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Parkinson disease neuropathology: later-developing dementia and loss of the levodopa response
Apaydin H, Ahlskog JE, Parisi JE, Boeve BF, Dickson DW.. Archives of neurology, 2002-01-01
Topic: Brain proteins, microglia and lab models
Objective To investigate the neuropathologic substrate for dementia occurring late in Parkinson disease (PD). Design We identified 13 patients with a clinical diagnosis of PD who experienced dementia at least 4 years after parkinsonism onset (mean, 10.5 years) and subsequently underwent postmortem examination. Despite levodopa therapy, 9 patients later became severely impaired and nonambulatory, requiring total or near-total care; this included 4 patients treated with 1200 mg/d or more of levodopa (with carbidopa), which was consistent with loss of the levodopa response.
Key findings
- Design We identified 13 patients with a clinical diagnosis of PD who experienced dementia at least 4 years after parkinsonism onset (mean, 10.5 years) and subsequently underwent postmortem examination.
- Despite levodopa therapy, 9 patients later became severely impaired and nonambulatory, requiring total or near-total care; this included 4 patients treated with 1200 mg/d or more of levodopa (with carbidopa), which was consistent with loss of the levodopa response.
- These 13 patients were compared with 9 patients clinically diagnosed as having PD, but without dementia, who had undergone autopsies.
- Results Twelve of 13 PD patients with dementia had findings of diffuse or transitional Lewy body disease as the primary pathologic substrate for dementia; 1 had progressive supranuclear palsy.
Why it matters
This study examined the brain pathology of 13 patients with Parkinson disease who developed dementia at least four years after parkinsonism onset, including some who lost the levodopa response. It describes neuropathologic findings and does not test a treatment for Alzheimer's disease.
Study details
- Participants13
- Evidence strengthLow
How this study scored 53/100
Published in a peer-reviewed journal. Scored zero for study design, 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 | 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 | 2002 — older than 20 years, still counted |
| Sample size | 1 / 4 | 13 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 401 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 15.4 citations a year over 26 year(s) since 2002 |
| Impact for its field and year | 5 / 6 | Cited 21.9× 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 | 1 / 4 | Cited 11 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Dennis W. Dickson: h-index 218 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Mayo Clinic: institution h-index 1,606 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 11790237) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 53 / 100 | — |
What each of these 20 components measures, and what this score is not →
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
Apaydin, H., Ahlskog, J. E., Parisi, J. E., Boeve, B. F., & Dickson, D. W. (2002). Parkinson disease neuropathology: later-developing dementia and loss of the levodopa response. Archives of neurology. https://doi.org/10.1001/archneur.59.1.102
Vancouver
Apaydin H, Ahlskog JE, Parisi JE, Boeve BF, Dickson DW. Parkinson disease neuropathology: later-developing dementia and loss of the levodopa response. Archives of neurology. 2002. doi:10.1001/archneur.59.1.102. PMID: 11790237.
BibTeX
@article{apaydin2002-11790237,
author = {Apaydin, H. and Ahlskog, J. E. and Parisi, J. E. and Boeve, B. F. and Dickson, D. W.},
title = {{Parkinson disease neuropathology: later-developing dementia and loss of the levodopa response}},
journal = {Archives of neurology},
year = {2002},
doi = {10.1001/archneur.59.1.102},
pmid = {11790237},
url = {https://doi.org/10.1001/archneur.59.1.102}
}
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