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Prevalence and characteristics of dementia in Parkinson disease: an 8-year prospective study
Aarsland D, Andersen K, Larsen JP, Lolk A, Kragh-Sørensen P.. Archives of neurology, 2003-03-01
Topic: Risk, prevention and care in population studies
Background Few longitudinal studies of dementia in Parkinson disease (PD) have been reported, and the proportion of patients with PD who eventually develop dementia is unknown. Objective To examine the 8-year prevalence, characteristics, and risk factors of dementia in patients with PD. Methods Patients were recruited from an epidemiological study of PD in the county of Rogaland, Norway, using explicit criteria for PD. Subjects with cognitive impairment at disease onset were excluded. A semistructured caregiver-based interview, cognitive rating scales, and neuropsychological tests were used to diagnose dementia according to criteria from the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition at baseline and 4 and 8 years later. A population-based sample of 3295 subjects in the municipality of Odense, Denmark, was used as a comparison group and examined at baseline and after 2 and 5 years. Results We included 224 patients with PD (116 women). At baseline, 51 patients (26%) had dementia. Fifty-five patients died, and 10 refused follow-up without their dementia status known. Forty-three and 28 new cases of dementia were identified at the 4- and 8-year evaluations, respectively. The 4-year prevalence of dementia in PD was nearly 3 times higher than in the non-PD group. The 8-year prevalence in PD was 78.2% (95% confidence interval [CI], 71.1-84.0). Risk factors for dementia were hallucinations before baseline (odds ratio [OR] = 3.1; 95% CI, 1.6-6.2) and akinetic-dominant or mixed tremor/akinetic PD (OR = 3.3; 95% CI, 1.2-8.5). Conclusions More than three quarters of this representative PD cohort developed dementia during the 8-year study period. Early hallucinations and akinetic-dominant PD were associated with an increased risk of dementia.
Key findings
- Results We included 224 patients with PD (116 women).
- Early hallucinations and akinetic-dominant PD were associated with an increased risk of dementia.
Why it matters
In an 8-year study, 78.2% of Parkinson's disease patients developed dementia, and early hallucinations and a certain type of Parkinson's were linked to higher risk. This describes the risk of dementia in Parkinson's but does not test any treatment or prevention for Alzheimer's.
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Study details
- Study designlongitudinal study
- Participants224
- Effect size78.2%; OR = 3.3
- Evidence strengthModerate
How this study scored 68/100
Published in a peer-reviewed journal, and it is a longitudinal study following the same people over time. Scored zero for randomised / blinded because the record does not state it. We have no data on institution's track record, so that was left out: it earned 66 of the 97 points we could judge it on, which is 68 out of 100.
| 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 | 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 | 2003 — older than 20 years, still counted |
| Sample size | 2 / 4 | 224 participants |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| 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 | 7 / 7 | Cited 1,404 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 56.2 citations a year over 25 year(s) since 2003 |
| Impact for its field and year | 5 / 6 | Cited 33.4× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 64 other studies in this library |
| Still being cited | 3 / 4 | Cited 128 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 1 / 4 | Last-listed author Anette Lolk: h-index 10 (OpenAlex, whole career) |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 0 institution(s) in 0 countries — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 12633150) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 66 / 97 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 66 of the 97 points we could judge it on is 68 out of 100. |
| Total | 68 / 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
Aarsland, D., Andersen, K., Larsen, J. P., Lolk, A., & Kragh-Sørensen, P. (2003). Prevalence and characteristics of dementia in Parkinson disease: an 8-year prospective study. Archives of neurology. https://doi.org/10.1001/archneur.60.3.387
Vancouver
Aarsland D, Andersen K, Larsen JP, Lolk A, Kragh-Sørensen P. Prevalence and characteristics of dementia in Parkinson disease: an 8-year prospective study. Archives of neurology. 2003. doi:10.1001/archneur.60.3.387. PMID: 12633150.
BibTeX
@article{aarsland2003-12633150,
author = {Aarsland, D. and Andersen, K. and Larsen, J. P. and Lolk, A. and Kragh-Sørensen, P.},
title = {{Prevalence and characteristics of dementia in Parkinson disease: an 8-year prospective study}},
journal = {Archives of neurology},
year = {2003},
doi = {10.1001/archneur.60.3.387},
pmid = {12633150},
url = {https://doi.org/10.1001/archneur.60.3.387}
}
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