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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 50 out of 100. Genetics

Topic: Genetics and APOE

Cross-sectional positron emission tomography (PET) studies find that cognitively normal carriers of the apolipoprotein E (APOE) epsilon4 allele, a common Alzheimer's susceptibility gene, have abnormally low measurements of the cerebral metabolic rate for glucose (CMRgl) in the same regions as patients with Alzheimer's dementia. In this article, we characterize longitudinal CMRgl declines in cognitively normal epsilon4 heterozygotes, estimate the power of PET to test the efficacy of treatments to attenuate these declines in 2 years, and consider how this paradigm could be used to efficiently test the potential of candidate therapies for the prevention of Alzheimer's disease. We studied 10 cognitively normal epsilon4 heterozygotes and 15 epsilon4 noncarriers 50-63 years of age with a reported family history of Alzheimer's dementia before and after an interval of approximately 2 years. The epsilon4 heterozygotes had significant CMRgl declines in the vicinity of temporal, posterior cingulate, and prefrontal cortex, basal forebrain, parahippocampal gyrus, and thalamus, and these declines were significantly greater than those in the epsilon4 noncarriers. In testing candidate primary prevention therapies, we estimate that between 50 and 115 cognitively normal epsilon4 heterozygotes are needed per active and placebo treatment group to detect a 25% attenuation in these CMRgl declines with 80% power and P = 0.005 in 2 years. Assuming these CMRgl declines are related to the predisposition to Alzheimer's dementia, this study provides a paradigm for testing the potential of treatments to prevent the disorder without having to study thousands of research subjects or wait many years to determine whether or when treated individuals develop symptoms.

Key findings

Study details

How this study scored 50/100
How this study's score is builtJournal tier 7 of 10; Journal's citation record left out, no data; Study design 4 of 12; Strength of evidence 3 of 5; Peer-review validation 10 of 10; How recent 1 of 5; Sample size 0 of 4; Effect reported 0 of 3; Studied in people 0 of 3; Randomised / blinded 0 of 2; Times cited left out, no data; Citations per year left out, no data; Impact for its field and year left out, no data; Cited by studies here left out, no data; Still being cited left out, no data; Senior author's track record left out, no data; Institution's track record left out, no data; Multi-centre collaboration left out, no data; Indexed in PubMed 2 of 2; Free to read 2 of 2. 29 of the 58 points it could be judged on, which is 50 of 100. Total 50 of 100.29 of the 58 points we could judge = 50 of 100

Published in a peer-reviewed journal, and it is a snapshot of people at one point in time. Scored zero for sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 29 of the 58 points we could judge it on, which is 50 out of 100.

ComponentPointsWhy
Journal tier 7 / 10 Tier 3 — peer-reviewed journal (Proceedings of the National Academy of Sciences)
Journal's citation record — / 4 No journal record from OpenAlex — left out of this score
Study design 4 / 12 A snapshot of people at one point in time
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 2001 — older than 20 years, still counted
Sample size 0 / 4 Participant count not stated — scores zero (not stated in the record — scored 0)
Effect reported 0 / 3 No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people 0 / 3 Not stated whether this was studied in people — scores zero (not stated in the record — scored 0)
Randomised / blinded 0 / 2 No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited — / 7 No citation count (not found in OpenAlex) — left out of this score
Citations per year — / 5 No citation count or no year — left out of this score
Impact for its field and year — / 6 No field-weighted citation impact (OpenAlex has none yet) — left out of this score
Cited by studies here — / 6 Not yet checked against this library's citation graph — left out of this score
Still being cited — / 4 No yearly citation counts — left out of this score
Senior author's track record — / 4 Senior author's record not available — left out of this score
Institution's track record — / 3 No institution listed in OpenAlex — left out of this score
Multi-centre collaboration — / 3 Institutions not listed — left out of this score
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 11248079)
Free to read 2 / 2 Free to read
Points 29 / 58 Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 29 of the 58 points we could judge it on is 50 out of 100.
Total 50 / 100 —

What each of these 20 components measures, and what this score is not →

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Cite this study APA, Vancouver, BibTeX · download .bib or .ris

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APA 7th

Reiman, E. M., Caselli, R. J., Chen, K., Alexander, G. E., Bandy, D. J., & Frost, J. (2001). Declining brain activity in cognitively normal apolipoprotein E ɛ4 heterozygotes: A foundation for using positron emission tomography to efficiently test treatments to prevent Alzheimer's disease. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.061509598

Vancouver

Reiman EM, Caselli RJ, Chen K, Alexander GE, Bandy DJ, Frost J. Declining brain activity in cognitively normal apolipoprotein E ɛ4 heterozygotes: A foundation for using positron emission tomography to efficiently test treatments to prevent Alzheimer's disease. Proceedings of the National Academy of Sciences. 2001. doi:10.1073/pnas.061509598. PMID: 11248079.

BibTeX

@article{reiman2001-11248079,
  author  = {Reiman, Eric M. and Caselli, Richard J. and Chen, Kewei and Alexander, Gene E. and Bandy, Daniel J. and Frost, Jennifer},
  title   = {{Declining brain activity in cognitively normal apolipoprotein E ɛ4 heterozygotes: A foundation for using positron emission tomography to efficiently test treatments to prevent Alzheimer's disease}},
  journal = {Proceedings of the National Academy of Sciences},
  year    = {2001},
  doi     = {10.1073/pnas.061509598},
  pmid    = {11248079},
  url     = {https://doi.org/10.1073/pnas.061509598}
}

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