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Longitudinal study of normal cognition in Parkinson disease
Open accessAbstract
OBJECTIVE: To report the rates and predictors of progression from normal cognition to either mild cognitive impairment (MCI) or dementia using standardized neuropsychological methods. METHODS: A prospective cohort of patients diagnosed with Parkinson disease (PD) and baseline normal cognition was assessed for cognitive decline, performance, and function for a minimum of 2 years, and up to 6. A panel of movement disorders experts classified patients as having normal cognition, MCI, or dementia, with 55/68 (80.9%) of eligible patients seen at year 6. Kaplan-Meier curves and Cox proportional hazard models were used to examine cognitive decline and its predictors. RESULTS: We enrolled 141 patients, who averaged 68.8 years of age, 63% men, who had PD on average for 5 years. The cumulative incidence of cognitive impairment was 8.5% at year 1, increasing to 47.4% by year 6. All incident MCI cases had progressed to dementia by year 5. In a multivariate analysis, predictors of future decline were male sex (p = 0.02), higher Unified Parkinson's Disease Rating Scale motor score (p ≤ 0.001), and worse global cognitive score (p < 0.001). CONCLUSIONS: Approximately half of patients with PD with normal cognition at baseline develop cognitive impairment within 6 years and all new MCI cases progress to dementia within 5 years. Our results show that the transition from normal cognition to cognitive impairment, including dementia, occurs frequently and quickly. Certain clinical and cognitive variables may be useful in predicting progression to cognitive impairment in PD.
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“A 6-year longitudinal study of 141 PD patient with average disease duration of 5 years and a mean age of 69 years showed a cumulative risk of dementia increasing from 8.5% at 1 year to nearly 50% by year 6 (Pigott et al. 2015).”
From The clinical symptoms of Parkinson's disease. (2016) · cites this paper as Pigott et al. 2015
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Metadata
- Authors
- Pigott, K., Rick, J., Xie, S. X., Hurtig, H., Chen-Plotkin, A., Duda, J. E., Morley, J. F., Chahine, L. M., Dahodwala, N., Akhtar, R. S., Siderowf, A., Trojanowski, J. Q., & Weintraub, D.
- Affiliations
- Veterans Health Administration (US)
- From the Departments of Neurology (K.P., J.R., H.H., A.C.-P., J.E.D., J.F.M., L.M.C., N.D., R.S.A., D.W.), Pathology and Laboratory Medicine (J.Q.T.), and Psychiatry (D.W.), Perelman School of Medicine at the University of Pennsylvania; the Department of Biostatistics and Epidemiology (S.X.X.), University of Pennsylvania; Philadelphia Veterans Affairs Medical Center (J.E.D., J.F.M., D.W.); and Avid Radiopharmaceuticals (A.S.), Philadelphia, PA.
- ORCID
- Venue
- Neurology
- Published
- 2015-10-13
- Volume
- 85
- Issue
- 15
- Pages
- 1276-1282
- ISSN
- 0028-3878 (ISSN-L)
- 1526-632X
- PMC
- PMC4617168
- OpenAlex
- W1414124913
- Cited by
- 251
- References
- 34
- Citations by year
- 2026: 9 · 2025: 22 · 2024: 26 · 2023: 23 · 2022: 28 · 2021: 27 · 2020: 24 · 2019: 19 · 2018: 24 · 2017: 30 · 2016: 18 · 2015: 1
- FWCI
- 19.77
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Neurology (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- U.S. Department of Veterans Affairs
- Michael J. Fox Foundation for Parkinson's Research
- Bristol-Myers Squibb
- Eli Lilly and Company
- Pfizer
- American Brain Foundation
- CHDI Foundation
- Teva Pharmaceutical Industries
- University of Pennsylvania
- ACADIA Pharmaceuticals
- Avanir Pharmaceuticals
- H. Lundbeck A/S
- National Institutes of Health (AG 17586, NS053488)
- Avid Radiopharmaceuticals
- National Institute on Aging (AG 024904, AG 029213, AG-19724, P30AG010124, P01AG017586, AG17586, AG-10124, U01AG029213, K23AG034236, P01AG032953, P01AG019724)
- National Institute of Neurological Disorders and Stroke (NS053488, P50NS053488, K08NS093127, U01NS082134, UO1 NS082134)
- Topics
- Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
- Health Sciences › Medicine › Clinical Neurology › Parkinson's Disease Mechanisms and Treatments
- Life Sciences › Neuroscience › Neurology › Neurological diseases and metabolism
- Keywords
- Parkinson's disease, cognitive impairment, mild cognitive impairment, dementia, cognitive decline, conversion to dementia, predictors of cognitive decline, sex differences, motor score, Unified Parkinson's Disease Rating Scale
- MeSH terms
- Aged, Cognition, Female, Humans, Longitudinal Studies, Male, Middle Aged, Neuropsychological Tests, Parkinson Disease, Prospective Studies, Disease Progression, Cognitive Dysfunction
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