Narcolepsy and sleep apnea are conditions that can cause someone to feel tired during waking hours. However, their symptoms, causes, and treatments are very different.
Narcolepsy is a rare condition that causes attacks of severe sleepiness, which can happen at any time. Some people also experience a sudden loss of muscle tone, which is known as cataplexy.
This article looks at the differences between narcolepsy and sleep apnea, the link between these sleep disorders, and how doctors diagnose them.
Sleep apnea is a common condition that causes a person’s breathing to stop or become very shallow temporarily during sleep. Doctors call these instances “breathing pauses,” and they can last from a couple of seconds to a couple of minutes.
People with sleep apnea have frequent breathing pauses that can occur 30 times or more per hour. There are several types of sleep apnea, including:
- Obstructive sleep apnea (OSA): This is the most common form of sleep apnea, and it occurs due to a blockage in the upper airways.
- Central sleep apnea: This condition occurs when the brain
does not sendthe signals required for breathing.
- Complex sleep apnea syndrome: This refers to a mix of obstructive and central sleep apnea.
Narcolepsy is a neurological disorder that affects the brain’s ability to control its sleep-wake cycle. This can result in people involuntarily and suddenly falling asleep during waking hours, even when they are performing activities that require concentration, such as driving.
There are two types of narcolepsy: type 1 and type 2. Type 1 occurs with cataplexy, which is a loss of muscle tone. Cataplexy causes part of the body, or the whole body, to become limp. Type 2 occurs without cataplexy.
Narcolepsy symptoms typically start in childhood or young adulthood, but they can begin at any time in life. Many researchers believe that the condition often goes underdiagnosed or misdiagnosed.
The following table compares the symptoms of sleep apnea with those of narcolepsy:
|excessive daytime sleepiness||excessive daytime sleepiness that may occur suddenly|
|gasping or choking noises during sleep||cataplexy, which strong emotions such as fear, laughter, stress, anger, or excitement |
|loud snoring||vivid dreams, sleep paralysis, or hallucinations|
|dry mouth when waking||acting out dreams|
|frequent waking during sleep||difficulty sleeping at night|
|difficulty focusing or remembering||automatic behaviors, which occur when a person briefly falls asleep but carries on with their activity|
Research suggests that OSA is common among those with narcolepsy. An older
However, sleep apnea does not cause narcolepsy. Narcolepsy is a neurological condition that occurs when the brain cannot regulate its sleep-wake cycle.
Doctors are not sure why sleep apnea is common in people who have narcolepsy, but it may be related to the other sleep disruptions that people with narcolepsy often experience.
People with type 1 narcolepsy have
Doctors are not sure why some people have low levels of hypocretin, but several factors may play a role:
- Autoimmune disease: People with type 1 narcolepsy often have autoimmune conditions, in which the immune system attacks healthy cells. Researchers believe that the immune system may also attack the cells that create hypocretin, leading to a deficiency.
- Family history: In most cases, narcolepsy is not related to a family history of the condition. However, about 10% of people say they have a family member who also has narcolepsy symptoms. This suggests that there may be a genetic component in some cases.
- Brain injury or disease: Rarely, narcolepsy develops after an injury damages an area of the brain that regulates sleep or as a result of another condition that affects the brain, such as a tumor.
People with type 2 narcolepsy usually have normal levels of hypocretin. Researchers have yet to discover what causes this condition.
There are many reasons why a person may feel excessive tiredness during waking hours. Other factors that can contribute to this symptom
- insufficient sleep
- traumatic brain injuries
- certain medications, such as antihistamines, antidepressants, and beta-blockers
- other sleep disorders, such as circadian rhythm disorder
A doctor can diagnose the cause of excessive sleepiness, frequent waking during the night, and other symptoms that may indicate sleep apnea or narcolepsy. They will begin the diagnostic process by:
- performing a physical examination
- taking a medical history
- asking the person to keep a sleep journal to record their symptoms
However, sleep studies are the
If a doctor suspects narcolepsy, they may recommend a combination of a polysomnography (PSG) and a multiple sleep latency test (MSLT).
A PSG is a type of sleep study that tracks breathing, eye movements, brain activity, and muscle movements during sleep. It can detect signs of narcolepsy and other conditions that can affect sleep, including sleep apnea.
An MSLT typically occurs the morning after the PSG. The person will take a nap
Sometimes, doctors also carry out a lumbar puncture to test the hypocretin levels in a person’s cerebrospinal fluid.
Doctors use a range of treatments to address these sleeping disorders.
Sleep apnea treatment
The possible treatments for OSA include:
- lifestyle changes, such as quitting smoking or maintaining a moderate weight
- breathing devices
- surgery, if OSA is due to enlarged tonsils or adenoids
The breathing device that doctors
Mouthpieces for sleep apnea hold the lower jaw forward enough to keep the airway open. If OSA treatment does not help, this could be a sign that someone has another type of sleep apnea, another sleep disorder, or a condition such as narcolepsy.
There is no cure for narcolepsy, but medication can
- modafinil (Provigil)
- amphetamine-like stimulants
- tricyclic antidepressants
- selective serotonin reuptake inhibitors
- noradrenergic reuptake inhibitors
An individual may also need to make lifestyle adjustments, such as avoiding caffeine before bed, taking short naps, exercising daily, and maintaining a regular sleep schedule to help manage their symptoms.
Sleep apnea and narcolepsy both cause daytime sleepiness. However, sleep apnea causes tiredness as a result of sleep disturbances, which occur due to frequent pauses in breathing. People with the condition often snore, make gasping or choking noises in their sleep, or wake up with a dry mouth.
Narcolepsy is a neurological disorder that causes intense sleepiness that can lead someone to fall asleep suddenly during daily activities. It can also result in insomnia, vivid dreams, sleep paralysis, and hallucinations. It is possible for someone to have both sleep apnea and narcolepsy, but sleep apnea on its own is far more common.
People who are concerned about their symptoms should consult a doctor for a diagnosis, especially if excessive sleepiness is affecting either their mental health or activities that could be dangerous, such as driving.