How doctors diagnose narcolepsy

Narcolepsy with and without Cataplexy 

causes

In people with narcolepsy, a small area of ​​the brain does not function normally. The irreversible destruction of certain cells results in a deficiency in a certain hormone, orexin, which stabilizes the waking state (2-4). Hereditary autoimmune processes, in which the own immune defense is directed against the corresponding brain regions, are considered to be the cause. The risk of disease in genetically susceptible people can be increased by infections or the swine flu vaccination. (5)

Changed sleep phases

Sleep in healthy people is divided into approx. 90-minute sleep cycles, with each cycle containing a so-called Rapid Eye Movement (REM) phase and non-REM phases. The REM phase is characterized by rapid eye movement with the eyelids closed. Most dreams take place in this phase. The non-REM phase precedes the REM phase and is divided into light and deep sleep (6).

In contrast to healthy people, narcoleptics start the REM phase immediately after falling asleep; all non-REM phases are not passed through (7).

Symptoms

The classic symptoms of narcolepsy are excessive daytime sleepiness, night sleep disorder, hallucinations, sleep paralysis, and cataplexy. They can be very different from patient to patient, and individual symptoms (e.g. cataplexy) can also be completely absent (8).

Excessive daytime sleepiness

Daytime sleepiness is the most prominent symptom of narcolepsy and is often described by patients as insurmountable. Narcoleptics feel tired and lacking energy during the day and can suddenly fall asleep unintentionally. These naps are often very short, after which patients feel relaxed and more alert than before. (7,9)

As a consequence of increased daytime sleepiness, so-called “automatic action” can occur, in which actions are carried out “half asleep”, so to speak, and can be faulty or pointless (7).

Disturbed night sleep

A little-known but common symptom of narcolepsy is disturbed sleep at night, characterized by frequent waking up (9).

Sleep-related hallucinations

Narcolepsy patients often experience intense hallucinations when falling asleep or waking up. These can be visual, acoustic or tactile and are often experienced as very realistic. The hallucinations are often perceived as threatening or unpleasant. (7)

Sleep paralysis

The sleep paralysis, which lasts only seconds to a few minutes, is characterized by a complete inability to move. While it occurs in healthy people during sleep to prevent movement while dreaming, in people with narcolepsy it occurs more frequently when falling asleep or waking up and is therefore experienced consciously and perceived as frightening. (7)

Cataplexy

A short-lasting muscle failure of varying degrees is called cataplexy. In mild cases, for example, only the facial muscles slacken; in severe cases, a patient can slump and fall to the ground. Cataplexies can be triggered by emotions such as laughter, anger or surprise and usually only last a few seconds. (10)

  1. Longstreth WT, Koepsell TD, Ton TG, Hendrickson AF, van Belle G. The epidemiology of narcolepsy. Sleep. 2007; 30 (1): 13-2
  2. Nishino S, Ripley B, Overeem S, Lammers GJ, Mignot E. Hypocretin (orexin) deficiency in human narcolepsy. Lancet. 2000; 355 (9197): 39-40
  3. Thannickal TC, Nienhuis R, Siegel JM. Localized loss of hypocretin (orexin) cells in narcolepsy without cataplexy. Sleep. 2009; 32 (8): 993-8
  4. Thannickal TC, Moore RY, Nienhuis R, Ramanathan L, Gulyani S, Aldrich M, et al. Reduced number of hypocretin neurons in human narcolepsy. Neuron. 2000; 27 (3): 469-74
  5. Bonvalet M, Ollila HM, Ambati A, Mignot E. Autoimmunity in narcolepsy. Curr Opin Pulm Med. 2017; 23 (6): 522-9
  6. Law A, Kales A. Los Angeles: University of California, Brain Information Service / Brain Research Institute. 1968
  7. Dauvilliers Y, Billiard M, Montplaisir J. Clinical aspects and pathophysiology of narcolepsy. Clin Neurophysiol. 2003; 114 (11): 2000-17
  8. German Society for Neurology - Narcolepsy guidelines. 2012: https: //www.dgn.org/images/red_leitlinien/LL_2012/pdf/030-056l_S1_Narkolepsie__verlaengert.pdf
  9. Roth T, Dauvilliers Y, Mignot E, Montplaisir J, Paul J, Swick T, et al. Disrupted nighttime sleep in narcolepsy. J Clin Sleep Med. 2013; 9 (9): 955-65.
  10. Dauvilliers Y, Arnulf I, Mignot E. Narcolepsy with cataplexy. Lancet. 2007; 369 (9560): 499-511.

