An article appearing in the current issue of Brain, the Oxford Journal of Neurology, reveals that researchers at the Mayo Clinic have found a correlation between REM behavior disorder and Parkinson's or Lewy body dementia.
REM (rapid eye movement) sleep occurs in brief spurts of increased activity in the brain and is considered the dreaming stage of sleep. While in REM sleep, the eyes can be seen moving rapidly beneath the eyelids. Most dreaming occurs during REM and the body is essentially paralyzed to avoid the “acting out” of dreams.
RBD is rapid eye movement behavioral disorder. It's characterized by the acting out of violent dreams during REM sleep. Sometimes the victim of RBD will shout or strike out during an episode. This can become so violent that bed partners may be injured.
Research shows that patients who suffer from RBD may later develop Parkinson’s disease or a less common but related disease called Lewy body dementia. Parkinson's disease is a degenerative disorder of the central nervous system that impairs motor skills and speech. It can occur with or without dementia. Lewy body dementia is caused by damage in the brain. The name derives from the deposits seen microscopically in the brain after death which contain damaged nerve cells. Lewy bodies were named for the doctor who discovered them.
Although RBD victims are usually older males, the disorder can strike younger people and women as well. Mayo clinic researchers followed these cases for many years and saw many as two-thirds of them develop symptoms of Parkinson's disease or Lewy body dementia.
"Our data suggest that many patients with idiopathic (not associated with any other neurologic symptoms) RBD may be exhibiting early signs of an evolving neurodegenerative disease, which in most cases appear to be caused by some mishap of the synuclein protein," says Bradley Boeve, M.D., Mayo Clinic neurologist and lead author of the article.
Synuclein protein is implicated in the pathogenesis of both Parkinson's disease and Lewy body dementia, as well.
Unfortunately, many cases of RBD go undetected because the victim sleeps alone, the condition is tolerated, or in some cases, misdiagnosed.
Published On: May 17, 2007