Pinpointing the connection between Parkinson’s disease and REM sleep behaviour disorder

During REM (rapid eye movement) sleep cycles, most people are effectively paralyzed, so they don’t act out dreams. But a third of all people with Parkinson’s disease also have REM sleep behaviour disorder, a condition that removes that sleep paralysis and can cause people to lash out or hurt their bed partners. Her research is made possible through Parkinson Canada National Research program and funded in partnership with Fonds de recherche du Québec – Santé for $10,000 over 2 years.

“These people have more severe symptoms and a more severe disease progression,” says Jessie De Roy, a PhD student at the Université du Québec à Montréal. “They have a higher risk of dementia, more severe motor problems and more severe symptoms such as blood pressure problems.”

Other people who have this disorder but have not yet been diagnosed with Parkinson’s will likely go on to develop it. That means pinpointing the association between this sleep disorder and Parkinson’s may provide crucial cues for diagnosis and treatment.

De Roy uses brain scans, statistical models, and the results of sleep lab tests and psychological exams to identify structures in the brain and cellular pathways that are damaged in people with the sleep disorder. She compares the scans and other tests results in three groups of people: people with Parkinson’s who have the sleep disorder, people with Parkinson’s who do not have the sleep disorder, and healthy people without either diagnosis.

By analyzing the data from all three groups, De Roy hopes to develop a biomarker – a physiological sign that can predict who will develop dementia in Parkinson’s disease.

Ultimately, she hopes gaining a better understanding of the brains of people with this sleep disorder can lead to new treatments. Earlier identification of people who are likely to develop dementia could also help them access any new drugs or other therapies designed to protect people from developing Parkinson’s or prevent its progression.

De Roy chose to work on Parkinson’s disease because she’s determined to reduce the stigma associated with dementia and other non-motor symptoms of the illness.

“Parkinson’s is the second most common (neurodegenerative) disease after Alzheimer’s, but people don’t know much about it,” she says. “People think of Parkinson’s disease as a motor disease only, which it’s not.”

De Roy is also motivated by her grandfather’s difficult struggle with Parkinson’s. He was diagnosed too late for medication to help much, she says – another reason she’d like to find a biomarker to identify people earlier.

“There’s so much more to learn and to teach about this complex condition,” she says.