Have you been sleepy for a long time, even though you have slept the required 8 hours? You may be physically or emotionally tired. However, if you feel this for a long time, it would be better to check your health and find out if you have narcolepsy.
What Is Narcolepsy?
Narcolepsy is one of the so-called rare diseases. In its case, the brain produces too little of the hormone orexin, which usually helps you stay awake. Therefore, people with narcolepsy often feel so sleepy during the day, as if they had not slept for 36 hours.
Another symptom – cataplexy – is a sudden short-term loss of muscle tone (muscle weakness), mostly because of positive emotions.
Initially, it can only manifest itself in the face, for example, as drooping eyelids, mouth open, slurred speech.
Young people admit that others have sometimes said that they look drunk. Later, during a cataplexy attack, it may be difficult to hold objects or the person may even get injured.
Narcolepsy is also characterized by paralysis of sleep (when a person wakes up for some time cannot move) and hallucinations when waking up or falling asleep.
Symptoms most often appear in early adolescence and can make you feel awkward because they affect your daily life, social abilities, and behavior at school.
It is important to understand that narcolepsy does not affect life expectancy, thinking ability or physical ability.
If you recognize any of the symptoms in your daily life, it is necessary to consult a sleep specialist. Narcolepsy is diagnosed by a sleep examination (polysomnography and a multiple sleep latency test).
The examination takes place by observing different phases of sleep at night and during the day.
At the very beginning, the symptoms are very general – great fatigue, drowsiness, with which many simply come to terms.
Other symptoms are often overlooked by people (eg sleep paralysis, hallucinations); other more specific symptoms join later and gradually (cataplexy), so people often suffer from drowsiness for several years without knowing what is bothering them.
The disease is still too little recognized in the world. It is estimated that about 5 to 16 per 10,000 population have narcolepsy.
At present, science has not yet discovered how to cure narcolepsy, but medication and a change in daily routine can significantly reduce the symptoms.
The first meeting for patients with severe sleep disorders took place online and was attended by both adolescents and their parents to gain support and improve their quality of life by discussing experiences related to rare diseases.
It is extremely important for patients to know that they are not alone in their problems and that someone else understands what they are going through.
Young people shared experiences about the importance of making peers more aware of narcolepsy, such as schoolmates and teachers.
Narcolepsy is a chronic neurological disease characterized by irresistible daytime sleepiness that significantly affects quality of life and daily functioning.
Although narcolepsy is relatively rare, it is one of the most common causes of increased drowsiness after obstructive sleep apnea.
The incidence is estimated at ~ 3-16 per 10,000 (equally common for women and men). Symptoms usually develop after puberty (mostly between the ages of 15 and 30), although some studies report that 15% of adults develop symptoms before the age of ten.
We divide primary narcolepsy into two types:
- type I (formerly narcolepsy with cataplexy)
- type II (formerly narcolepsy without cataplexy).
In children, 20-33% of narcolepsy cases are secondary.
Compared to primary narcolepsy, symptoms usually appear earlier, at an average age of 6, and cataplexy is the most pronounced symptom.
Pathophysiology, Etiology and Risk Factors
Most symptoms of type I narcolepsy are due to decreased levels of the neuropeptides orexin A and orexin B.
They take part in the maintenance of wakefulness, and because of the lack of orexin, both REM (rapid eye movement) and NREM (non-rapid eye movement) sleep fragments break into wakefulness.
In type II narcolepsy, orexin levels are usually normal; I think this type of narcolepsy to be because of less loss of orexin neurons, altered state of orexin receptors, or a completely different mechanism.
Approximately 24% of patients with type II narcolepsy have decreased orexin A levels, and approximately half of these patients subsequently develop cataplexy, showing progressive disease (in which case narcolepsy we reclassify as type I).
