In narcolepsy, nighttime REM sleep is disturbed. The aspects of REM sleep are then displaced and sometimes they are experienced separately. This phenomenon is confusing to the patient and makes diagnosing narcolepsy difficult for the physician.
Main Aspects of REM Sleep
REM usually takes about 90 minutes to occur and lasts around 10 minutes. NREM or Non-Rapid Eye Movement sleep occurs before REM in normal healthy sleep cycles. In Narcolepsy, REM sleep can occur much faster, sometimes even as soon as the patient falls asleep. This is referred to as Sleep Onset REM or SOREM.
- Physical Sleep
During REM sleep, the body loses muscle tone and falls “asleep” It is slack and is completely relaxed.
- Mental Sleep
When unconsciousness is achieved, this is mental sleep. This aspect of sleep is the most widely used to define the act of sleeping.
- Dreams
REM or Rapid Eye Movement is an expression used to describe the physical marker for dreaming. Dreams occur when the body is in a complete sleep state.
- Vital Signs
Breathing and heart rate becomes erratic during REM sleep. Even though the major muscle groups are paralyzed, brain activity is heightened and vital signs reflect this activity.
Symptoms of Narcolepsy
As explained earlier, in narcolepsy, REM sleep is dysfunctional. The symptoms of narcolepsy have clear similarities to the normal aspects of REM sleep or are directly related to the disruption of REM sleep, as in the case of Excessive Daytime Sleepiness or EDS.
- EDS
EDS is exactly what it sounds like, the patient experiences an excessive desire to sleep that tips the border into need. Narcolepsy patients do not sleep more than people with healthy sleep habits; they have interrupted nighttime sleep, or suffer from insomnia. EDS is the result of the bodies needs to make up for the loss of sleep.
People who experience EDS tend to fall asleep at unexpected and sometimes dangerous times, like while driving a car. EDS is not really random. It often occurs after meals or during times when there is little stimulation. Relaxed settings are the bane of the narcoleptic. EDS can be embarrassing for many patients, especially if the uncontrollable sleep attack strikes at a particularly inappropriate time like during a history lecture or while on a date at the movies.
A mild symptom of EDS can be treated with simple lifestyle changes such as adhering to stricter bedtimes scheduling daytime naps and dietary changes like lighter, more frequent meals.
When EDS is more severe, doctors may add stimulant drug therapies to the treatment. Drugs used to treat EDS are: Methylphenidate, Amphetamine, Modafinil or Selegiline. When drug treatment is necessary, lifestyle changes are still utilized to optimize the effects. When carefully managed, a person with EDS can generally enjoy a normal life.
The most common displaced aspect of REM sleep narcolepsy patients experience is the sudden and complete loss of muscle tone and control. Cataplexy is experienced by seventy percent of people with narcolepsy.
Cataplexy occurs when the patient experiences strong emotion. Anger and hearty laughter are reported as the biggest triggers for cataplectic episodes.
Narcolepsy with cataplexy can also have mild symptoms. Sometime the episode gets filed as “gee, I am clumsy today” or is a barely perceptible drooping of an eyelid. Cataplexy often affects the face and head. Sometimes a sudden loss of muscle control in the neck will cause the head to flop forward. It can be as fast as a few seconds and go unnoticed.
Cataplexy can also have severe episodes. During one of these attacks, a subject can lose complete control and collapse; it can last over an hour. An interesting aspect of cataplexy is that the person who suffers from it is completely alert and awake during the whole thing.
Sometimes, antidepressants are given for cataplexy, but the only drug that is approved by the FDA to treat the symptom of cataplexy gamma-hydroxybutyric acid (GHB). It is produced for theUSas sodium oxybate, and packaged under the brand name Xyrem.
Sodium Oxybate is a highly effective sedative and paradoxically, it is a stimulant at low doses. It is a highly controlled substance as it is a heavily abused chemical. It has been used as a date rape drug and as it stimulates the production of the human growth hormone, it is abused by body builders as well. It is, however, highly effective in the treatment of both EDS and cataplexy
- Sleep Paralysis
Like cataplexy, an episode of sleep paralysis affects muscle control and tone. Unlike cataplexy, Sleep paralysis is always complete paralysis, never partial. And it is not determined by strong emotion. Instead, sleep paralysis is experienced during the twilight between wake and sleep. And it is often accompanied by hallucinations.
Sleep Paralysis is not strictly a narcolepsy symptom. Anyone can experience sleep paralysis. Many people do have one or two episodes during their life. It is more common in youth. Narcoleptics that have sleep paralysis as a symptom experience it more regularly.
Antidepressants are sometimes effective treatment for sleep paralysis and so is sodium oxybate.
- Hallucinations
The experience of hallucinations makes narcolepsy a sometimes terrifying situation. Hallucinations can be experienced with other symptoms of narcolepsy or independent of them.
Hallucinations are like the waking dreams of REM sleep and in the case of sleep paralysis; they can appear dark and sinister giving the sufferer a feeling of detachment. Historically, hallucinations that were experienced during sleep paralysis would sometimes be misdiagnosed as paranormal occurrences such as possessions or out of body experiences.
Often, narcolepsy patients who suffer from hallucinations have a weak or unstable handle on reality. A misdiagnosis of schizophrenia is sometimes made when reality becomes hazy for the patient.
Conclusion
Disturbed REM sleep and narcolepsy disorder are found hand in hand in the sleep clinic and while several things can cause disturbed REM cycles, Narcolepsy is always affected by them.