Sleeping Disorders
Narcolepsy
Narcolepsy is a neurological condition most characterized by Excessive Daytime Sleepiness (EDS), episodes of sleep, and dysfunction of Rapid Eye Movement (REM) sleep. The EDS can be quite overwhelming, and people suffering from Narcolepsy may fall asleep (from a waking state straight to REM sleep – skipping the intervening stages of sleep) at any time spontaneously and unwillingly, even after having an adequate night of sleep. For Narcolepsy sufferers, the order and length of Non-REM (NREM) sleep and REM sleep periods are disturbed, with REM sleep occurring at sleep onset instead of after a period of NREM sleep. Also, some of the aspects of REM sleep, such as lack of muscular control, sleep paralysis, and vivid dreams, may occur at other times in people with Narcolepsy. In narcolepsy, the brain does not pass through the normal stages of dozing and deep sleep but goes directly into (and out of) Rapid Eye Movement (REM) sleep, and this has several consequences: · Nighttime sleep does not include much deep sleep, so the brain tries to "catch up" during the day, hence the Excessive Daytime Sleepiness (EDS). · Narcoleptics fall quickly into what appears to be very deep sleep. · They wake up suddenly and can be disoriented when they do. · They have very vivid dreams, which they often remember. Narcoleptics may dream even when they only fall asleep for a few seconds.
Symptoms
People suffering from Narcolepsy may fall asleep at any time spontaneously and unwillingly, even after having an adequate night of sleep. A person with Narcolepsy is likely to become drowsy or to fall asleep, often at times and places considered inappropriate by others. Daytime naps may occur with or without warning and may be irresistible and overwhelming. Such naps can occur several times a day. They are typically refreshing for people suffering from Narcolepsy, but only if they last for a couple hours or less per nap. Drowsiness in people suffering from Narcolepsy may persist for prolonged periods of time. The nighttime sleep of people suffering from Narcolepsy may be fragmented and disturbed by frequent awakenings. In addition to the main symptoms above, one or more of the following symptoms may also occur in people suffering from Narcolepsy, and they may begin alone or in combination months or even years after the onset of the daytime naps: · Cataplexy: sudden episodes of loss of muscle function, ranging from slight weakness (such as sagging facial muscles, limpness at the neck or knees, and/or the inability to speak clearly) to complete body collapse. Such episodes may be triggered by sudden emotional reactions such as laughter, anger, surprise, or fear, and may last from a few seconds to several minutes. Even though muscle function has been lost, person suffering from Cataplexy remains conscious throughout the episode. · Sleep Paralysis: is the temporary loss of the abilities to talk or move when waking up. Sleep Paralysis may last from a few seconds to several minutes, and is often frightening but not dangerous for the person suffering from Sleep Paralysis. · Hypnagogic Hallucinations: are vivid, often frightening, dream-like experiences that occur while dozing, falling asleep, and/or while awakening. These hallucinations can be auditory, tactile, and/or visual. · Automatic Behavior: occurs when a person continues to function during sleep episodes, for example talking, putting things away, etc, but awakens with absolutely no memory of performing such activities. It is estimated that up to 40 percent of people with Narcolepsy experience Automatic Behavior during sleep episodes. Please Note: Excessive Daytime Sleepiness (EDS), Sleep Paralysis, and Hypnagogic Hallucinations may also occur in people who do not have Narcolepsy, especially if they are suffering from an extreme lack of sleep. However, Cataplexy is generally considered to be unique to Narcolepsy sufferers. Only about one-quarter of people with Narcolepsy experience all four of these other symptoms. Excessive Daytime Sleepiness (EDS) generally persists throughout the remainder of the life of the Narcolepsy sufferer, but Sleep Paralysis and Hypnagogic Hallucinations may or may not.
