REM sleep behavior disorder

Overview

Rapid eye movement (REM) sleep behavior disorder is a sleep disorder in which you physically act out vivid, often unpleasant dreams with vocal sounds and sudden, often violent arm and leg movements during REM sleep — sometimes called dream-enacting behavior.

You normally don't move during REM sleep, a normal stage of sleep that occurs many times during the night. About 20 percent of your sleep is spent in REM sleep, the usual time for dreaming, which occurs primarily during the second half of the night.

The onset of REM sleep behavior disorder is often gradual and it can get worse with time.

REM sleep behavior disorder may be associated with other neurological conditions, such as Lewy body dementia (also called dementia with Lewy bodies), Parkinson's disease or multiple system atrophy.

Symptoms

With REM sleep behavior disorder, instead of experiencing the normal temporary paralysis of your arms and legs (atonia) during REM sleep, you physically act out your dreams.

The onset can be gradual or sudden, and episodes may occur occasionally or several times a night. The disorder often worsens with time.

Symptoms of REM sleep behavior disorder may include:

• Movement, such as kicking, punching, arm flailing or jumping from bed, in response to action-filled or violent dreams, such as being chased or defending yourself from an attack
• Noises, such as talking, laughing, shouting, emotional outcries or even cursing
• Being able to recall the dream if you awaken during the episode

When to see a doctor

If you have any of the symptoms above or are experiencing other problems sleeping, talk to your doctor.

Causes

Nerve pathways in the brain that prevent muscles from moving are active during normal REM or dreaming sleep, resulting in temporary paralysis of your body. In REM sleep behavior disorder, these pathways no longer work and you may physically act out your dreams.

Risk factors

Factors associated with the development of REM sleep behavior disorder include:

• Being male and over 50 years old — however, more women are now being diagnosed with the disorder, especially under age 50, and young adults and children can develop the disorder, usually in association with narcolepsy, antidepressant use or brain tumors
• Having a certain type of neurodegenerative disorder, such as Parkinson's disease, multiple system atrophy, stroke or dementia with Lewy bodies
• Having narcolepsy, a chronic sleep disorder characterized by overwhelming daytime drowsiness
• Taking certain medications, especially newer antidepressants, or the use or withdrawal of drugs or alcohol

Recent evidence suggests that there may also be several specific environmental or personal risk factors for REM sleep behavior disorder, including occupational pesticide exposure, farming, smoking or a previous head injury.

Complications

Complications caused by REM sleep behavior disorder may include:

• Distress to your sleeping partner or other people living in your home
• Social isolation for fear that others may become aware of your sleep disruption
• Injury to yourself or your sleeping partner