Study Cohorts

Participants with diagnosed Parkinson’s disease

All participants of the PD cohort have a clinical diagnosis of PD. The PD cohort is comprised of several subgroups, which include the following key inclusion criteria:

1. People with untreated PD¹:

   The initial phase of PPMI enrolled 423 untreated PD participants. Many of these participants continue in PPMI, and the study has enrolled an additional 600 sporadic untreated PD study participants.

2. People with PD and pathogenic genetic variant(s):

   The initial phase of PPMI enrolled 294 genetic PD participants with SNCA, LRRK2 and/or GBA variants. Many of these participants continue in PPMI, and the current recruitment expansion aims to enroll additional PD participants with pathogenic genetic variants including rare genetic variants such as Parkin, PINK1.

   For participants with LRRK2, GBA variants

   	Initial Stage	Expansion Stage
   Minimum age	18	30
   Years since diagnosis	Within 7 years	Any number of years4
   Hoehn and Yahr at Baseline	I, II, or III	Any stage4
   Medications for PD Initiated?	Allowed	Allowed

   For participants with rare genetic variants

   	Initial Stage	Expansion Stage
   Minimum age	18	30
   Years since diagnosis	Within 7 years	No Limit
   Hoehn and Yahr at Baseline	I, II, or III	I, II, or III
   Medications for PD Initiated?	Allowed	Allowed

Please see the Protocol and Protocol Clarification Letters posted on the Research Documents & SOPs page for full inclusion and exclusion criteria.

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Footnotes:

1. Because some PD participants were enrolled as early as 2010, most from the initial recruitment phase are now receiving treatment and have established motor fluctuations and/or dyskinesia.
2. A small number of individuals in the PD cohort were initially recruited into the SWEDD cohort of PPMI (see Legacy Cohorts), but later on developed PD and are now enrolled in the PD cohort of the study.
3. In a few instances, exceptions were made allowing recruitment of individuals with longer disease duration
4. Please see current and former Protocols and Protocol Clarification Letters posted on the Research Documents & SOPs page as these criteria have changed over time.