Causes
While the main cause(s) of Narcolepsy have not yet been determined, researchers believe that Genetics is associated with an individual's risk of having or developing the disorder. · HLA Complex: there appears to be a strong link between Narcoleptic individuals and certain genetic conditions. For example, an area of Chromosome 6, known as the HLA complex, has been linked to Narcoleptic individuals. How this link operates isn't precisely clear at this time, but certain variations of the HLA complex are believed to increase the risk of an auto-immune response to protein producing neurons in the brain. The protein produced by the HLA complex is called hypocretin (or orexin), and is responsible for controlling appetite and sleep patterns. Individuals with Narcolepsy often have reduced numbers of these protein producing neurons in their brains. · Inheritance: there also appears to be an inherited basis for at least some forms of Narcolepsy, meaning that the disorder can and does run in families. · Linked or Related Medical Conditions: It is now known that Narcolepsy appears in association with Rapid Eye Movement Behavior Disorder (RBD) (see section 4.10 below). This link is hardly surprising, as both RBD and Narcolepsy involve dissociation of sleep states probably arising from a disruption to the sleep control mechanisms.
Diagnosis
The diagnosis of Narcolepsy is relatively easy when all the symptoms are present. However, if the sleep attacks are isolated or rare, and Cataplexy is mild or absent, then diagnosis can be a lot more difficult. The following tests are performed by a sleep specialist to diagnose Narcolepsy: · Polysomnogram, and, · Multiple Sleep Latency Test. People with Narcolepsy fall asleep rapidly, enter REM sleep quickly, and may awaken often during the night. These tests are designed to test for this behavior. A Polysomnogram is a device that continuously records the brain waves and a number of other nerve and muscle functions during nighttime sleep, the results of which can be used to detect and distinguish between a range of possible sleep disorders that could cause the Excessive Daytime Sleepiness (EDS). For the Multiple Sleep Latency Test, a person is given a chance to sleep every 2 hours during times that they are normally awake. Observations are made of the time taken to reach various stages of sleep, and these can determine the degree of daytime sleepiness and also detect how soon REM sleep begins.
Complications / Issues
The symptoms of Narcolepsy, especially the Excessive Daytime Sleepiness (EDS) and Cataplexy, can often become so severe that they cause serious disruptions in a person's social, personal, and professional lives and severely limit their activities and independence.
Treatment
Several treatments are available for the symptoms Narcolepsy. These treatments treat the symptoms, but not the underlying cause, which at this time is incurable. The treatment(s) selected for Narcolepsy depend on the severity of the symptoms, and it may take weeks or months for an optimal treatment regime to be worked out. Complete control of sleepiness and Cataplexy is rarely possible. Narcolepsy treatment is achieved by lifestyle changes and, if necessary, medications. The main treatment of Excessive Daytime Sleepiness (EDS) in Narcolepsy is with a group of drugs called central nervous system stimulants. In addition to drug therapy, an important part of treatment is scheduling short naps (10 to 15 minutes) two to three times per day to help control Excessive Daytime Sleepiness (EDS) and help the person stay as alert as possible. These daytime naps are not a replacement for proper nighttime sleep. Where treatment for Excessive Daytime Sleepiness (EDS) is required, then the drowsiness may be treated with one of the following stimulants: · methylphenidate (Ritalin), · amphetamines (Adderall), · dextroamphetamine (Dexedrine), · methamphetamine (Desoxyn), · modafinil (Provigil), · codeine, or, · selegiline. For Cataplexy, antidepressant medications and other drugs that suppress REM sleep are prescribed, such as clomipramine, imipramine, or protriptyline, but this is only usually required in severe cases. A new medication, called gamma-hydroxybutyrate (GHB) (Xyrem), may be an effective for Narcolepsy because it increases the quality of nocturnal sleep. Caffeine and over-the-counter drugs are not effective for Narcolepsy treatment, and are not recommended.
Prevention
At this time, there is no prevention or cure for Narcolepsy. The best way to prevent the onset of the symptoms of Narcolepsy is for the sufferer to work with their doctor to discover the cause for their disorder, so that the causes can be treated, removed, or reduced. Ongoing communication between the doctor, the Narcolepsy sufferer, and their family members about the response to treatment is necessary to achieve and maintain the best control.
Night Terror
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