Association of APOE genotype with carotid atherosclerosis in men and women: the Framingham Heart Study

The aim of this study was to determine the as- sociation between APOE genotype and carotid atherosclero- sis, defined as intimal-medial thickness (IMT) and stenosis, and to assess if other cardiovascular risk factors modify this association. A total of 1,315 men and 1,408 women from the Framingham Offspring Study underwent carotid ultrasound during examination cycle 6 and had complete data on APOE genotype. Three APOE genotype groups were defined: APOE2 (including E2 / E2 , E3/E2 genotypes), APOE3 ( E3 / E3 ), and APOE 4 (including E4/E3 , E4/E4 genotypes). Carotid IMT and the presence of carotid stenosis � 25% were deter- mined by ultrasonography. In women, the APOE2 group was associated with lower carotid IMT (0.67 vs. 0.73 mm) and lower prevalence of stenosis (odds ratio � 0.49; 95% confi- dence interval � 0.30-0.81) compared with the APOE3 group. In men, APOE genotype was not associated with ca- rotid IMT or stenosis in the whole group; however, diabetes modified the association between APOE genotype and ca- rotid IMT ( P for interaction � 0.044). Among men with dia- betes, the APOE4 group was associated with a higher inter- nal carotid artery IMT (1.22 mm) than the APOE3 group (0.90 mm) or the APOE2 group (0.84 mm). The E2 allele was associated with lower carotid atherosclerosis in women, and the E4 allele was associated with higher internal carotid