Imaging Biomarkers of Progression of Mobility Impairment in Parkinson Disease

The project will apply positron emission tomography (PET) of acetylcholinesterase to study
non-dopaminergic (i.e. cholinergic) brain changes over time in subjects with Parkinson
disease. Acetylcholinesterase PET imaging was used to assess cholinergic changes over time
in this study. Acetylcholinesterase PET imaging is a diagnostic test as the investigator
does not assign specific interventions to the subjects of the study based on the
acetylcholinesterase PET. Therefore, this is an observational study as defined as following:
studies in human beings in which biomedical and/or health outcomes are assessed in
pre-defined groups of individuals. Subjects in the study may receive diagnostic,
therapeutic, or other interventions, but the investigator does not assign specific
interventions to the subjects of the study.

Inclusion Criteria:

- Patients who meet the UK Parkinson's Disease Society Brain Bank Research Center
clinical diagnostic criteria for PD.

- Hoehn and Yahr stages 1-2.5 at initial recruitment in baseline study.

- Absence of dementia confirmed by neuropsychological testing at initial recruitment in
baseline study.

Exclusion Criteria:

- contra-indication for magnetic resonance study

- Pregnancy or breastfeeding