Rapid eye movement behavior disorder
Encyclopedia
Rapid eye movement sleep behaviour disorder (RBD) is a sleep disorder
(more specifically a parasomnia
) that involves abnormal behaviour during the sleep phase with rapid eye movement (REM sleep). It was first described in 1986.
The major and arguably only abnormal feature of RBD is loss of muscle atonia (paralysis
) during otherwise intact REM sleep. This is the stage of sleep in which most vivid dream
ing occurs. The loss of motor inhibition leads to a wide spectrum of behavioural release during sleep. This extends from simple limb twitches to more complex integrated movement, in which sufferers appear to be unconsciously
acting out their dreams. These behaviours can be violent in nature and in some cases will result in injury to either the patient or their bed partner.
and Lewy Body Dementia.
is most effective with a 90% success rate, how this drug works to restore REM atonia is unclear, however it is thought to suppress muscle activity, rather than directly restoring atonia. Melatonin
is also effective and can also be prescribed as a more natural alternative. For those with Parkinson's and RBD, Levodopa is a popular choice. Pramipexole
is another drug which can be an effective treatment option.
In addition to medication, it is wise to secure the sleeper's environment in preparation for episodes by removing potentially dangerous objects from the bedroom and either place a cushion round the bed or moving the mattress to the floor for added protection against injuries.
It is best to maintain a normal sleep schedule, and avoid sleep deprivation. Do this by keeping track of any sleepiness you may have. It is also crucial to avoid alcohol consumption and certain medications. To keep your RBD under control, regulate your neurologic symptoms and treat any other sleep disorders than might interfere with your sleep. Sleep deprivation, alcohol, certain medications, and other sleep disorders can all increase RBD, and should be avoided if possible.
or androgenic factors. The mean age of onset is estimated to be about 60 years.
Various conditions are very similar to RBD in that sufferers exhibit excessive sleep movement and potentially violent behaviour. Such disorders include sleepwalking
and sleep terrors, which are associated with other stages of sleep, nocturnal seizures and obstructive sleep apnea
which can induce arousals from REM sleep associated with complex behaviors. Because of the similarities between the conditions, polysomnography
plays an important role in confirming RBD diagnosis.
It is now apparent that RBD appears in association with a variety of different conditions. Narcolepsy
has been reported as a related disorder. Both RBD and narcolepsy involve dissociation of sleep states probably arising from a disruption of sleep control mechanisms. RBD has also been reported following cerebrovascular accident and neurinoma (tumour), indicating that damage to the brain stem
area may precipitate RBD. RBD is usually chronic
, however may be acute and sudden in onset if associated with drug treatment
or withdrawal
(particularly with alcohol withdrawal) 60% of RBD is idiopathic
. This includes RBD that is found in association with conditions such as Parkinson’s disease and dementia
with Lewy bodies, where it is often seen to precede the onset of neurodegenerative disease. RBD has been associated with autism . Monoamine oxidase inhibitors, tricyclic antidepressants, serotonergic synaptic reuptake inhibitors, and noradrenergic antagonists can induce or aggravate RBD symptoms and should be avoided in patients with RBD.
Sleep disorder
A sleep disorder, or somnipathy, is a medical disorder of the sleep patterns of a person or animal. Some sleep disorders are serious enough to interfere with normal physical, mental and emotional functioning...
(more specifically a parasomnia
Parasomnia
For the 2008 horror film, see Parasomnia Parasomnias are a category of sleep disorders that involve abnormal and unnatural movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping, between sleep stages, or during arousal from sleep...
) that involves abnormal behaviour during the sleep phase with rapid eye movement (REM sleep). It was first described in 1986.
The major and arguably only abnormal feature of RBD is loss of muscle atonia (paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...
) during otherwise intact REM sleep. This is the stage of sleep in which most vivid dream
Dream
Dreams are successions of images, ideas, emotions, and sensations that occur involuntarily in the mind during certain stages of sleep. The content and purpose of dreams are not definitively understood, though they have been a topic of scientific speculation, philosophical intrigue and religious...
ing occurs. The loss of motor inhibition leads to a wide spectrum of behavioural release during sleep. This extends from simple limb twitches to more complex integrated movement, in which sufferers appear to be unconsciously
Unconsciousness
Unconsciousness is the condition of being not conscious—in a mental state that involves complete or near-complete lack of responsiveness to people and other environmental stimuli. Being in a comatose state or coma is a type of unconsciousness. Fainting due to a drop in blood pressure and a...
acting out their dreams. These behaviours can be violent in nature and in some cases will result in injury to either the patient or their bed partner.
Symptoms
RBD is characterised by the dreamer acting out his or her dreams. These dreams often involve kicking, screaming, punching, grabbing, and even jumping out of bed. When awoken, one can usually recall the dream they were having which will match the actions they were performing, but they will not be aware that they were moving. In a normal sleep cycle, you may experience REM sleep every1 1/2 to 2 hours every night. Which means RBD episodes may occur up to four times a night. In a rare case, they may only happen once a week or once a month. Episodes occur more towards the morning hours because that is when REM sleep is more frequent. The actions in an episode can result in injuries to oneself or one's bed partner. People can also respond to other people while sleeping and not even know it. This causes them to be aware of things while they're sleeping, which can result in sleep deprivation.Causes
Rapid eye movement behaviour disorder occurs when there is a loss of normal voluntary muscle atonia during REM sleep resulting in motor behaviour in response to dream content. It can be caused by adverse reactions to certain drugs or else during drug withdrawal; however it is most often associated with the elderly and in those with neurodegenerative disorders such as Parkinson disease, and other neurodegenerative diseases for example multiple system atrophyMultiple system atrophy
Multiple system atrophy is a degenerative neurological disorder. MSA is associated with the degeneration of nerve cells in specific areas of the brain. This cell degeneration causes problems with movement, balance and other autonomic functions of the body such as bladder control or blood pressure...
and Lewy Body Dementia.
