Sleep disorder linked to Alzheimer's, Parkinson's

A sleep disorder that causes people to act out their dreams is a predictor of brain diseases like Alzheimer's and Parkinson's, a new research has found.
"Rapid-eye-movement sleep behaviour disorder (RBD) is not just a precursor but also a critical warning sign of neurodegeneration that can lead to brain disease," said associate professor and lead author Dr John Peever from the University of Toronto in Canada.
"In fact, as many as 80 to 90 per cent of people with RBD will develop a brain disease," said Peever.
The disturbance occurs during the rapid-eye-movement (REM) stage of sleep and causes people to act out their dreams, often resulting in injury to themselves and/or bed partner, researchers said.

In healthy brains, muscles are temporarily paralysed during sleep to prevent this from happening.
"It's important for clinicians to recognise RBD as a potential indication of brain disease in order to diagnose patients at an earlier stage," said Peever.

"This is important because drugs that reduce neurodegeneration could be used in RBD patients to prevent (or protect) them from developing more severe degenerative disorders," Peever said.
His research examines the idea that neurodegeneration might first affect areas of the brain that control sleep before attacking brain areas that cause more common brain diseases like Alzheimer's.
Peever said he hopes the results of his study lead to earlier and more effective treatment of neurodegenerative diseases.

The research was published in the journal Trends in Neuroscience.