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Narcolepsy is a lifelong disorder which may entail serious disablement. It is estimated to afflict more than 20,000 people in the United Kingdom many of whom are undiagnosed. No cure for Narcolepsy is yet known and no wholly adequate treatment is available.
The cause is suspected to be a central nervous system defect but the exact mechanism is not clearly understood. There is no evidence of a psychological cause.
Narcolepsy (or a predisposition to develop it) may be an inheritable characteristic passed down in families.
The symptoms usually appear independently of one another. Typically, they are rather mild at the start and increase in severity at a gradual rate over a period of years. However, the development and the severity of symptoms are very variable in different individuals.
The two primary symptoms of narcolepsy are excessive daytime sleepiness
and cataplexy. In severe cases either can result in complete disability. The other
symptoms appear less frequently than the primary symptoms and usually present no serious
problems. They are sometimes experienced by people who are not narcoleptic.
EXCESSIVE DAYTIME SLEEPINESS (EDS) is usually the
first symptom to be noticed. It may take the form of sleepiness, tiredness, lack of
energy, or irresistable bouts of sleep. Although this pathological sleepiness is evident
every day, its intensity varies through the day and the person suffering from it may find
only the more severe episodes troublesome. Over twenty four hours the total time sleeping
is usually no more than what is normal. The abnormality lies in the continuous
susceptibility to sleepiness or to falling asleep and the circumstances in which this
occurs.
CATAPLEXY, the other primary symptom, is a brief, but sudden loss of voluntary
muscle control usually triggered by emotions, such as those associated with laughter,
anger, elation or suprise. The severity and extent of a 'cataplectic' attack can vary from
a fleeting sensation of weakness, extending more or less throughout the whole body, to the
noticeable involvement of several muscle groups or to a state of absolute powerlessness
involving almost all the voluntary muscles.
EXCESSIVE DAY-TIME SLEEPINESS (EDS)
As a general rule, EDS developes slowly and in some cases several years pass before it becomes a problem. It usually starts with gradually increasing sleepiness, especially when the person affected is sitting or reclining, and a pronounced tendency to fall asleep in situations that many normal people also feel sleepy or fall asleep in, for instance: after meals and in monotonous circumstances like listening to a dull lecture. In time, the sleepiness and sleep 'attacks' begin to occur in less appropriate situations, like travelling in a car or watching a favourite television programme, reading a newspaper, writing a letter, watching a sports match or waiting for an interview. Finally, the person will begin to fall asleep at quite innapropriate times, for instance: while driving (very typical is dozing off while waiting for a traffic signal to change), or in the middle of a conversation, even in mid-sentence. If the person is not in a position suited to sleeping, sleep will typically last only a few seconds or minutes. Otherwise sleeping for a quarter or half and hour is common and even longer 'naps' are not unusual.
Sometimes sleep occurs with little or no warning. At other times the approach of an attack can be detected and the attack resisted, sleep being put off for minutes or even hours. Some people always have warning in advance, some occasionally, and others never. A narcoleptic finds it as difficult to resist falling asleep as a normal person does when s/he has been deprived of sleep. Unfortunately, a narcoleptic has the problem no matter how much sleep s/he has at night. Even if an attack is resisted successfully the person affected is likely to remain very sleepy and susceptible to falling asleep very easy.
Sleepiness in narcoleptics may range from a feeling of alertness and complete wakefulness for most of the day, with only occasional brief episodes of sleepiness, to continuous tiredness and a continual fight against falling asleep. In some, sleep attacks are followed by periods of complete alertness, whereas in others, periods of sleep never fully relieve the feeling of tiredness and lack of energy.
After a sleep attack, the narcoleptic may not realise that s/he has been asleep, and if
the attack has interrupted a conversation s/he may try to continue it. S/he may also have
had a dream so vivid that, on waking, s/he may mistake it for a real event. These can be
upsetting and confusing experiences.
During an attack vision may become blurred and speech difficult, or impossible. Sagging of the jaw and tilting of the head are common and frequently accompanied by slight buckling of the knees. Sometimes an attack will be marked by convulsive jerking, caused by the muscles alternating rapidly between limpness and partial control.
The attacks can be caused by emotion, stress, or fatigue. The most common cause is emotion and the emotions most frequently responsible are anger and thoses associated with laughter. However, attacks can also be induced by elation on reading a book or watching a film. In some cases merely recalling a funny or happy situation, or thinking about an emotionally charged situation, like presenting a differing opinion or asking for a rise, is enough to bring cataplexy on. Obviously, guarding against cataplexy by avoiding such thoughts is emotionally restrictive.
