Non-invasively Measured Carotid Artery Intima-Medial Thickness May Be a More Useful Marker of Coronary Artery Disease in Diabetic than Non-Diabetic Patients

Carotid intima-medial thickness has long been proposed as a surrogate marker of atherosclerotic vascular disease in other vascular beds, most notably the coronary arteries with its practical implications. This observational study aimed at exploring the relationship of a hypothetical stronger relationship of carotid intima-medial thickness with coronary artery disease in diabetic patients than non-diabetic counterparts. Thirty diabetic patients and 74 non-diabetic patients who were referred for coronary angiogram in the Departments of Cardiology Bangabandhu Sheikh Mujib Medical University and Combined Military Hospital, Dhaka Cantonment, Bangladesh from January, 2002 and December, 2003 were studied. Carotid ultrasound was done to determine intima-medial thickness and coronary angiogram to detect coronary artery lesions. Background demographic data and cardiovascular risk factors were determined. Of the 30 diabetic patients 24 subjects had CAD. Twenty two of these 24 patients showed increased carotid IMT. None of the patients without CAD had shown carotid artery intima-medial thickening (sensitivity 91% specificity 100%). In contrast, in the non-diabetic group 44 patients out of 63 with CAD showed increased carotid artery IMT. Four of the 11 non-diabetic patients without CAD showed positive carotid ultrasound study results (sensitivity 70%, specificity 63%). This study showed a strong association of coronary artery disease with carotid intima-medial thickness in diabetic patients compared to non-diabetic subjects. This finding may be applicable for Bangladeshi diabetic population. This surrogate marker of coronary artery disease can be useful in the management of diabetes as regards their prevention of coronary artery disease. The practical and clinical implications of these findings might be the pioneer study in diabetic subjects and need to be further determined in a larger community level study.