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