A person with PD has two to six times the risk of dementia compared to the general population.[1][2] Up to 78% of people with PD have Parkinson's disease dementia.[44] The prevalence of dementia increases with age and, to a lesser degree, duration of the disease.[45] Dementia is associated with a reduced quality of life in people with PD and their caregivers, increased mortality, and a higher probability of needing nursing home care.[42]