How Parasomnias Affect Sleep and Sleep Apnea

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How Parasomnias Affect Sleep and Sleep Apnea

By Admin

Parasomnias are a class of sleep disorders that involve disruptions or arousals during various stages of sleep or waking. While these types of disorders are extremely common, there is a considerable shortage of information on their causes, symptoms, and possible treatments, especially when more than one disorder is involved. While sleep apnea is classified as a sleep-related breathing disorder (SBD), it is closely related to parasomnias and often results in overlap with other disorders, either as symptoms or as comorbid relationships. More specifically, patients diagnosed with obstructive sleep apnea (OSA), the form of sleep apnea related to physical obstructions in the upper airway, are especially prone to other related disorders such as REM sleep behavior disorder, confusional arousals, and nightmares. This is an area of medicine in urgent need of further research, both in terms of large-scale objective studies to assess current understandings, and in regard to advancing treatment options across the board. The more we know about these highly prevalent disorders, the better we can treat their underlying causes and improve the quality of life for patients throughout the world.

Types of Parasomnias

The International Classification of Sleep Disorders-3 (ICSD-3) defines parasomnias as undesirable physical events or experiences occurring during sleep onset, during sleep, or during arousal from sleep. Subdivisions include three main groups: Non-rapid eye movement (NREM)-related parasomnias, rapid-eye movement (REM)-related parasomnias, and unspecified parasomnias. But most occur during arousals from REM sleep or partial arousals from NREM sleep. They can also be classified as primary parasomnias, which are sleep disorders, and secondary parasomnias, which are the results of other disorders, psychological conditions, or physical health problems that can affect the sleep cycle. NREM-related parasomnias include disorders of arousal such as sleepwalking, sleep terrors, confusional arousals, and sleep-related eating disorder. While some behaviors such as violence and/or sexual conduct during sleep are classified as NREM-related parasomnias, in some cases they may arise from other periods of sleep onset or waking. REM-related parasomnias include more disorders that occur during sleep such as nightmares, sleep paralysis, and REM-sleep behavior disorder (sleep movements), while other unspecified parasomnias include everything from sleep-related groaning or talking to exploding head syndrome (EHS), which is the perception of loud noises during sudden awakenings. Each of these disorders has its own diagnostic criteria and treatment options, though any one of these examples can be the result of other underlying conditions such as sleep apnea. While the relationship between sleep apnea and disorders like insomnia are well documented, resources on the link between sleep apnea and parasomnias are more scarce, emphasizing a need for more detailed research on these complex but increasingly common overlap conditions.

Most Common Parasomnia Disorders

While sleep-related disorders are diverse and numerous, some of the most common examples include sleep terrors, sleep walking and talking, confusional arousals, REMsleep-related behavior disorder, nightmares, and sleep paralysis.

Sleep terrors (also called night terrors)

Sleep terrors are fearful arousals from sleep that often involve crying out or gasping. Usually, the person wakes with an elevated heart rate, sweating, and/or rapid breathing. Often, the person will not remember the experience in the morning or later in the day. Night terrors occur during deep non-REM sleep, and can be dangerous to those close to them.

Sleepwalking (also called somnambulism)

Sleepwalking is another type of disorder of arousal and occurs in NREM sleep. A sleepwalker appears to be awake, but is not, and often retain no memory of their actions. On some occasions a sleepwalker may wake up in the middle of the experience and appear confused or return to bed and fall back to sleep. This disorder is very dangerous because a sleepwalker can potentially walk anywhere, including down steps or out into a street if not fully awake. While some suggest that waking a sleepwalker is dangerous, it is often more dangerous not to wake them, as the behavior can potentially hurt them or others.

Confusional arousals

Confusional arousals usually occur when a person is awakened from NREM sleep. As its name suggests, the person will wake in confusion and perhaps not understand where they are or what they are doing. These experiences can sometimes be prolonged with interaction, so caution is recommended for sleep partners. Confusional arousals are common among children as well, though they often continue into adulthood.

