Introduction

Narcolepsy is a neurological disorder that affects the body’s sleep-wake cycles by blurring the boundary between the two. Therefore, people with the disorder often show characteristics of sleep during wakeful episodes.

They will mostly experience excessive daytime sleepiness, sudden onset of cataplexy (which is the muscle paralysis which is suppose to occur during REM sleep), sleep paralysis, and hallucinations. In severe cases, they can fall asleep involuntarily while performing other tasks since they cannot remain awake for long periods. The condition is chronic; hence it cannot be cured. However, there are several medications and lifestyle changes that help people with this disorder, which can be use to manage their symptoms.

Symptoms of Narcolepsy

Narcolepsy occurs gradually and it is possible for people to have the disorder for several years unnoticed before it becomes apparent. The following are the most common symptoms for the disorder:

1. Excessive daytime sleepiness

People with the disorder are extremely drowsy during the day and might take naps frequently to try and offset the feeling. They will have intermitted alertness regardless of the tasks they are engaged in and will nod off frequently. Taking short daytime naps appears not to help with the condition as the sleepiness recurs within a short while.

2. Sleep attack

The disorder can cause an overwhelming level of sleepiness leading to an individual falling asleep abruptly. The person could be engaged in a task or talk and suddenly doze off. After recovering from the sleep attack, the individual will be confused with a poor recollection of what they were doing before the attack. This is mainly accompanied by the faulty triggering of REM sleep in the brain during wakeful episodes of a day.

3. Mental fogginess

A person with narcolepsy has difficulties in concentrating. This is because of flaws in the part of the brain that regulates one’s level of consciousness. Hence, the individual suffering from the disorder will often lack mental clarity and become unable to focus on one thing.

4. Sleep paralysis

It is normal for the body to be immobilized shortly after falling asleep to minimize movements during a sleeping episode. Shortly before waking up, the brain restores mobility to the body. However, people with narcolepsy can wake up before the body exits the temporary paralysis state hence experience sleep paralysis. Sleep paralysis manifests as a state in which one is awake but unable to move or speak. During a paralysis episode, it is possible for individuals to hear, feel, or see imaginary things that often induce a lot of fear. For instance, one might see supernatural creatures or hear strange voices.

5. Cataplexy

There are two kinds of narcolepsy: type 1 and type 2. Type 1 narcolepsy occurs with cataplexy while type 2 does not. In type 1, individuals lose muscle control suddenly after feeling intense emotions such as excitement or anger. People with the illness might experience unexpected and uncontrollable muscle weakness lasting for several minutes. They might fall down helplessly and remain immobile until their muscles regain strength. The individual may stay awake during the experience while completely aware of the incident but then fall asleep shortly afterward.

6. Hallucinations

Normally, people transition from wakefulness to NREM and then REM sleep. However, narcolepsy causes the immediate onset of REM sleep during which dreams occur. Hence, people with the disorder will often report having vivid and frightening sensory hallucinations while falling asleep. This is a result of partial wakefulness as REM sleep kicks in leading to dreams that often feel real to the person.

 

Causes of Narcolepsy

The exact cause of the disorder has not yet been determined but medical professionals believe the following could be potential influencing factors.

1. Autoimmune disorders

Type 1 narcolepsy, which is characterized by cataplexy, is said to be caused by the lack of a chemical called hypocretin that is responsible for keeping the brain alert and also regulating sleep-wake cycles. The chemical is produced by a cluster of cells in the hypothalamus. Patients with Type 1 narcolepsy have been found to have little or none of these cells. Without this vital neurotransmitter, such people will have distorted sleep-wake cycles. They will also be unable to stay awake for long periods because the brain is left unable to stop REM sleep phenomena during wakeful periods. The cause of the loss or absence of these cells has not yet been ascertained; however, it has been thought to occur due to autoimmune disorders. The immune system is normally able to tell apart normal and foreign cells inside the body, and fight them off. However, there have been cases where the body also mistakenly identifies some of its own cells as foreign and fights them. Researchers say that it is possible for the unique cluster of cells that produce hypocretin to be wrongly identified as foreign cells and, hence, be destroyed by the body’s defense system.

