# Parkinson's and PPMI Research Notes
By Arya Anantula
## Parkinson's Disease
Parkinson's disease (PD) is a neurodegenerative disease (nerve cells in the brain or peripheral nervous system lose function over time and ultimately die) that affects around a million people in the US. It occurs when brain cells responsible for the creation of dopamine, a chemical that coordinates movement, stop working or die.
**Some symptoms include:**
- Tremors (shaking or trembling in one or more parts of the body)
- Slowness
- Stiffness
- Walking and balance problems
- Constipation
- Depression
- Memory problems
- Loss of smell
- Trouble sleeping
- Soft or low voice
PD is a lifelong and progressive disease, which means that the symptoms worsen over time. However, the experience of living with PD is unique to each person because symptoms vary from person to person. Though there are general paths of similarity among people with PD, there isn't any certainty that you will experience the same symptoms as others.
The cause of PD remains largely unknown. Scientists believe that a combination of genetic and environmental factors are the cause.
**Stages of early PD:**
- Preclinical: The degeneration of the dopamine producing neurons has already begun, but no clinical symptom is evident yet.
- Prodromal: Some symptoms are present, but they are insufficient for the clinician to make a diagnosis of PD.
- Clinical: Parkinsonian symptoms have manifested and are clearly recognizable.
Parkinsonism is a term used to describe the collection if signs and movement symptoms associated with several conditions, including PD. Symptoms mimic those of PD (tremors, slowness, stiffness, etc.) but the underlying causes can be different.
Because of the diverse nature of the disease and the similarity it has to other Parkinsonism diseases, PD can be difficult to classify in a person. It is challenging to find the correct biomarkers and attributes to look at to determine PD.
## PPMI
Parkinson's Progression Markers Initiative (PPMI) is a study aimed at creating an open-access dataset to expedite scientific breakthroughs and treatments. PPMI has an emphasis on signals in at-risk individuals to identify the disease and intervention points as early as possible. It aims to identify biomarkers of Parkinson's risk, onset, and progression. It provides the research community with a comprehensive, standardized, longitudinal dataset.
It accesses the progression of clinical features, imaging outcomes, biologic and genetic markers, and digital outcomes of Parkinson’s disease across all stages of PD.
**Study Design**
1. PPMI Online: Patient-reported outcomes collected online from people with and without PD.
- N = ~100,000
2. PPMI Remote: Remotely administered olfactory and, in some, genetic testing among people selected based on patient reported outcomes (PROs) or information from clinical sites.
- N = ~50,000
3. PPMI Clinical: In-person longitudinal clinical and imaging assessments and biosample collection taking place at ~50 international sites. PPMI clinical prodromal participants will largely be identified through a stage risk paradigm beginning with a custom-built remote platform - PPMI online. All PPMI clinical participants will also participate in PPMI online longitudinally.
- N = ~4,000
**PPMI Clinical Data Collection**
Clinical Data Collection:
- Motor Assessments
- Neurobehavioral/Neuropsychiatric Testing
- Autonomic, Olfaction, Sleep Testing
- DaTSCAN, MRI, and other imaging sub-studies
- Digital Data
- Online patient reported outcomes (PROs)
Biologic Collection:
- DNA, RNA
- Whole Blood, Serum, Plasma, Urine
- CSF
- iPSC in Subset of 2010 - 2018
- Skin biopsy
- Post-mortem tissue
## Parkinson's References
[1] https://www.michaeljfox.org/parkinsons-101
[2] https://www.parkinson.org/understanding-parkinsons
[3] https://www.niehs.nih.gov/research/supported/health/neurodegenerative/
## PPMI References
[1] https://www.ppmi-info.org/
[2] [PPMI Data User Guide](https://ida.loni.usc.edu/download/files/study/cd4c3ab1-9801-4c97-9044-0c0a084bc09e/file/ppmi/PPMI_Data_User_Guide_v.1.1.pdf)