Rapid eye movement sleep behavior disorder
 | This article needs additional citations for verification. (July 2007) |
| Rapid eye movement sleep behavior disorder | |
|---|---|
| Specialty | Neurology  |
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 dreaming 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.
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 every 1 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.[1] 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. [2]
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[3] for example multiple system atrophy and Lewy Body Dementia.
Treatment
RBD is treatable. Various medications are prescribed for RBD based on varying symptoms. Low doses of clonazepam 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.[4]
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.[2][5][6] 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 that might interfere with your sleep. Sleep deprivation, alcohol, certain medications, and other sleep disorders can all increase RBD, and should be avoided if possible.[7]
Epidemiology
The most comprehensive assessment so far has estimated RBD prevalence to be about 0.5% in individuals aged 15 to 100.[8] 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 genetic or androgenic factors. The mean age of onset is estimated to be about 60 years.[9]
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 [citation needed]. 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.
In non-humans
RBD has been diagnosed in non-humans, specifically, dogs.[10]
References
- ^ Schutte-Rodin, Sharon. "REM Sleep Behavior Disorder". yoursleep.aasmnet.org. American Academy of Sleep Medicine. Retrieved 1 October 2011.
- ^ a b "REM Sleep Behavior Disorder". Mayo Clinic. Retrieved 2010-01-02.
- ^ Gugger, JJ.; Wagner, ML. (2007). "Rapid eye movement sleep behaviour disorder". Ann Pharmacother. 41 (11): 1833–41. doi:10.1345/aph.1H587. PMID 17925503.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Paparrigopoulos, TJ. (2005). "REM sleep behaviour disorder: clinical profiles and pathophysiology". Int Rev Psychiatry. 17 (4): 293–300. doi:10.1080/09540260500104540. PMID 16194802.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Ferini-Strambi, L.; Zucconi, M. (2000). "REM sleep behaviour disorder". Clin Neurophysiol. 111 Suppl 2: S136-40. PMID 10996567.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Boeve, BF.; Silber, MH.; Ferman, TJ. (2004). "REM sleep behaviour disorder in Parkinson's disease and dementia with Lewy bodies". J Geriatr Psychiatry Neurol. 17 (3): 146–57. doi:10.1177/0891988704267465. PMID 15312278.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Schutte-Rodin, Sharon. "REM Sleep Behavior Disorder". yoursleep.aasmnet.org. American Academy of Sleep Medicine. Retrieved 1 October 2011.
- ^ Ohayonet M.M. et al. (1997). Violent behaviour during sleep. Journal of Clinical Psychiatry 58: 369–76.
- ^ Olson EJ et al. (2000). Rapid eye movement sleep behaviour disorder: demographic, clinical and laboratory findings in 93 cases. Brain 123: 331–39. PMID 10648440
- ^ Carey, Sarah (2001-02-13). "Dog with Rare Sleeping Disorder Sent Home After Unique Diagnosis at UF's Veterinary Medical Teaching Hospital". University of Florida. Retrieved 2010-01-02.