2. Head injuries

Head trauma has also been associated with cases of narcolepsy, particularly when the hypothalamus is affected. The hypothalamus plays a role in ensuring wakefulness by sending signals to the cerebral cortex to remain activated. Similarly, the hypothalamus is also responsible for reducing brain activity causing the body to transition to sleep. Head injuries have been known to cause hypothalamic dysfunction thus impairing its ability to correctly regulate sleep and wake episodes. Hence, when the hypothalamus is dysfunctional, narcolepsy can set in as individuals may fall asleep erratically.

3. Birth defects

There are people born with birth defects in the brain, and specifically in the hypothalamus region. Hence, the vital brain region fails to function as expected in the regulation of sleep-promoting and wake-promoting neurons. This leads to sleep befalling people at a time they are normally supposed to be awake.

4. Genetics

Doctors say that about 1% of narcolepsy cases are inherited from parents. Therefore, people with a family history of the disorder are more likely to develop it. Statistically, one is 20 to 40 times more likely to develop the condition if another family member in their lineage has or had it.

5. Swine flu and the 2009 Pandemrix vaccine

In 2009, during an outbreak of swine flu, a pharmaceutical company developed Pandemrix, an H1N1 strain that was administered as a swine flu vaccine in Europe. However, there was an increase in narcolepsy cases in the populations that received the treatment from the company’s strain. A study found out that the vaccine caused the production of antibodies that also targeted the brain cells that produced hypocretin. Similarly, the swine flu itself led to the destruction of these cells as it instigated a massive production of antibodies that would mount an attack and that would eventually enter the brain and latch on hypocretin receptors.

Diagnosis of Narcolepsy

The condition commonly starts manifesting from 10 years of age. Since its symptoms occur gradually and worsen as one grows older, it is often misdiagnosed as it can be confused with other illnesses at early stages. To diagnose a case of narcolepsy, doctors will use the following tools and techniques:

1. Sleep history

Physicians will be interested in learning more about one’s sleep history so that they can identify the condition correctly. Hence, in most visits, doctors will inquire about the following:

  1. Feelings of sleepiness during the day
  2. Sleep duration at night
  3. Whether one feels rested adequately after nighttime sleep
  4. Whether daytime naps are refreshing
  5. Whether one experiences unusual sensations as they fall asleep (hallucinations)
  6. Whether one is temporarily unable to move when they wake up (sleep paralysis)
  7. Whether highly emotive states lead to weakness and sleepiness (cataplexy)

 

Unlike some sleep disorders, people with narcolepsy are usually conscious when the symptoms manifest and will be able to inform doctors about their onset.

2. Medical history

Doctors might want to confirm whether the patient has had brain trauma in the past, which might have subsequently led to hypothalamic dysfunction. Therefore, they may inquire about previous hospital visits especially regarding injuries to the head.

3. Polysomnography

Also known as a sleep study, Polysomnography is an overnight test that monitors different parameters during sleep to identify sleep patterns or causes of disturbances. The test involves collecting data about brain waves, blood oxygen levels, heart rate, eye movements, and leg movements when one is sleeping. Individuals with narcolepsy will show erratic sleep patterns as they transition from wakefulness to REM sleep, having skipped the NREM sleep phase.

4. Electroencephalography (EEG)

The EEG is a non-invasive machine used to measure electrical activity in the brain using electrodes placed on the scalp. Doctors can use the device to ascertain whether one is in REM or non-REM sleep. On the EEG, the former (REM) registers high electrical activity while the latter (non-REM) shows reduced activity on an EEG. In narcolepsy cases, patients will register high brain activity immediately after falling asleep which is contrary to normal situations whereby one transitions from wakefulness to non-REM sleep.