There are several theories that explain the etiology of primary narcolepsy:
- Genetic factors
Although narcolepsy usually develops sporadically, there is a genetic predisposition (HLA DQ antigen). The sensitivity of genetic testing is low, as 12-38% of the general population are positive for these antigens;
- Infections and autoimmune processes
Some researchers suggest that autoimmune processes may damage orexin-producing neurons. 17% of narcolepsy patients have been reported to have another autoimmune disease (multiple sclerosis, psoriasis, Crohn’s disease, etc.).
We have observed it that the most common symptoms begin in the spring, possibly after an infection.
One trigger is streptococcal pharyngitis, as the titres of antistreptolysin O and anti-DNAse B are elevated (especially during the first year after the onset of narcolepsy symptoms).
In some European countries, there has been an increase in narcolepsy since they gave the Pandemrix flu vaccine in 2009. This vaccine was not used in the United States.
In 2014, a study by the Centers for Disease Control and Prevention compared a 2009 vaccine containing the H1N1 strain used in the United States with a vaccine used in 2010; we associated none of these vaccines with an increased risk of developing narcolepsy.
The 2018 study, which involved ten study centers, compared vaccines containing the same adjuvant as the Pandemrix vaccine.
They have not shown these vaccines to be associated with narcolepsy, except in Sweden, which was one of the original reporting countries.
Secondary narcolepsy is caused by structural brain damage, metabolic and genetic diseases, and vascular and infectious hypothalamic strokes.
Narcolepsy is characterized by classical tetrad: daytime somnolence, cataplexy, hypnotic and hypnopompic hallucinations, and sleep paralysis.
Symptoms (in terms of prevalence, severity) do not occur immediately, they progress over months / years and persist throughout life. Full tetrad is very rare at the onset of the disease and is also seen in adults in ⅓ — ½ patients.
The first symptom is usually severe drowsiness. Cataplexy, the most specific symptom of narcolepsy, can begin in a few weeks or even decades.
For this reason, we should consider narcolepsy a diagnosis, even if the patient are suffering from only daytime.
Increased Daytime Sleepiness
It is mandatory and the most common first symptom of narcolepsy (except for secondary narcolepsy, when cataplexy may be the first symptom).
In narcolepsy patients, the Epworth Drowsiness Scale score is usually above 15 points. For younger children, dieting is still considered the norm, so increased daytime sleepiness may not be noticed so quickly.
The urge to fall asleep that is difficult to overcome is usually characterized by calm and “boring” activities, such as driving a car, sitting in a meeting or lecturing, but the patient can also fall asleep during a conversation or while eating or even walking.
Drowsiness during the day does not decrease with sufficient or increased amount of sleep at night, but the symptoms of a small diet (30-40 minutes) temporarily improve, so one principle of narcolepsy treatment – planned diets at the same time each day.
Patients with narcolepsy are also characterized by ‘sleep attacks’ – temporary episodes of uncontrollable falling asleep. In adults, they usually last a few seconds.
The patient himself rarely notices this “micro-sleep”, but from the outside the person is thinking and looking into the distance.
In children, sleep attacks can be much longer – up to 90 minutes. If it awakens the child, sleep intoxication may follow – confusion, mild irritability and sometimes even aggressive behavior.
In young children, drowsiness is paradoxically diagnosed as a syndrome of attention deficit hyperactivity disorder, because in order to ward off drowsiness and fatigue, children try to encourage themselves by moving more.
Sudden temporary loss of muscle tone, mostly because of positive emotions. In rare cases, negative emotions can also cause cataplexy.
Although this is a specific symptom of narcolepsy, we rarely see it in patients with Prader-Willi or Einelmann syndrome, Niemann-Pick Type C disease, and Norwegian disease.
Cataplexy affects 60-100% of adults and 60-80% of children with narcolepsy and usually develops within a year of the onset of increased somnolence. A cataplexy episode can last from a second to several minutes.
Unlike adults, whose cataplexy often manifests throughout the body, in children it usually begins in the face (cataplectic facies): sloping eyelids, mouth open, tongue out.
In milder cases, parents notice that the child’s face “shakes”, but in more severe cases, cataplexy is observed almost continuously, so the child looks sleepy, with a dull gaze.
