Change search
ReferencesLink to record
Permanent link

Direct link
Cognitive function in early Parkinson's disease: a population-based study
Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience.
Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience.
Show others and affiliations
2009 (English)In: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 16, no 12, 1278-1284 p.Article in journal (Refereed) Published
Abstract [en]

BACKGROUND AND PURPOSE: The study aims to describe the frequency, pattern and determinants of cognitive function in patients with newly diagnosed Parkinson's disease (PD); to compare patients with impaired cognition to patients with intact cognition; and to compare to matched healthy controls.

METHODS: Patients were identified in a longitudinal population based study of idiopathic non-drug induced parkinsonism. Eighty-eight newly diagnosed patients with PD and no dementia were included during a four year period. The patients and 30 age- and sex-matched healthy control subjects underwent a comprehensive neuropsychological assessment.

RESULTS: Patients performed significantly worse than healthy controls in a majority of neuropsychological tests. Test results in attention, psychomotor function, episodic memory (free recall), executive function and category fluency were significantly lower in the patient group. Comparison with normative data revealed that 30% of the patients had deficits in > or =1 cognitive domain (episodic memory, executive function and verbal function). Seventy per cent of the patients had normal performance. Unified Parkinson's Disease Rating Scale (UPDRS) III sub scores; speech, facial expression, rigidity and bradykinesia were significantly higher, and disease duration shorter amongst the cognitively impaired than amongst the cognitively intact patients. Tremor showed no difference. Education level was an independent predictor of dysfunction in patients with > or =2 cognitive domains affected.

CONCLUSION: Cognitive dysfunction is common in untreated patients in early PD, affecting attention, psychomotor function, episodic memory, executive function and category fluency. Education level was an independent predictor of severe cognitive dysfunction.

Place, publisher, year, edition, pages
John Wiley & Sons, 2009. Vol. 16, no 12, 1278-1284 p.
National Category
Geriatrics Neurology
URN: urn:nbn:se:umu:diva-30600DOI: 10.1111/j.1468-1331.2009.02707.xPubMedID: 19538208OAI: diva2:284857
Available from: 2010-01-08 Created: 2010-01-08 Last updated: 2013-11-27Bibliographically approved
In thesis
1. Cognitive and motor dysfunction in the early phase of Parkinson's disease
Open this publication in new window or tab >>Cognitive and motor dysfunction in the early phase of Parkinson's disease
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Alternative title[sv]
Kognitiv och motorisk funktion i tidig fas av Parkinsons sjukdom.
Abstract [en]

Background: Parkinson’s disease (PD) is a chronic and progressive neurodegenerative disease. The diagnosis is based on a combination of the motor signs: tremor, bradykinesia, rigidity and postural abnormalities. Mild Cognitive Impairment (MCI) is common early in the disease and a large proportion of patients with PD develop dementia (PDD). Associations between motor symptoms and cognitive decline have been suggested but the results are inconclusive due to differences in the selection of participants and variables tested. Large population based studies with comprehensive neuropsychological investigation in newly diagnosed cases with PD followed prospectively are rare. The aim of this thesis was to improve characterization and understanding of cognition in PD, and to explore the relationship to motor impairment in the early phase of PD.

Methods: All new patients with suspected idiopathic parkinsonism in the catchment area (142 ooo inhabitants) were examined during a period of five years and four months. Among other investigations, a comprehensive neuropsychological evaluation was carried out in 119 of 148 patients with PD together with 30 age matched healthy controls. Assessments were repeated after one three and five years.

Results: Patients performed worse than healthy controls in a majority of neuropsychological tests. MCI at the time of diagnosis were found in 36% according to recently published MCI criteria. Thirty % were cognitively impaired using another definition. One fourth of the patients developed PDD within five years after diagnosis and 25 % of those with MCI at baseline reversed back to normal cognition. Age and MCI were significant predictors of dementia. Education was an independent predictor for severe cognitive dysfunction at diagnosis but did not predict PDD. Patients with MCI converting to PDD had worse performance on visuospatial function, semantic fluency, episodic memory, mental flexibility and conceptual thinking. There were no differences in cognitive performance between patients with predominant Postural and Gait Disturbances (PIGD) and the tremor dominant subtype at the baseline investigation and belonging to the PIGD subgroup at baseline did not predict PDD. Dementia converters declined more rapidly than non-converters in posture/gait function. Associations between bradykinesia and measures of executive functions and working memory were found, and between posture and gait disturbances and visuospatial function. Some of these associations were persistent after one year. Patients receiving the dopamine agonist pramipexole performed significantly worse on a measure of verbal fluency at the one year follow up.

Conclusions: The differences in proportions of cognitively impaired in the different studies emphasize the value of joint criteria for PD-MCI. Even when using such criteria, a substantial proportion of patients revert back to normal function. The increase in motor disability in patients with PDD could have several different causes that need to be further investigated. Associated motor and cognitive dysfunctions could reflect common pathophysiological processes in partly shared networks. Both dopaminergic and non-dopaminergic motor and cognitive functions seems to be involved in PDD which suggests that pharmacological treatment in PD needs to go beyond the scope of dopaminergic deficiency in search for new therapies that would also be effective for non-motor symptoms.

Place, publisher, year, edition, pages
Umeå: Umeå Universitet, 2013. 70 p.
Umeå University medical dissertations, ISSN 0346-6612 ; 1615
Parkinson's disease, Mild Cognitive Impairment, Dementia, population based, prospective, newly diagnosed
National Category
Research subject
urn:nbn:se:umu:diva-82897 (URN)978-91-7459-767-7 (ISBN)
Public defence
2013-12-13, Hörsal E04, byggnad 6E, Norrlands universitetssjukhus, Umeå, 13:00 (Swedish)
Available from: 2013-11-22 Created: 2013-11-13 Last updated: 2013-11-22Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Elgh, EvaDomellöf, MagdalenaLinder, JanEdström, MonaStenlund, HansForsgren, Lars
By organisation
Geriatric MedicineDepartment of Pharmacology and Clinical NeuroscienceEpidemiology and Global Health
In the same journal
European Journal of Neurology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 190 hits
ReferencesLink to record
Permanent link

Direct link