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.

Plasma lipoprotein changes were evaluated in 65 type II patients undergoing sequential 4-week dietary treatments with: (I) standard low-lipid diet; (II) low-lipid diet with total replacement of animal proteins with textured soy proteins containing 6 % of lecithin (L-TVP); (III) standard low-lipid diet; (IV) low-lipid diet with a 50% substitution of animal proteins with L-TVP. Total cholesterolemia was significantly reduced in both periods of L-TVP administration: -18.6% during phase II (total replacement) and -13.2% during phase IV (partial replacement). High-density lipoprotein (HDL) cholesterol levels tended to increase during L-TVP administration. However, only patients in the mid- and low tertiles for HDL cholesterolemia showed a significant increase of HDL levels during L-TVP. This ‘normalizing’ activity of L-TVP on plasma lipoproteins, even when administered as a partial dietary substituent, may be of clinical interest for subgroups of patients at high vascular risk.