Narcolepsy
What is Narcolepsy?
Narcolepsy is a long-term condition whereby your brain’s ability to control your own sleep-wake cycles is reduced, causing excessive sleepiness during the day, falling asleep suddenly at inappropriate times, and uneven sleep throughout the night, along with other symptoms.
Narcolepsy is an extremely rare condition, affecting roughly 1 in 2000 people, though many cases do go undiagnosed [1]. It affects both males and females equally, and symptoms often begin during the adolescent years. Symptoms are commonly confused with other conditions, and thus it can often take a person many years before they are correctly diagnosed with narcolepsy.
Narcolepsy can be categorised into two main types. Type 1 is narcolepsy with cataplexy and Type 2 is narcolepsy without cataplexy. Patients who experience cataplexy have sudden extreme muscle weakness, triggered by strong emotions.
How will having Narcolepsy affect me?
Narcolepsy can greatly affect your ability to function on a day-to-day basis. This is because if you have narcolepsy, you might unknowingly and unwillingly fall asleep at inappropriate times, like driving, talking or eating. It can affect your social activities, work ethic and academics, and also how people view you every day.
So, although narcolepsy does not cause any serious or long-term health issues, it can be really hard to cope with every day and might cause major emotional distress.
What does having Narcolepsy feel like?
Narcolepsy causes excessive daytime sleepiness (EDS), or the inability to stay awake during daytime hours and feeling persistent sleepiness and lack of energy, regardless of the amount of sleep you might have gotten the previous night.
People with Type 1 narcolepsy experience cataplexy, which is brief but sudden muscle weakness that can cause some physical changes such as slurred speech or small facial tics. It is triggered by strong emotions and may only appear weeks or even years after EDS is first experienced.
Narcolepsy also causes hallucinations and sleep paralysis. You might experience strong and dream-like hallucinations just as you are falling asleep or waking up. The boundary between sleeping and being awake can feel blurred. You might also experience a temporary inability to move or speak when waking up or falling asleep.
What are the causes of Narcolepsy?
Type 1 narcolepsy has been linked to low levels of hypocretin (a type of chemical) within the brain, which plays an important role in regulating your sleep-wake cycles. Hypocretin also helps to transmit signals within the nervous system, and so it can be linked to cataplexy and muscle functions. Research suggests that these low levels of hypocretin can be linked to certain autoimmune disorders, family history or sometimes traumatic brain injuries, infections or tumours in parts of the brain that regulate wakefulness and REM sleep.
The exact cause of Type 2 narcolepsy is currently unknown.
What conditions could be confused with Narcolepsy?
Cataplexy can be misdiagnosed as a seizure disorder. The difference between cataplexy and seizures is that people are awake during cataplexy.
The symptoms of narcolepsy when presented to a doctor might also be confused with those of idiopathic hypersomnia, sleep apnea and Kleine-Levin syndrome. Symptoms similar to those of narcolepsy might develop after certain developments like brain tumours, head trauma and hardening of arteries in the brain. So, if you suspect you have narcolepsy, speak to your doctor about conducting the proper diagnostic tests in order to be sure.
How is Narcolepsy diagnosed?
To confirm a diagnosis of narcolepsy, your doctor might refer to your detailed medical history, family medical history, and analyse the symptoms you are experiencing. Your doctor could ask you to keep a sleep journal for a couple of weeks, to track your symptoms and sleep times.
You might also be referred to a neurologist to carry out physical examinations that would rule out other neurological conditions that might be causing your symptoms. There are two specialised tests that can be used to diagnose narcolepsy: the polysomnogram (PSG) and multiple sleep latency test (MSLT).
A PSG test is done during sleep and continually measures your brain wave changes and muscle activity, breathing rate and eye movements to show if rapid eye movement (REM) sleep happens early in the sleep cycle. It is useful in showing if your symptoms are not from narcolepsy but from another condition instead.
A MSLT test measures your daytime sleepiness through assessing how quickly you fall asleep and whether you enter REM sleep in 5 short naps, every 2 hours throughout the day. If you fall asleep in less than 8 minutes on average, you might have EDS.
Your doctor might also perform a lumbar procedure in order to withdraw a sample of your cerebrospinal fluid (the fluid that fills the spaces around your brain and spinal cord), to measure your hypocretin levels, which almost always mean Type 1 narcolepsy.
How can I manage my Narcolepsy?
As of now, narcolepsy cannot be cured. Instead, it must be managed in the long term through reducing the symptoms through medications and lifestyle changes.
Your doctor might prescribe medicine like modafinil, sodium oxybate, amphetamine-like stimulants and antidepressants.
Modafinil is normally first prescribed as it is not as addictive as other drugs and doesn’t have as many side-effects. It is a central nervous system stimulant and can reduce daytime drowsiness and improve your alertness and productivity. However, it has been linked to irregular heartbeat and increase in blood pressure, so you will probably need to be regularly monitored during intake of modafinil.
Sodium oxybate can improve the effects of cataplexy and help you to sleep better at night, reducing daytime sleepiness. However, distribution is tightly restricted due to safety concerns.
Amphetamine-like stimulants can help to alleviate EDS, but these must be carefully monitored as well for side effects like nighttime sleep disruption, irritability and nervousness.
Antidepressants can help to control cataplexy, but these also have serious side effects like impotence, high blood pressure and heart rhythm irregularities.
If you suspect that you have narcolepsy, book an appointment with your doctor to run some tests and find out more about the treatment options available for you.
Living with Narcolepsy
Although this condition might sound serious and diagnosis might seem scary at first, don’t worry, because it can be successfully managed with treatments, so that you can minimise the impact it has on your everyday life.
You can consider making a few lifestyle changes, like reducing the effects of EDS through taking frequent naps throughout the day, avoiding medicines that cause drowsiness, sticking to a regular bedtime routine, and ensuring you have a comfortable sleeping environment. You should also avoid caffeine, alcohol, and exercising just before bed.
References
- Do I Have Narcolepsy? (2020, December 3). National Sleep Foundation. https://www.thensf.org/do-i-have-narcolepsy/
- Narcolepsy – NORD (National Organization for Rare Disorders). (2015). NORD (National Organization for Rare Disorders); NORD. https://rarediseases.org/rare-diseases/narcolepsy/
- Narcolepsy – Symptoms, Causes, Treatment. (n.d.). Sleep Foundation. https://www.sleepfoundation.org/narcolepsy
- Narcolepsy Fact Sheet | National Institute of Neurological Disorders and Stroke. (2019). Nih.Gov. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Narcolepsy-Fact-Sheet
- Overview – Narcolepsy. (2019). NHS. https://www.nhs.uk/conditions/narcolepsy/
- Wise, M. S., Arand, D. L., Auger, R. R., Brooks, S. N., & Watson, N. F. (2007). Treatment of Narcolepsy and other Hypersomnias of Central Origin. Sleep, 30(12), 1712–1727. https://doi.org/10.1093/sleep/30.12.1712