This study is designed as a prospective cohort study to test the strategy of combining two biomarkers of parkinsonism, olfaction and brain imaging with a radioactively labeled drug, [123I]β-CIT , in a population of first-degree relatives of PD patients as a tool to establish an 'at risk' Parkinson disease cohort without motor symptoms of PD. First-degree relatives of PD will be recruited through PD research sites and national foundations to participate in this study. In addition, first degree relatives of PD patients will be recruited directly through advertising.
Primary Outcome Measures:
- the mean striatal uptake of [123I]B-CIT in first-degree relatives with a loss of odor identification, compared to an established healthy control database (age 40-70; n=50) [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
Secondary Outcome Measures:
- Estimate the frequency of olfactory loss of first-degree relatives of PD patients [ Time Frame: 1 year ] [ Designated as safety issue: No ]
- Compare striatal DAT imaging in first-degree relatives of PD patients without signs or symptoms of PD with olfactory loss to age matched healthy controls [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]
- Determine if a reduction in DAT density using [123I]B-CIT and SPECT imaging in first-degree relatives of PD patients without signs or symptoms of PD at baseline predicts the onset of clinical PD at 2-year follow-up [ Time Frame: 1 year ] [ Designated as safety issue: No ]
| Estimated Enrollment: |
3000 |
| Study Start Date: |
November 2006 |
| Estimated Primary Completion Date: |
November 2008 (Final data collection date for primary outcome measure) |
Intervention Details:
Procedure: [123I]B-CIT injection and SPECT imaging
This study is designed as a prospective cohort study to test the strategy of combining two biomarkers of parkinsonism, olfaction and brain imaging with a radioactively labeled drug, [123I]β-CIT , in a population of first-degree relatives of PD patients as a tool to establish an 'at risk' Parkinson disease cohort without motor symptoms of PD.
First-degree relatives that agree to participate (n=3,000) will be asked to complete a 40-item olfactory identification test provided by mail. 300 subjects (225 with decreased odor identification and 75 with normal olfaction) will be invited to undergo DAT imaging at the Institute for Neurodegenerative Disorders in New Haven, CT. There will also be additional clinical follow-up at participant's clinical (local) site. The primary outcome measure for the study will be the mean striatal uptake of [123I]B-CIT in first-degree relatives with a loss of odor identification, which will be compared to an established healthy control database (age 40-70; n=50). 300 relatives will be followed longitudinally with clinical evaluations and a second imaging study completed after two years. Comparing the first and second scans in this subset of subjects will allow us to evaluate the rate of progressive loss in dopamine transporter density during this pre-symptomatic period.
Purpose
