REM Sleep Behavior Disorder: Causes, Symptoms & Treatment

REM sleep behavior disorder (RBD) is a sleep disorder in which complex movements occur during the dream phase. The sufferer reacts to certain dream content by acting aggressively. RBD is often the precursor of Parkinson’s disease, Lewy body dementia, or MSA (multisystem atrophy).

What is REM sleep behavior disorder?

REM sleep behavior disorder is a parasomnia (behavioral abnormality during sleep) that occurs during REM sleep. It involves vivid dreams, often with aggressive content, in which the affected person reacts by hitting, kicking or screaming. Often the person in bed is attacked and even injured as a result. Self-injury also occurs. The dream is lived out. After awakening, however, there is no memory. The disorder is also known as Schenck syndrome or RBD (rapid eye movement sleep behavior disorder). Men are affected in more than 90 percent of cases. RBD usually occurs between the ages of 40 and 70. In the majority of cases (over 80 percent), affected individuals are over 60 years of age. Very rarely, individuals under the age of 40 have REM sleep behavior disorder.

Causes

The cause of REM sleep behavior disorder is thought to be synucleinopathy. This is a deposition of misfolded alpha-synuclein within neurons in the brainstem. Synuclein is responsible for the formation of dopamine. As a result of a genetic modification of this protein, misfolding can occur, destroying its secondary structure to form insoluble protein complexes. On the one hand, this reduces the formation of dopamine and, on the other hand, these deposits block important sections of the brain stem. In the process, the motor activity-inhibiting processes are switched off in the brain during sleep. This in turn leads to the fact that the dream contents can be lived out with the help of movements. Since synucleins are simultaneously responsible for dopamine formation, their misfolding leads to a reduction in dopamine production. This is why REM sleep behavior disorder is often an accompanying symptom of Parkinson’s disease. This disorder can develop before or during Parkinson’s disease. Because the resulting deposits damage certain areas of the brain, Lewy body dementia often develops as a result of RBD. In rarer cases, multisystem atrophy (MSA) develops.

Symptoms, complaints, and signs

REM sleep behavior disorder manifests as increased motor activity during the REM sleep phase. Patients experience violent dreams that mainly involve attacks by insects, animals, or humans. The affected person defends himself by hitting, kicking and screaming. The movements are performed because motor inhibition is abolished by the misfolded alpha synuclein. The movements are complex, with no leaving the bed, unlike sleepwalking. The affected person’s behavior during sleep, including his speech and cries, is not typical of his behavior during wakefulness. The affected person also cannot remember the dream after waking up. When waking up, the waking action and the dream are mixed. The result is danger to others and danger to oneself through violent actions. However, the other phases of sleep are calm and subject to normal rhythm. The frequency of sleep abnormalities ranges from once a week to several times a night. In many cases, RBD is an accompanying symptom of Parkinson’s disease. Often, REM sleep behavior disorder occurs idiopathically and is the first symptom of Parkinson’s disease or Lewy body dementia. Sometimes the disorder is also associated with symptoms of cognitive impairment.

Diagnosis and course of the disease

REM sleep behavior disorder can be identified using a variety of diagnostic procedures. For this purpose, relatives are interviewed as part of an external history. The patient also provides a self-assessment of symptoms, and various questionnaires are used. Neurological examinations are performed with regard to concomitant diseases of RBD. Thus, REM sleep behavior disorder can be verified in association with Parkinson’s disease or Lewy body dementia. In addition, RBD can be detected by polysomnography. This involves using an EMG to examine the activity of the mentalis muscle (chin muscle) during REM sleep.Increased activity of the muscle can be assumed to be RBD.

Complications

REM sleep behavior disorder primarily increases the risk for accidents and falls from bed. Because the affected person is briefly unable to distinguish between dreaming and waking after waking, there is a risk of danger to self and others. If the affected person suffers from a mental illness, the behavioral disorder can possibly cause traumatic states, delusional behavior and other complications. REM sleep behavior disorder also often occurs as an initial symptom of Parkinson’s disease or Lewy body dementia. As a result, further symptoms and sometimes an increase in behavioral disturbance occur. Treatment via clonazepam may cause side effects such as muscle weakness, dizziness, unsteadiness of gait, and fatigue. Rarely, headache, nausea, skin irritation and urinary incontinence occur. In isolated cases, allergic reactions or allergic shock occur. In children, the drug can trigger premature development of secondary sexual characteristics. Melatonin, which is often prescribed concomitantly, can lead to nightmares, hyperactivity and weight gain in addition to the typical side effects. Especially at the beginning of medication, irritability, restlessness, fatigue and dry mouth may also occur, although in the case of melatonin, these complaints disappear after a few days to weeks without further complications.

