What is Narcolepsy?
Narcolepsy is a sleep disorder in which the person has little control over the normal sleep-wake cycle. Those who suffer from this disorder are often extremely tired at work and at home; they often fall asleep without any prior warning. Narcolepsy patients can fall asleep even while standing up, leading to a risk of injury during a fall.
Some patients with narcolepsy can also suffer from a condition known as “cataplexy” in which they lose all muscle tone in their voluntary muscles, going limp or falling without warning. These come on as sleep attacks that can last only a few seconds or up to several minutes. They are also more prone to very vivid dreams or hallucinations or can suffer complete paralysis of their muscles before sleep or after awakening from sleep. Narcolepsy sufferers sleep poorly at night and actually don’t get any more real sleep than the average person.
Normal people who sleep will have periods of REM sleep and non-REM sleep. REM sleep is often associated with dreaming although a person can have a dream in non-REM sleep as well. People with narcolepsy often fall into REM sleep shortly after going to sleep, while normal people don’t fall into REM sleep until they have been sleeping for an average of 80-100 minutes. This difference is a hallmark of sleep in narcoleptic patients although no one knows the significance of having this happen.
Narcolepsy Risk Factors
Narcolepsy can happen in anyone across the world and it affects both males and females to an equal degree. Once a person develops narcolepsy, there is no cure and they must suffer from the disorder for the rest of their lives. Narcolepsy is an uncommon sleep disorder, affecting about one in 3,000 people. Researchers feel, however, that narcolepsy is underdiagnosed unless the patient also suffers from cataplexy. Narcolepsy can develop in children and adults, usually in people between the ages of 7-25.
There are a variety of sleep problems in patients who have narcolepsy. The most common Narcolepsy symptoms are as follows:
Excessive Daytime Sleepiness (EDS)
Excessive daytime sleepiness is the most common symptom of narcolepsy although it can occur in people who have other sleep disorders like insomnia and sleep apnea. About three-fourths of all narcolepsy patients report having EDS. It affects all aspects of daily living, making it a very disabling symptom to have. Because of the sleepiness, the patient has trouble concentrating and learning new things. They appear to be tired even when they have had adequate sleep. Such patients are prone to depression, exhaustion, and a lack of vital energy. After an attack of sleep, the person with narcolepsy often reports feeling temporarily refreshed and wakeful but this does not last more than a couple of hours.
Cataplexy is when the patient with narcolepsy loses all voluntary muscle control and falls to the floor or drops their head to the table. It can be confused with having a seizure; however, seizure patients usually have stiff or jerking muscles and not completely relaxed muscles as is seen in cataplexy. Cataplexy can involve all the muscles or just a few muscles. The loss of tone can be slight, such as having droopy eyelids, or can be major, such as being completely physically collapsed. During these attacks, the individual is usually completely aware of their surroundings and do not lose consciousness like patients who are having a seizure. Cataplexy can be triggered by strong emotions, both negative and positive emotions. Some people have an attack during episodes of stress or fear, while others can precipitate an attack by having extreme anger or even by laughing. Laughter is, in fact, the most common form of trigger for cataplexy. An attack of cataplexy seems to mimic the loss of muscle control seen in patients who are dreaming in REM sleep, except the person is awake during the attack.
People with narcolepsy can suffer from hallucinations when falling asleep or awakening from sleep. These can be frightening situations with very vivid, real-appearing hallucinations. Most of the hallucinations are visual although any of the other senses can be activated as well.
The person with narcolepsy can suffer an inability to speak or move while in the process of falling asleep. This is also like being in REM sleep except the patient is not yet fully asleep. The mechanism of action of this sleep paralysis is similar to being in REM sleep. The attacks of sleep paralysis can last a few seconds or a few minutes. After the attack is over, the person reverts to normal functioning.
People with narcolepsy have no trouble falling asleep but they instead have difficulty in staying asleep. Dreams may be vivid and the person may act out their dreams. Talking in one’s sleep is a common phenomenon in narcolepsy patients as are periodic leg movements during sleep.
What causes narcolepsy?
There may be many different causes of narcolepsy, including having low levels of hypocretin, which is a brain neurotransmitter that aids in keeping people awake. It may be hereditary in some cases and not hereditary in others. Around ten percent of narcoleptics will report having a relative who also has the condition. There is a hereditary condition in which there is a defect in the genes that go on to make hypocretin. This is, however, very rare and does not make up the largest population of those who have narcolepsy. Some people have an autoimmune condition causing their cataplexy. Their body is mistakenly attacking the cells of the brain that make hypocretin. Others develop cataplexy and narcolepsy after suffering some kind of brain trauma or a brain tumor affecting the parts of the brain responsible for REM sleep functioning.
While there is no cure for narcolepsy, medical treatments can help to manage it. Medications are available that can help control the symptoms. At the same time, the individual with the disorder can undergo lifestyle alterations that can reduce their symptomatology. Lifestyle changes associated with narcolepsy that can help somewhat include avoiding caffeine and alcohol before bedtime, developing a regular pattern of going to bed and waking up, smoking cessation, and avoiding the consumption of a large meal just before bedtime.
Two approved medications for the treatment of narcolepsy are modafinil and sodium oxybate. These are medications that keep the nervous system alert and wakeful. Other medications sometimes used for narcolepsy are amphetamines such as methylphenidate. Using these types of stimulants can result in many different side effects, including tolerance to the amphetamine so that more medication must be taken in order to have the same effect on the body’s ability to stay awake during the day. Amphetamines are also highly addictive and there is always the chance that the person will abuse the drug.
Other people with narcolepsy are treated with tricyclic antidepressants or SSRIs like Prozac. These drugs raise serotonin levels and seem to help improve daytime wakefulness. People with narcolepsy can also be treated with GHB, which is also called Xyrem®. This is a powerful sedative that improves sleep at night so that the wakeful hours are less sleepy and there are fewer attacks of cataplexy.
All of these things can improve nighttime sleeping, making way for a better time staying awake during the day.