(Ivanhoe Newswire) -- An unusual sleep disorder could be a precursor to
dementia or Parkinsonís disease.
Patients with REM sleep behavior disorder have excessive muscle activity during
REM sleep -- often called the dream stage of sleep -- causing them to punch,
kick or cry out when they are in a deep sleep.
Of the 93 REM sleep behavior patients involved in the study, 26 developed a
neurodegenerative disease within five years. Doctors estimate the 10-year
disease development risk to be 41 percent and the 12-year risk to be 52 percent.
"The results may help us better understand how these neurodegenerative diseases
develop," study author Ronald B. Postuma, M.D., a sleep specialist from McGill
University in Montreal, Canada, was quoted as saying. "They also suggest that
there may be an opportunity for protecting against the progression to disease,
perhaps even preventing it before the symptoms can appear."
The patients involved in this study had no known cause of REM sleep behavior
disorder. In some cases, the condition can be caused by narcolepsy or rare
SOURCE: Neurology, published online Dec. 24, 2008