Another emotion which brings on cataplexy in some is athletic exhilaration. Many narcoleptics cannot participate in sports, because making an all-out physical effort risks their losing muscle control in mid-stride and suffering a severe fall. (Strangely enough falling injuries are rare, perhaps because some ability to anticipate or control a fall is retained. Some people learn to tense their muscles, lock their knees, and select a nearby support prior to an attack). Inability to make a telling stroke is particularly limiting: the anticipatory elation aroused, triggers an attack and the player is often incapable of making any stroke at all, let alone the ace or smash s/he envisaged. Exactly the same effect inhibits witty or telling remarks in conversation or debate (It is possible to guard against this by ‘locking’ the mind as one locks the muscles to prevent a fall, but the degree of concentration and watchfulness needed can not always be commanded).
In a person who is sitting or reclining, a cataplectic attack, may gradually develop into a sleep attack. However, the major distinction between the two symptoms is that awareness of one’s surroundings is maintained during cataplexy, but not during a sleep attack. People normally remember sounds and words spoken during a cataplectic attack, even though they appear to be unconscious during it. However, they will not remember anything that went on around them during a sleep attack. If a person’s eyes are open during a cataplectic attack, he will usually be able to follow external motions, such as those of a hand passed in front of the eyes.
AUTOMATIC BEHAVIOUR
Automatic behaviour refers to activity (usually of a routine kind), carried on with greatly reduced awareness and little intelligent control. Generally, details of the activity cannot be recalled and the person affected may think that s/he has suffered a blackout. Cases have been reported of individuals setting out to drive somewhere and on reaching their destination, whether the one intended or another, being quite unable to recall how they reached it. A typical experience is driving home after work and coming to, to find oneself in the wrong part of town or parked in a neighbour’s driveway. Another is putting dirty dishes in a washing machine or drier, turning it on, and awakening to the sound of them breaking. Writing meaningless sentences and interjecting unrelated subjects into a conversation are also common.
SLEEP PARALYSIS
Sleep paralysis is an ability to move on falling asleep or awakening. Inability to
speak or to open the eyes accompanies it. Usually, awareness and recall are total but
occasionally hallucination occurs. The experience is generally uncomfortable and quite
frightening, presumably because of the feeling of complete helplessness engendered. Sleep
paralysis is estimated to occur, at least occasionally in up to half of the normal
population and is quite natural. It prevents the sleeper acting out a vivid dream and so
exposing himself to harm.
HYPNAGOGIC HALLUCINATIONS
These are exceptionally vivid experiences indistinguishable from reality occuring at
the beginning of sleep, whether by day or by night. They are often accompanied by
paralysis and by awareness of some threatening figure, or event in the vicinity, which may
induce terror. Typically, the sleeper may be convinced of the presence of a malevolent
intruder, a monster, a savage animal, a snake or another human being. The threatening
aspect may be confined to noises, like the sound of footsteps, or of glass breaking. Less
frequently, some other environmental features in the hallucination. Hypnagogic
hallucinations are occasionally experienced by normal people without narcolepsy, but these
experiences, known as ‘hypnagogic reveries’ are usually less intense.
DISRUPTED NOCTURNAL SLEEP
This refers to repeated wakefulness in the night. The immediate cause may be a
frightening dream, a need to empty the bladder, or a temporary suspension of breathing
(See Sleep Apnoea below). Awakening may occur without evident
cause. It is often accompanied by agitation, feeling hot, or an urge to eat (especially a
craving for sweets).
SLEEP APNOEA
The cessation of breathing mentioned before is termed Sleep Apnoea. It is not itself a
symptom of narcolepsy, but about twenty per cent of narcoleptic males experience it.
Breathing is suspended for twenty seconds to two minutes at a time and may not be resumed
until the sleeper is half awake. The cycle: sleep - suspension of breathing - half awake -
resumption of breathing - sleep, may be repeated hundreds of times during the night,
usually accompanied by loud grunts and snores.
AGE OF ONSET OF NARCOLEPSY
In approximately fifteen per cent of diagnosed cases narcolepsy sets in before the age
of fifteen whereas in some sixty per cent it occurs between the ages of fifteen and
thirty. It is uncommon for onset to take place after the age of forty. Sleep attacks and
daytime sleepiness usually appear first, followed in a few years by cataplexy. However, in
some cases sleepiness, sleep attacks, and cataplexy appear simultaneously while in others
cataplexy makes its appearance first.
