Rapid Eye Movement Sleep Behavior Disorder
People with rapid eye movement (REM) sleep behavior disorder react physically to what they are dreaming. During episodes, a person vocalizes or screams, and/or engages in complex and sometimes violent motor behaviors while in a REM state of sleep. These actions, known as “dream enacting behavior,” typically reflect the content of action-filled or violent dreams in which the person is being attacked or trying to escape danger.
During REM sleep, people typically experience vivid dream imagery but also a loss of muscle tone similar to paralysis, known as atonia. Because of this, most people are not able to physically respond to their dreams. People with REM sleep behavior disorder, however, can enter REM sleep without atonia, enabling them to act on their dream imagery.
Episodes of REM sleep behavior disorder usually start more than 90 minutes after a person has fallen asleep, when they are in a REM state. Their screaming, moaning, or singing is typically loud, emotional, and may include profanity, and their physical behaviors can include running, punching, hitting, jumping out of bed, and kicking. Episodes can indeed be dangerous: A person may throw themselves out of bed, causing injury or concussion, or hurt their spouse or partner. Once the person wakes up, they are usually alert and aware; they may be frightened or sweaty, but they can remember the content of their dreams.
For a diagnosis of REM sleep behavior disorder to be made, this behavior must cause significant distress or impairment in some important area of daily life, including injury to oneself or to one’s bed partner during sleep. In making a diagnosis and recommending treatment, a specialist will be equally concerned about the frequency of episodes and their violent nature.
Is REM sleep behavior disorder a type of sleepwalking?
No. Somnambulism, or sleepwalking, typically takes place during non-REM stages of sleep and generally has no connection to the content of one’s dreams. (It is also much less commonly violent.) Even if sleepwalking does occur during a dream, it usually does not involve acting it out, and unlike with REM sleep behavior disorder, the sleepwalker typically does not remember the dream (or that they were sleepwalking).
How does REM sleep behavior disorder affect a person’s social life?
It can have a significant effect until a person seeks treatment. Embarrassment over episodes can impair social relationships, as individuals could avoid any situations in which others could discover their condition, such as vacation travel, overnight visits to friends, and sleeping with new sex partners. This avoidance can lead to painful social isolation.
What do people with REM sleep behavior disorder dream about?
The vast majority of dreams that trigger episodes of the disorder are violent, research suggests, including attacks by unknown assailants or by animals like tigers, panthers, wolves, dogs, or bears. Most of the time the patient has not experienced similar events in real life. The patients often remember the content of their dreams when they awaken.
In many cases of REM sleep behavior disorder, the cause is unknown. In some cases, an individual’s reaction to prescription medication, including some anti-depressants and beta-blockers, can trigger the disorder. It is not known, however, whether these medications directly cause symptoms or activate an underlying predisposition to develop the disorder.
In other cases, the disorder may be associated with damage to parts of the central nervous system as can occur with multiple sclerosis; or with the accumulation of abnormal molecules in the nervous system as can occur in Parkinson's disease, multiple system atrophy, major or mild neurocognitive disorder with Lewy bodies, or Alzheimer’s disease.
How prevalent is REM sleep behavior disorder?
Less than 0.5 percent of the general population is believed to have REM sleep behavior disorder, but the prevalence is higher in those with certain neurocognitive disorders, and it may be present in approximately 30 percent of people living with narcolepsy.
Who is most likely to have REM sleep behavior disorder?
The condition most commonly occurs in men older than 50.
REM sleep behavior disorder is usually diagnosed by a sleep specialist, often after an overnight sleep test. Treatment includes medication and changes in the patient’s sleep environment to protect themself and their partner. Medications such as Klonopin and melatonin have both been shown to improve symptoms, but as with any medication, they should be taken only as prescribed and monitored carefully for side effects.
How can someone with REM sleep behavior disorder make their bed and bedroom safer for themselves and their partner?
A sleep specialist may suggest adaptations in a patient’s sleep environment including:
* Padding the floor around the bed with a mattress or pillows.
* Padding the corners of nearby furniture.
* Extra window protection.
* The removal of dangerous objects, such as guns or sharp objects, from the bedroom area.
After a diagnosis, a specialist may also suggest that a person experiencing the disorder sleep in a separate room from their bed partner until treatment brings symptoms under control.
Can REM sleep behavior disorder be a sign of other underlying conditions?
Yes. Research has uncovered a significant association between the onset of REM sleep behavior disorder and the emergence—a decade or more later—of underlying neurodegenerative disorders such as Parkinson's disease, multiple system atrophy, or major or mild neurocognitive disorder with Lewy bodies. A patient’s doctor is likely to encourage them to be regularly checked for these serious neurological disorders.