, glycemic indices, fasting insulin levels, serum fibrinogen levels and presence of hypertension, coronary artery disease, degenerative complications of diabetes mellitus were all assessed in order to define their role as determinants of carotid artery IMT. The difference between the groups regarding mean carotid IMT was statistically significant for the left carotid arteries (p = 0.028) and borderline significance was found for the right carotid arteries (p = 0.055). Age has a very strong association with carotid IMT in diabetic patients (p < 0.0001) with univariate analysis. According to the results of multivariate analysis, age and BMI were found to be the most important independent determinants of carotid IMT for both sides. When age was excluded from the model, BMI and coronary artery disease were found to have strong association with IMT on the right (p = 0.0036 and 0.0249) and BMI was the only significant determinant for the left side (p = 0.0025). This study shows that carotid IMT is greater in diabetic subjects compared with healthy controls. For the diabetic subjects, age, BMI and presence of coronary heart disease have a strong influence on the atherosclerotic process of the carotid arteries.