Apolipoprotein E and carotid artery atherosclerosis - The Rotterdam study

Background and Purpose-Carotid artery atherosclerosis is a strong predictor for future stroke. It is yet unclear whether the apolipoprotein E polymorp hism (APOE) is related to atherosclerosis in the carotid arteries. The aim of the present study was to investigate the role of APOE in carotid artery atherosclerosis. Methods-A population-based cross-sectional study was performed on 5401 subj ects. Atherosclerosis was noninvasively assessed by the common carotid arte ry intima-media wall thickness and the presence of plaques in the carotid a rteries. The relationship of the 6 APOE genotypes with these 2 indicators w as studied with linear and logistic regression analysis, respectively, with adjustments for age and sex. Results-Carriers of the E2E3 genotype had a thinner intima-media wall thick ness (mean difference, -0.02 nun; 95% CI, -0.03 to -0.01 mm) and fewer plaq ues (odds ratio for >3 plaques at 6 sites, 0.6; 95% CI, 0.4 to 0.8) than th e most common group, E3E3. The E4E4 group had slightly more atherosclerosis , but this was not statistically significant. Adjusting for the level of th e apolipoprotein E protein (apoE) in serum or total or HDL cholesterol did not essentially change these findings. Conclusions-Our results suggest that APOE*4 is not an important risk factor for carotid artery atherosclerosis. The inverse relationship of E2E3 with carotid artery atherosclerosis seems to be independent of serum apoE and to tal and HDL cholesterol levels. However, the low frequency, together with t he small effects, implies that any protective effect of E2E3 on carotid art ery atherosclerosis is limited.