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Narcolepsy is a chronic neurological disorder caused by the brains inability to regulate a stable sleep-wake cycle. People who suffer from narcolepsy have mixed signals sent from their brain about when to sleep, which is why narcoleptics fall asleep at inopportune times. One may develop narcolepsy at any time, although onset of the first symptom usually occurs after puberty, in late teens to young adulthood. Excessive daytime sleepiness is the first noticeable symptom of narcolepsy. It can take a number of years for this symptom to progress to a point of concern and for other related symptoms to present. Narcolepsy commonly goes undiagnosed or misdiagnosed because few people realize they are experiencing a neurological disorder when the symptoms begin. It is thought that as many as 125,000 to 200,000 Americans have narcolepsy, although fewer than 50,000 have been properly diagnosed.
Causes of Narcolepsy
The cause of narcolepsy is still unknown, however there is much research being done to find the cause of the disorder. Scientists and researchers believe there are multiple factors that influence the disorder. A recent discovery has shown that people who suffer from narcolepsy lack the chemical hypocretin. This chemical is responsible for the feeling of alertness and aids in sleep regulation. Researchers have also found abnormalities in some regions of the brain that regulate REM cycles in narcoleptics. The current position is that all of these factors contribute to narcolepsy.
Symptoms of Narcolepsy
People who suffer from narcolepsy can experience a number of symptoms, excessive daytime sleepiness being the most common. Many people who suffer from narcolepsy do not realize excessive daytime sleepiness is a symptom, because daytime sleepiness in their mind is not an indicator of disease. There are other symptoms associated with narcolepsy as well, such as cataplexy and sleep paralysis. Below is a brief description and explanation of the most prominent symptoms most commonly associated with narcolepsy.
Excessive Daytime Sleepiness
The first symptom to appear is excessive daytime sleepiness, often referred to as EDS. This primary symptom may persist for years before any other symptoms present. EDS is the most prevalent symptom, reported in 100% of narcoleptics. Unlike daytime sleepiness, excessive daytime sleepiness occurs whether or not a narcoleptic has gotten enough sleep. The urge to sleep is almost unbearable, almost an overwhelming urge to fall asleep at in appropriate times. This urge can come and go multiple times though out the day. People who have EDS often report feeling very fatigued or having low energy. Some related symptoms of EDS are mental cloudiness, lack of energy, depressed mood, extreme exhaustion and automatic behavior. Often when one suffers from EDS, they will also experiences “microsleeps”. These tiny instances of sleep are very brief and last for only a few seconds or minutes at a time. When people awake from a microsleep, they tend to report feeling very refreshed and will be alert for about an hour or two before sleepiness sets in again. During a microsleep, one may continue an activity as if they were awake; these occurrences are referred to as automatic behavior. For instance, if a person had been in a meeting taking notes, they may fall asleep and continue taking notes. However, since a person would truly be sleeping, their cognitive ability is impaired and their note taking would result in scrawling on a notepad.
What is Cataplexy?
Cataplexy is a sudden loss of muscle tone that causes feelings of weakness and loss of voluntary muscle control. Usually cataplexy is the second symptom to present after EDS. By itself, cataplexy could be wrongfully diagnosed as a seizure disorder. Cataplectic attacks vary in severity from slight momentary drooping of the eyelids, to quite severe with the inability to stand. Most commonly, persons with narcolepsy experience mild cataplectic attacks, where arm or leg muscles become weak, speech is slurred or their head droops. Even in the most severe attacks, sufferers remain fully conscious, entirely aware of what is occurring, and what is happening around them. These attacks can occur randomly, but most often are brought on by any strong emotions. Laughter is reported as the most common stimulus.
Sleep paralysis is literally the paralysis brought on by entering into REM sleep. This occurs naturally every night when a person is sleeping. When sleep paralysis occurs with narcolepsy, it can happen at any point during ones wakeful hours. Like cataplexy, the person having the episode will remain conscious during the attack. The paralysis lasts briefly, after which the affected muscles will return to normal. Sufferers will rapidly recover from these episodes. The paralysis will not result in any permanent damage, or long-term paralysis. Some who suffer from sleep paralysis report the feeling that they cannot breathe, even though they are able to the entire time.
