Cognitive Impairment and Dementia in Parkinson Disease.

In the comprehensive care of people with Parkinson disease (PD), recognition of cognitive impairment is essential. Cognitive impairment in PD can be varied in its clinical features and rates of progression and is now recognized to occur throughout the disease, from early, de novo to more advanced stages. However, the many factors related to the disease itself, underlying pathologies, comorbidities, and genetics may play a role in the development of mild cognitive impairment (PD-MCI) and dementia (PDD). To date, the field lacks curative or disease-modifying treatments for PD cognitive impairment and has few effective, robust symptomatic therapies for PDD or PD-MCI.