North American Prodromal Synucleinopathy Consortium Stage 2

Prior treatment

• Diagnosis of PD, dementia of any type, or MSA unless previous participant in NAPS1.

Other illness

• In the opinion of the investigator, the individual has a clinically significant uncontrolled medical condition that would impede safe completion of the study protocol
• History of dream enactment behavior to suggest RBD
• Parkinsonism, MSA, dementia, or mild cognitive impairment
• Active central nervous system, systemic, psychiatric condition or use of psychoactive medication that would adversely affect cognitive, neuropsychiatric, motor, or autonomic functioning.
• In the opinion of the investigator, the individual has a clinically significant uncontrolled medical condition that would impede safe completion of the study protocol

Other

• Narcolepsy-associated RBD
• RBD secondary to any known cause except prodromal synucleinopathy.
• Participation in a clinical trial, except by specific permission by the Executive Committee
• Contraindications to complete MRI.
• Contraindications to lumbar puncture.
• Participation in a clinical trial, except by specific permission by the Executive Committee

• Polysomnogram-confirmed RBD by ICSD-3 criteria
• Capable of providing informed consent at time of study enrollment
• Age \> 18 years
• Ability to provide written consent
• Age \> 18 years
• Must meet age, sex, and race matching criteria per the Data Management and Statistical core recommendations for the site
• Must be willing to undergo all testing procedures, including neuroimaging and lumbar puncture.
• Normal capacity to perform complex activities of daily living independently based on informant or physician report