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The 22nd September each year is World Narcolepsy Day. The aim of the day is to raise awareness for this rare disorder and to enable those who have narcolepsy to share their stories on social media. Professionals and organisations unite the international narcolepsy community to hold various events on this day to increase public knowledge across the world about this misunderstood neurological condition.
Some notable people who have suffered from narcolepsy include:
- Inventor Thomas Edison.
- Statesman Winston Churchill.
- Comedian Jimmy Kimmel, who discussed his experience of the condition with Esquire magazine.
- Nirvana frontman Kurt Cobain.
What is Narcolepsy?
Narcolepsy was first described in the medical literature in 1880 by the French physician Jean-Baptiste-Edouard Gélineau. The National Organization for Rare Disorders (NORD) describe narcolepsy as follows: “Narcolepsy is a neurological sleep disorder characterized by chronic, excessive attacks of drowsiness during the day, sometimes called excessive daytime sleepiness (EDS).”
Narcolepsy is a neurological (nervous system) disorder that affects the brain’s ability to control sleep and wakefulness.
There are two types of narcolepsy:
- Type 1 narcolepsy, also known as narcolepsy with cataplexy. People with type 1 narcolepsy have excessive daytime sleepiness plus cataplexy and/or low levels of a chemical in the brain called hypocretin. Hypocretins, also known as orexins, are thought to play a significant part in the regulation of sleep and arousal states.
- Type 2 narcolepsy, also known as narcolepsy without cataplexy. People with type 2 narcolepsy have excessive daytime sleepiness but do not have cataplexy and have normal levels of hypocretin.
People who have narcolepsy experience excessive daytime sleepiness and may have uncontrollable episodes of falling asleep during the daytime. These sudden sleep “attacks” may occur during any type of activity and at any time of the day. Contrary to a common misconception, individuals with narcolepsy don’t sleep constantly, although they do struggle with excessive sleepiness throughout the day.
There is also a heightened risk of narcolepsy sufferers falling asleep when they are not supposed to which can put them at risk of dangers. Also, although it may seem paradoxical, they may struggle with falling asleep at night.
Narcolepsy is often confused with insomnia, as individuals who suffer from both disorders may have trouble sleeping at night. However, the two conditions represent opposite ends of the sleep disorder spectrum. Someone can have both narcolepsy and insomnia, as it is possible that a person with narcolepsy may experience insomnia as one of their symptoms.
What is the prevalence of Narcolepsy?
Narcolepsy is fairly rare, affecting about 1 in 2,500 people in the UK, which means that approximately 30,000 people in the UK are narcolepsy sufferers. There appears to be no distinction between men and women suffering from the disorder, both genders seem to be equally affected.
Worldwide figures for narcolepsy show occurrence rates vary among populations, for example 1 in 5,000 people in Israel has narcolepsy, which appears to be low compared with 1 in 600 people in Japan; however, ethnicity is not really a factor as the condition does affect every racial and ethnic group.
Narcolepsy type 1 – that is, narcolepsy with cataplexy – is estimated to have a worldwide prevalence of 25 to 50 per 100,000 people, whereas the prevalence of narcolepsy type 2 – that is, narcolepsy without cataplexy – is uncertain because it is not as well studied and harder to diagnose; however, prevalence has been estimated to be 20 to 34 per 100,000 people.(PubMed).
Narcolepsy typically begins in the teens and early twenties (15–25 years), but occasionally it occurs as early as five years of age or after 40 years of age.
What is Narcolepsy and Cataplexy?
According to Narcolepsy UK, it is thought that about 75% of patients with narcolepsy experience cataplexy. Cataplexy is the term given to sudden muscular weakness triggered by strong emotions such as laughter, anger and surprise.
The loss of muscle tone that occurs may range from a just-perceptible weakening of the facial muscles through to weakness at the knees, to total collapse on the floor. Speech may be slurred, and eyesight impaired, for example double vision and inability to focus; however, hearing and awareness remain undisturbed.
