What is Parasomnias?
Throughout history, the mystery and experience of sleep has fascinated people, as shown in various cultural references, including a quote from the ancient poem “Aeneid” by Virgil, which compared sleep to a peaceful death. In mythology, sleep was even represented as a divine character called Hypnos in ancient Greece, and as Somnos in Roman mythology. Despite our longstanding interest, the exact reasons why sleep is the way it is, remains a subject of curiosity and wonder.
It’s common for people to experience sleep problems. Indeed, nearly half of the main reasons why people see their doctors relate to issues with sleep patterns. When we sleep, our brain and body go through different stages known as the sleep cycle. These stages include Rapid Eye Movement (REM), where we dream, and non-REM (NREM), where we rest quietly. NREM is broken down further into stages from 0 to 3. These stages of REM and NREM cycle every 120 minutes, with the first REM stage, lasting 5-10 minutes, happening more frequently and for longer periods as the night progresses.
Now, when this sleep cycle is disrupted, either during sleep or while waking up, we refer to these incidents as ‘parasomnias’. This term was first introduced in 1932 by Henri Roger and derives from the Greek word “para” meaning ‘alongside’, and the Latin word “Somnus” meaning ‘sleep’. Parasomnias are defined as unusual behaviors, experiences, or physical events that occur in conjunction with sleep. Common types of these abnormal sleep behaviors include ‘REM sleep behavior disorder,’ ‘NREM sleep arousal disorders,’ and ‘nightmare disorder’.
What Causes Parasomnias?
The exact cause of sleep disorders known as parasomnias is still unknown, but many theories have been suggested. Some researchers think that disturbances of a deep sleep stage called NREM (Non-Rapid Eye Movement) may increase a person’s risk.
Several factors were found to disrupt this deep sleep stage, which include things your genes that you inherit from your parents, restless leg syndrome (a condition where you feel an uncomfortable sensation and have an irresistible urge to move your legs), not getting enough sleep, periodic limb movements (a condition where a person moves their limbs involuntarily during sleep), loud noises, sleep-related breathing disorders (problems with breathing while sleeping), being touched, alcohol, stress, medications, and fever.
Although further research is required, some experts think that there might be a connection between REM (Rapid Eye Movement) sleep disorders and neurodegenerative diseases (which leads to loss of function or death of nerve cells), conditions where the brain has less dopamine activity (a chemical in the brain that influences movement and mood), along with posttraumatic stress disorder (a mental health condition caused by a traumatic event), and narcolepsy (a disorder that affects control of sleep and wakefulness).
Risk Factors and Frequency for Parasomnias
NREM sleep disorders, including sleepwalking, are more common in younger people, while REM sleep disturbances often occur later in life. Sleepwalking is particularly common in children, with 15% experiencing at least one sleepwalking episode. However, most kids will stop sleepwalking by the time they become teenagers, this reduces the occurrence of sleepwalking to about 2 to 4%. Interesting to note is that children of parents who sleepwalk are more likely to sleepwalk themselves. In fact, if both parents used to walk in their sleep, over 60% of their kids would possibly do the same.
On the other hand, sleep terrors are less common amongst kids, affecting only about 3% of them. Nightmare disorder, which can bother up to 6% of people, and REM sleep behavior disorder, quite uncommon with only 1% of people experiencing it, are other sleep disturbances. It’s worth noting that having a REM sleep disorder could suggest a higher likelihood of having some other conditions like Parkinson’s disease, dementia with Lewy bodies, or multiple system atrophy. Half of the people with a REM sleep disorder could possibly have one of these conditions.
Signs and Symptoms of Parasomnias
Non-rapid eye movement (NREM) sleep arousal disorders are conditions that involve sleepwalking and night terrors. These behaviors exist in a sort of middle ground between being awake and in NREM sleep. Individuals who sleepwalk can get up and walk around without being aware of what they’re doing. This typically happens within the first three hours of sleep. If you wake them up, they might be disoriented, but they usually forget what happened. The episodes are normally brief, but they can cause concerns as sleepwalkers might unwittingly put themselves in dangerous situations, like opening windows or doors.
Night terrors occur in the early part of the sleep cycle too. They create intense moments of fear and agitation that can result in wild movements and screaming. After a night-terror episode, individuals typically experience anxiety, confusion, and disorientation, coupled with memory loss concerning the event.
Nightmare disorder, on the other hand, is characterized by recurrent, upsetting, and vivid dreams that usually revolve around threats to one’s safety and well-being. Unlike NREM sleep disorders, nightmares happen during the later part of the sleep cycle and people can typically remember their nightmares upon waking.
