Most of us go through our daily lives within one of two states of consciousness: sleep and wakefulness, with little overlap between the two. We may periodically become tired or rundown during the day, and need a little nap to refresh us. We may even doze off occasionally during a boring lecture or a dull movie. But for the most part, when we're awake, we're awake, and when we're asleep, we're asleep.
Now try to imagine what it would be like to live with a condition in which you rarely ever felt fully awake and hardly ever felt fully asleep; existing in a perpetual state where your life always feels caught in between the two, and without a moments notice may suddenly slip from one to the other. For sufferers of the sleep disorder narcolepsy, this is daily life.
What Is Narcolepsy?
Narcolepsy is a neurological disorder characterized by the brain's inability to control sleep/wakefulness cycles. People with narcolepsy suffer from chronic daytime sleepiness and episodes in which they fall asleep unexpectedly during the day. These "sleep attacks" can occur at any time, during any activity. Sleep attacks are not limited to periods of dull or low engagement activities but can happen during school or work hours, in the middle of a conversation, while eating, while exercising or playing sports, or most dangerously–while driving.
Narcolepsy affects approximately 1 in 2,000 people making it one of the most common sleep disorders.
For most people, sleep occurs in various stages. We enter sleep lightly and gradually progress into a deeper sleep. These early stages of sleep are called non-rapid eye movement (NREM) sleep. After approximately 90 minutes we enter rapid eye movement (REM) sleep where dreaming occurs. Throughout the course of a night, we experience 5 cycles alternating between NREM and REM sleep with about 75% of sleep spent in NREM.
However, for people with narcolepsy, REM sleep begins almost immediately in their sleep cycles and fragments of REM occur involuntarily during waking hours.
A common misperception about narcolepsy is that they sleep much more than the average person. In truth, people with narcolepsy sleep approximately the same amount as ordinary people, but they are unable to regulate the timing of their sleep.
Symptoms of Narcolepsy
Excessive Daytime Sleepiness (EDS). EDS is the most common symptom of narcolepsy and usually the first symptom to appear (usually between the ages of 10-20 years old). EDS is characterized by a chronic persistence of feeling sleepy and involuntary episodes of falling asleep without warning. Sleep attack bouts can last anywhere from several seconds to several minutes. People with EDS report it as feelings of mental cloudiness, a lack of energy and concentration, a depressed mood, or extreme exhaustion. EDS occurs even if the patient appears to have gotten plenty of sleep the night before, and usually persists throughout the day.
Sleep Paralysis. Sleep Paralysis is the inability to move or speak while one is falling asleep or beginning to wake up. During sleep paralysis, the sufferer is consciously aware of their surroundings but is unable to move because the body is still in REM sleep. During REM sleep, the voluntary muscles are "paralyzed" to keep people from being able to act out their dreams. Sleep paralysis usually lasts only a few seconds up to a few minutes with no permanent effects.
Cataplexy. Cataplexy is very similar to sleep paralysis in that there is an involuntary inability to move muscles or speak. While very similar to sleep paralysis in conditions, it is usually onset by varying circumstances. Instead of occurring at the beginning or end of sleep, cataplexy can occur at any time during the waking period and is usually triggered by intense emotions such as surprise, fear, anger, stress, or even humor. Cataplexy can also occur in various degrees of severity ranging from a slight loss of motor functions such as weakness in the muscles or drooping eyelids to a complete loss of muscle tone resulting in physical falls and an inability to move or speak. During cataplectic attacks, sufferers are fully conscious of the event but unable to control it.
Hallucinations. Sufferers of narcolepsy can experience hallucinations during times when they are waking from sleep (hypnopompic) or during sleep onset (hypnogogic). The hallucinations are often very vivid and can even be frightening.
Disturbed nocturnal sleep. It may seem counter-intuitive to believe that sufferers of narcolepsy would have had any trouble sleeping at night, but one of the most common symptoms is fragmented sleep. Just as people with narcolepsy have trouble staying awake during the day, they often have difficulty staying asleep at night. They can wake up to four or five times up to 10 or 20 minutes with no clear reason. Their sleep can be disturbed by insomnia, vivid dreaming, sleep talking, acting out while dreaming, and periodic leg movements.
Causes of Narcolepsy
While the exact causes of narcolepsy are not yet clear, scientists have made headway in identifying neurotransmitters strongly associated with the disorder. In patients with narcolepsy, it has been found that they have significantly reduced levels of the neurotransmitter hypocretin, which promotes wakefulness. In patients with narcolepsy, it has been found that sufferers usually have 90%-95% less hypocretin-producing neurons than patients without the disorder. Exactly what causes the loss of hypocretin-producing cells isn't known, but it is believed to be an autoimmune reaction.
Most sufferers of narcolepsy don't have a family history of narcolepsy, and only about 10% report having close relatives with narcolepsy.