Nightmare disorder

Nightmares are frightening dreams, and when they persist over time, can be extremely unsettling. Unlike night terrors, nightmares occur most often during REM sleep, when people are doing the majority of their dreaming. Those who experience nightmares often have good recall of the dream, and are fully awake when aroused. It can be difficult to return to sleep following a bad nightmare, and sometimes the person will wake up completely and leave the bed for some other activity before attempting to sleep again. While occasional nightmares are normal, continued nightmares can cause anxiety and sleep deprivation, and should be assessed by a doctor if they persist.

REM sleep behavior disorder (RBD)

Rapid eye movement (REM) sleep behavior disorder involves movement during dream states. The dreamer may kick legs or move arms seemingly to act out a dream, and this can be dangerous to the dreamer as well as a bed partner. Often the result of dramatic or violent dreams, REM sleep behavior disorder is very common among senior citizens Normally, REM sleep involves a state of paralysis (atonia), but the condition somehow limits this state and allows the body to move. This condition can be caused by some medications, such as antidepressants (reuptake inhibitors), and in some cases treatment may include additional medications to counteract the side effects.

Sleep paralysis

Sleep paralysis is the opposite of REM sleep behavior disorder. During sleep paralysis, the body prolongs the atonia of REM sleep, rather than suspending it, causing a moment of paralysis during waking. While this is normally a brief period, lasting only a few seconds, it can be terrifying to the person experiencing it. Often, the experience is accompanied by hallucinations or feelings of panic. While the underlying cause of sleep paralysis is unknown, it does often occur during changes in a person’s sleep schedule, and unlike other sleep disorders, sleep paralysis can at times be interrupted by the sound or touch of another person.

Parasomnias and Sleep Apnea

According to research presented at the 23rd Annual Meeting of the Associated Professional Sleep Societies (APSS), the frequency of parasomnia symptoms in individuals with OSA was averaged at 9.5 percent, compared to 2.9 to 4 percent for those without OSA. Thirty-eight percent reported sleep paralysis, 29 percent reported sleep-related hallucinations, 20 percent reported REM sleep behavior disorder), and 9 percent reported sleepwalking. These findings are consistent with other sources reporting that nearly one in 10 patients with OSA have experienced regular parasomnia symptoms of the same type. Since apnea events are known to cause sleep fragmentation, it is likely that parasomnias can develop from these disruptions, which can be extremely frequent for untreated cases. The good news is that treatment, especially using continuous positive airway pressure (CPAP) therapy, can have an integrated effect on more than one condition at the same time. At least 20 percent of the APSS study’s participants reported an improvement of their parasomnia symptoms with the use of PAP therapy. According to the ICSD-3, OSA is a recognized precursor to common parasomnias such as sleepwalking and confusional arousals. Some have suggested that hypoxemia, caused by the apnea events, can trigger these behaviors, but further studies are needed to observe the specific mechanisms involved. While there is a strong theoretical foundation in regard to parasomnia symptoms and related medical conditions, further large-scale objective studies could increase our knowledge in these areas and help to treat the growing numbers of cases throughout the world.

Treatment Options

Parasomnias are common in the general population, but treatments vary depending on the severity of the symptoms and whether they persist over prolonged time periods. While some parasomnias may be an indication of more serious medical conditions, others may simply be occasional experiences triggered by stress, sleep schedule changes, or other factors in daily life. Good sleep hygiene, reduced stress, avoidance of substances that interfere with sleep, and use of proper medication when necessary should be enough to reduce the occurrences and severity of the symptoms in most cases. But when parasomnias persist despite these attempts at treatment, a referral to a sleep specialist is recommended. In particular, when parasomnia symptoms arise in addition to problems normally associated with sleep apnea, you should always consult a specialist. These conditions may be the result of the sleep apnea, or they could be a sign of other problems. Some parasomnias may be complex and prolonged, and evaluations are especially recommended for patients whose activities are potentially harmful, uncomfortable, or unsettling to others. It’s always good to practice good sleep hygiene and make a note of any changes to your sleep experiences, but if a sleep disorder symptom is persisting despite regular adherence to CPAP therapy, it is safest to see a doctor or specialist to assess the problem and discuss your options.