Narcolepsy during pregnancy and breastfeeding

Because the symptoms of narcolepsy often first appear in young adulthood, information about managing narcolepsy during pregnancy is relevant. To date, only a few studies have examined the influence of narcolepsy on pregnancy.

Medication during pregnancy and breastfeeding

Narcolepsy patients who want to have children or who have already found out that they are pregnant should definitely contact their doctor. With regard to the medication, it is important that the doctor and the patient carry out a precise risk-benefit assessment in order to decide which medication should be taken as usual, reduced in dose or discontinued entirely.

The majority of doctors recommend that women who want to have children, pregnant women, and breastfeeding women discontinue use of drugs used to treat narcolepsy symptoms (1).

The drugs used to treat narcolepsy cross the placenta - this means that the unborn child is also treated, so to speak. The active ingredient of common narcolepsy drugs is also passed on to the newborn in breast milk. (1)

Possible complications during pregnancy

In rare cases, cataplexy can occur during childbirth (2), which can affect delivery. The data from a recently published study show that gestational diabetes appears to be more common in patients with narcolepsy with cataplexy than in healthy women, and the birth weight of newborns also appears to be higher. In addition, narcolepsy patients had to give birth more often (4).

Caring for the newborn

Many narcolepsy patients report the effects of the disease on newborn care. In most patients, care is made more difficult by daytime sleepiness or involuntary falling asleep while breastfeeding or feeding (2).

1. Thorpy M, Zhao CG, Dauvilliers Y. Management of narcolepsy during pregnancy. Sleep Med. 2013; 14 (4): 367-76.
2. Maurovich-Horvat E, Kemlink D, Högl B, Frauscher B, Ehrmann L, Geisler P, et al. Narcolepsy and pregnancy: a retrospective European evaluation of 249 pregnancies. J Sleep Res. 2013; 22 (5): 496-512.
3. Maurovich-Horvat E, Tormášiová M, Slonková J, Kemlink D, Maurovich-Horvat L, Nevšímalová S, et al. Assessment of pregnancy outcomes in Czech and Slovak women with narcolepsy. Med Sci Monit. 2010; 16 (12): SR35-40.
4. Calvo-Ferrandiz E, Peraita-Adrados R. Narcolepsy with cataplexy and pregnancy: a case-control study. J Sleep Res. 2018; 27 (2): 268-72.

Narcolepsy in Children

Narcolepsy can appear for the first time at almost any age.

It occurs before the age of 10 in around 20% of all narcolepsy patients (1).

Especially in childhood, the symptoms of narcolepsy can be misinterpreted, which can lead to increased suffering.

Excessive daytime sleepiness as the main symptom can often make a quick diagnosis difficult, as it can often be confused with the normal need for sleep in children (2). Because children tend to compensate for sleepiness with hyperactivity, hyperkinetic syndrome is often diagnosed. (1, 3)

Childhood narcolepsy can also be confused with laziness, defiant behavior, epilepsy, other neurological or medical diseases, or intellectual disabilities (2, 3). Falls as a result of cataplexy can be misinterpreted as clumsiness (2).

Symptoms of narcolepsy can cause anxiety, shame, helplessness, and depression in children. The lack of understanding and prejudice by the social environment can lead to social withdrawal (2).

Excessive daytime sleepiness can affect concentration, memory, and other cognitive performance, and result in poor academic performance (2).

Behavioral disorders and depression can also follow, which can contribute to a reduced quality of life (3).

A rapid diagnosis is essential to prevent long-term effects of narcolepsy on the psyche of children.

1. Mayer G, Kotterba S. 2001. p. 249-54.
2. Stores G. The protean manifestations of childhood narcolepsy and their misinterpretation. Dev Med Child Neurol. 2006; 48 (4): 307-10.
3. Stores G, Montgomery P, Wiggs L. The psychosocial problems of children with narcolepsy and those with excessive daytime sleepiness of uncertain origin. Pediatrics. 2006; 118 (4): e1116-23.