Cataplexy is not always linked to narcolepsy, and approximately 30% of cataplexy episodes are related to other disorders such as:
- Strokes, brain tumours and inflammatory processes of the brain that injure orexin neurons. In rare cases, cataplexy can also be a side effect of medications such as medications for insomnia that block orexin. These can cause cataplexy in rare cases. Fortunately, cataplexy typically disappears after patients stop taking these medications.
- Prader-Willi Syndrome: Prader-Willi syndrome is a genetic condition that begins in childhood, leading to early feeding challenges, delayed growth and development, and an insatiable appetite. In this condition, both excitement and food may cause cataplexy.
- Angelman Syndrome: This genetic disorder affects the nervous system, leading to intellectual disability, speech impairment, and problems with movement and balance. Cataplexy has been reported in many children with this disorder.
What is Narcolepsy caused by?
It is now generally believed that, in most cases at least, narcolepsy is an auto-immune disorder, caused by the destruction of certain cells within the brain by the body’s own immune system. The cause of narcolepsy is often an infection that “tricks” the immune system into destroying the cells that produce hypocretin by mistaking those cells for attacking bacteria or viruses. The infection might be nothing more than a sore throat or flu-like infection.
Following a flu pandemic in 2009, scientists noticed an increase in narcolepsy diagnosis; this may have been caused by the pandemic and the symptoms of the flu, or may have been caused by the use of the flu vaccine Pandemrix.
Research carried out in 2013 found an association between Pandemrix and narcolepsy. The risk is very small, with the chance of developing narcolepsy after having a dose of the vaccine estimated to be around 1 in 55,000; however, Pandemrix is no longer used in the UK for flu vaccination.
Scientists worldwide are currently studying the effects of the COVID-19 pandemic and the association between immune system activation and the development of autoimmune conditions such as narcolepsy.
It is generally not the case that narcolepsy runs in families. There is a particular gene present in quite a large proportion of the population that may play a part in narcolepsy, but it is more a case of lower risk for those people who do not have that gene, rather than higher risk for those who do.
Most narcolepsy sufferers have undetectable or low levels of hypocretin. If the cells that produce it are destroyed, hypocretin levels are reduced and the sleep-wake cycle is not properly controlled. Factors, such as stress, exposure to toxins and infection, may play a role in the reduction of hypocretin levels and therefore contribute to the onset of narcolepsy.
Rarely, narcolepsy results from traumatic injury to parts of the brain that regulate wakefulness and REM sleep or from tumours and other diseases in the same regions.
What is the treatment for Narcolepsy?
Narcolepsy is not curable; it is considered to be a lifelong condition. It is, however, treatable. The aim of treatments is to reduce symptoms, ensure safety, particularly for the sufferer, and to improve quality of life.
Treatment for narcolepsy falls into two categories:
- Behavioural approaches.
Medication – Any medication prescribed will be dependent upon a full medical examination. As there is no cure for narcolepsy, any medication prescribed will be aimed at reducing the effect of the symptoms.
GPs may offer stimulants such as:
These stimulate your central nervous system, which can help keep you awake during the day; they are usually taken in tablet form every morning.
However, there are side effects of stimulants, which include:
- Difficulty sleeping at night (insomnia).
- Stomach aches.
- Weight loss.
Cataplexy, hallucinations, disrupted night-time sleep and sleep paralysis may also be treated with antidepressant medications.
The predominant treatments for narcolepsy are behavioural approaches that involve a change in lifestyle to alleviate the symptoms.
These can include:
- Keeping a regular sleep schedule, which involves going to sleep and rising at the same time each day.
- Stopping exercising around 4–5 hours before bedtime.
- Choosing relaxing activities before bedtime, such as a warm bath.
- Making sure that your bedroom is warm, dark, quiet and comfortable to encourage sleep.
- Using relaxing scents in the bedroom such as peppermint, eucalyptus or lavender.
- Avoiding working or watching TV in bed so you associate your bed with sleep only.
- Avoiding caffeine, alcohol and smoking, particularly before bed.
- Planning naps of around 15–30 minutes every day may help, particularly between 2pm and 4pm and especially before events where you need to be alert.
- Eating meals at regular times.