5. Multiple Sleep Latency Test (MSLT)

This test is used as a diagnostic tool used to measure the duration between the start of a nap and actual sleep onset. It confirms excessive sleepiness in individuals on the basis that, the sleepier one is, the shorter their sleep latency. The test is usually done over the course of five scheduled naps with two-hour intervals whereby the time taken to fall asleep is recorded. Narcolepsy patients will mostly feel sleepy and will not get refreshed by a nap hence they will show very little sleep latency.

Treatment Options for Narcolepsy

Currently, there is no available cure for this chronic disorder. However, there are several types of medication that can help people to manage the condition and lead normal lives. Doctors may suggest a combination of drugs to help patients manage different symptoms. Further, some lifestyle changes can help people deal with the disorder and also improve their quality of life. The following are the available treatment options:

1. Central Nervous System Stimulants

Doctors can prescribe CNS stimulants to help keep a patient awake and alert during wakeful episodes. Commonly, dexamphetamine, methylphenidate, or modafinil are used because they are not costly, are widely available, and have a high efficacy in keeping the brain alert once taken. However, they have to be prescribed by a physician since their overuse or abuse can lead to tolerance or side effects such as insomnia.

2. Antidepressant medication

Antidepressants are medication used to reduce cataplexy that normally occurs due to sudden mood changes, such as excitement or anger, and leads to the sudden loss of muscle strength. The drugs are used to stabilize one’s moods and prevent anxiety, hence prevent cataplexy. Common antidepressants include:

  1. Selective Serotonin Reuptake Inhibitors (SSRIs)
  2. Tricyclic Antidepressants (TCAs)
  3. Monoamine Oxidase Inhibitors (MAOIs)
  4. Noradrenaline And Specific Serotoninergic Antidepressants (NASSAs)

3. OTC stimulants

There are a few non-prescription drugs that can be bought over the counter to manage the excessive daytime sleepiness. Mostly, pharmacists will sell drugs that have 100mg – 200mg of caffeine to improve one’s alertness. Some of these drugs include Vivarin and NoDoz. They help keep the brain more alert but only for a short while since their effects wear out after a few hours.

4. Lifestyle changes

Narcolepsy symptoms can also be managed through the following lifestyle changes:

a) Good sleep hygiene

Good sleep hygiene ensures that one gets sufficient nighttime sleep and this can alleviate the excessive daytime sleepiness. It includes following a fixed daily routine, ensuring that the sleeping environment is quiet and dark, avoiding meals and stimulants before going to bed, and avoiding alcohol.

b) Self-care

Due to the high risk of possible harm due to reduced alertness, mental fogginess, and sudden falls due to cataplexy, people with narcolepsy should avoid environments or tasks that could place them in harm’s way. For instance, they should avoid driving as they may easily doze off and cause an accident.

c) Care from family and friends

It is best if people with narcolepsy are not in solitude, especially if they have cataplexy. A friend or family member should accompany them to help prevent injury in case a symptom such as sudden muscle weakness manifests. Further, narcolepsy patients might require support from their loved ones to avoid depression due to stigmatization and the manifestations of some symptoms in public.

Conclusion

Narcolepsy is a disorder accompanied by the lack of regulation in sleep-wake cycles, hence, leads to characteristics of sleep manifesting when one is expected to be fully awake. The condition comes with symptoms such as excessive daytime sleepiness, sleep attacks, mental fogginess, sleep paralysis, cataplexy, and hallucination. While the real cause of narcolepsy has not been ascertained, the disorder is believed to occur as a result of autoimmune disorders that destroy hypocretin-synthesis cells, head injuries, birth defects, genetics, and swine flu or a particular 2009 swine flu vaccine. Narcolepsy is diagnosed through the examination of one’s medical history and different sleep analyses. Though the condition cannot be cured, its symptoms are treated or alleviated using CNS stimulants, antidepressant, supplements, medication, OTC stimulants, and lifestyle changes.

 

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