A novel test (RT-QuIC) to differentiate between two types of REM Behavioural Disorder (RBD) - pRBD (which is a potential indicator of future development of Parkinson's Disease) and iRBD (which is not thought to be)

Plain English summary of protocol

Background and study aims
Rapid Eye Movement Sleep Behaviour Disorder (RBD) is a sleep disorder in which people act out their dreams. Previous studies have found a high conversion rate from RBD to subsequent neurodegenerative disease, with the majority of patients developing one of the α-synucleinopathies (Parkinson’s disease, multiple system atrophy, Lewy body dementia). As not all RBD patients go on to develop a neurodegenerative disease (40 - 80.8% in 16 to 25 years of follow-up), and RBD only presents as a comorbidity in a percentage of patients with α-synucleinopathies (30% of Parkinson’s disease patients have RBD), it is important to identify factors which robustly provide prognostic data on the clinical course of RBD. The aim of this study is to develop and validate a test for the detection of pathological protein (α-syn RT-QuIC) that can be used to differentiate between cases of RBD that subsequently progress to a neurodegenerative disorder such as Parkinson's disease and those that do not.

Who can participate?
Patients aged over 18 with a diagnosis of RBD

What does the study involve?
All data is collected in one 90-minute appointment, which takes place at the Wellcome Trust Clinical Research Facility (WTCRF) at either Royal Infirmary of Edinburgh or Western General Hospital Edinburgh. The appointment involves a clinical examination and interview, blood sampling and cerebrospinal fluid (CSF) sampling via lumbar puncture. Participants are interviewed with regards to their lifestyle, medical history and comorbidities. Participants are asked to fill out sleep diaries and questionnaires relating to their sleep. All patients are examined clinically regarding motor function and anosmia. Markers of autonomic dysfunction are also tested for using simple techniques such as an orthostatic standing test. Any individuals who have already developed PD are interviewed with regards to their neurodegenerative presentation, e.g. response to drug treatment.

What are the possible benefits and risks of participating?
Whilst there is no direct benefit to the individual participant, their participation in the study will help to develop a test which may benefit many other patients with RBD in the future. Time burden to the patient is minimal, with only a single 90-minute study visit required. Blood sampling is generally well-tolerated. Minor discomfort and bruising may occur at the needle site but should self-resolve quickly. Some individuals may feel dizzy or faint, and can lie down during the procedure. A lumbar puncture is generally a safe procedure and serious side effects are uncommon. The most common side effects include headaches, which can last for up to a week and can be relieved using over-the-counter painkillers, and swelling and lower back pain where the needle was inserted, which should get better after a few days and is normally nothing to worry about. The questionnaires used contain personal questions which some individuals may find intrusive or uncomfortable to answer, though all information is required purely to make a complete clinical assessment.

Where is the study run from?
University of Edinburgh/NHS Lothian Royal Infirmary (UK)

When is the study starting and how long is it expected to run for?
January 2020 to September 2023 (updated 21/04/2020, previously: June 2023)

Who is funding the study?
Weston Brain Institute (UK)

Who is the main contact?
Dr Renata Riha
rriha1@staffmail.ed.ac.uk

Contact information

Study information

Eligibility

Locations

Countries of recruitment

• Scotland
• United Kingdom

Study participating centres

Sponsor information

Funders

Funder type

Research organisation

Results and Publications

Study outputs

Editorial Notes

17/10/2022: The public contact has confirmed that this trial did not commence due to the pandemic. It now cannot be undertaken due to lack of resources.
03/09/2021: The recruitment start date was changed from 01/09/2021 to 01/10/2021.
14/05/2021: The recruitment start date was changed from 01/06/2020 to 01/09/2021.
28/07/2020: The ethics approval was added.
21/04/2020: The following changes were made to the trial record:
1. The recruitment start date was changed from 01/03/2020 to 01/06/2020.
2. The recruitment end date was changed from 01/09/2022 to 01/12/2022.
3. The overall end date was changed from 01/06/2023 to 01/09/2023.
4. The intention to publish date was changed from 01/06/2023 to 01/09/2024.
5. The plain English summary was updated to reflect these changes.
6. Due to current public health guidance, recruitment for this study has been paused.
14/01/2020: Trial's existence confirmed by the Weston Brain Institute.