- Avoiding large meals and alcohol during the day as they can induce sleep.
- Some people living with narcolepsy benefit from avoiding refined carbohydrates.
- Maintaining an active and healthy lifestyle with plenty of physical exercise, fresh air and daylight.
- Breaking up long tasks and planning naps when concentration starts to drop.
- Reducing stressful events that may act as a trigger.
- Avoiding cold and allergy medications that induce drowsiness.
- Talking with family, friends and healthcare professionals about the condition to ease any stresses or fears.
Be aware of situations where you are likely to be at risk of falling asleep or suffer from a cataplexy attack and inform others around you. People with narcolepsy should avoid any activity that could pose a health threat, such as using machinery or driving, until treatment is able to improve their condition.
Narcolepsy and driving
Many people with narcolepsy are able to drive; however, that primarily applies to standard Group 1 vehicle licences valid for cars, motorcycles and mopeds. Because of the greater risks involved it would be unusual for a person with narcolepsy to be issued with a Group 2 larger vehicle licence.
Driving can be dangerous if you have narcolepsy. People with narcolepsy do have a greater risk of accidents, so you must tell DVLA if you have or develop narcolepsy; this covers drivers of all types of vehicles including motorcycles.
The DVLA will send you a medical questionnaire for more information about your narcolepsy and they will carry out the necessary investigations to reach an informed decision on whether to permit you to drive. Their decision may include issuing a fixed-term driving licence for 1, 2 or 3 years, with a review at the end of that period.
If you are applying for your first driving licence in order to learn to drive, it is essential that you inform the DVLA of your condition. They will ask you to complete a medical information form and will decide whether you can have a driving licence based on the information that you provide in the form; they may contact your doctor for more information if they need it. Although you may have to wait to start lessons, you can take the theory test while you wait – your pass result will remain valid for two years.
If you already hold a driving licence and are diagnosed with narcolepsy you must inform the DVLA. Then, unless your doctor advises that your condition is controlled well enough that you meet the medical standards for driving, you must stop driving immediately. If your doctor advises you that you should stop driving, you must surrender your driving licence to the DVLA.
By voluntarily surrendering your driving licence, you will retain the right to apply to have your driving licence re-issued as and when your narcolepsy is sufficiently well controlled that your doctor feels you can safely drive.
However, should the DVLA revoke your driving licence because you failed to surrender it, they may decide not to re-issue your driving licence, you will have to go through an appeal procedure and may also have to retake your driving test to regain your driving licence.
If you continue to drive against your doctor’s advice, under General Medical Council (GMC) rules, your doctor has a responsibility to inform the DVLA of your condition as you are a potential danger to yourself and the general public.
You can be fined up to £1,000 if you don’t tell DVLA about a medical condition that affects your driving and you may be prosecuted if you are involved in an accident as a result.
You should also inform your insurance company if you have or are diagnosed with narcolepsy, as not doing so will invalidate your policy. Under the Equality Act 2010, insurance companies should not refuse insurance or increase the cost of your policy just because you have a history of narcolepsy, as it is classified as a disability.
For anyone considering driving abroad, the rules for driving with narcolepsy vary from country to country. So even if you are permitted to drive in the UK you will need to contact the Embassy of the country you are visiting for further information on whether you will be allowed to dive in that country.
Signs and symptoms of Narcolepsy
Narcolepsy causes the body to transition rapidly between sleeping and waking states. People with narcolepsy can fall asleep quickly and enter REM sleep much faster than those without this disorder. Narcoleptic patients regularly wake up often during the night and spend time in abnormal intermediate states in which they are neither fully asleep nor fully awake.
Narcolepsy symptoms are often called a tetrad, meaning that there are four core symptoms of this condition:
- Excessive daytime sleepiness.
- Sleep paralysis.
Not everyone with type 1 or type 2 narcolepsy experiences the same symptoms. The severity and frequency of symptoms may also vary greatly among individuals.
Signs and symptoms of this narcolepsy tetrad can include:
Excessive daytime sleepiness
This is the main symptom for almost all people with narcolepsy. People with narcolepsy feel sleepy most of the time, and at times that sleep is not normally appropriate. The urge to sleep at these times is severe and irresistible. In some cases, sleep can occur in situations where they are active, for instance when they are driving, talking or eating.
