Mild Cognitive Impairment and Dementia in Patients with Parkinson's Disease

Cognitive deficits are frequent symptoms in patients with Parkinson's disease (PD) and typically include executive dysfunctions, memory dysfunctions (especially regarding strategic encoding and retrieval) as well as deficits in visuo-spatial functions and attention. The estimated point prevalence of mild cognitive impairment in PD patients (PD-MCI) for which research criteria were published in 2012 is 27 %, and further 30 % of the patients are estimated to suffer from Parkinson's Disease Dementia (PDD); longitudinally, most patients develop cognitive dysfunctions during the course of the disease. Given that these symptoms are highly frequent and of utmost relevance, neuropsychological diagnostics should be performed in all PD patients. The acetylcholinesterase inhibitor rivastigmine is approved for the treatment of PDD; other approved treatment options for cognitive dysfunctions in PD patients do not exist yet. Evidence of efficacy of non-pharmacological interventions is insufficient. However, first studies with cognitive training and exercise are promising.