Carotid intima media thickness (CIMT) has been used as a risk stratification tool for coronary artery disease (CAD). However, there is insufficient prospective data regarding carotid plaque (CP) and severity of CAC in asymptomatic diabetic subjects.Aim
Our aim was to determine if CIMT and presence of CP were predictors of prevalence and severity of CAC.Methods
One hundred and eight (n = 108) diabetic patientsrecruited for the PROCEED study (Progression of Coronary Atherosclerosis in Asymptomatic Diabetic Subjects – Evaluation of the role of CT Coronary Angiography and bio-markers of Endothelial Dysfunction and Vascular Inflammation) a prospective study in asymptomatic Type II diabetic subjects, evaluating the progression of atherosclerosis, underwent both carotid ultrasound and CAC scan. Measures of carotid atherosclerosis include CIMT and presence of carotid plaque. Coronary calcium scan was done by dual source multi slice scanner ((Siemens Medical Systems, Forchheim, Germany) and carotid ultrasound was performed using 9–12 MHz linear transducer (GE Vivid E9).Results
The mean age of the study population was 61.3 + 8.7 years and Body Mass Index (BMI) 31.1 + 6.8. There were 65 (60.2%) males, 9 (8.3%)with h/o current smoking, 87(80%) with hypertension, 71 (65.7%) with hyperlipidaemia, 50 (46%) with micro vascular disease and 15 (13.9%) with a h/o premature ischaemic heart disease (IHD) .Results
Mean CIMT was 0.82 ± 0.17 mm and CP was noted in 43(40%) patients. Mean CIMT did not differ significantly in patients with micro-vascular disease (MVD) as compared to those without (0.85 ± 0.18 mm vs 0.80 ± 0.17 mm). 32 (30%) patients had a CAC score of zero.76 (70%) had CAC >0, of which, 53(49%) had CAC score 1–400 and 23(21%) had a CAC score > 400. Association between CAC and CP was stronger on univariate (p = 0.002) and borderline on multivariate (p = 0.05) regression analysis. A significant association between prevalence of carotid plaque and severe CAC (>400Au) was noted in a Chi square analysis (p 0.019), Odds Ratio of 3.81 (95% CI of 1.44–10.06) whereas correlation between CAC and IMT was poor(r = 00.03) on bivariate analysis.Conclusion
Presence of CP was independently associated with severity of CAC whereas CIMT was not, even in this high risk diabetic population. Carotid plaque evaluation may have important clinical implication by identifyingsub group of high risk population in asymptomatic diabetes.