Someone with narcolepsy has no control over the sleepiness that they feel, and they can have sleep attacks in which they fall asleep with no warning. These attacks can occur several times a day, and may last from a few minutes to an hour. When they wake up, a person with narcolepsy usually feels refreshed, but they can soon become sleepy again. The duration of night-time sleep has no effect on excessive daytime sleepiness.
This symptom is the inability to move or speak just before falling asleep or just after waking up. A person remains fully conscious during sleep paralysis, but is unable to speak or move. Episodes of sleep paralysis usually go away after a few seconds to a few minutes. About 25% of people with narcolepsy experience sleep paralysis.
Usually, these delusional experiences are vivid and may be frightening. The hallucinations occur just before falling asleep – known as hypnagogic hallucinations – or just after waking up – known as hypnopompic hallucinations. Hallucinations are mainly visual, but you can also feel that you can hear, taste or smell things.
Examples include seeing a person or animal in the room, feelings of floating or sensations of being touched, or hearing an alarm or voices. Hypnagogic hallucinations, those that occur when a person is falling asleep, affect about one-third of people with narcolepsy.
As we have already seen, this symptom which is experienced by 75% of people with narcolepsy, is a sudden loss of muscle tone or strength brought on by strong emotions, such as laughter, fear, surprise, stress or anger. Attacks can occur any time you are awake. The attacks range from a brief buckling of the knees or slackness in the jaw or drooping of the eyelids to total body paralysis with collapse. Cataplexy usually lasts a few seconds to several minutes. You remain fully conscious during these attacks. The rate of attacks ranges from a few in a lifetime to several per day. Although frightening, there is no damage from these episodes.
Above are the four main signs and symptoms of narcolepsy; others can include:
Disrupted night-time sleep
While doctors have long recognised the classic tetrad of narcolepsy symptoms, recent research suggests that disrupted night-time sleep is also a common occurrence in people with narcolepsy, affecting between 30% and 95% of patients.
This is experienced by some narcolepsy sufferers. Insomnia is a sleep disorder that can make it hard to fall asleep, hard to stay asleep, or cause you to wake up too early and not be able to get back to sleep. Insomnia can sap not only energy levels and mood but also impact health, work performance and quality of life.
This symptom is described as falling asleep for several seconds but continuing to perform routine tasks, such as eating, talking, driving or writing, without any awareness or later memory of ever doing the task. Automatic behaviours can be very dangerous.
For people with narcolepsy the sleepiness can also lead to problems with memory and the ability to concentrate. Some people with narcolepsy experience blurred or double vision. The part of the brain that does not function properly in people with narcolepsy is also believed to play a role in regulating appetite and as a result people who develop narcolepsy often gain weight suddenly.
Other sleep disorders seen in people with narcolepsy can include sleep apnoea, REM sleep behaviour disorders, and periodic limb movement disorder. People with narcolepsy may also face an increased risk of cardiovascular and metabolic conditions such as high blood pressure, high cholesterol, obesity and diabetes. Narcolepsy is also associated with some mental health disorders including attention deficit hyperactivity disorder (ADHD), anxiety, eating disorders, depression and schizophrenia.
It is very common for those with narcolepsy to suffer from depression. Many symptoms of narcolepsy, particularly sleep attacks and cataplexy, can cause great embarrassment and wreak havoc on someone’s ability to live a normal life. These episodes can be frightening, and people may become depressed because of the sudden lack of control. Fear of falling asleep or collapsing suddenly can also lead some people to become reclusive and withdrawn.
Although narcolepsy is a chronic, lifelong condition, symptoms do not typically worsen as a person grows older, so finding strategies to manage and improve the symptoms can help with a person’s quality of life.
Does Narcolepsy impact sleep?
Most people sleep for around seven or eight hours each night and it usually takes about 10 minutes to fall asleep. Each sleep cycle comprises two main stages: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.
