Mild cognitive impairment in Parkinson’s disease
Parkinson’s disease (PD) has initially been described as a clinical syndrome, although its exact definition has changed over the past centuries. The identification of the pathological changes added another level of complexity, with Lewy bodies, synuclein deposits and neuronal loss in the substantia nigra being used alternatively as criteria. A third level of complexity was added with the recognition of genetic mutations resulting in Parkinsonism, sometimes with and sometimes without Lewy bodies or synuclein deposition. Lastly, frequent additional important pre-motor manifestations, particularly depression, anosmia and sleep-associated phenomena have been described. These different points of view on the definition of PD have important implications on the study of the etiology and even the therapy of PD. Cognitive impairment is also an important feature of PD, while the spectrum of deficits ranges from none to severe dementia. The no-man land in-between normal cognition and dementia has been termed mild cognitive impairment in PD. At present, this term lacks heuristic value or clinical utility, and remains a target for scientific research.
KeywordsParkinson’s disease Dementia Mild cognitive impairment Amnesia
- Aarsland D, Bronnick K, Williams-Gray C, Weintraub D, Marder K, Kulisevsky J, Burn D, Barone P, Pagonabarraga J, Allcock L, Santangelo G, Foltynie T, Janvin C, Larsen JP, Barker RA, Emre M (2010) Mild cognitive impairment in Parkinson disease: a multicenter pooled analysis. Neurology 75:1062–1069PubMedCrossRefGoogle Scholar
- Braak H, Braak E (2000) Pathoanatomy of Parkinson’s disease. J Neurol 247:II3–II10Google Scholar
- Braak H, Del Tredici K, Bratzke H, Hamm-Clement J, Sandmann-Keil D, Rüb U (2002) Staging of the intracerebral inclusion body pathology associated with idiopathic Parkinson’s disease (preclinical and clinical stages). J Neurol 249(Suppl 3):III/1–5Google Scholar
- Korczyn AD (2002) Mixed dementia—the most common cause of dementia. Ann N Y Acad Sci 977:129–34Google Scholar
- Pillon B, Dubois B, Cusimano G, Bonnet AM, Lhermitte 298 F, Agid Y (1989) Does cognitive impairment in Parkinson’s disease result from non-dopaminergic lesions? J Neurol Neurosurg Psychiatry 52:201–206Google Scholar