Acting out Dreams May Signal Dementia Decades Later

The strange sleep disorder that sounds fit for a murder mystery forecasts a not-so-bright future. REM sleep behavioral disorder is a parasomnia that makes people act out their dreams, sometimes violently. A single episode can be an early sign of degenerative brain disorders, such as Parkinson’s disease and dementia, researchers at the Mayo Clinic report.

Their findings were published in the August 2010 issue of Chest. The authors searched the Mayo Clinic’s 2002-2006 medical records for cases where patients developed neurodegerative symptoms at least 15 years after a RBD-related episode.

A total of 27 patients fit the researcher’s criteria. The onset of brain disorders occurred 25 years after symptoms of RBD, on average. Some patients took as long as 50 years to develop Parkinson’s or dementia.

Cases of dementia and Parkinson’s disease were nearly evenly split. One patient was diagnosed with multiple system atrophy. Some patients with dementia had dementia with Lewy bodies, which causes waking hallucinations.

People with RBD can act out their dreams because the brain fails to keep muscles still during REM sleep. Normally the brain paralyzes most muscles during the sleep stage where dreams usually occur.

REM sleep behavioral disorder can be dangerous to the dream or a bedpartner. A person with RBD can do anything from hitting or kicking to running out of the bedroom. AASM-accredited sleep centers offer effective treatment options for people with RBD.