When should you see a doctor?

REM sleep behavior disorder should always be treated by a doctor. It usually does not result in self-healing, and the disorder usually cannot be treated by self-help means either. Therefore, treatment by a physician is essential. As a rule, REM sleep behavior disorder must be treated if the affected person dreams permanently of insects or of other animals that chase him/her during sleep. The patient usually has to fight off these animals to avoid dying in his sleep. Likewise, the condition can lead to sleepwalking, which should also be treated to prevent further complications and discomfort. In most cases, the symptoms of REM sleep behavior disorder are registered by outsiders, so that especially they should make the affected person aware of the disease. The condition can be treated by a psychologist in many cases. However, how long the treatment will take cannot be generally predicted.

Treatment and therapy

For the treatment of idiopathic REM sleep behavior disorder, the main drug currently used is clonanzepam. This drug belongs to the benzodiazepines and has a sedative and muscle relaxant effect. It is taken before bedtime to reduce muscle activity during REM sleep. Even with its long-term use, there is no loss of effect. Some patients also respond positively to melatonin. So far, however, there is unfortunately no prospect of a cure for RBD. The symptoms in the idiopathic form of the disease can be improved. Unfortunately, this has no effect on the development of Parkinson’s disease or Lewy body dementia. No adequate studies are yet available for the therapy of RBD as an accompanying symptom of neurodegenerative diseases. Increasing the dopaminergic dose improves the symptoms of Parkinson’s disease but does not change the frequency and intensity of an existing REM sleep behavior disorder.

Prevention

There are no known preventive measures against REM sleep behavior disorder. With a corresponding genetic predisposition, RBD may occur after the age of forty. At the same time, its occurrence can be interpreted as a sign of a predisposition to neurodegenerative diseases. It has not yet been clarified whether particular stress situations are possible triggers of the disease. According to a Swedish study, the incidence of Parkinson’s disease can be reduced by physical activity. The extent to which this also applies to REM sleep behavior disorder requires further investigation.

Follow-up

REM behavior disorder is a sleep disorder, a parasomia. REM means rapid eye movement. These movements often occur during falling asleep or waking up. NREM is light sleep and deep sleep and is manifested by a decrease in temperature, change in breathing, a decrease and increase in pulse rate, and lower blood pressure.Symptoms that occur with NREM are sleepwalking and anxiety disorders. When sufferers sleepwalk, they often do not remember it. It is also difficult for relatives to wake them up. Disturbing features of REM include lack of muscle activity, an irregular heartbeat, and nightmares. It is therefore a sleep behavior disorder. The dreams that occur often frighten the dreamer with their aggressive thoughts. The diagnosis is made in the sleep laboratory with the help of the medical history and questionnaires to ensure the clinical diagnosis. Video monitoring may also be performed. During follow-up, attention must be paid to whether any brain changes occur within a few years, as well as Parkinson’s disease. Sensory perception, attention and memory are tested. An ultrasound and CT scan will show the condition of the brain. How REM behavior disorder develops also depends on the patient’s cooperation.

Here’s what you can do yourself

If a patient is diagnosed with REM sleep behavior disorder, it is essential to clarify whether this disorder is a concomitant disease and/or heralds the onset of other diseases. Only then can appropriate therapies be initiated. REM sleep behavior disorder cannot be cured. It can only be improved with medication. As a supportive measure, the mostly male patients should learn relaxation techniques to perform before going to bed. Progressive muscle relaxation according to Jacobson is easy to learn. Alternatively, however, yoga, Qigong and Tai Chi are also suitable. Even music therapy or EFT tapping therapy could provide patients with relief. With REM sleep behavior disorder, the patient endangers himself and others. For one thing, the risk of accidents is greatly increased because the patient is acting out his or her dream content. In addition, there may be the effects of the medications he is receiving to treat other conditions, which can lead to gait unsteadiness or dizziness. Therefore, the bed should be secured as much as possible. Pointy objects, loose rugs and other tripping hazards should be removed from the bedroom. A bed guard would also be recommended to prevent the patient from accidentally falling out of bed. For patients with REM sleep behavior disorder, spouses are also at risk at night. If living arrangements permit, this partner should sleep in another room or at least in a different, remote bed.