The DOI matches its Crossref record; 25 of the 25 references it cites were found in a registry or an index.
Cognitive impairment in incident, untreated Parkinson disease: The Norwegian ParkWest Study
Abstract
BACKGROUND: Little is known regarding the cognitive impairment in subjects with early, drug-naïve Parkinson disease (PD). The aim of this study was to explore the proportion with mild cognitive impairment (MCI) and subtypes in an incidence cohort of untreated PD in Southern and Western Norway. METHODS: A total of 196 non-demented, drug-naive patients who were recruited after an extensive search of all new cases of PD in the area and 201 healthy control subjects completed a battery of neuropsychological tests of verbal memory, visuospatial, and attentional-executive functioning. Subjects were classified as MCI if the age- and education-corrected z-score was falling 1.5 standard deviations below the mean for at least one of the cognitive domains. RESULTS: The PD group was more impaired on all neuropsychological tests than controls, but the effect sizes were small. The largest effect size was found for verbal memory. A total of 18.9% of the patients with PD were classified as MCI, with a relative risk of 2.1 (1.2-3.6) in PD compared to the control group. Patients with PD with and without MCI did not differ significantly regarding demographic and motor features. Among PD-MCI patients, nearly two-thirds had a non-amnestic MCI subtype, and one third had an amnestic MCI subtype. CONCLUSIONS: The findings demonstrate a twofold increase in the proportion with cognitive impairment in subjects with early, untreated Parkinson disease (PD) compared to controls. This has implications for diagnosis and management of PD. AD = Alzheimer disease; aMCI-MD = amnestic multiple-domain MCI; aMCI-SD = amnestic single-domain MCI; CVLT-2 = California Verbal Learning Test II; IQCode = Informant Questionnaire on Cognitive decline in the elderly; MADRS = Montgomery and Aasberg Depression Rating Scale; MCI = mild cognitive impairment; MMSE = Mini-Mental State Examination; naMCI-MD = non-amnestic multiple-domain MCI; naMCI-SD = non-amnestic single-domain MCI; PD = Parkinson disease; RR = relative risks; UPDRS = Unified Parkinson's Disease Rating Scale; VOSP = Visual Object and Space Perception Battery.
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“Mild cognitive impairment has been reported to be twice as common in PD as in people not affected by the disease (Aarsland et al. 2009).”
From The clinical symptoms of Parkinson's disease. (2016) · cites this paper as Aarsland et al. 2009
In the citing paper
“Mild cognitive impairment (MCI) is already present in about a quarter of patients with early PD.[12][13][14]”
From Does vigorous exercise have a neuroprotective effect in Parkinson disease? (2011) · cites this paper as [12]
Citations
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Apathy in Parkinson’s disease. A community-based study
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Metadata
- Authors
- Aarsland, D., Brønnick, K., Larsen, J. P., Tysnes, O. B., & Alves, G.
- Affiliations
- Stavanger University Hospital (NO)
- From The Norwegian Centre for Movement Disorders (D.A., K.B., J.P.L., G.A.), Department of Neurology (J.P.L., G.A.), and Department of Psychiatry (D.A.), Stavanger University Hospital, Stavanger; Department of Neurology (O.B.T.), Haukeland University Hospital, Bergen; and School of Medicine (D.A., J.P.L., O.B.T.), University of Bergen, Norway.
- Venue
- Neurology
- Published
- 2009-03-31
- Volume
- 72
- Issue
- 13
- Pages
- 1121-1126
- ISSN
- 0028-3878 (ISSN-L)
- 1526-632X
- OpenAlex
- W2120049868
- Cited by
- 625
- References
- 25
- Citations by year
- 2026: 13 · 2025: 19 · 2024: 24 · 2023: 19 · 2022: 33 · 2021: 34 · 2020: 33 · 2019: 39 · 2018: 34 · 2017: 44 · 2016: 43 · 2015: 40 · 2014: 40 · 2013: 53 · 2012: 48
- FWCI
- 22.96
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Neurology (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Clinical Neurology › Parkinson's Disease Mechanisms and Treatments
- Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
- Health Sciences › Medicine › Oncology › Cancer-related cognitive impairment studies
- Keywords
- Parkinson's disease, mild cognitive impairment, early-stage Parkinson's disease, amnestic MCI, non-amnestic MCI, verbal memory impairment, executive function, visuospatial ability, attention, prevalence of cognitive impairment
- MeSH terms
- Aged, Cognition Disorders, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neuropsychological Tests, Norway, Parkinson Disease, Prospective Studies, Incidence
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