title: Relative risk of Alzheimer disease and age-at-onset distributions, based on APOE genotypes among elderly African Americans, Caucasians, and Hispanics in New York City.
abstract: Apolipoprotein-E epsilon 4 (APOE-epsilon 4) has been consistently associated with Alzheimer disease (AD) and may be responsible for an earlier age at onset. We have previously reported a diminished association between APOE-epsilon 4 and AD in African Americans. Using a new method, which allows inclusion of censored information, we compared relative risks by APOE genotypes in an expanded collection of cases and controls from three ethnic groups in a New York community. The relative risk for AD associated with APOE-epsilon 4 homozygosity was increased in all ethnic groups (African American relative risk [RR]=3.0; 95% confidence interval [CI]=1.5-5.9; Caucasian RR=7.3, 95% CI=2.5-21.6; and Hispanic RR=2.5, 95% CI=1.1-5.7), compared with those with APOE-epsilon 3/epsilon 3 genotypes. The risk was also increased for APOE-epsilon 4 heterozygous Caucasians (RR=2.9, 95% CI=1.7-5.1) and Hispanics (RR=1.6, 95% CI=1.1-2.3), but not for African Americans (RR=0.6, 95% Ci=0.4-0.9). The age distribution of the proportion of Caucasians and Hispanics without AD was consistently lower for APOE-epsilon 4 homozygous and APOE-epsilon 4 heterozygous individuals than for those with other APOE genotypes. In African Americans this relationship was observed only in APOE-epsilon 4 homozygotes. These results confirm that APOE genotypes influence the RR of AD in Caucasians and Hispanics. Differences in risk among APOE-epsilon 4 heterozygote African Americans suggest that other genetic or environmental factors may modify the effect of APOE-epsilon 4 in some populations.
authors.affiliation: The Gertrude H. Sergievsky Center, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: M X
authors.initials: MX
authors.lastname: Tang
authors.forename: G
authors.initials: G
authors.lastname: Maestre
authors.forename: W Y
authors.initials: WY
authors.lastname: Tsai
authors.forename: X H
authors.initials: XH
authors.lastname: Liu
authors.forename: L
authors.initials: L
authors.lastname: Feng
authors.forename: W Y
authors.initials: WY
authors.lastname: Chung
authors.forename: M
authors.initials: M
authors.lastname: Chun
authors.forename: P
authors.initials: P
authors.lastname: Schofield
authors.forename: Y
authors.initials: Y
authors.lastname: Stern
authors.forename: B
authors.initials: B
authors.lastname: Tycko
authors.forename: R
authors.initials: R
authors.lastname: Mayeux
mesh_terms: D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000208:ethnology / Q000235:genetics*; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics*; D044383:Black People / Q000235:genetics; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006630:Hispanic or Latino / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D012044:Regression Analysis; D012306:Risk; D044465:White People / Q000235:genetics; D001741:Black or African American
chemical_list: D053327:Apolipoprotein E4; D001057:Apolipoproteins E