Hallucinations during Sleep
There are two different types of hallucinations associated with narcolepsy. Hypnagogic hallucinations occur at the onset of sleep, while hypnopompic hallucinations occur while waking. These hallucinations during sleep can occur along with sleep paralysis or as one is falling asleep or waking up. Both of these hallucinations are a portion of the REM sleep cycle interfering with normal wakefulness. The hallucinations are very vivid and can incorporate what is occurring around the person who is hallucinating. People who have experienced these events report are very frightening and disturbing. Most often, the hallucinations are visual, but they can incorporate all of the senses.
Diagnosis of Narcolepsy and Cataplexy
The first step in diagnosing narcolepsy or cataplexy is discussing symptoms with your healthcare provider. Generally, narcolepsy and cataplexy are clinical diagnoses – the diagnosis is made by symptom presentation. Your health care professional may diagnose your condition based on symptoms alone or they may want you to have some testing done. For testing, you may be referred to a sleep specialist or to a sleep center. Most health care providers, whether they are a primary care provider, or a specialist may want a sleep study done to confirm their diagnosis.
If one is visiting their provider for an initial evaluation there are a few different diagnostic tools a health care provider may use to determine your diagnosis. The Stanford Narcolepsy Questionnaire, which is a rather extensive survey, will aide in diagnosing the severity of ones condition and help determine weather or not you have been experiencing cataplexy and to what degree. The provider may also ask you to fill out the Epworth Sleepiness scale, a brief quiz, designed to determine to what extent you suffer from daytime sleepiness and what the possible causes are. In addition, your provider may ask you to keep a sleep diary for a couple of weeks. This will work as a “log” of a persons’ typical sleep patterns for a health care provider and will assist him or her in proper diagnosis and treatment.
Generally, a health care provider will want to confirm the diagnosis of narcolepsy with a sleep study. The sleep study most commonly includes a polysomnogram (PSG) and a Multiple Sleep Latency Test (MSLT).
A PSG will electrically monitor your psychological state, heart rate, breathing and muscle activity throughout the night. A sleep specialist and your health care provider will analyze the records created to determine what the cause of ones symptoms are. A Multiple Sleep Latency Test (MSLT) will simply measure how long it takes you to fall asleep, or if you are apt to fall asleep when you would normally be awake. The MSLT is usually a videotaped record of a persons’ normal nights sleep.
Through both of these tests, a health care provider will be able to determine if there are any abnormalities during ones REM cycle. In addition, these tests will determine what a persons’ normal level of sleepiness is at night. The results from these tests may also provide a health care professional the opportunity to rule out any external causes of daytime sleepiness.
Treatment of Narcolepsy and Cataplexy
Currently there is no cure for narcolepsy, although research continues. Fortunately, there is treatment for the most disruptive symptoms. At this time, there is more than one treatment option available.
Recently there have been some new medications approved by the FDA for the control of symptoms associated with narcolepsy. Some of these medications work specifically to reduce cataplectic attacks, while others to reduce episodes of EDS. Some health care providers may determine that a combination of antidepressants and stimulants will suffice to manage ones symptoms. As with many medications, there are side effects. Be sure to speak with a health care professional about what the benefits of using a medication could be and about any possible side effects.
Ones health care provider may also suggest some behavioral therapies or lifestyle changes to combat symptoms. The first step may be to adhere to a sleep schedule and, if possible, avoid shift work. Having ones internal clock set on a regular sleep-wake cycle can aide in alleviating EDS. Your health care provider may also suggest naps of about 15-20 minutes in length scheduled through out the day. Avoidance of heavy meals or alcohol may also leave one feeling less sleepy at inopportune times.
In addition, there are several steps one can take to ensure a restful nights’ sleep; avoidance of caffeine and nicotine are suggested. Regular exercise, as long as it done well before bedtime, does promote restfulness. Make sure ones sleep environment is comfortable and is used only for rest or sex. Also, try to relax before bed by reading a book or taking a warm bath.