Apo-lipoprotein profile in subjects with extracranial carotid atherosclerosis

Relationships between plasma lipoproteins and cerebrovascular atherosclerosis are not completely clear. In a group of asymptomatic nondiabetic normolipidemic subjects, plasma lipid and apolipoprotein profiles have been related to extracranial carotid atherosclerotic lesions, as assessed by B-mode ultrasonography and independent relations between lipid and clinical parameters and carotid atherosclerosis have been evaluated. We have found that subjects with atherosclerotic lesions (both intimal thickening or plaque) had TG levels and CHO/HDL-C and LDL-C/HDL-C ratios significantly higher and HDL-C and apo A-I levels significantly lower in comparison with subjects with normal arteries. When patients were divided according to the lesions of carotid arteries subjects with atherosclerotic plaque presented HDL-C and apo A-I levels significantly reduced and TG and apo B levels and CHO/HDL-C and LDL-C/HDL-C ratios significantly increased in comparison with subjects with normal arteries, and HDL-C levels reduced and CHO/HDL-C and LDL-C/HDL-C ratios increased in comparison with subjects with intimal thickening. Patients with intimal thickening and normal subjects differed for HDL-C and TG levels and CHO/HDL-C and LDL-C/HDL-C ratios. At multivariate analysis HDL-C levels (negatively), age, hypertension and cigarette smoking (positively) resulted independently associated with cerebrovascular atherosclerosis. Our data seem to show that, although several lipid and apoprotein abnormalities are able to initiate the atherosclerotic process in extracranial carotid district, probably the presence of low HDL-cholesterol levels is an important condition to determine the further worsening of the lesions.