Later, muscle weakness progresses to the fibroids: torso → arms → legs → full body.
Transient episodes of cataplexy may be mistaken for epileptic seizures, awkwardness, or psycho-emotional events (pseudo-seizures or conversion (dissociative) disorders).
The difficulty in diagnosing cataplexy is because the episodes may be sporadic at first, and in children the symptoms may not be pronounced at first.
Some children may be ashamed to talk about their symptoms, and peers sometimes provoke it because it seems funny (“looks drunk”), so it is very important to ask targeted questions about cataplexy several times.
A typical but not specific symptom of narcolepsy; ~ 20% of the population has had an episode at least once in their lives. It is a condition experienced in the moment between sleep and waking up.
The person is awake but unable to move because the atony characteristic of the REM sleep phase is still present.
In adults, sleep paralysis is often accompanied by a feeling of suffocation (“someone sitting on their chest or strangling”), when in fact the respiratory muscles are not affected.
Since it is also accompanied by hallucinations, the experience can be quite intimidating. Younger children may not yet understand sleep paralysis, so a history may be difficult to collect.
Episodes can last from a few seconds to a few minutes and are self-limiting. It is important to tell the patient, especially if these episodes are related to fear.
Sleep paralysis can be stopped by talking to a person soothing and gently touching / shaking.
Older children or adults who experience sleep paralysis may stop it more quickly by focusing on a part of the body (such as the toe) and trying to move it.
Hallucinations are not a specific symptom of narcolepsy (39-50% of patients) and also occur in the general population.
They may be asleep (hypnotic) or when awake (hypnopompic).
In adults, hallucinations are often frightening and realistic, and can be combined with sleep paralysis. Children see more simple shapes (colored circles, human or animal shapes).
Narcolepsy-related hallucinations can be confused with nocturnal fears, nightmares, panic attacks, and adolescents with schizophrenia (when verbal auditory hallucinations predominate, which may or may not be related to sleep).
In patients with narcolepsy, hallucinations are multisensory and associated with falling asleep / waking.
Disturbed / Dragmented Night Sleep
Often, up to 90% of adult patients. Children / parents themselves rarely complain about it themselves, but when asked targeted questions, 89% admit that they sleep poorly. Poor quality sleep further aggravates daytime sleepiness.
More common in kids. Parents complain that the child is grumpy and in conflict for 15-30 minutes after waking up.
Ongoing continuation during a sleep attack, such as writing. Man himself has no memory of it. The frequency increases with fatigue and monotonous workouts.
Automatic behavior can take up to 30 minutes; a person can speak some words or write a full page with meaningless text.
There is also a case where a 4.5-year-old girl attacks her brother with a knife without realizing it. Automatic behaviors are sometimes diagnosed as focal seizures with loss of consciousness.
Characteristic of children and adolescents with narcolepsy. Weight gain usually begins with other symptoms.
This can be associated with poor eating habits (overeating, eating at night) and reduced physical activity because of drowsiness, although children who consume fewer calories and exercise often are also overweight.
Being overweight negatively affects a child’s self-esteem, mood, general health and is a significant risk factor for sleep-disordered sleep, which can further increase daytime sleepiness.
Mental Health Disorders and Personality Changes
It should be borne in mind that younger children find it difficult to understand and explain their feelings, so there is a risk that the symptoms typical of narcolepsy may be interpreted differently.
We could suspect Young people of using addictive substances because of drowsiness or cataplexy.
Worse Quality of Life
Narcolepsy has a significant effect on the quality of life (general well-being, social functions, leisure time), especially in adolescents.
Narcolepsy (especially late diagnosis and without appropriate treatment) carries the risk of lower academic achievement.
Although narcolepsy is not associated with intellectual disabilities, children cannot maintain quality attention because of somnolence and other related disorders. We often describe these children as lazy, careless, or “misbehaving”.
