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Cognitive status correlates with neuropathologic stage in Parkinson disease
Braak H, Rüb U, Jansen Steur EN, Del Tredici K, de Vos RA.. Neurology, 2005-04-01
Topic: Risk, prevention and care in population studies
Objective To study the association of cognitive status with the stages of a published neuropathologic staging procedure for sporadic Parkinson disease (PD) in a cohort of 88 patients with PD from a single neurologic unit. None had received the clinical diagnosis of dementia with Lewy bodies (DLB). Methods The authors assessed Lewy neurites/bodies (LNs/LBs) immunoreactive for alpha-synuclein semiquantitatively in sections from 18 brain regions. In silver-stained sections and sections immunostained for tau and beta-amyloid protein, the authors semiquantitatively evaluated comorbidities potentially contributing to cognitive decline, e.g., Alzheimer disease (AD), argyrophilic grain disease (AGD), and cerebral vascular disease. The authors analyzed four Mini-Mental State Examination (MMSE) subgroups ranging from marginally impaired cognition to severe dementia using nonparametric tests. Results It was possible to assign all patients to one of the PD stages. MMSE scores correlated with neuropathologic stages (p Conclusions The decrease in median Mini-Mental State Examination scores between PD stages 3 to 6 indicates that the risk of developing dementia increases with disease progression. In some individuals, however, cognitive decline can develop in the presence of mild Parkinson disease-related cortical pathology and, conversely, widespread cortical lesions do not necessarily lead to cognitive decline.
Key findings
- Results It was possible to assign all patients to one of the PD stages.
- MMSE scores correlated with neuropathologic stages (p Conclusions The decrease in median Mini-Mental State Examination scores between PD stages 3 to 6 indicates that the risk of developing dementia increases with disease progression.
Why it matters
In 88 people with Parkinson disease from one clinic, examined after brain tissue staging, lower memory-and-thinking (MMSE) scores went with more advanced Parkinson-related brain changes, and median scores fell between stages 3 and 6. The authors caution that this is not true for every person: some declined with only mild changes, while others had widespread changes without decline. The study concerns Parkinson disease, not the treatment, cure or prevention of Alzheimer's disease.
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Study details
- Participants88
- Evidence strengthModerate
How this study scored 57/100
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 | 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 | 2005 — older than 20 years, still counted |
| Sample size | 1 / 4 | 88 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 561 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 24.4 citations a year over 23 year(s) since 2005 |
| Impact for its field and year | 5 / 6 | Cited 22.4× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 23 other studies in this library |
| Still being cited | 2 / 4 | Cited 35 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Rob A. I. de Vos: h-index 51 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Goethe University Frankfurt: institution h-index 958 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 15851731) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 57 / 100 | — |
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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
Braak, H., Rüb, U., Jansen Steur, E. N., Del Tredici, K., & de Vos, R. A. (2005). Cognitive status correlates with neuropathologic stage in Parkinson disease. Neurology. https://doi.org/10.1212/01.wnl.0000158422.41380.82
Vancouver
Braak H, Rüb U, Jansen Steur EN, Del Tredici K, de Vos RA. Cognitive status correlates with neuropathologic stage in Parkinson disease. Neurology. 2005. doi:10.1212/01.wnl.0000158422.41380.82. PMID: 15851731.
BibTeX
@article{braak2005-15851731,
author = {Braak, H. and Rüb, U. and Jansen Steur, E. N. and Del Tredici, K. and de Vos, R. A.},
title = {{Cognitive status correlates with neuropathologic stage in Parkinson disease}},
journal = {Neurology},
year = {2005},
doi = {10.1212/01.wnl.0000158422.41380.82},
pmid = {15851731},
url = {https://doi.org/10.1212/01.wnl.0000158422.41380.82}
}
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