An Introduction To Narcolepsy And Daytime Sleepiness

A sleep disorder is a physical and psychological condition or disturbance of sleep and wakefulness caused by abnormalities that occur during sleep or by abnormalities of specific sleep mechanisms. Although the sleep disorder exists during sleep, recognizable symptoms manifest themselves during the day. Accurate diagnosis requires a polysomnogram, widely known as a "sleep test."

It is estimated that some 40 million Americans suffer from chronic, long-term sleep disorders. Another 20 to 30 million Americans suffer from some kind of sleep disorder on an irregular basis. The annual costs in productivity, health care, and safety have been estimated in the billions of dollars.

• What Is Narcolepsy?
• How Common Is Narcolepsy?
• What Is The Cause Of Narcolepsy?
• When Should I See A Doctor?
• What Is The Treatment For Narcolepsy?

What is Narcolepsy?

Narcolepsy is a neurological condition that causes patients to have excessive sleepiness during the day combined with recurring episodes of naps, particularly at inappropriate times. Narcoleptics usually first complain of feeling sleepy or tired all the time. Consequently, sufferers tend to fall asleep during the situations when most people would remain awake, like watching an exciting movie or driving. Narcolepsy can be an extremely dangerous disorder, primarily because the narcoleptic falls asleep at inappropriate times.

Narcoleptics usually experience one or more of the following four symptoms: excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic hallucinations. Symptoms can appear all at once or develop slowly over many years.

Cataplexy is a temporary decrease or complete loss of muscle control triggered by a strong emotion such as laughing, anger, or surprise. It can range from a weakness in the knees to a complete "rag doll" collapse to the ground. Patients, while essentially paralyzed, are fully conscious during these attacks. The frequency of cataplexy attacks varies by patient, but they usually do not last more than a few minutes.

Narcoleptics may also suffer from sleep paralysis, a brief loss of muscle control that occurs as they are drifting to sleep or awakening. While somewhat aware of the surroundings, patients are unable to move or speak. Paralysis usually disappears when the person is touched. Forty to 65% of narcoleptics experience sleep paralysis.

Vivid dream-like images and sounds experienced at sleep onset, called hypnagogic hallucinations, may also affect a person with narcolepsy. These visions can be very frightening because the person is partially awake, but unable to control the event. Emotions that usually accompany these images are fear, anxiety, and dread. Hypnagogic hallucinations affect between 50 to 70% of narcoleptic patients.

Another symptom of narcolepsy may include automatic behavior, or performing tasks and activities without recollection of the event. Essentially, it is a "black out" during wakefulness; the person may actually be asleep with his or her eyes open. Repeated nighttime awakenings, double vision, trouble concentrating, and memory loss are also common symptoms of narcolepsy.

How Common Is Narcolepsy?

Narcolepsy is a fairly uncommon sleep disorder - 1 in 2,000 Americans suffer from it. However, the Center for Narcolepsy at Stanford Medical School claims that it is a greatly underdiagnosed illness.

Narcolepsy usually begins in late childhood or early adolescence. It has been estimated that the average amount of time it takes to accurately diagnose narcolepsy is 14 years. Thus, the other consequence of narcolepsy is the emotional toll on family and interpersonal relationships, and the personal toll in education and professional endeavors.

What Is The Cause Of Narcolepsy?

Physicians are still puzzled over the exact cause of narcolepsy. Epilepsy, as was once thought to be the cause, has since been ruled out. Research indicates that narcolepsy is a genetically-linked disorder. People with a relative who has narcolepsy are 60 times more likely to be at risk. Narcolepsy is a disorder of the part of the central nervous system that controls sleep and wakefulness and may also be associated with the immune system.

When Should I See A Doctor?

If a person suspects the symptoms of narcolepsy, a visit to a sleep specialist is recommended. As with all sleep disorders, the physician will thoroughly review the patient's medical history and perform a complete physical examination.

Two tests, a polysomnogram and multiple sleep latency test (MSLT), may be performed to confirm the presence and severity of narcolepsy. The results of both tests will help determine an exact diagnosis of narcolepsy, since people with narcolepsy arrive at REM sleep much faster than normal.

A polysomnogram will help determine if another factor is contributing to the symptoms of narcolepsy. During a polysomnogram, the patient is asked to spend a night in a sleep center. Small electrodes are placed in different places on the body to monitor brain waves, heart rate, eye movements, and muscle activity. The next day, the MSLT is performed. While the electrodes are still attached, the patient is asked to take 4 or 5 20-minute naps at two-hour intervals. This test reveals how quickly the patient falls asleep and whether they progress to REM sleep.

What Is The Treatment For Narcolepsy?

Presently, there is no cure for narcolepsy. However, doctors can effectively treat the symptoms with medication, behavior modification, and management of the patient's environment. Keeping the patient as alert as possible during the day and minimizing the symptoms of cataplexy, hypnagogic hallucinations, and sleep paralysis are the goals of treatment.

Medication

Most over-the-counter medications containing caffeine are not effective for narcoleptic patients. Treatment of daytime sleepiness is usually isolated from other symptoms of narcolepsy. Daytime sleepiness is treated with prescription stimulants, such as Ritalin or Dexedrine. In January 1999, the first non-amphetamine sleep prevention drug, called Provigil (modafinil), was FDA approved for use in treating sleepiness in narcolepsy patients.

Antidepressants and serotonin reuptake inhibitors are typical medications for reducing cataplexy and other primary symptoms. These drugs slow down the central nervous system. Selective serotonin reuptake inhibitors (SSRI) are a class of antidepressants that assist nerve impulses along pathways using the neurotransmitter serotonin. Xyrem (gamma-hydroxybutyrate) is an antidepressant that is still being studied in clinical trials. Preliminary results show that Xyrem is safe and effective for treating cataplexy, hypnagogic hallucinations, and sleep paralysis. FDA approval is expected in a few years.

The correct dose and combination of medications can result in symptom control and minimal side effects. While on certain medications and suffering from a sleep disorder, avoiding sleeping pills and alcohol are imperative.

Behavior Modification

Lifestyle changes are necessary for adequate control of narcolepsy. Patients are urged to follow a regular sleep/wake schedule, as well as establish good sleep hygiene in general. Doctors often recommend that narcoleptics take brief, voluntary naps (clinically called "nap therapy") throughout the day to help them stay alert. Additionally, extreme caution should be taken during potentially dangerous activities, such as operating machinery.

Management of Environment

A good support system of family, friends, and co-workers is also invaluable; employers who make allowances for the narcolepsy sufferer are usually rewarded with greater productivity. In addition, narcolepsy web sites and support groups exist for sharing frustrations and experiences. Those who understand the disorder realize the person's behavior is not willful or psychotic.