Diagnosis and neurological sleep laboratories in Austria

The Austrian, German and Swiss Society for Neurology sets standards for the diagnosis of narcolepsy in its guidelines (1).

Initially, it is recommended to take a targeted medical history of the core symptoms of excessive daytime sleepiness and cataplexy. Since narcolepsy can occur in families, a family history should also be taken. (1)

The patient should document his sleep behavior using various sleep questionnaires and sleep diaries (1). The Epworth Sleepiness Score (ESS), for example, records daytime sleepiness and is intended to reflect the probability of falling asleep under certain everyday conditions (e.g. while watching TV) (2).

In addition, a polysomnography - i.e. the monitoring of different body functions during sleep - and a so-called Multiple Sleep Latency Test (MSLT) should be carried out. Particular attention should be paid to phases with a shorter time to fall asleep and premature REM sleep. A typical finding in narcolepsy patients is also interrupted sleep and a shortened time to fall asleep during the day. (1)

In individual cases, further examinations such as determining the orexin level in the CSF or imaging procedures may be necessary. (1)

Because narcolepsy is a neurological sleep disorder, a diagnosis should be made in a neurological sleep laboratory, such as:


The complete, updated list of neurological sleep laboratories in Austria can be found here:

http://www.schlafmedizin.at/schlaflabore.html

everyday life

The quality of life of people with narcolepsy can suffer greatly as a result of the condition. Symptoms can make patients feel neglected or excluded.

Narcolepsy in Society

For the environment, the symptoms - especially daytime sleepiness and cataplexies - are difficult to classify and are incorrectly interpreted as laziness, disinterest, alcoholism or even drug addiction. Narcolepsy sufferers suffer greatly from this stigmatization, which can lead to avoidance of emotional situations (to avoid cataplexy) and withdrawal from social life. Sudden falling asleep and cataplexy in public are perceived by the patient as "embarrassing" and are prevented as much as possible - among other things by not participating in social life.

Narcolepsy and Relationship / Family

But problems can also arise in partnerships and families. By trying to avoid emotions, narcolepsy patients often appear distant and aloof. By dealing openly with the disease, people can understand these situations and their own self-confidence can be strengthened. This enables those affected to actively participate in life again.

Both symptoms and drug treatment of narcolepsy can have a negative impact on sexuality and impair a relationship. Problems of this kind should therefore be discussed with the partner and the treating doctor.

Narcolepsy in school and work life

Narcolepsy can occur even at school age. Falling asleep during class is often misinterpreted, and so the student suffers from misunderstanding. Undetected narcolepsy can also adversely affect academic performance, leading to poor assessments that are inappropriate for the talent.

Since daytime sleepiness increases the risk of accidents, narcolepsy also plays an important role in choosing a career. Some jobs can no longer be carried out after narcolepsy has occurred. Professions with motor vehicles or the operation of dangerous machines are particularly unsuitable. Professions that have to be carried out at height, such as roofers, are just as unsuitable. Monotonous work tends to lead to spontaneous nodding off and irregular working hours can worsen the clinical picture.

Narcolepsy and Travel

There are a few things to keep in mind for a successful trip for people with narcolepsy. Traveling with someone you trust makes things easier. If this is not possible, support is available at many train stations and airports, for example in the form of escorts or wheelchairs. In this way, excitement and exertion - the triggers of cataplexy - can be avoided. In order to enable quick and correct treatment in an emergency, it is advisable to carry a patient ID card with you. Since many drugs used to treat the symptoms of narcolepsy fall under the Addictive Substances Act, they may not be easily transported. For trips within the Schengen area and with a duration of less than 30 days, a certificate issued by the treating doctor is sufficient, which must be certified by a public health officer (1). When traveling to other countries, the patient must clarify the legal situation in the destination country before starting the journey and make appropriate preparations.

BMGF travel information: Taking medication abroad

Epworth Sleepiness Scale (ESS)

Information about ESS can be found in English at https://epworthsleepinessscale.com/

Please find below a PDF download "Questionnaire on daytime sleepiness"