Other Sleep Related Diseases
Patients with narcolepsy are at increased risk of developing obstructive sleep apnea, mostly due to weight gain. Narcolepsy has a higher risk / incidence of Restless Legs Syndrome, parasomnia, REM sleep disorders.
Poorly controlled symptoms have a major impact on the daily routine, such as the patient’s inability to stay awake on public transport and passing a stop.
Patients with narcolepsy have an increased risk of injury, for example, in a study, children with narcolepsy were more likely to be ‘hit’ by a virtual car at a pedestrian crossing. This is because of altered decision-making capacity and ‘careless blindness’.
In order to get a driving license and to renew a medical certificate, we must list all illnesses which may affect driving.
Patients with narcolepsy with well-controlled symptoms may drive, but sometimes the effectiveness of treatment will need to be demonstrated by a wake test.
All patients with chronic somnolence should also be evaluated for other typical symptoms of narcolepsy during the day.
Some questions that could help make a diagnosis:
- “Do you feel sleepy most of the day? Are you sleeping?” → shows drowsiness during the day, but the reasons may be different.
- “Do you see dreams during the day?” → An affirmative answer shows a shorter REM sleep latency, which is characteristic of narcolepsy.
- “Do you sometimes feel as if your arms / legs are weak when laughing? Is something falling out of your hands? Does the face tend to “slip”? “→ cataplexy.
- “Do you ever fall asleep or wake up to see or hear things that aren’t there at all?” → hallucinations.
- “Can’t you move when you wake up?” → sleep paralysis.
It is also important to test other sleep-related illnesses that often accompany narcolepsy and may exacerbate somnolence:
- obstructive sleep apnea – snoring, shortness of breath, restless sleep, drowsiness during the day (on the contrary, hyperactivity in younger children);
- restless legs syndrome – discomfort in the extremities (especially in the legs), which increases during rest and is reduced by movement.
Various scales help to assess drowsiness, such as the Epworth Drowsiness Scale (adult and children’s version) and the Children’s Day Drowsiness Scale.
The Epworth Sleepiness Scale is widely used in sleep medicine; it assesses the possibility of falling asleep or falling asleep in different situations. At least 11 points show increased daytime sleepiness, but narcolepsy patients often have at least 15 points.
Helps to understand the patient’s circadian rhythm.
It is important to assess the amount of sleep (sufficient / too little / too much), bedtime (regular / irregular, late / early / acceptable), waking time (regular / irregular, early / late / acceptable), diet, night sleep (yes / no awakening).
Polysomnography (PSG) and Multiple Sleep Latency Test (MSLT)
Needed to confirm the diagnosis (diagnostic criteria).
PSG is a diagnostic method that uses various sensors to assess several body functions during sleep throughout the night (sleep structure, breathing, heart rate, gas exchange and leg movements).
During PSG, sleep disturbances (obstructive sleep apnea) and we can also assess intermittent limb disturbances, which can also lead to increased daytime sleepiness. Sleep fragmentation and short REM sleep latency may show narcolepsy.
The next day, we perform an MSLT: while maintaining all PSG sensors; we give the patient 4 or 5 options for a short (20 minute) diet at one and a half-hour intervals.
In this way, we assess it whether the patient falls asleep during the diet and whether REM sleep occurs (normally the REM sleep latency is 90-120 minutes, but in patients with narcolepsy it may be a few minutes).
Cerebrospinal Fluid Levels of Orexin / Hypocretin
In type I narcolepsy, it is very low or undetectable. This study has a high specificity and sensitivity for narcolepsy with cataplexy.
Decreased orexin / hypocretin levels can be used as one of the diagnostic criteria. Although not widely available, we can use it in cases where PSG and MSLT are difficult to interpret (eg for young children) or questionable.
Detection of HLA
Not required for diagnosis, but could be useful in case of doubt. Although most narcolepsy patients are HLA positive (75-90%), we should note it we can also find these alleles in 25% of the general population.