Treatment
RBD is treatable. Various medications are prescribed for RBD based on varying symptoms. Low doses of clonazepamClonazepam
Clonazepamis a benzodiazepine drug having anxiolytic, anticonvulsant, muscle relaxant, and hypnotic properties. It is marketed by Roche under the trade name Klonopin in the United States and Rivotril in Australia, Brazil, Canada and Europe...
is most effective with a 90% success rate, how this drug works to restore REM atonia is unclear, however it is thought to suppress muscle activity, rather than directly restoring atonia. Melatonin
Melatonin
Melatonin , also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes...
is also effective and can also be prescribed as a more natural alternative. For those with Parkinson's and RBD, Levodopa is a popular choice. Pramipexole
Pramipexole
Pramipexole is a non-ergoline dopamine agonist indicated for treating early-stage Parkinson's disease and restless legs syndrome...
is another drug which can be an effective treatment option.
In addition to medication, it is wise to secure the sleeper's environment in preparation for episodes by removing potentially dangerous objects from the bedroom and either place a cushion round the bed or moving the mattress to the floor for added protection against injuries.
It is best to maintain a normal sleep schedule, and avoid sleep deprivation. Do this by keeping track of any sleepiness you may have. It is also crucial to avoid alcohol consumption and certain medications. To keep your RBD under control, regulate your neurologic symptoms and treat any other sleep disorders than might interfere with your sleep. Sleep deprivation, alcohol, certain medications, and other sleep disorders can all increase RBD, and should be avoided if possible.
Epidemiology
The most comprehensive assessment so far has estimated RBD prevalence to be about 0.5% in individuals aged 15 to 100. It is far more common in males: most studies report that only about a tenth of sufferers are female. This may partially be due to a referral bias, as violent activity carried out by men is more likely to result in harm and injury and is more likely to be reported than injury to male bed partners by women, or it may reflect a true difference in prevalence as a result of geneticGenetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
or androgenic factors. The mean age of onset is estimated to be about 60 years.
Various conditions are very similar to RBD in that sufferers exhibit excessive sleep movement and potentially violent behaviour. Such disorders include sleepwalking
Sleepwalking
Sleepwalking, also known as somnambulism, is a sleep disorder belonging to the parasomnia family. Sleepwalkers arise from the slow wave sleep stage in a state of low consciousness and perform activities that are usually performed during a state of full consciousness...
and sleep terrors, which are associated with other stages of sleep, nocturnal seizures and obstructive sleep apnea
Sleep apnea
Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low...
which can induce arousals from REM sleep associated with complex behaviors. Because of the similarities between the conditions, polysomnography
Polysomnography
Polysomnography , also known as a sleep study, is a multi-parametric test used in the study of sleep and as a diagnostic tool in sleep medicine. The test result is called a polysomnogram, also abbreviated PSG...
plays an important role in confirming RBD diagnosis.
It is now apparent that RBD appears in association with a variety of different conditions. Narcolepsy
Narcolepsy
Narcolepsy is a chronic sleep disorder, or dyssomnia, characterized by excessive sleepiness and sleep attacks at inappropriate times, such as while at work. People with narcolepsy often experience disturbed nocturnal sleep and an abnormal daytime sleep pattern, which often is confused with insomnia...
has been reported as a related disorder. Both RBD and narcolepsy involve dissociation of sleep states probably arising from a disruption of sleep control mechanisms. RBD has also been reported following cerebrovascular accident and neurinoma (tumour), indicating that damage to the brain stem
Brain stem
In vertebrate anatomy the brainstem is the posterior part of the brain, adjoining and structurally continuous with the spinal cord. The brain stem provides the main motor and sensory innervation to the face and neck via the cranial nerves...
area may precipitate RBD. RBD is usually chronic
Chronic (medicine)
A chronic disease is a disease or other human health condition that is persistent or long-lasting in nature. The term chronic is usually applied when the course of the disease lasts for more than three months. Common chronic diseases include asthma, cancer, diabetes and HIV/AIDS.In medicine, the...
, however may be acute and sudden in onset if associated with drug treatment
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...
or withdrawal
Withdrawal
Withdrawal can refer to any sort of separation, but is most commonly used to describe the group of symptoms that occurs upon the abrupt discontinuation/separation or a decrease in dosage of the intake of medications, recreational drugs, and alcohol...
(particularly with alcohol withdrawal) 60% of RBD is idiopathic
Idiopathic
Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...
. This includes RBD that is found in association with conditions such as Parkinson’s disease and dementia
Dementia
Dementia is a serious loss of cognitive ability in a previously unimpaired person, beyond what might be expected from normal aging...
with Lewy bodies, where it is often seen to precede the onset of neurodegenerative disease. RBD has been associated with autism . Monoamine oxidase inhibitors, tricyclic antidepressants, serotonergic synaptic reuptake inhibitors, and noradrenergic antagonists can induce or aggravate RBD symptoms and should be avoided in patients with RBD.