Some rare cases of narcolepsy have been reported as a result of traumatic brain injury to the areas associated with REM sleep, or from tumor growth in the same areas.
Your primary care physician may be able to make a preliminary diagnosis of narcolepsy based on symptoms of EDS and cataplexy. However, for a comprehensive diagnosis of narcolepsy, you will need to have a battery of specialized tests performed at a sleep clinic. The two tests used in conjunction to diagnose narcolepsy are the polysomnogram (PSG) and multiple sleep latency tests (MSLT).
Polysomnogram (PSG). A polysomnogram is an overnight sleep study in which patients have hooked up to a variety of equipment that record brain activity, eye movements, heart rate, blood pressure, oxygen levels, body movement, and more. PSG's are used to document any abnormalities in a patient's sleep cycles. For a PSG used in diagnosing narcolepsy it also helps to rule out any other sleep disorders that may be causing symptoms (such as obstructive sleep apnea causing EDS) or to document any comorbid sleep disorders.
Multiple Sleep Latency Test (MSLT). An MSLT is a sleep study that is performed during the day to measure your tendency to fall asleep during the day and how rapidly you fall asleep. MSLT's generally follow a Polysomnogram and record whether you fall asleep during the test, and if so, which stages of sleep you enter. In an MSLT you are generally given five 20-minute nap opportunities spaced 2 hours apart while a sleep technician monitors your brain activity and eye movements. Patients with narcolepsy often fall asleep and enter REM sleep very quickly.
Treatment of narcolepsy
While currently there is no cure for narcolepsy, with properly diagnosing and treatment of the disorder many of the symptoms can be treated. When cataplexy is a symptom of narcolepsy the loss of hypocretin cannot be reversed and is considered to be life-long, however, with certain drug treatments and lifestyle adjustments cataplexy and EDS symptoms can be controlled.
Stimulants. Drugs are used to stimulate the central nervous system to help people stay awake, and certain amphetamine-like drugs are the most common stimulants prescribed. These stimulants aren't considered as addictive or come with the highs and lows associated with older stimulants. Side effects of stimulant treatment can include headache, nausea, irritability, nervousness, shakiness, heart palpitations, and nighttime sleep disruption.
Antidepressants. Selective serotonin reuptake inhibitors (SSRI's) and serotonin and norepinephrine reuptake inhibitors (SNRI's) have been used to suppress REM sleep, alleviate cataplexy and sleep paralysis and hypnagogic hallucinations. Tricyclic antidepressants have been effective in treating cataplexy. Antidepressants often produce fewer adverse side effects than stimulants, but still come with their own side effects such as impotence, high blood pressure, and digestive problems.
Sodium Oxybate. Sodium oxybate is a strong sedative that is administered at night and helps relieve symptoms of cataplexy and EDS. However, sodium oxybate comes with serious safety concerns and distribution is heavily restricted. Side effects include: nausea, bed-wetting (enuresis), and worsening of sleepwalking. If taken with other medications or alcohol it can lead to breathing difficulties, coma, or even death.
Lifestyle and Home Remedies
Take several short naps a day (10-15 minutes) to alleviate excessive daytime sleepiness.
Keep a consistent sleep schedule. Go to sleep and wake up at the same times every day, including weekends.
Avoid caffeine and alcoholic beverages 2-3 hours before bedtime as these substances can worsen symptoms.
Get regular exercise. Daily exercise 4-5 hours before bedtime can help improve the quality of sleep as well as alleviate symptoms of daytime drowsiness.
Try a relaxing routine just before bedtime. A relaxing bath or reading a good book before bedtime can help promote better sleep at night.
Talk to others about your condition. Having the love and support from those close to you can go a long way in treatment. Furthermore, your coworkers, employers, and teachers should also be aware of your condition to help accommodate your needs. Support groups can also be helpful in connecting with others suffering from the same condition. At support groups, you can also learn about the latest developments in medicine, get coping tips from others, other practical help, and even emotional support.
Be safe. Having a condition in which maintaining wakefulness is difficult can prove to be extremely dangerous. Even during mundane activities like walking downstairs or grilling on a barbecue can quickly become life-threatening if a sleep attack occurs. Driving can be one of the most dangerous activities for sufferers with untreated narcolepsy as those with the disorder are 10 times more likely to have driving accidents than those without it. Work with your doctor to establish a medication time to coincide with your driving schedule. And if at any time you begin to feel excessively sleepy, stop what you're doing and take a nap (if possible) or take an exercise break.
At The Alaska Sleep Clinic, we specialize in treating patients with all kinds of sleep disorders including narcolepsy. If you, or someone you know, may have undiagnosed narcolepsy please contact your primary care physician and see if a sleep study may be needed to diagnose your disorder. While there is no cure for narcolepsy, the treatments available can help relieve you of many of the symptoms giving you a more wakeful, fulfilling life. For more information about narcolepsy or any other sleep disorders feel free to contact us by clicking the link below.