Narcolepsy and Overwhelming Daytime Sleep Disorder
NARCOLEPSY is a sleep disorder. The principal symptoms are excessive daytime sleepiness (EDS), cataplexy (loss of muscle tone), hallucinations, sleep paralysis and disrupted night-time sleep. Clinics also diagnose Narcolepsy by measuring how quickly the patients falls asleep and how often rapid eye movements are present at or near the onset of sleep.
Excessive daytime sleepiness occurs everyday, regardless of the amount of sleep obtained at night. EDS is usually experienced as a heightened sensitivity (sometimes as an almost irresistible susceptibility) to becoming sleepy or falling asleep, especially in sleep - inducing situations. Patients describe the problem as sleepiness, tiredness, lack of energy, exhaustion or a combination of these feelings, either continuously or at various times throughout the day.
Sometimes sleepiness occurs so suddenly and with such overwhelming power that it is referred to as a ’sleep attack’. Some patients have several ‘attacks’ each day, which usually last for less than 30 minutes, but sometimes the patient stays asleep for several hours.
Cataplexy is an abrupt loss of voluntary muscle tone, usually triggered by emotional arousal. Attacks can range in severity from a brief sensation of weakness to total physical collapse lasting several minutes. Hallucinations are intense, vivid, sometimes accompanied by frightening auditory, visual and tactile sensations, and occur just on awakening or falling asleep. Occasionally they are extremely difficult to distinguish from reality. Sleep paralysis is momentary inability to move when waking up or falling asleep. This condition can by terrifying, especially if it occurs with a frightening hallucination.
Scientists do not know what causes Narcolepsy, but they think it may be due to a biochemical imbalance of the central nervous system. The disorder, is often concentrated in families and Narcolepsy, or predisposition to it, may be an inherited condition.
While statistics on the prevalence of Narcolepsy are difficult to obtain, the estimated number of cases in Australia is between 5000 and 16,000.
Progress Of Symptoms
Narcolepsy is a lifelong illness, however, no know cure has been confirmed. Typically, symptoms (usually EDS) first become noticeable between the ages of 1 and 30. Symptoms may be subtle at first but become increasingly severe over the years. Patients usually learn to pinpoint conditions likely to induce sleep or cataplexy and they try either to avoid such condition or, with proper medication, control the symptom. Control is especially important when patients are driving or engaging in other potentially dangerous activities. Of itself, Narcolepsy is not life threatening and does not affect longevity.
Social Complications
The mild early symptoms of Narcolepsy may cause no more than minor inconveniences. As they become increasingly severe, however, symptoms cause greater disruptions in patients’ social and professional lives and may become profoundly disabling. EDS often occurs at inopportune times - in the classroom, business meetings, during a meal or even in the middle of a conversation. Learning, for children and adults alike, may be hampered because the abilities to read study and concentrate are periodically (or in some cases continuously) impaired. Parents, teacher spouses and employers often mistake the patient sleepiness for lack of interest or misconstrue it as sign of hostility, rejection or laziness.
Cataplectic attacks commonly occur in situations involving perfectly normal emotions such as humor (hearing or telling a joke), competitiveness (bidding a game of bridge), excitement (viewing or especial participating in a sports event) and stress or self assertion.
Patients’ efforts to stave off catapletic attacks by avoiding these emotions may greatly diminish the quality of their lives and they may become severely restricted emotionally.
Diagnosis
Although symptoms are usually clear cut, many patients have Narcolepsy for 10 to 15 years before the disorder is correctly diagnosed. For one thing, patients may not suspect a medical disorder and usually do not seek help until symptoms become quite severe. Also, physicians often misdiagnose Narcolepsy, mistaking the symptoms for those of other disorders, like depression. Sometimes the sleepiness is thought to be a side effect of medication. Cataplectic attacks also have been misdiagnosed as epileptic seizures, even though Narcolepsy is not a form of epilepsy and requires different treatment. Narcolepsy can be confirmed or ruled out by a test (polysomnography) given in a sleep disorders clinic or laboratory under carefully controlled conditions. People with Narcolepsy may be under the care of a neurologist.
Treatment
Although there is no known cure for Narcolepsy, several drugs help to control the symptoms. Stimulants are usually prescribed to treat EDS and sleep attacks and certain anti-depressants help control the cataplexy, sleep paralysis and hallucinations. Patients taking either drugs should have their blood pressure regularly checked. Narcolepsy symptoms vary from person to person, as does response to medication. Also both symptoms and response are likely to change gradually over time. The proper choice of medication and dosage requires careful attention to the patient’s need and responses, and close co-operation between patient and physician. Medications used to treat Narcolepsy usually have some undesirable side effects, in some cases, serious enough to preclude drug treatment. However, for most patients medication is helpful.
