Amyloid Beta and Cognition in Parkinson Disease

Participants with PD will be studied at initial visit assessing clinical, cognitive, and brain imaging. A one year and, if applicable, three year cognitive assessment will be done, and the entire/complete assessment (same as initial visit) will be repeated again at two years. There will be a maximum of three follow up visits. The imaging test battery will consist of amyloid and acetylcholine brain PET and MRI scans. The use of acetylcholine PET imaging will demonstrate how changes in activity of this neurotransmitter relate to changes in cognitive functions, such as memory and mental concentration. A key question will be whether persons with PD who not only are losing acetylcholine brain cells but also have the buildup of the Alzheimer amyloid protein have a more rapid progression with more severe cognitive decline and behavioral changes compared to persons who do not have the amyloid protein.

Inclusion criteria

PD diagnosis according to the UK PD Society of Brain Bank research Center criteria PD subjects at risk for dementia Age 50 and above, male or female Absence of dementia confirmed by clinical and detailed neurological assessment -

Exclusion criteria

Subjects with contra-indications to MR imaging Evidence of large vessel stroke or mass on on MRI Use of cholinergic or neuroleptic drugs at baseline Evidence of atypical parkinsonism on neurological exam Subjects limited by participation in research procedures involving ionizing radiation Pregnancy(test within 48 hours of each PET session) or breastfeeding

-