Current Neurology and Neuroscience Reports

, Volume 11, Issue 4, pp 371–378 | Cite as

Mild Cognitive Impairment in Parkinson’s Disease

  • Dag AarslandEmail author
  • Kolbjørn Brønnick
  • Tormod Fladby


Prospective studies conducted during the last decade have shown that the majority of patients with Parkinson’s disease (PD) develop dementia. In addition, using a variety of definitions and methods, more recent research suggests that approximately a quarter of PD patients without dementia have mild cognitive impairment (PD-MCI). Furthermore, several studies have shown that approximately 20% have MCI even at time of diagnosis of PD. The typical cognitive deficits include visuospatial, attentional, and executive deficits, but memory deficits have also been shown. The etiology of PD-MCI is not known, but it is likely that mechanisms known to contribute to dementia in PD (ie, limbic and cortical Lewy bodies, amyloid plaques, and cholinergic deficits) play a role, in addition to dysfunction of dopaminergic frontostriatal circuits. PD-MCI predicts a shorter time to dementia, and preliminary evidence suggests that this is particularly true for posterior cognitive deficits. There are currently no systematic clinical trials in PD-MCI.


Parkinson’s disease Cognitive impairment Dementia Visuospatial functions Executive functions Memory Attention Imaging Biomarker Cerebrospinal fluid Pathology Dopamine Acetylcholine Noradrenaline 



Conflicts of interest: D. Aarsland: has board membership for DiaGenic, and has been a consultant for Novartis, Lundbeck, GE Health, and Merck Serono; K. Brønnick: none; T. Fladby: none.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Dag Aarsland
    • 1
    • 5
    Email author
  • Kolbjørn Brønnick
    • 2
  • Tormod Fladby
    • 3
    • 4
  1. 1.Centre for Age-Related Diseases, Division of PsychiatryStavanger University HospitalStavangerNorway
  2. 2.Norwegian Centre for Movement DisordersStavanger University HospitalStavangerNorway
  3. 3.Department of NeurologyAkershus University HospitalLørenskogNorway
  4. 4.Faculty Division Akershus University HospitalUniversity of OsloOsloNorway
  5. 5.Karolinska Institutet, Department NVS, KI Alzheimer Disease Research CenterStockholmSweden

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