Aug 1, 2011 15:03 GMT  ·  By

People who have been professionally diagnosed with REM sleep behavior disorders are at a higher risk of developing Parkinson’s disease later in life. These conclusions belong to a new European study.

Experts at the IDIBAPS (Institut d’Investigacions Biomèdiques August Pi i Sunyer), in Spain, say that the correlation was made clear in two investigations conducted in recent times. This is the third study on the issue conducted over the past 5 years alone.

Details of the work appear in the current issue of the esteemed scientific journal Lancet Neurology. In it, scientists define rapid-eye movement (REM) sleep behavior disorders as conditions where people suffer from horrible nightmares.

Usually, patients in these circumstances have the tendency to dream that they are being attack and/or pursued. This leads them to scream, punch, cry or kick during sleep. Apparently, this behavior is detrimental to neural health, PsychCentral reports.

Parkinson’s disease is a neurodegenerative disease, a form of dementia that affects increasingly large numbers of seniors. It manifests itself through slowness of movement, rigidity and shaking in its earliest stages, and through cognitive and behavioral problems later on.

Interestingly, past studies have evidenced that people who suffer from sleep disturbances tend to be at a higher risk of developing this condition. In fact, experts estimate that nearly 45 percent of patients suffering from a REM sleep behavior disorder go on to develop Parkinson’s.

Scientists have determined that the disorders basically affect the brain's dopamine system. By using brain single-photon emission computed tomography (SPECT) scans, it may soon become possible to determine REM SBD patients who are at risk of developing dementia.

In patients with REM sleep behavior disorders, average dopamine levels in the brain decrease considerably over the span of a few short years. This rapid decline can be used as a biomarker for Parkinson’s, allowing experts to detect the onset of the neurodegenerative condition.

If it is caught in time, Parkinson’s can be treated to some extent, although no definitive cure yet exists. A great deal of emphasis is currently placed on developing methods of detecting this condition as early as possible, so as to reduce costs associated with treating it.

The new study indicates that neuroprotective drugs should be developed in a such a way that they prevent dopamine levels in the brain from dropping constantly. If such a chemical is developed, it could be used to address other disorders characterized by low dopamine levels.