Progression of Prodromal Markers of α-synucleinopathy Neurodegeneration in the FDRs of Patients With RBD

Study Overview
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Brief Summary
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This study is a prospective study with a mean of 5-year follow-up interval, aims to monitor the progression of α-synucleinopathy neurodegeneration by the evolution of prodromal markers and development of clinical disorders in first-degree relatives (FDRs) of idiopathic REM Sleep Behavior Disorder (RBD) patients and healthy controls.

Detailed Description
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Idiopathic RBD is implicated as an integral part of progression of α-synucleinopathy neurodegeneration, and patients with idiopathic RBD have increased prevalence of non-motor symptoms (or prodromal markers) closely related to Parkinson's disease(PD). Moreover, the investigator's previous studies have further confirmed the familial aggregation of RBD, and first-degree relatives (FDRs) of RBD patients had more prodromal markers of Parkinson's disease compared with FDRs of healthy controls. In these regards, current prospective study aims to map the progression and evolution of prodromal markers (including autonomic dysfunction, olfactory loss, color vision impairment, neurocognitive impairment, neuroimaging of dopamine dysfunction, daytime sleepiness and psychiatric disorders), onset of RBD, and neurodegenerative diseases. Finally, other markers, such as physical activity and circadian rhythm and tonic electromyography (EMG) activity level, which have been found to be reliably associated with Parkinson's disease or other neurodegenerative diseases. In this regard, it is also interesting to investigate whether these indicators will additionally predict the progression of prodromal markers of PD.

Official Title
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Progression of Prodromal Markers of α-synucleinopathy Neurodegeneration in the First-degree Relatives of Patients With REM Sleep Behavior Disorder: a 5-year Prospective Study

Conditions
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REM Sleep Behavior Disorder, Neurodegeneration

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Chinese aged 40 or above; Being capable of giving informed consent for participation of the study; Sex-matched. Exclusion Criteria: Younger than 40 years old (as the supposed neurodegenerative process may not have occurred); Not capable of giving informed consent for participation of the study.

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| FDRs of idiopathic RBD patients<br>First-degree relatives of idiopathic RBD patients | |
| FDRs of controls<br>First-degree relatives of controls | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of the overall probability of prodromal Parkinson's disease in the FDRs of patients with RBD. | Changes of the overall probability of prodromal Parkinson's disease will be calculated based on the Movement Disorder Society (MDS) research criteria for prodromal Parkinson's disease in the FDRs of patients with RBD. | Baseline and 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of tonic EMG activity in the FDRs of patients with RBD. | Changes of tonic EMG activity is recorded by v-PSG in the FDRs of patients with RBD. | Baseline and 5 years | 
| Changes of physical activity level and circadian in the FDRs of patients with RBD. | Changes of physical activity level and circadian are recorded by one-week actigraphy in the FDRs of patients with RBD. | Baseline and 5 years | 
| New incidence of RBD and α-synucleinopathy in the FDRs of patients with RBD. | New incidence of probable RBD, video-polysomnography (v-PSG) confirmed definite RBD and α-synucleinopathies in the FDRs of patients with RBD. | Baseline and 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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α-synucleinopathy, Neurodegeneration, Prodromal markers, REM sleep behavior disorder