Another condition, rapid eye movement (REM) sleep behavior disorder, involves physically acting out dreams during REM sleep, a stage of sleep usually marked by complete muscle relaxation and vivid dreams. This condition causes people to display a variety of unusual actions, like talking or moving during sleep. Because REM sleep happens most frequently in the latter part of the night, these behaviors tend to happen then too. These actions may disturb the person or a bed partner, and might even lead to the person getting injured. Individuals with REM sleep behavior disorder usually remember their dreams when they wake up.
Testing for Parasomnias
If you’re having problems with your sleep, your doctor will likely ask for a detailed history of your sleep patterns, as well as your medical and mental health history. They may ask about the current medications you’re taking, including both prescription and recreational drugs, as some drugs are known to cause or worsen certain sleep disorders. These can include types of antidepressants, blood pressure medications, and sleep aids.
Your doctor might ask you to keep a sleep log, which tracks your sleep patterns. If you have a partner who shares your bed, they may be asked to provide information about any unusual movements, snoring, or breathing difficulties you may have while sleeping. A specialized sleep study, known as polysomnography, is often used to diagnose sleep disorders. This test uses a combination of brain wave monitoring (electroencephalography or EEG), muscle activity recording (electromyography or EMG), and eye movement analysis (electrooculographic or EOG) during sleep. This test helps to objectively evaluate and understand your sleep patterns and potential sleep-related problems.
There are various types of sleep disorders. Some happen during non-rapid eye movement (NREM) sleep, like sleepwalking and night terrors, usually occur during the first part of your sleep cycle. People usually don’t remember these events because they involve very little to no dream recall. Another type of sleep disorder is nightmare disorder, which involves intensely distressing dreams that are easily remembered and often involve perceived threats.
There are also sleep disorders that happen during rapid eye movement (REM) sleep. One of these is REM sleep behavior disorder, where people physically act out their dreams, which can be unsafe for them or their bed partner. These episodes tend to occur more than 90 minutes after falling asleep and the person is fully awake, alert, and oriented when they wake up from an episode. Polysomnography can often identify these REM sleep disorders due to the specific patterns of brain and muscle activity they cause during sleep.
Treatment Options for Parasomnias
Most abnormal sleep behaviours, known as parasomnias, can be effectively treated using a type of medication called benzodiazepines (BZDs). Researchers believe that these drugs help by suppressing certain stages of deep sleep and rapid eye movement (REM) sleep, which are usually when these kinds of activities occur.
However, because benzodiazepines can have unwanted side effects and can potentially lead to addiction, doctors often recommend alternative treatments. These could include different kinds of antidepressants, sleep hormone melatonin, and drugs that increase serotonin levels (also called selective serotonin reuptake inhibitors or SSRIs). There’re also drugs known as alpha-1 antagonists, with prazosin as an example, that have been found to be particularly effective in treating nightmarish sleep.
Non-drug treatment options could involve talking therapies, awakening the patient on a regular schedule, hypnosis, and relaxation exercises.
For individuals who often have nightmares, a therapeutic approach called ‘imagery rehearsal’ could be beneficial. In this method, the person identifies a frequent nightmare and changes its narrative into a more pleasant one. The patient then practices this new narrative, which inadvertently alters the imagery in their subsequent dreams.
What else can Parasomnias be?
Doctors need to understand if a patient has any other health problems when dealing with sleep disorders, known as parasomnias. Often, sleep issues can be a sign of these health problems. For example, if an adult starts sleepwalking for the first time, it could be due to nighttime seizures, breathing problems while asleep, or because of their medication.
Sometimes, different types of sleep disorders can show similar characteristics, which can make it hard for the doctor to identify the exact problem. However, there are certain signs that can help. For example, usually, a patient’s eyes stay open during NREM sleep disorders, but stay closed during REM sleep disorders. Additionally, sleep terrors are often related to conditions like anxiety, depression, obsessive-compulsive disorder, and phobias. On the other hand, nightmares are often seen in patients with delirium, fever, those undergoing drug or alcohol withdrawal, or suffering from a long-term illness.
What to expect with Parasomnias
Luckily, most sleep disorders, also known as parasomnias, typically go away by the teenage years or occur as standalone circumstances. If these sleep disorders are symptoms of other, underlying health conditions, they will start to lessen as the main condition is treated. It’s important to note that when a patient stops taking certain medications like benzodiazepines, they may experience a return of symptoms, especially during stressful periods.
Possible Complications When Diagnosed with Parasomnias
People might face issues if they or their sleeping partners get hurt during an episode of parasomnia, a sleep disorder.
Preventing Parasomnias
Maintaining good sleep habits might be the most effective way to prevent certain sleep behavior disorders linked to different stages of sleep, known as Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM). Additionally, taking safety precautions at home, like putting alarms on doors, staying on the ground floor while sleeping, and securing windows with latches, can help patients sleep peacefully knowing they are protected from possible harm.
It’s also important for the person sharing the bed with the patient to be aware about potential violent sleep behaviors. This knowledge can help them avoid unexpected harm.
