Investigating RBD using EEG and Additional Multi-Modal Measures
Research type
Research Study
Full title
Integrating EEG to Stratify Severity Progression and Neurodegenerative Risk in REM Sleep Behaviour Disorder (RBD)
IRAS ID
262961
Contact name
Michal Rolinski
Contact email
Sponsor organisation
University of Bristol
Duration of Study in the UK
3 years, 5 months, 1 days
Research summary
Summary of Researh
A high percentage of people with REM-Sleep Behaviour Disorder (RBD) will go on to develop one of the neurodegenerative diseases known as the ‘alpha-synucleinopathies’, such as Parkinson’s disease (PD). RBD therefore is one of the earliest warning signs that an individual is developing PD, and can precede PD development by up to 15 years. Despite increasing awareness and research into RBD and its connection with neurodegeneration, to date there are no clinically-approved tools for RBD prognosis and symptom-tracking remains precedent. There is also no way to tell how far along the degenerative process an individual with RBD is. \n\nOne way to assess the global effects of neurodegenerative processes is using electroencephalography (EEG), which in a non-invasive, painless way to record electrical brain activity. Given the clinical availability of EEG systems, and the development and commercialisation of wireless EEG headsets, this project focuses upon identifying EEG signatures of RBD. We will use EEG to investigate changes in brain activity associated with RBD across wake, sleep and ‘active’ behavioural task states. This is the first high-density EEG investigation in RBD patients, allowing for increased spatial resolution of brain activity compared to previous studies. \n\nWe propose an observational study, wherein high-density EEG is combined with deep phenotyping methods in RBD, Parkinson’s disease and matched controls. Baseline measures of cognitive, motor and psychological function will be collected in an initial clinical appointment. Participants will then undergo a week of continuous physiological (heart rate, high-density EEG) and motor function data capture in their home environment. The same home recording protocol will be repeated 12 months later in the RBD and matched control participants.\n\nWe hope that capturing many aspects of the participants will allow us to identify small, subtle changes associated with RBD which may previously have been overlooked. Machine learning will be enlisted analysis of baseline measures in order to classify RBD individuals according to the extent of neurodegeneration. 12-month follow up data will be analysed to determine the rate of subtle disease progression and as a prognostic marker for RBD course.\nSummary of Results
The goal of the STREEM study was to identify early biomarkers of Parkinson’s disease, which might be useful for predicting whether a person with REM Sleep Behavioural Disorder (RBD) might go on to develop Parkinson’s disease.Who participated in the study?
In total, 52 participants were recruited to the study. There were three groups of participants: people with RBD, people with Parkinson’s disease, and ‘Control’ participants (people who did not have RBD or Parkinson’s disease).What are the main findings of the study?
In the search for biomarkers, a large number of bodily functions were investigated including sense of smell, motor function, eye movements and brain activity. We wanted to see which of these functions were different between Control, RBD and Parkinson’s disease participants. The results from these investigations are summarised below for the three study groups.• The RBD and Parkinson’s disease groups had a reduced sense of smell, higher levels of constipation and higher levels of depression compared to the Control group. These three measures may be the most useful for predicting if someone with RBD will develop Parkinson’s disease.
• People with RBD were often unaware that their sense of smell was reduced. This result and the consequences of this are discussed in our recent publication:
Inaccurate self-report of olfactory dysfunction in REM Sleep Behaviour Disorder and implications for prognosis (Roguski et al. 2022).
https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fu2790089.ct.sendgrid.net%2Fls%2Fclick%3Fupn%3DXv3JSvJ-2B3M71ppf7N9agbVwdcg6EH26jlSvYTYfcP2k3qrmaZg3HArvm5V-2Fy8Mew5t3ScmgY9WQEdCH3vGvqVQ-3D-3DkAvI_E1aO2-2BZlVOSJJV-2FajQqskegTd6IRomHYTi-2Fbt8SH3YLrKs96fS8dJxtmdO2HxVh5gQj76Lb8hEQxhVituV5hVOw-2FXyDxcMuO2l8B-2B9RdIl6gPvprlOuNbWHopJm5cPvszezlrGb1xFBkRwsdQurMpUoHlU4Q7aocFKPxsj6vJOYRfQjnkHQES83uDQj-2BpAB5kFfkK1TrJzyFyR98TIfzLg-3D-3D&data=05%7C01%7Capprovals%40hra.nhs.uk%7C0abcab77c7274e35c65508db3dad59ea%7C8e1f0acad87d4f20939e36243d574267%7C0%7C0%7C638171586963858729%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=nGfz%2FQhIZa7XY2hnynk1Zydbf93wosTDQWe2YZt2U0g%3D&reserved=0• Small differences were found between the Control and Parkinson’s disease groups for measures including heart rate variability during sleep and wake, brain activity during sleep and eye movements. These differences were not significant but provide an interesting foundation for future research into Parkinson’s disease biomarkers.
With these findings, we concluded that simple, standardised clinical tests such as testing sense of smell are useful when determining if someone with RBD will develop Parkinson’s disease. Our future work aims to use these findings to promote standardised clinical testing of people with RBD to help track their symptoms over time.
REC name
South West - Central Bristol Research Ethics Committee
REC reference
19/SW/0103
Date of REC Opinion
17 Jun 2019
REC opinion
Further Information Favourable Opinion