Increased echolucency of carotid plaques in patients with type 2 diabetes

Background and Purpose - Diabetes is associated with the presence of moderate to large atherosclerotic carotid plaques. Previous carotid ultrasound studies have associated plaques with low echogenicity with a higher risk of cerebrovascular events. The aim of this study was to evaluate whether patients with type 2 diabetes have different plaque echogenicity than do nondiabetic subjects. Methods - Forty-seven type 2 diabetic and 51 nondiabetic subjects with a carotid plaque in the right artery were included in this study. All patients were born in 1935 to 1936 and were participants in a population-based study. Carotid ultrasonography was performed and the risk factors for cardiovascular disease were determined. Plaque echogenicity was assessed quantitatively on B-mode ultrasound images by standardized gray-scale median values. Results - Gray-scale median values were significantly lower, indicating more echolucent plaques, in patients with type 2 diabetes compared with nondiabetics (37.0 +/- 14.8 vs 45.5 +/- 15.4, P=0.007). Of the other risk factors studied, only triglycerides were significantly associated with the echogenicity of the plaque. Conclusions - Patients with type 2 diabetes have more echolucent plaques compared with nondiabetic subjects. This might be associated with the higher risk of cardiovascular events among diabetics.