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Cerebrospinal fluid and plasma insulin levels in Alzheimer's disease: relationship to severity of dementia and apolipoprotein E genotype
Craft S, Peskind E, Schwartz MW, Schellenberg GD, Raskind M, Porte D.. Neurology, 1998-01-01
Topic: Amyloid, tau and blood-test diagnosis
Patients with Alzheimer's disease (AD) have elevations of fasting plasma insulin that are hypothesized to be associated with disrupted brain insulin metabolism. We examined paired fasted plasma and CSF insulin levels in 25 patients with AD and 14 healthy age-matched adults and determined whether insulin levels were related to severity of dementia and apolipoprotein E-epsilon4 homozygosity, a known genetic risk factor for AD. The AD patients had lower CSF insulin, higher plasma insulin, and a reduced CSF-to-plasma insulin ratio when compared with healthy adults. The differences were greater for patients with more advanced AD. Patients who were not apolipoprotein E-epsilon4 homozygotes had higher plasma insulin levels and reduced CSF-to-plasma ratios, whereas epsilon4 homozygotes with AD had normal values. Both plasma and CSF insulin levels are abnormal in AD, and there are metabolic differences among apolipoprotein E genotypes.
Key findings
- Patients with Alzheimer's disease (AD) have elevations of fasting plasma insulin that are hypothesized to be associated with disrupted brain insulin metabolism.
- The AD patients had lower CSF insulin, higher plasma insulin, and a reduced CSF-to-plasma insulin ratio when compared with healthy adults.
Why it matters
In 25 patients with Alzheimer's disease and 14 healthy adults, this study found lower CSF insulin, higher plasma insulin and a reduced CSF-to-plasma insulin ratio in patients, with greater differences in more advanced disease. It reports an association and metabolic differences by apolipoprotein E genotype, not a treatment, cure or prevention.
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Study details
- Participants25
- Evidence strengthLow
How this study scored 55/100
Published in a leading specialty journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Neurology) |
| Journal's citation record | 4 / 4 | Neurology: journal h-index 525 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1998 — older than 20 years, still counted |
| Sample size | 1 / 4 | 25 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 | 6 / 7 | Cited 562 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 18.7 citations a year over 30 year(s) since 1998 |
| Impact for its field and year | 3 / 6 | Cited 6.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 26 other studies in this library |
| Still being cited | 2 / 4 | Cited 38 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Daniel Porte: h-index 83 (OpenAlex, whole career) |
| Institution's track record | 3 / 3 | University of Washington: institution h-index 3,540 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9443474) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 55 / 100 | — |
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Read the original
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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. Check the citation against the original before you use it.
APA 7th
Craft, S., Peskind, E., Schwartz, M. W., Schellenberg, G. D., Raskind, M., & Porte, D. (1998). Cerebrospinal fluid and plasma insulin levels in Alzheimer's disease: relationship to severity of dementia and apolipoprotein E genotype. Neurology. https://doi.org/10.1212/wnl.50.1.164
Vancouver
Craft S, Peskind E, Schwartz MW, Schellenberg GD, Raskind M, Porte D. Cerebrospinal fluid and plasma insulin levels in Alzheimer's disease: relationship to severity of dementia and apolipoprotein E genotype. Neurology. 1998. doi:10.1212/wnl.50.1.164. PMID: 9443474.
BibTeX
@article{craft1998-9443474,
author = {Craft, S. and Peskind, E. and Schwartz, M. W. and Schellenberg, G. D. and Raskind, M. and Porte, D.},
title = {{Cerebrospinal fluid and plasma insulin levels in Alzheimer's disease: relationship to severity of dementia and apolipoprotein E genotype}},
journal = {Neurology},
year = {1998},
doi = {10.1212/wnl.50.1.164},
pmid = {9443474},
url = {https://doi.org/10.1212/wnl.50.1.164}
}
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