ArticleNeurology2015
Longitudinal study of normal cognition in Parkinson disease.
Article in Neurology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 140 papers, 6 of them syntheses that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
140 citing papers in PubMed, 6 syntheses or guidelines pooled it.
- Cognitive function in different motor subtypes of Parkinson's disease: A systematic review and multilevel meta-analysis.Cognitive, affective & behavioral neuroscience · 2026Pooled it
- Risk factors for mild cognitive impairment in Parkinson disease: a systematic review and meta-analysis.Molecular and cellular biochemistry · 2026Pooled it
- Effects of transcranial direct current stimulation on non-motor functions in individuals with Parkinson's disease: a systematic review and meta-analysis.Frontiers in neuroscience · 2025Pooled it
- Sex differences in alpha-synucleinopathies: a systematic review.Frontiers in neurology · 2023Pooled it
- Imaging Cognitive Impairment and Impulse Control Disorders in Parkinson's Disease.Frontiers in neurology · 2021Pooled it
- Detecting Mild Cognitive Deficits in Parkinson's Disease: Comparison of Neuropsychological Tests.Movement disorders : official journal of the Movement Disorder Society · 2018Pooled it
- Complex Exercises Improve Cognition in People With Parkinson's Disease and Freezing of Gait.Neurorehabilitation and neural repair · 2025Trial
- Pimavanserin for Parkinson's Disease psychosis: Effects stratified by baseline cognition and use of cognitive-enhancing medications.Movement disorders : official journal of the Movement Disorder Society · 2018Trial
- Dementia Incidence in Individuals With Parkinson's Disease in the Framingham Heart Study.Annals of clinical and translational neurology · 2026Article
- Early Autonomic Burden in Prodromal Parkinson's Disease Predicts Cognitive Impairment.Movement disorders : official journal of the Movement Disorder Society · 2026Article
- Motor-Derived Digital Biomarkers for Identifying Low-MoCA Status in People with Parkinson's Disease.Sensors (Basel, Switzerland) · 2026Article
- Misfolded Proteins and Cognitive Decline: Mechanistic Insights into Neurodegenerative Disorders.Neurology international · 2026Review
- Association of Statin use with Parkinson's Disease Progression in a Prospective Cohort Study and Multi-omics Analyses.Journal of molecular neuroscience : MN · 2026Article
- Visuospatial dysfunction indicates an increased risk of rapid dementia conversion in Parkinson's disease.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2026Article
- Utilization of Neurology and Allied Health Services by People With Parkinson's Disease in Israel: A Retrospective Observational Study.Journal of neurologic physical therapy : JNPT · 2025Observational
- Effectiveness of Electroencephalographic Neurofeedback for Parkinson's Disease: A Systematic Review and Meta-Analysis.Journal of clinical medicine · 2025Review
- Improving Prediction of Falls and Cognitive Impairment in Parkinson Disease: Protocol for a Decentralized Observational Study.JMIR research protocols · 2025Article
- Cortical α-synuclein pathology induces cell autonomous neuronal hypoactivity and compensatory circuit changes in a model of early Lewy body dementia.bioRxiv : the preprint server for biology · 2025Article
- Mild cognitive impairment is not predictive of dementia up to 15 years after subthalamic deep brain stimulation in Parkinson's disease.Journal of Parkinson's disease · 2025Article
- Calcium modulating ligand confers risk for Parkinson's disease and impacts lysosomes.Annals of clinical and translational neurology · 2025Article
80 more citing papers are in PubMed but not listed here.
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Authors and funding
13 authors.
Funding
Abstract
objectiveTo report the rates and predictors of progression from normal cognition to either mild cognitive impairment (MCI) or dementia using standardized neuropsychological methods.
methodsA 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.
resultsWe 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).
conclusionsApproximately 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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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.