Patients must make adjustments to their lifestyle to accommodate the condition. Monotonous, boring work should be avoided and preference given to occupations involving physical movement and fresh air.
Rotating shift work is unsuitable and operating dangerous machinery should be completely avoided. Driving should only be attempted if the condition is under control and stable on treatment. Regular naps at least twice a day or even more on weekends are helpful. Large meals should also be avoided and smaller, more frequent, low carbohydrate meals substituted. Regular sleep hours and avoidance of sleep deprivation are very Important.
Research
Many research opportunities hold promise for people afflicted with Narcolepsy. Basic research on how the brain regulates sleep is under way in several laboratories around the world. Animal models with naturally occurring symptoms identical to the human form of Narcolepsy have been discovered. These models will enable scientists to probe brain anatomy, physiology and biochemistry more extensively than is possible with human patients.
Of particular interest in Narcolepsy is the brain chemical acetylcholine. This chemical regulates rapid eye movement (REM) sleep, the sleep state associated with dreaming. Natural events that take place during normal REM sleep parallel Narcolepsy symptoms: the body becomes immobile as in sleep paralysis; muscle tone decreases as in cataplexy; and dreaming similar to hallucinations occurs. Narcoleptic sleep attacks are in fact the inappropriate appearance of REM sleep.
www.dircsa.org.au/docs/narcol.htm last updated 8 May 2001
NARCOLEPSY
Fact Sheet
Narcolepsy and Overwhelming Daytime Sleep Society of SA Inc
Diagnosis
Although symptoms are usually clear cut, many patients have Narcolepsy for 10 to 15 years before the disorder is correctly diagnosed. For one thing, patients may not suspect a medical disorder and usually do not seek help until symptoms become quite severe. Also, physicians often misdiagnose Narcolepsy, mistaking the symptoms for those of other disorders, like depression. Sometimes the sleepiness is thought to be a side effect of medication. Cataplectic attacks also have been misdiagnosed as epileptic seizures, even though Narcolepsy is not a form of epilepsy and requires different treatment. Narcolepsy can be confirmed or ruled out by a test (polysomnography) given in a sleep disorders clinic or laboratory under carefully controlled conditions. People with Narcolepsy may be under the care of a neurologist.
Treatment
Although there is no known cure for Narcolepsy, several drugs help to control the symptoms. Stimulants are usually prescribed to treat EDS and sleep attacks and certain anti-depressants help control the cataplexy, sleep paralysis and hallucinations. Patients taking either drugs should have their blood pressure regularly checked. Narcolepsy symptoms vary from person to person, as does response to medication. Also both symptoms and response are likely to change gradually over time. The proper choice of medication and dosage requires careful attention to the patient’s need and responses, and close co-operation between patient and physician. Medications used to treat Narcolepsy usually have some undesirable side effects, in some cases, serious enough to preclude drug treatment. However, for most patients medication is helpful.
Patients must make adjustments to their lifestyle to accommodate the condition. Monotonous, boring work should be avoided and preference given to occupations involving physical movement and fresh air.
Rotating shift work is unsuitable and operating dangerous machinery should be completely avoided. Driving should only be attempted if the condition is under control and stable on treatment. Regular naps at least twice a day or even more on weekends are helpful. Large meals should also be avoided and smaller, more frequent, low carbohydrate meals substituted. Regular sleep hours and avoidance of sleep deprivation are very Important.
Research
Many research opportunities hold promise for people afflicted with Narcolepsy. Basic research on how the brain regulates sleep is under way in several laboratories around the world. Animal models with naturally occurring symptoms identical to the human form of Narcolepsy have been discovered. These models will enable scientists to probe brain anatomy, physiology and biochemistry more extensively than is possible with human patients.
Of particular interest in Narcolepsy is the brain chemical acetylcholine. This chemical regulates rapid eye movement (REM) sleep, the sleep state associated with dreaming. Natural events that take place during normal REM sleep parallel Narcolepsy symptoms: the body becomes immobile as in sleep paralysis; muscle tone decreases as in cataplexy; and dreaming similar to hallucinations occurs. Narcoleptic sleep attacks are in fact the inappropriate appearance of REM sleep.
*Source: Narcolepsy and Overwhelming Daytime Sleep Society of SA Inc (NODSS SA Inc)
