Polymorphism of the Apolipoprotein E Gene and Early Carotid Atherosclerosis Defined by Ultrasonography in Asymptomatic Adults

Abstract

Clinical and autoptical studies have suggested a predisposing role of the allele E4 of apolipoprotein E (apoE) in the development of atherosclerosis and cardiovascular disease. To investigate the possible contribution of apoE allele polymorphism to the carotid intima-media thickness (IMT) as assessed by ultrasound, we studied 260 asymptomatic nondiabetic subjects (121 men, 139 women; mean +/- SD age, 53 +/- 7 years), randomly selected from the population register of the inhabitants of Trieste, Italy. B-mode ultrasound was used to quantify the maximum IMT at 12 sites on the near and far wall of the common, bifurcation, and internal carotid arteries. ApoE genotypes were determined from amplified apoE sequences by restriction isotyping. The frequencies of E2, E3, and E4 alleles were 0.073, 0.827, and 0.100, respectively. As expected, subjects with E4 allele had the highest levels of total serum cholesterol and LDL cholesterol, subjects with E2 allele had the lowest levels, and those with E3 genotype had intermediate levels. The echographic measurements of carotid IMT showed increasing values from E2 to E4 carriers. After adjustment for total and LDL cholesterol serum levels, triglycerides, ratio of LDL to HDL cholesterol, age, sex, and body mass index, ANCOVA showed that the common carotid IMT was significantly greater (P = .029) in subjects with E4 allele compared with E3 carriers. Our data confirm the influence of apoE4 on cholesterol levels and clearly show that apoE genotype affects carotid atherosclerosis in its early stages in middle-aged asymptomatic subjects.

Risk factor–gene interaction in carotid atherosclerosis: effect of gene polymorphisms of renin-angiotensin system

“…In an earlier study, an association between the E4 allele and carotid atherosclerosis was demonstrated in middle-aged asymptomatic subjects from a general population (Cattin et al 1997). However, conflicting results have also been reported regarding the association between apoE4 and carotid atherosclerosis .…”

“…Because isoforms of apolipoprotein E (apoE) have also been shown to be related to cardiovascular disease and atherosclerosis (Cattin et al 1997), we also investigated the association of apoE genotype with carotid IMT, as an independent genetic factor of the RAS.…”

Assessment of Subclinical Atherosclerosis Using Computed Tomography Calcium Scores in Patients with Familial and Nonfamilial Hypercholesterolemia

“…Even after adjustment for traditional risk factors, including LDL-C levels, an association between FH gene mutations and the prevalence of CAD was found 21) . It is possible that the genes responsible for hyperlipidemia can act upon atherogenesis not only by an evident increase in the serum lipid profile but also by other gene-gene and gene-environmental interactions 22) . Although the nature of the FH molecular defect has a significant impact on the severity of hypercholesterolemia to date, there is no convincing evidence that molecular diagnosis has any important therapeutic implications.…”

Vitamin E 80th Anniversary: A Double Life, Not Only Fighting Radicals

“…When selecting a population for an intervention study, the genotype of individuals has been constantly ignored. Apo E genotype may in uence carotid atherosclerosis in its early stages; in particular, the E4 allele favours the disease (83,84). Consequently, in order to see protective effects against atherosclerosis, vitamin E supplementation should start as early as possible, should be maintained for longer periods, and should be associated with vitamin C. In the selection of the population to study, Apo E genotype, gender, and vitamin E status should be closely taken into consideration.…”