Sleep DisordersInsomnia, Circadian Rhythm Disorder, Restless Legs Syndrome, Narcolepsy, and Problem Sleepiness
Narcolepsy is a chronic sleep disorder with no known cause. The main characteristic of narcolepsy is excessive and overwhelming daytime sleepiness, even after adequate nighttime sleep. A person with narcolepsy is likely to become drowsy or to fall asleep, often at inappropriate times and places. Daytime sleep attacks may occur with or without warning and may be irresistible. These attacks can occur repeatedly in a single day. Drowsiness may persist for prolonged periods of time. In addition, nighttime sleep may be fragmented with frequent awakenings. Three classic symptoms of narcolepsy, which may not occur in all patients, are:
- Cataplexy: sudden episodes of loss of muscle function, ranging from slight weakness (such as limpness at the neck or knees, sagging facial muscles, or inability to speak clearly to complete body collapse. Attacks may be triggered by sudden emotional reactions such as laughter, anger, or fear and may last from a few seconds to several minutes. The person remains conscious throughout the episode
- Sleep paralysis: temporary inability to talk or move when falling asleep or waking up. It may last a few seconds to minutes.
- Hypnagogic hallucinations: vivid, often frightening, dream-like experiences that occur while dozing or falling asleep.
* Please note that daytime sleepiness; sleep paralysis, and hypnagogic hallucinations can also occur in people who do not have narcolepsy. In most cases, the first symptom of narcolepsy to appear is excessive and overwhelming daytime sleepiness. The other symptoms may begin alone or in combination months or years after the onset of the daytime sleep attacks. There are wide variations in the development, severity, and order of appearance of cataplexy, sleep paralysis, and hypnagogic hallucinations in individuals. Only about 20 to 25 percent of people with narcolepsy experience all four symptoms. The excessive daytime sleepiness generally persists throughout life, but sleep paralysis and hypnagogic hallucinations may not.
When Should You Suspect Narcolepsy?
The symptoms of narcolepsy, especially the excessive daytime sleepiness and cataplexy, often become severe enough to cause serious disruptions in a person’s social, personal, and professional lives, while severely limiting ones activities. You should be checked for narcolepsy if:
- You often feel excessively and overwhelmingly sleepy during the day, even after having had a full night’s sleep;
- You fall asleep when you do not intend to, such as while having dinner, talking, driving, or working;
- You collapse suddenly or your neck muscles feel too weak to hold up your head when you laugh or become angry, surprised, or shocked;
- You find yourself briefly unable to talk or move while falling asleep or waking up.
How Common Is Narcolepsy?
Although it is estimated that narcolepsy afflicts as many as 200,000 Americans, fewer than 50,000 are diagnosed. It is as widespread as Parkinson’s disease or multiple sclerosis and more prevalent than cystic fibrosis, but it is less well known. Narcolepsy is often mistaken for depression, epilepsy, or the side effects of medications.
Who Gets Narcolepsy?
Narcolepsy can occur in both men and women at any age, although its symptoms are usually first noticed in teenagers or young adults. There is strong evidence that narcolepsy may run in families; 8 to 12 percent of people with narcolepsy have a close relative with the disease.
What Happens In Narcolepsy?
Normally, when an individual is awake, brain waves show a regular rhythm. When a person first falls asleep, the brain waves become slower and less regular. This sleep state is called non-rapid eye movement (NREM) sleep. After about an hour and a half of NREM sleep, the brain waves begin to show a more active pattern again, even though the person is in deep sleep. This sleep state, called rapid eye movement (REM) sleep, is when dreaming occurs. In narcolepsy, the order and length of NREM and REM sleep periods are disturbed, with REM sleep occurring at sleep onset instead of after a period of NREM sleep. Thus, narcolepsy is a disorder in which REM sleep appears at an abnormal time. Also, some of the aspects of REM sleep that normally occur only during sleep–lack of muscle tone, sleep paralysis, and vivid dreams–occur at other times in people with narcolepsy. For example, the lack of muscle tone can occur during wakefulness in a cataplexy episode. Sleep paralysis and vivid dreams can occur while falling asleep or waking up.
How Is Narcolepsy Diagnosed?
Diagnosis is relatively easy when all the symptoms of narcolepsy are present, but if the sleep attacks are isolated and cataplexy is mild or absent, diagnosis is more difficult. Two tests that are commonly used in diagnosing narcolepsy are the polysomnogram and the multiple sleep latency test and a qualified sleep specialist usually performs both of these tests. The polysomnogram involves continuous recording of sleep brain waves and a number of nerve and muscle functions during nighttime sleep. When tested, people with narcolepsy fall asleep rapidly, enter REM sleep early, and may awaken often during the night. The polysomnogram also helps to detect other possible sleep disorders that could cause daytime sleepiness. For the multiple sleep latency tests, a person is given a chance to sleep every 2 hours during normal wake times. Observations are made of the time taken to reach various stages of sleep. This test measures the degree of daytime sleepiness and also detects how soon REM sleep begins. Again, people with narcolepsy fall asleep rapidly and enter REM sleep early.
How Is Narcolepsy Treated?
Although there is no cure for narcolepsy, treatment options are available to help reduce the various symptoms. Treatment is individualized depending on the severity of the symptoms, and it may take weeks or months for an optimal regiment to be worked out. Complete control of sleepiness and cataplexy is rarely possible. Treatment is primarily by medications, but lifestyle changes are also important. The main treatment of excessive daytime sleepiness in narcolepsy is with a group of drugs called central nervous system stimulants. For cataplexy and other REM-sleep symptoms, antidepressant medications and other drugs that suppress REM sleep are prescribed. Caffeine and over-the-counter drugs have not been shown to be effective and are not recommended. 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 and help the person stay as alert as possible. It is important to note that daytime naps are not a replacement for nighttime sleep. Ongoing communication among the physician, the person with narcolepsy, and family members about the response to treatment is necessary to achieve and maintain the best control. Individuals with narcolepsy, their families, friends, and potential employers should know that:
- Narcolepsy is a life-long condition that requires continuous medication.
- Although there is not a cure for narcolepsy at present, several medications can help reduce its symptoms.
- People with narcolepsy can lead productive lives if they are provided with proper medical care.
- If possible, individuals with narcolepsy should avoid jobs that require driving long distances or handling hazardous equipment or that require alertness for lengthy periods.
- Parents, teachers, spouses, and employers should be aware of the symptoms of narcolepsy. This will help them avoid the mistake of confusing the person’s behavior with laziness, hostility, rejection, or lack of interest and motivation. It will also help them provide essential support and cooperation.
- Employers can promote better working opportunities for individuals with narcolepsy by permitting special work schedules and nap breaks.
Where To Get More Information
Talk to your doctor if you feel excessively sleepy during the day, or if you fall asleep when you do not intend to. Together you can identify possible reasons for your sleeping difficulty and then try appropriate measure to correct the problem. Obtain a referral to UBC Sleep Disorders Clinic. Check out these useful websites:
Books related to Narcolepsy:
- Hla in Narcolepsy , Y. Honda, T. Juji (Editor)
- Narcolepsy , C. Guilleminault (Editor)
- Narcolepsy: A Funny Disorder That’s No Laughing Matter , Marguerite J. Utley
- Narcolepsy and Hypersomnia, Bedrich Roth
- Psychosocial Aspects of Narcolepsy, Meeta Goswami (Editor), et al Sleep Disorders: Insomnia and Narcolepsy , Henry Kellerman