Role of hyperlipidemia in atherosclerotic plaque formation in the internal carotid artery

PURPOSE: The role of hyperlipidemia in atherosclerotic changes of the carotid artery is controversial. The aims of this retrospective study were to assess (1) the relationship between total serum cholesterol and triglyceride and the grade of internal carotid artery stenosis and (2) whether total serum cholesterol and triglyceride levels are independent risk factors for internal carotid artery atherosclerosis. METHODS: The files of 1,934 acute ischemic stroke patients were investigated retrospectively. The atherosclerotic involvement of the internal carotid artery was assessed via duplex sonography as percent of stenosis and was graded as follows: group 1, no plaque; group 2, <30% stenosis; group 3, 30-99% stenosis; and group 4, occlusion. RESULTS: The mean age of the patients was 66.9 +/- 12.8 years. Patients without any plaque had significantly lower cholesterol levels compared with those with any degree of internal carotid artery stenosis. Univariate analysis revealed that age (p < 0.001), sex (p < 0.001), hypertension (p < 0.05), cholesterol (p < 0.01), triglycerides(p < 0.05), and smoking (p < 0.001) were significant contributors to atherosclerosis. In the ordinal logistic regression model, age (p < 0.001), sex (p < 0.001), smoking(p < 0.001), and cholesterol (p < 0.05) remained independent predictors of internal carotid artery atherosclerosis. CONCLUSIONS: Total serum cholesterol level seems to be an independent risk factor of atherosclerosis in the carotid artery.