Sleep paralysis is a subjective feeling of being entirely conscious but unable to move, speak, and react to any external stimuli. This phenomenon happens between the stages of sleep and wakefulness. During the transition, the sleeper is unable to move or speak for a few seconds to a few minutes.
Patients will usually present with bouts of paralysis in periods before sleeping and before awakening. They are unable to move, speak and react in this transition which usually last for a few seconds to a few minutes. This paralysis spells conclude on their own or when the patient is touched or moved. The characteristic hypnogogic and hypnopompic hallucinations are often seen in sleep paralysis and are often revered as a terrifying experience in most patients.
The diagnosis of sleep paralysis is reached when all other sleep disorders that potentially give rise to paralysis have been ruled out. The most common medical condition investigated upon with sleep paralysis is narcolepsy which actually includes sleep paralysis as one of its major diagnostic criteria. The following sleep study tests and diagnostic modalities are implored in the investigation of sleep paralysis:
In the majority of patients suffering from sleep paralysis, treatment may not be required because it is clinically benign. For cases where the underlying causes are identified like the lack of sleep, some lifestyle modifications may be effected to increase the duration of sleep to avert the paralytic spells . Patients having a mental health condition suffering from sleep paralysis may benefit from pharmacotherapy, psychotherapy, and family support that greatly reduces the incidence of the disorder. In severe cases of sleep paralysis, tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRI) are commonly given to control the recurrence of the disorder .
Although the experience of sleep paralysis is adjudged to be most dreadful and terrifying to most subjects, there has been no scientific evidences linking it to serious medical events or disorders. Sleep paralysis has a good prognostic outlook for all cases.
Physiologically, muscles relax and becomes periodically paralyzed during normal sleep patterns. In some instances, these mechanisms of paralysis may temporarily persists during the transition of awakenings. Moreover, there are many events or risk factors that increase the likelihood for the development of sleep paralysis. Among these:
Among patients diagnosed with narcolepsy, 30 to 50% have experienced a form of isolated sleep paralysis . Sleep paralysis has a worldwide incidence of 6.2% of the population, with any of them experiencing a paralytic attack of at least once a month or once a year. Of these patients, only 3% suffers from recurrent isolated sleep paralysis (RISP) which is a type of sleep paralysis that occurs nightly . There is no sexual predilection in sleep paralysis. The adolescents and the young adult’s age group are more prone to sleep paralysis compared to any other age segments. The prevalence of sleep paralysis peaks at a mean age of 25 to 44 years old, representing 36% of all the cases recorded .
The researches done in sleep sciences have afforded several theories in the pathogenesis of sleep paralysis. The more common theories links sleep paralysis as a type of parasomnia or sleep walking which emanates from the dysfunctional overlap of the rapid eye movement (REM) stage of sleep and the waking stage of sleep . Some current polysomnographic studies have made observations that any disturbances done in the regular sleeping pattern can induce sleep paralysis among its respondents .
Another major theory postulates that sleep paralysis stems out as a result of the neural signaling imbalances between the cholinergic neural populations that facilitates wakefulness and the serotonergic neural populations that maintains normal sleep . The patterns of REM sleep fragmentations and the occurrence of hypnogogic and hypnopompic hallucinations among family lines have catered the idea that isolated sleep paralysis may involve genetic mechanisms in its pathogenesis .
Patients who are at risk of sleep paralysis may extend their sleeping hours to prevent its recurrence. One should avoid stimulants like alcohol, tobacco and recreational drugs that may alter one’s sleeping patterns. Patients are strongly advised to stay supine during sleep to reduce attacks of sleep paralysis and lessen the upper airway obstructions .
Sleep paralysis is a dreadful form of paralysis that clinically occurs upon waking up or just before going to sleep. Patients who undergone sleep paralysis complain of sensation of noise, olfaction, levitation and paralysis during the attacks. Sleep paralysis is not usually associated with a severe medical condition but the whole event will usually be frightening to the patient. Sleep paralysis occurs either before falling asleep which is also referred to as hypnogogic sleep paralysis or predormital sleep paralysis, or just before waking up otherwise known as hypnopompic or postdormital sleep paralysis.
Sleep paralysis is a dreadful and terrifying form of paralysis that periodically occurs upon waking up or just before going to sleep.
Sleep paralysis is commonly seen among the young adult population with high familial tendencies. Patients with variable sleeping patterns and those who have some form of sleep deprivation may also be prone to the disease.
The disorder occurs in the period just before sleeping or in the period just before awakening. Patients may be unable to move, speak, and react to any stimuli within a few seconds or minutes.
Patients may offer a detailed medical history of the event at home. Sleep studies that makes use of the polysomnographs and the home sleep test kits may elucidate the disorder.
Treatment and follow-up
In majority of cases of sleep paralysis, treatment may never be required. Lifestyle modifications may be done to correct abnormal sleeping patterns. Medications like tricyclic antidepressants and SSRI’s may be given for severe cases of sleep paralysis.