Association between apolipoprotein E genotype and Alzheimer disease in African American subjects
Graff-Radford NR, Green RC, Go RC, Hutton ML, Edeki T, Bachman D, Adamson JL, Griffith P et al.. Archives of neurology, 2002-04-01
Topic: Amyloid, tau and blood-test diagnosis
Background The association between Alzheimer disease (AD) and genotypes at the apolipoprotein E (APOE) locus has been confirmed in numerous populations worldwide, but appears to be inconsistent in African American subjects. Objective To investigate the association between APOE genotypes and AD in elderly African American subjects. Design Clinic-based, multicenter case-control study and a family study. Participants A total of 338 African American probands meeting criteria for probable or definite AD, 301 cognitively healthy, elderly unrelated control subjects (spouses and community volunteers), and 108 siblings of 88 AD probands. Main outcome measures Odds of AD according to APOE genotype. Results Compared with individuals with the APOEepsilon3/epsilon3, the odds of having AD were significantly increased among those with 1 or more copies of the epsilon4 allele; the odds ratio (OR) for the epsilon3/epsilon4 genotype was 2.6 (95% confidence interval [CI], 1.8-3.7), and the OR for the epsilon4/epsilon4 genotype was 10.5 (95% CI, 5.1-21.8). These risks decreased substantially after 68 years of age. The risk for AD was lower among individuals with the epsilon2/epsilon3 genotype (OR, 0.41; 95% CI, 0.22-0.79). The patterns of association were similar in men and women. These results obtained from comparisons of unrelated AD patients and controls were bolstered by results of analysis of family data that showed preferential transmission of the epsilon4 allele to demented siblings (P Conclusions The presence of 1 or 2 epsilon4 alleles is a determinant of AD risk in African American subjects. The age-related risk for decline associated with the epsilon4 allele and the apparent protective effect of the epsilon2 allele are similar to patterns observed in white subjects.
Key findings
- Results Compared with individuals with the APOEepsilon3/epsilon3, the odds of having AD were significantly increased among those with 1 or more copies of the epsilon4 allele; the odds ratio (OR) for the epsilon3/epsilon4 genotype was 2.6 (95% confidence interval [CI], 1.8-3.7), and the OR for the epsilon4/epsilon4 genotype was 10.5 (95% CI, 5.1-21.8).
- These results obtained from comparisons of unrelated AD patients and controls were bolstered by results of analysis of family data that showed preferential transmission of the epsilon4 allele to demented siblings (P<<.001) and of the epsilon2 allele to nondemented siblings (P=.005).
- The age-related risk for decline associated with the epsilon4 allele and the apparent protective effect of the epsilon2 allele are similar to patterns observed in white subjects.
Why it matters
Among African American participants, carrying one or more copies of the APOE ε4 allele was linked to higher odds of Alzheimer disease, while the ε2/ε3 genotype was linked to lower odds. These risks decreased substantially after age 68, and the findings are about genetic association, not a treatment or cure.
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Study details
- Study designcase-control study
- Participants338
- Evidence strengthModerate
How this study scored 58/100
Published in a peer-reviewed journal, and it is a case-control study. Scored zero for effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Archives of neurology) |
| Journal's citation record | 3 / 4 | Archives of Neurology: journal h-index 353 (OpenAlex, 2026-10-29) |
| Study design | 6 / 12 | A case-control study |
| Strength of evidence | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2002 — older than 20 years, still counted |
| Sample size | 2 / 4 | 338 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 113 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 4.3 citations a year over 26 year(s) since 2002 |
| Impact for its field and year | 3 / 6 | Cited 3.9× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 12 other studies in this library |
| Still being cited | 1 / 4 | Cited 4 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Lindsay A. Farrer: h-index 119 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Boston University: institution h-index 1,456 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 6 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 11939894) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 58 / 100 | — |
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Read the original
May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Graff-Radford, N. R., Green, R. C., Go, R. C., Hutton, M. L., Edeki, T., Bachman, D., et al. (2002). Association between apolipoprotein E genotype and Alzheimer disease in African American subjects. Archives of neurology. https://doi.org/10.1001/archneur.59.4.594
Vancouver
Graff-Radford NR, Green RC, Go RC, Hutton ML, Edeki T, Bachman D, et al. Association between apolipoprotein E genotype and Alzheimer disease in African American subjects. Archives of neurology. 2002. doi:10.1001/archneur.59.4.594. PMID: 11939894.
BibTeX
@article{graffradford2002-11939894,
author = {Graff-Radford, N. R. and Green, R. C. and Go, R. C. and Hutton, M. L. and Edeki, T. and Bachman, D. and Adamson, J. L. and Griffith, P. and others},
title = {{Association between apolipoprotein E genotype and Alzheimer disease in African American subjects}},
journal = {Archives of neurology},
year = {2002},
doi = {10.1001/archneur.59.4.594},
pmid = {11939894},
url = {https://doi.org/10.1001/archneur.59.4.594}
}
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