Dementia in Parkinson's disease.

Advanced Parkinson's disease (PD) is frequently associated with dementia. The pathogenesis of this dementia is complex, related to deficiency of several biogenic amines and cortical Lewy body deposition, as well as co-existent age-related brain changes, both of the Alzheimer's type and vascular. However, degeneration of the cholinergic neurons in the nucleus basalis of Meynert may have an important contribution to the cognitive decline. The dementia of PD has a grave effect on the quality of life of the patients and their caregivers, as well as negative effect on their survival. The treatment of dementia associated with PD therefore must encompass several agents. We have treated several patients with the cholinesterase inhibitor rivastigmine which produced gratifying results. Future studies should define the exact role of this agent in the treatment of the dementia of PD.