PROGRESS OF SYMPTOMS
Once a person has narcolepsy, s/he almost always has it for life. The severity of
symptoms tends to change very slowly. The symptoms often seem to become less severe in
middle age, but the apparent improvement may only be illusory, being based on the ability
of narcoleptics to learn mastery of their emotions and better management of their
symptoms, rather than on a real remission of the disorder.
THE OUTLOOK FOR A NARCOLEPTIC
At first, the symptoms are barely distinguishable from what healthy people occassionaly experience, but as the disorder develops they come to be perceived as clearly abnormal.
The degree to which they interfere with the life and activity of the narcoleptic depends as much on the occupational and social demands made by his/her way of life as on the severity of the brain malfunctions.
Although a narcoleptic could become unemployable, socially isolated, and acutely depressed, such extreme effects can be mitigated. Adjusting lifestyle and creating an unprediced attitude at work and at home make it possible for the narcoleptic to lead a near normal life.
In more severe cases that end can be achieved by continuous medication tailored to
individual needs. Narcolepsy neither shortens the lifespan nor impairs the
narcoleptic’s inherent mental and physical capabilities.
HOW RELATIVES CAN HELP
The behaviour of relatives and friends critically affected the narcoleptics ability to cope with the disorder and get a sense of isolation can develop if the narcoleptic continually meets with misunderstanding of his condition. This is particularly true of children who do not have the experience of adults or their self-confidence in the face of adversity.
Narcolepsy being an organic disorder, it is quite wrong to regard the sleepiness as a manifestation of laziness or malingering. When a narcoleptic drops off it is not due to lack of interest, but because he is quite incapable of resisting the urge to sleep.
Nor are there grounds for assuming that a narcoleptic is mentally or emotionally ill. Even during a cataplectic fit the sufferer reasons quite normally.
Victims of cataplexy may need support to prevent their falling but no other help or professional medical care is needed. Although it is disconcerting to witness such a fit the victim will recover very quickly.
During automatic behaviour the narcoleptic is unaware of what is happening. Apparent
forgetfulness is a common result. One should watch for signs of automatic behaviour
(eyelids lowered, eyes glazed, apparent inattention) and be ready to arouse the
narcoleptic if it perceived that s/he is exposed to risk.. e.g. when using a power tool or
driving.
PREVALENCE AND CAUSE
The number of people who have narcolepsy is not known for certain, but is estimated to be between, a fiftienth (0.02) and a tenth (0.01) of one per cent, of the population. Consequently, there are probably fifty thousand to a quarter of a million narcoleptics in the United States. For comparison there are a hundred thousand cases of chronic nephritis and seventy thousand cases of multiple sclerosis in the same population. In the U.K. one usually speaks in terms of twenty thousand narcoleptics, but this number is only surmised. One thing is certain, whatever the true figure may be, it is many times greater than the number of cases actually diagnosed.
Several studies have shown that narcolepsy is concentrated in families. Relatives of those with narcolepsy seem to be up to two hundred times more likely to develop narcolepsy, than the population at large. One study of some two hundred and fifty to three hundred cases, showed that fifty four were concentrated in nineteen families, with two to eight cases in each. This does not mean that the children of a narcoleptic parent are sure to develop narcolepsy. It only indicates that children of a narcoleptic parent have a greater tendency to narcolepsy than other people.
It was once believed that narcolepsy was a psychological problems with a psychological
cause. However, research has disproved this theory and it is now believed that narcolepsy
is a neurological disorder, with an impairment of the sleep/wake regulatory mechanism as
the prime cause.
SOCIAL COMPLICATIONS
Narcolepsy can disrupt educational and social life to an extraordinary extent. The
ability to read, study and learn are impaired, perhaps markedly. Not only parents,
husbands and wives, but also teachers and even physicians are often confused about the
cause of the symptoms, often mistakenly attributing the sleepiness to lack of motivation.
A husband or wife will complain that the partner responds to attempts at conversation or
more intimate overtures, by falling asleep and will misinterpret the sleepiness as a sign
of rejection or hostility.
SECURING A DIAGNOSIS
Obtaining an accurate diagnosis of narcolepsy from a local doctor is not always easy. One study of narcoleptics, revealed that on average, fifteen years intervened between the appearance of the symptoms and the first correct diagnosis! Why? In part, the answer may be the subtlety of the initial symptoms and the gradualness of their growth in severity. At first, the symptoms hardly seem abnormal and as they slowly become more severe, people become accustomed to them and adjust their lives to accommodate them. Often, they continue to do so until the symptoms’ severity compels attention. When they seek medical attention, they may complain of unusual tiredness, or difficulty in staying awake, but fail to mention other symptoms, perhaps because they do not know that the sleepiness and sleep attacks are related to the other symptoms. So failure to obtain and early and accurate diagnosis may be caused by the patient’s failure to report all the symptoms.
