Mental HealthWhat Is Narcolepsy? What Causes Narcolepsy?
Narcolepsy - from the French narcolepsie, which was derived from the Greek narke meaning numbness and lepsis meaning attack or seizure - is a chronic sleep disorder where the brain is unable to regulate the body"s sleep-wake cycles. People with narcolepsy may feel an overwhelming urge to sleep at various points in the day, and they will often fall asleep spontaneously for a few seconds to a few minutes. In extreme cases, narcoleptics (people with narcolepsy) will remain asleep for over an hour.
A study warned that people with narcolepsy who smoke are at a higher risk of burning.
The majority of patients with narcolepsy/cataplexy experience a number of symptoms of eating disorders, with an irresistible craving for food and binge eating as the most prominent features, a study found.
Who gets narcolepsy?
Narcolepsy appears to occur more often in men than women. There is wide country variation in narcolepsy diagnoses, ranging from one in 600 people in Japan to one in 500,000 people in Israel. The rate for the United States is about one in 2,000 people. Some people with narcolepsy have a relative who also has the condition, suggesting a possible genetic link.
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A Harvard study found that police officers are much more susceptible to sleep disorders, including narcolepsy, compared to other people.
What causes narcolepsy?
Currently, we do not know the exact causes of narcolepsy. Researchers have suggested that there may be a genetic role in the condition or something such as an infection that triggers the condition. There is also some evidence that a brain chemical called hypocretin plays a role in narcolepsy. Hypocretin helps regulate staying awake and keeps rapid eye movement (REM) sleep stable and occurring at the correct times. In people with narcolepsy, hypocretin levels are found to be very low. However, we do not know what causes damage to hypocretin cells - perhaps an infection or abnormal immune system response.
A Stanford researcher believes that narcolepsy is an autoimmune disorder after showing for the first time that a specific immune cell is involved in the disorder.
Another study explained that narcolepsy may be caused by environmental exposures before the age of onset in genetically susceptible individuals.
Scientists at the Universite de Montreal, Canada, revealed a high frequency of REM sleep without atonia among people with narcolepsy.
In another study a link was found between Parkinson"s disease and narcolepsy.
What are the symptoms of narcolepsy?
The main symptoms of narcolepsy include:
*Excessive daytime sleepiness (EDS) - overwhelming drowsiness and an uncontrollable need to sleep during the day
*Cataplexy - the sudden loss of involuntary muscle tone that may be triggered by sudden emotional reactions such as laughter, anger, surprise, or fear. A study found that people with narcolepsy with cataplexy have low levels of cerebrospinal fluid (CSF) hypocretin-1.
*Vivid hallucinations upon sleep onset or awakening
*Short episodes of total paralysis at the beginning or end of sleep
Additional symptoms include restless nighttime sleep and automatic behavior. Automatic behavior is when someone continues to function (talking, putting things away, etc.) during episodes of sleep but has no memory of performing the actions upon awakening.
How is narcolepsy diagnosed?
Although diagnosing narcolepsy is not difficult when all symptoms are present, the condition often remains undiagnosed for 10 to 15 years after the first symptoms appear. If narcolepsy is suspected, a physician will direct you to a sleep specialist for a more thorough examination. Doctors will be interested in a detailed sleep history, which will probably require filling out the Epworth Sleepiness Scale that gauges your level of sleepiness. In addition, you may be asked to wear a device that resembles a wrist watch called an actigraph. An actigraph measures how and when you sleep.
More complicated tests for narcolepsy require monitoring at a sleep center. For example, a polysomnogram consists of electrodes placed on your scalp before you fall asleep. This overnight test measures a variety of electrical signals from your brain, heart, muscles, and eyes while you sleep. In addition, a multiple sleep latency test will measure how long it takes to fall asleep four or five times during the day. Narcoleptics are able to fall asleep easily and enter REM sleep very quickly.
How is narcolepsy treated?
Although there is no cure for narcolepsy, there have been drugs approved that treat excessive daytime sleepiness (EDS) and cataplexy. For example, modafinil may be prescribed to combat EDS, and antidepressants such as tricyclics and selective serotonin reuptake inhibitors (SSRIs) may help control cataplexy. A drug known as GHB (Xyrem) is also used to treat cataplexy, but it is tightly controlled due to safety concerns. Preliminary research in healthy men suggests that the narcolepsy drug modafinil, increasingly being used to enhance cognitive abilities, affects the activity of dopamine in the brain in a way that may create the potential for abuse and dependence.
Behavioral modifications should also be employed when treating narcolepsy. This includes:
*Taking short, regularly scheduled naps when feeling sleepiest
*Improving the quality of nighttime sleep
*Maintaining a regular sleep schedule
*Avoiding alcohol and caffeine before bedtime
Written by Peter Crosta
Copyright: Medical News Today
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