Punching while sleeping, falling out of bed or scaring your partner during the night… These behaviors, which may seem anecdotal, are of great interest to neurologists. And for good reason: they could announce Parkinson’s disease, sometimes several decades in advance. For the University Hospital in Bonn, Germany, these are even very early warning signs to be taken seriously.
A phenomenon confirmed by neurologist and sleep specialist Michael Sommerauer, for whom these manifestations often correspond to paradoxical sleep behavior disorder (RPSD), also called isolated paradoxical sleep behavior disorder. According to him, “many people report very intense, often aggressive dreams in which they have to fight or flee”experienced during paradoxical sleep. These episodes are, according to the specialist,
“medically very relevant”because 80 to 95% of people affected by this disorder develop, within 10 to 15 years, Parkinson’s disease or dementia with Lewy bodies.
REM sleep behavior disorder: what patients experience
Faced with these blows, these screams or these sudden gestures during the night, the diagnosis is based on a video-polysomnography. This test records sleep, breathing and body movements. In people with isolated TCSP, specialists observe a
“loss of REM sleep atonia”. In other words, the muscles remain active when they should be completely relaxed. This sign makes it possible to distinguish TCSP from other sleep disorders, such as sleep apnea or certain deep sleep parasomnias.
Parkinson’s and related diseases: increased risk after TCSP
The figures put forward by Michael Sommerauer are based on large studies carried out on patients with confirmed isolated TCSP. A large majority of them develop Parkinson’s disease, dementia with Lewy bodies or multiple system atrophy over the years. However, these results concern patients for whom the diagnosis of TCSP is proven. They therefore do not mean that everyone who moves a little while sleeping will develop a neurodegenerative disease.
Thus, if Parkinson’s disease is generally diagnosed when the first motor disorders are already well established, silent changes in the nervous system can appear up to 30 years before diagnosis, according to Michael Sommerauer. During this so-called prodromal phase, TCSP constitutes one of the most important markers of the onset of Parkinson’s disease or another synucleinopathy.
New tools to detect the disease earlier
At the University Hospital in Bonn, Germany, a team supported by the European Research Council is currently developing a system capable, “using a tablet, you can record motor abnormalities in a few minutes directly in the general practitioner’s office”explains Michael Sommerauer. According to him, “this could represent a real breakthrough for early diagnosis”.
Researchers are also testing cognitive stimulation programs on smartphones and tablets, as well as “motivating app that encourages people with PTSD to be more active”.
For Michael Sommerauer, these digital tools “could in the future constitute a real alternative or complement to drug treatments, particularly as long as there are not yet specific drugs for the early stages of the disease”. He adds that “this also applies to Parkinson’s disease”recalling that “Parkinson’s disease is a disease of movement, and we have very good data showing that physical activity can slow its progression”.