A second obstacle to securing an accurate diagnosis is the problem of finding a doctor
who is sufficiently knowledgeable to be able to identify narcolepsy. This problem was
demonstrated by a study of the first fifty patients diagnosed by the Sleep Disorder Clinic
of Stanford University. The average number of doctors consulted before the patients were
diagnosed accurately, was four and a half! Therefore, it is essential that a person who
suspects the presence of narcolepsy should identify a competent doctor. How does he go
about doing so? The patient may ask his doctor frankly, whether ha has expertise in
narcolepsy and whether he has any other narcoleptic patients. If the doctor is not
experienced in treating narcoleptics, or if the narcolepsy is not of interest to him, it
is reasonable to ask him to suggest another doctor (preferably a local neaurological
specialist), who has interest, experience, and expertise in the diagnosis and treatment of
narcolepsy.
LABORATORY TESTS
Diagnosis of narcolepsy may be made by means of a clinical sleep laboratory test under carefully controlled conditions. During the test the electrical signals present at various places on the patients body, notably the scalp, are recorded by means of leads attached to the patient which are easy to remove after the test. Gelatinous paste is employed to ensure a good contact. The patient is asked to lie daown and take a nap while the recording is made.
The recording of rapid eye movements is particularly significant. In normal persons, the sequence of events is always wakefulness to sleep, with the maintenance of muscle activity and the absence of rapid eye movements (NON-REM) during approximately the first 60 minutes of a sleep period. In the narcoleptic it is typical for the first event to be a complete suppression of normal muscle activity, followed quickly by rapid eye movements. This is known as sleep onset REM or SOREM.
If a person has narcolepsy, and especially if he has experienced both sleep attacks and
cataplexy, the diagnosis may be established very quickly with the sleep onset REM activity
appearing during the first or second recording. In some cases, however, it may not appear
until later. A continuous 36 hours recording may be conducted. If no SOREM periods occur
during that time it is generally assumed that the patient does not have narcolepsy but one
must be aware of the fact that false negatives do occur.
TREATMENT
Although there is no cure at present for narcolepsy, the symptoms can be assuaged or even suppressed by drugs. First, however, all practical steps should be taken to change working habits and lifestyle, in particular by:
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Avoiding occupations that involve long periods of
concentrated attention and physical immobility, especially in an environment that is
poorly lit or ventilated. |
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Avoiding shift work and irregularity of retiring and rising
times. |
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Opting for jobs without monotony and in which brief naps and
breaks are feasible. |
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Avoiding excess alcohol and heavy meals and generally
keeping one’s weight down. |
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Adopting a routine of brief naps during periods of
diminished alertness and of breaks in the open air or vigorous physical activity to
maintain alertness at other times. |
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Learning to recognise and avoid situations conductive to
cataplectic attacks. |
If the narcoleptic keeps to these guidelines the physician can devise an effective regime of medication with minimal side-effects. Treatments depends on the patient’s symptoms and history of therapy. Some have more cataplexy, others more sleep attacks and different treatments are indicated for each, but the essential is that treatment be tailored to the individual. Stimulants are used to treat sleepiness and sleep attacks. A different group of drugs is used to treat cataplexy. All the drugs have side effects, which have to be taken into account, when choosing a particular compound and fixing the daily dose. Withdrawal of medication is sometimes necessary, because either tolerance has developed, or the doses needed to deal with the symptoms effectively, are too large. Withdrawal must not be sudden and like re-evaluation of therapy, must be supervised by a specialist doctor.
No one drug exists which can deal with all the symptoms. Stimulants amphetamines, methyl phenidate, mazindol, or premoline) are prescribed to combat sleepiness, and antidepressants (cloripramine, imipramine, protyptilline, or viloxazine) to control cataplexy.
Stimulants should not be taken late in the day because by causing sleeplessness at
night they increase sleepiness the next day. One also has to take care with some drugs
which tend to raise blood pressure.
My Other Pages relating to Narcolepsy
Click here to visit Medication For Narcolepsy
Click here to visit the Sleep Apnea
Page
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site is under construction, some of these links are not up and running as yet.. but
hopefully they soon will be.
Links to other Sites and Pages that I have found of great help
Stanford University for Narcolepsy - http://www.med.stanford.edu/school/Psychiatry/narcolepsy/ RXmed - http://www.rxmed.com/index.html
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This page was created 22 May 1999
Page was last updated 16th October 2002