Do hypertension and diabetes mellitus influence the site of atherosclerotic plaques?

BACKGROUND: The concomitant occurrence of atherosclerotic plaques in carotid, coronary and peripheral vessels has been described in a number of studies. A few studies were, on the contrary, done for determining the role of hypertension and/or type 2 diabetes mellitus for the occurrence of the atherosclerotic plaques in different anatomical sites. Moreover these studies deal with atherosclerotic lesions that are generally considered, without differentiating their morphology as a function of the underlying disease, territory, and risk factors. Primary aim of this study is, thus, to verify whether the two most common causes for atherosclerotic disease, i.e., hypertension and type 2 diabetes mellitus, may influence the site of appearance of the atherosclerotic plaque. A second aim is to verify if the anatomical site of the plaque influences plaque morphology and vulnerability.

PATIENTS AND METHODS: A retrospective study of 244 patients affected with type 2 diabetes mellitus or hypertension was performed; 114 subjects were affected by moderate-severe and drugs-treated hypertension (Group A); 55 were affected by type 2 diabetes mellitus in treatment with oral antidiabetic drugs (Group B); 75 were diagnosed as affected by the association hypertension and diabetes (Group C). The inclusion criteria were: exhaustive images of the cardiovascular system (coronary angiography, colour Doppler ultrasound of lower limb arteries and carotid arteries, transthoracic Doppler echocardiography ) and a serum lipid profile (total serum cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides). Three different anatomical sites: carotid axis, ilio-femoral arteries and coronary district, were considered. In each site a plaque lesion-classification was performed to describe the morphology of the plaque.

RESULTS: In patients with hypertension, carotid district seems to be the preferential site of onset of atherosclerotic plaques even if a statistical significant association between the two conditions was not found. Statistical evaluation didn't show significant association between different risk factors and coronary district too. On the opposite, a significant association (p < 0.001) between diabetes and the presence of atherosclerotic plaques into lower limb district was found. A very significant association (p < 0.001) between type 2-diabetes and the presence of non-ulcerative plaques was found too.

CONCLUSIONS: Our study underlines the relationship between vessel plaques localization and concomitant risk factors for atherosclerosis and suggests a possible difference in plaque morphology and biological behaviour related to different anatomical site.