Cognitive Impairment in Parkinson’s Disease: What We Know so Far

Figures & data

Box 1 Key Points

Cognitive deficits are common in PD even in early stages and over 75% of PD patients will present dementia over time.^Citation4–Citation6

The combination of Lewy pathology and Alzheimer’s disease (AD) pathologies (ie beta-amyloid plaques and neurofibrillary tangles) is the most robust pathological correlate of PDD.

Pathological and neuroimaging studies consistently support an association for a cholinergic deficit with cognition in PD^Citation33–Citation38

Specific diagnostic clinical criteria have been established for PD-MCI and PDD.^Citation9,Citation10

The difference between MCI and PDD is based on the extent to which cognitive impairment interferes with daily life activities.^Citation9,Citation10

PD-MCI entails an increased risk of dementia. However, some patients with PD-MCI will revert to normal cognition.

Older age, postural instability-gait disorder phenotype, psychiatric symptoms as psychosis, hallucinations, and depression, REM sleep behavior disorder, and diurnal sleepiness have been associated with PD cognitive worsening.^Citation10,Citation18–Citation21

Low levels of Aβ and increased levels of tau in the CSF at baseline might predict future cognitive decline in patients with PD.^Citation56–Citation59

Rivastigmine has been designated as clinically useful in PDD.^Citation112

There is insufficient evidence for the use of other anticholinesterase inhibitors in PD-MCI.

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