Imaging (Magnetic Resonance Imaging)
There is no routine examination for patients with narcolepsy. Use in case of rapid onset of daytime sleepiness, in the presence of any other neurological symptoms or altered neurological findings, or in the event of a recent head injury.
When the patient is in a sleep-promoting environment, the ability to fall asleep is determined using the same sensors as PSG and MSLT.
This test is more commonly used to determine the effectiveness and alertness of treatment for obtaining a driving license or for work-related activities where the ability to stay awake is important.
Narcolepsy with cataplexy can mimic several other diseases and symptoms. Chronic daytime drowsiness is a non-specific symptom various diseases and conditions can cause that.
We present some differential diagnoses of chronic somnolence in the table. Automatic behaviors are sometimes diagnosed as focal seizures with loss of consciousness.
If narcolepsy is suspected, we should refer the patient to a sleep specialist or neurologist who specializes in the diagnosis and treatment of sleep disorders.
Further therapy is under the supervision of these specialists. There is currently no etiological therapy, so the emphasis is on adequate symptom control.
Intravenous orexin analogues developed to date have not been effective, possibly because of their inability to cross the blood-brain barrier. The possibility of administering these analogues intranasally is being investigated.
We base comprehensive care for narcolepsy patients on both non-drug and drug therapy.
Educating the Patient, Family and Others
Narcolepsy has a major impact on the overall quality of life, and the symptoms can be confusing for the patient and others, and for doctors.
The patient could be mistaken for lazy, unmotivated or intoxicated. It is important to educate not only family members but also teachers, colleagues, etc.
They send An information letter to the school from the Epilepsy and Sleep Medicine Center so that the school nurse and teachers have a plan and knowledge of what narcolepsy is and how to deal with it.
Healthy Lifestyle Habits
Important for everyone, but for patients with narcolepsy they are especially important for excellent symptom control:
- Regular Daily Doutine: going to bed and getting up at the same time on weekdays and holidays; adequate sleep,
- Daily Dosing: we recommend it that patients with narcolepsy schedule 1-2 short daily dosing (15-35-45 minutes) daily. Arrange with the teacher / supervisor at the educational establishment or work a room to lie down without hindrance,
- Physical Activity: Patients find that regular physical activity helps to control drowsiness and reduces depressive symptoms and anxiety. We must take care not to injure yourself in sports (because of cataplexy). Some sports (such as swimming) may require supervision.
Prevention and Treatment of Other Sleep-Related Diseases
Weight gain of unclear etiology associated with narcolepsy is a risk factor for obstructive sleep apnea, so it is important to normalize body weight by eating a balanced diet and engaging in appropriate physical activity.
We should also consider other treatment options for respiratory distress (eg adenotonsilotomy, intranasal corticosteroids, sleep ventilation). With Restless Legs Syndrome, the use of iron supplements sometimes helps.
Patients acknowledge that psychotherapy reduces the frequency of symptoms, cognitive-behavioral therapy and various activities (eg writing, painting, regular sports).
Caution should be exercised in patients with narcolepsy.
The goal is mostly to reduce drowsiness and improve daily life. Most times, successfully controlling drowsiness also reduces other symptoms, but we may need medication to reduce the symptoms associated with REM sleep.
In adults, the first-line drug for controlling somnolence is the stimulant modafinil. The other medicines used are dextroamphetamine, methylphenidate, dexmethylphenidate, lisdexamphetamine, solriamphetol, armodafinil and sodium oxybate.
Antidepressants (AD)–SNAIs (venlafaxine), SSRIs (fluoxetine), tricyclic ADs (clomipramine, protriptyline) are used to reduce cataplexy.
The histamine H3 receptor antagonist / inverse agonist pitolysant is used to reduce somnolence and cataplexy in adults, but there is insufficient information on its use in children.
There are currently few studies on long-term treatment in children, so we base the recommendations on studies in adult groups.
We usually start drowsiness reduction with methylphenidate; If symptom control is inadequate, modafinil or sodium oxybate may be changed or added.
In milder cases of cataplexy, medication could be avoided.