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Alzheimer's disease in Down's syndrome: clinicopathologic studies
Wisniewski KE, Dalton AJ, McLachlan C, Wen GY, Wisniewski HM.. Neurology, 1985-07-01
Topic: Amyloid, tau and blood-test diagnosis
Clinical and neuropathologic evidence points to the development of Alzheimer's disease (AD) in seven Down's syndrome patients above age 40. Dementia was observed in these patients over periods of 2.5 to 9.2 years. The first clinical sign of AD, visual memory loss, was succeeded by impaired learning capacity and decreased occupational and social functioning, and culminated in seizures and urinary incontinence. The morphometric observations of the brains of these seven patients with AD showed that the numbers of plaques and tangles exceeded 20 per 1.5 X 10(6) microns2 area, in both the prefrontal and hippocampal cortices. Plaques and tangles were also evident in the basal ganglia, thalamus, hypothalamus, and midbrain. In addition, we found that four of the seven brains showed small strokes, and five of the seven amyloid angiopathy. This study also indicates that by longitudinal neuropsychological evaluations and lab tests, which exclude other causes of dementia, the diagnosis of AD can be made even in severely and profoundly retarded patients.
Key findings
- The morphometric observations of the brains of these seven patients with AD showed that the numbers of plaques and tangles exceeded 20 per 1.5 X 10(6) microns2 area, in both the prefrontal and hippocampal cortices.
- In addition, we found that four of the seven brains showed small strokes, and five of the seven amyloid angiopathy.
- This study also indicates that by longitudinal neuropsychological evaluations and lab tests, which exclude other causes of dementia, the diagnosis of AD can be made even in severely and profoundly retarded patients.
Why it matters
In seven adults with Down syndrome over age 40, followed for 2.5 to 9.2 years, dementia began with loss of visual memory, then problems with learning and daily and social functioning, and ended with seizures and urinary incontinence. After death, every brain had many Alzheimer's plaques and tangles; four also showed small strokes and five showed amyloid deposits in blood-vessel walls. The authors conclude that repeated testing over time, plus lab tests that rule out other causes, can diagnose Alzheimer's even in people with severe or profound intellectual disability. This was a series of seven cases with no comparison group, and it did not test any treatment.
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Study details
- Study designlongitudinal study
- Evidence strengthModerate
How this study scored 61/100
Published in a leading specialty journal, and it is a longitudinal study following the same people over time. Scored zero for sample size, effect reported, studied in people 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 | 7 / 12 | A longitudinal study following the same people over 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 | 1985 — 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 | 6 / 7 | Cited 415 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 9.7 citations a year over 43 year(s) since 1985 |
| Impact for its field and year | 4 / 6 | Cited 14.6× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 39 other studies in this library |
| Still being cited | 2 / 4 | Cited 31 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Henryk M. Wı́sniewski: h-index 76 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Toronto: institution h-index 1,923 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 3159974) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 61 / 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
Wisniewski, K. E., Dalton, A. J., McLachlan, C., Wen, G. Y., & Wisniewski, H. M. (1985). Alzheimer's disease in Down's syndrome: clinicopathologic studies. Neurology. https://doi.org/10.1212/wnl.35.7.957
Vancouver
Wisniewski KE, Dalton AJ, McLachlan C, Wen GY, Wisniewski HM. Alzheimer's disease in Down's syndrome: clinicopathologic studies. Neurology. 1985. doi:10.1212/wnl.35.7.957. PMID: 3159974.
BibTeX
@article{wisniewski1985-3159974,
author = {Wisniewski, K. E. and Dalton, A. J. and McLachlan, C. and Wen, G. Y. and Wisniewski, H. M.},
title = {{Alzheimer's disease in Down's syndrome: clinicopathologic studies}},
journal = {Neurology},
year = {1985},
doi = {10.1212/wnl.35.7.957},
pmid = {3159974},
url = {https://doi.org/10.1212/wnl.35.7.957}
}
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