Narcolepsy: Symptoms, Diagnosis and Treatment Options
Disabled World: Revised/Updated: 2017/12/02
Synopsis: Information regarding narcolepsy a neurological sleep disorder affecting 3 million people worldwide.
Narcolepsy is a neurological condition most characterized by Excessive Daytime Sleepiness (EDS), in which a person experiences extreme tiredness, possibly culminating in falling asleep during the day at inappropriate times, such as at work or school.
Narcolepsy, also known as hypnolepsy, is a chronic neurological disorder that involves poor control of sleep-wake cycles. People who have narcolepsy often fall into REM sleep quickly and wake up directly from it. As a result, they may have vivid dreams while falling asleep and waking up. People with narcolepsy experience periods of extreme daytime sleepiness and sudden, irresistible bouts of sleep that can strike at any time. These sleep attacks usually last a few seconds to several minutes.
A narcoleptic will most probably experience disturbed nocturnal sleep, which is often confused with insomnia, and disorder of REM or rapid eye movement sleep. It is one of the dyssomnias. Dyssomnias are a broad classification of sleeping disorder that make it difficult to get to sleep, or to remain sleeping.
The main characteristic of narcolepsy is excessive daytime sleepiness (EDS), even after adequate night time sleep. A person with narcolepsy is likely to become drowsy or fall asleep, often at inappropriate times and places. Daytime naps may occur without warning and may be physically irresistible. These naps can occur several times a day. They are typically refreshing, but only for a few hours. Drowsiness may persist for prolonged periods of time. In addition, night time sleep may be fragmented with frequent awakenings. Other "classic" symptoms of narcolepsy, which may not occur in all patients, are;
- sleep paralysis
- automatic behavior
- hypnagogic hallucinations
Narcolepsy can occur in both men and women at any age, although its symptoms are usually first noticed in teenagers or young adults.
It is estimated that as many as 3 million people worldwide are affected by narcolepsy. In the United States, it is estimated that this condition afflicts as many as 200,000 Americans, but fewer than 50,000 are diagnosed. While the cause of narcolepsy has not yet been determined, scientists have discovered conditions that may increase an individual's risk of having the disorder. Specifically, there appears to be a strong link between narcoleptic individuals and certain genetic conditions.
Cognitive, educational, occupational, and psychosocial problems associated with the excessive daytime sleepiness of narcolepsy have been documented. For these to occur in the crucial teen years when education, development of self-image, and development of occupational choice are taking place is especially damaging. While cognitive impairment does occur, it may only be a reflection of the excessive daytime somnolence.
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. It is also possible for cataplexy to occur in isolation. Two tests that are commonly used in diagnosing narcolepsy are the polysomnogram and the multiple sleep latency test (MSLT). These tests are usually performed by a sleep specialist.
- 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 test, 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 (sleep onset latency). 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.
Narcolepsy has no cure, but medicines, lifestyle changes, and other therapies can improve symptoms. Narcolepsy treatment is tailored to the individual, based on symptoms and therapeutic response. The time required to achieve optimal control of symptoms may take several months or longer.
Medication adjustments are also frequently necessary, and complete control of symptoms is seldom possible. While oral medications are the mainstay of formal narcolepsy treatment, 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 such as methylphenidate, racemic amphetamine, dextroamphetamine, and methamphetamine, or modafinil, a new stimulant with a different pharmacologic mechanism.