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Parkinson disease-associated cognitive impairment
Aarsland D, Batzu L, Halliday GM, Geurtsen GJ, Ballard C, Ray Chaudhuri K, Weintraub D.. Nature reviews. Disease primers, 2021-07-01
Topic: Risk, prevention and care in population studies
Parkinson disease (PD) is the second most common neurodegenerative disorder, affecting >1% of the population ≥65 years of age and with a prevalence set to double by 2030. In addition to the defining motor symptoms of PD, multiple non-motor symptoms occur; among them, cognitive impairment is common and can potentially occur at any disease stage. Cognitive decline is usually slow and insidious, but rapid in some cases. Recently, the focus has been on the early cognitive changes, where executive and visuospatial impairments are typical and can be accompanied by memory impairment, increasing the risk for early progression to dementia. Other risk factors for early progression to dementia include visual hallucinations, older age and biomarker changes such as cortical atrophy, as well as Alzheimer-type changes on functional imaging and in cerebrospinal fluid, and slowing and frequency variation on EEG. However, the mechanisms underlying cognitive decline in PD remain largely unclear. Cortical involvement of Lewy body and Alzheimer-type pathologies are key features, but multiple mechanisms are likely involved. Cholinesterase inhibition is the only high-level evidence-based treatment available, but other pharmacological and non-pharmacological strategies are being tested. Challenges include the identification of disease-modifying therapies as well as finding biomarkers to better predict cognitive decline and identify patients at high risk for early and rapid cognitive impairment.
Key findings
- Other risk factors for early progression to dementia include visual hallucinations, older age and biomarker changes such as cortical atrophy, as well as Alzheimer-type changes on functional imaging and in cerebrospinal fluid, and slowing and frequency variation on EEG.
- However, the mechanisms underlying cognitive decline in PD remain largely unclear.
- Cortical involvement of Lewy body and Alzheimer-type pathologies are key features, but multiple mechanisms are likely involved.
- Cholinesterase inhibition is the only high-level evidence-based treatment available, but other pharmacological and non-pharmacological strategies are being tested.
- Challenges include the identification of disease-modifying therapies as well as finding biomarkers to better predict cognitive decline and identify patients at high risk for early and rapid cognitive impairment.
Why it matters
This review describes cognitive impairment in Parkinson disease, including risk factors for progression to dementia and the fact that cholinesterase inhibition is the only treatment with high-level evidence. It notes that the mechanisms underlying cognitive decline in Parkinson disease remain largely unclear and that disease-modifying therapies are still being sought.
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Study details
- Evidence strengthLow
How this study scored 59/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Nature reviews. Disease primers) |
| Journal's citation record | 3 / 4 | Nature Reviews Disease Primers: journal h-index 281 (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 | 3 / 5 | 2021 — within 6 year(s) of the newest study here |
| 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 | 7 / 7 | Cited 1,379 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 197.0 citations a year over 7 year(s) since 2021 |
| Impact for its field and year | 5 / 6 | Cited 27.3× 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 | 4 / 4 | Cited 1,001 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Daniel A. Weintraub: h-index 115 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Pennsylvania: institution h-index 1,859 (OpenAlex) |
| Multi-centre collaboration | 3 / 3 | OpenAlex lists 10 institution(s) in 5 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 34210995) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 59 / 100 | — |
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Read the original
- DOI: 10.1038/s41572-021-00280-3
- PubMed: 34210995
- Original source →
- Free full text: Nature Reviews Disease Primers →
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. The record names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Aarsland, D., Batzu, L., Halliday, G. M., Geurtsen, G. J., Ballard, C., Ray Chaudhuri, K., et al. (2021). Parkinson disease-associated cognitive impairment. Nature reviews. Disease primers. https://doi.org/10.1038/s41572-021-00280-3
Vancouver
Aarsland D, Batzu L, Halliday GM, Geurtsen GJ, Ballard C, Ray Chaudhuri K, et al. Parkinson disease-associated cognitive impairment. Nature reviews. Disease primers. 2021. doi:10.1038/s41572-021-00280-3. PMID: 34210995.
BibTeX
@article{aarsland2021-34210995,
author = {Aarsland, D. and Batzu, L. and Halliday, G. M. and Geurtsen, G. J. and Ballard, C. and Ray Chaudhuri, K. and Weintraub, D.},
title = {{Parkinson disease-associated cognitive impairment}},
journal = {Nature reviews. Disease primers},
year = {2021},
doi = {10.1038/s41572-021-00280-3},
pmid = {34210995},
url = {https://doi.org/10.1038/s41572-021-00280-3}
}
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