Normally when we go into REM sleep, we become paralyzed. The only muscles that continue to work at routine levels are the diaphragm and the eye muscles. However, some individuals who lack this inhibition and can move while dreaming. In these folks, dreams are frequently violent and result in harm to themselves or a bed partner.
We know that this disorder seems to be more common in middle-aged men, although by no means is it exclusive to them. We also know that up to 40 percent of these people, when followed over a period of time, go on to develop Parkinson’s disease or Parkinson-like disorders such as dementia with Lewy bodies or multiple system atrophy.
I devote a chapter of my new book Sleep Soundly Every Day, Feel Fantastic Every Night to the topic of REM Behavior Disorder (RBD). RBD is a very real problem for numerous Americans, as well as an unfortunate source of embarrassment. I make it a point to ask all of my new patients “Have you ever been known to act out your dreams?” It never ceases to amaze me as to how many say yes.
Fortunately, we may now have the answer as to why this sleep disorder is so commonly followed by Parkinson’s disease. Scientists presented the results of an eight-year study at the 2014 annual meeting of the Society of Nuclear Medicine and Molecular Imaging. Twenty-one patients with REM Behavior Disorder, but no evidence of Parkinson’s, were followed using specialized brain scans called single photon emission computed tomography (SPECT). These scans allow clinicians to view biological activity, as opposed to just the structure of the brain. Ten of these individuals showed dopamine abnormalities, 7 of which developed Parkinson’s disease or similar neurodegenerative disorders 8 years later.
I believe this discovery signals a very important breakthrough for those with RBD. Up until now, all I could tell my patients with this common sleep-related disorder was that they had a 30 to 40 percent chance of developing Parkinson’s. However, now using techniques such as SPECT, we may be able to accurately predict who is most at risk for developing Parkinson’s. Just as important is the research currently being conducted on medications that may halt the progression of Parkinson’s, when discovered in the early stages. Ultimately, early recognition of RBD might go a long way to decreasing this disabling and deadly disease. If you or a loved one acts out dreams, it is imperative to bring it to the attention of your health care provider.
Robert Rosenberg, DO
APR