In a normal sleep cycle, REM sleep occurs at the end of each cycle. A person enters REM sleep after about 60 to 90 minutes and it lasts only a few minutes. Dreams occur during REM sleep but they are usually forgotten, and the brain keeps muscles limp during this sleep stage. This relaxed muscle tone and “paralysis” prevents people from acting out their dreams; this is a defence against self-injury.
Whereas if you have narcolepsy, you usually only have broken sleep, and timing it is difficult – you will typically take less than 5 minutes to fall asleep. People with narcolepsy frequently enter REM sleep rapidly, sometimes immediately, but usually within 15 minutes of falling asleep. Also, the muscle weakness or dream activity of REM sleep can occur during wakefulness or be absent during sleep.
Most people are troubled by waking up frequently during the night and symptoms often get worse in middle age, only improving some years later.
What is secondary Narcolepsy?
A condition known as secondary narcolepsy, the rarest type of narcolepsy, can result from an injury to the hypothalamus, a region deep in the brain that helps regulate sleep.
In addition to experiencing the typical symptoms of narcolepsy such as fragmented sleep at night, individuals may also have severe neurological problems and sleep for long periods of time, that is for more than 10 hours each time. Secondary narcolepsy can also be caused by a brain tumour, multiple sclerosis or brain inflammation called encephalitis.
Narcolepsy is difficult to diagnose. People with mild narcolepsy may never know they have it, while severe cases are easily confused with other conditions such as epilepsy or sleep apnoea.
Anyone suspecting that they have narcolepsy should talk to their GP who can arrange some tests that can lead to a formal diagnosis. Two types of test are normally used – each involves monitoring brain activity, breathing rate and heart activity.
Polysomnogram – This overnight test detects abnormal sleep activity. It allows narcolepsy to be differentiated from other conditions.
Multiple sleep latency test – This day test measures the time taken to fall asleep when catnapping and detects REM sleep and how quickly this occurs.
Because low levels of hypocretin are associated with narcolepsy, measuring the level of hypocretin in your cerebrospinal fluid, which surrounds the brain and spinal cord, can also be useful in diagnosing narcolepsy.
You may be asked by your doctor to wear a wrist motion sensor for a few weeks or to keep a sleep diary. This involves keeping notes about how easy it is for you to fall asleep and stay asleep, how many hours of sleep you get each night and how awake you feel during the day.
What support is available?
Narcolepsy can have a significant impact on a person’s quality of life. Frustration, low mood and even depression can occur in patients suffering from narcolepsy. The risks can sometimes be minimised by talking openly about your condition to your GP or friends and family. This helps the isolation many patients feel.
Support groups also provide individuals with a network of social contacts who can offer practical help and emotional support.
Having narcolepsy can have a significant impact on your quality of life, and may affect your financial situation. Your ability to earn an income may go down because of the effects of your health problems, so it is important to find out if there are any benefits you can claim. Even if you are still working there may be other benefits you are entitled to. The official UK Government website includes numerous resources that may be helpful including rights to benefits and disability allowances.
The Equality Act 2010 requires employers to provide reasonable adjustments for all employees with disabilities. Adults with narcolepsy can often negotiate with employers to modify their work schedules so they can take naps when necessary and perform their most demanding tasks when they are most alert.
You should inform an employer about your narcolepsy diagnosis in order that they can carry out necessary risk assessments to protect you, your co-workers and any members of the public if applicable.
Similarly, parents and/or carers of children and young people with narcolepsy may be able to work with their school to accommodate their special needs, for example, taking any medications during the school day, modifying class schedules to fit in a nap, and other strategies for safeguarding. It is important to keep teachers and school management informed of a diagnosis of narcolepsy. With appropriate allowances made for their sleep disorder, most students can achieve to their full potential.
Narcolepsy, although an incredibly rare condition, can have an effect on almost all aspects of a person’s daily life including education, employment, their ability to drive or use machinery, and also on their relationships and emotional health. Having narcolepsy may present difficulties but certainly should not prevent someone from enjoying life. With support from the medical profession, friends and family and with reasonable adjustments to work and life style, narcolepsy can be managed.