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The relationship between cerebral Alzheimer's disease pathology and odour identification in old age
Wilson RS, Arnold SE, Schneider JA, Tang Y, Bennett DA.. Journal of neurology, neurosurgery, and psychiatry, 2006-09-29
Topic: Amyloid, tau and blood-test diagnosis
Background Olfactory dysfunction is common in old age, but its basis is uncertain. Objective To test the hypothesis that difficulty in identifying odours in old age is related to the accumulation of Alzheimer's disease pathology. Methods As part of the Rush Memory and Aging Project, participants completed the 12-item Brief Smell Identification Test, a standard measure of odour identification. During a mean (standard deviation (SD)) of 2.2 (1.2) years of follow-up (range 0.2-4.9), 166 people died, with brain autopsies performed on 129 (77.7%) people and neuropathological examinations completed on 77 (mean (SD) age at death 87.5 (5.9) years; median postmortem interval 6.1 h). From a uniform postmortem examination of multiple brain regions, summary measures of plaque and tangle pathology were derived on the basis of silver staining, and those of amyloid beta burden, tangle density and Lewy bodies on the basis of immunohistochemistry. Results Odour identification performance ranged from 0 to 12 correct (mean (SD) 8.0 (2.6)). In analyses adjusted for age, sex and education, a composite measure of plaques and tangles accounted for >12% of the variation in odour identification. The association remained after controlling for dementia or semantic memory. Density of tau tangles was inversely related to odour identification. A similar effect for amyloid burden was attenuated after controlling for tangles. The association with odour identification was robust for tangles in the entorhinal cortex and CA1/subiculum area of the hippocampus, but not for tangles in other cortical sites. Lewy bodies, identified in 12.5%, were not related to odour identification, probably partly due to to their relative infrequency. Conclusion The results suggest that difficulty in identifying familiar odours in old age is partly due to the accumulation of neurofibrillar pathology in central olfactory regions.
Key findings
- Results Odour identification performance ranged from 0 to 12 correct (mean (SD) 8.0 (2.6)).
- Conclusion The results suggest that difficulty in identifying familiar odours in old age is partly due to the accumulation of neurofibrillar pathology in central olfactory regions.
Why it matters
In this autopsy study, difficulty identifying familiar odors in old age was partly related to the buildup of tau tangles and other Alzheimer's disease pathology in the brain. This links a simple smell test to brain pathology but does not test any treatment, cure or prevention.
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Study details
- Participants166
- Effect size77.7%; 12.5%
- Evidence strengthLow
How this study scored 56/100
Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Journal of neurology, neurosurgery, and psychiatry) |
| Journal's citation record | 3 / 4 | Journal of Neurology Neurosurgery & Psychiatry: journal h-index 336 (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 | 2007 — within 20 year(s) of the newest study here |
| Sample size | 2 / 4 | 166 participants |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| 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 306 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 14.6 citations a year over 21 year(s) since 2007 |
| Impact for its field and year | 3 / 6 | Cited 4.2× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 17 other studies in this library |
| Still being cited | 3 / 4 | Cited 68 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author David Alan Bennett: h-index 197 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Pennsylvania: institution h-index 1,859 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 17012338) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 56 / 100 | — |
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Read the original
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
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
Wilson, R. S., Arnold, S. E., Schneider, J. A., Tang, Y., & Bennett, D. A. (2007). The relationship between cerebral Alzheimer's disease pathology and odour identification in old age. Journal of neurology, neurosurgery, and psychiatry. https://doi.org/10.1136/jnnp.2006.099721
Vancouver
Wilson RS, Arnold SE, Schneider JA, Tang Y, Bennett DA. The relationship between cerebral Alzheimer's disease pathology and odour identification in old age. Journal of neurology, neurosurgery, and psychiatry. 2007. doi:10.1136/jnnp.2006.099721. PMID: 17012338.
BibTeX
@article{wilson2007-17012338,
author = {Wilson, R. S. and Arnold, S. E. and Schneider, J. A. and Tang, Y. and Bennett, D. A.},
title = {{The relationship between cerebral Alzheimer's disease pathology and odour identification in old age}},
journal = {Journal of neurology, neurosurgery, and psychiatry},
year = {2007},
doi = {10.1136/jnnp.2006.099721},
pmid = {17012338},
url = {https://doi.org/10.1136/jnnp.2006.099721}
}
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