Causes Of Narcolepsy

People with this condition experience excessive daytime sleepiness, but usually do not have muscle weakness caused by emotions. They also usually have less severe symptoms and have normal levels of the brain hormone hypocretin. A condition known as secondary narcolepsy can result from an injury to the hypothalamus, an area deep in the brain that helps regulate sleep. In addition to experiencing the typical symptoms of narcolepsy, individuals may also have severe neurological problems and sleep every night for long periods of time. A multiple sleep latency test is done to distinguish between physical fatigue and excessive daytime sleepiness and to check for narcolepsy. They are given the opportunity to take five naps at 2-hour intervals.

A deficiency of hypocretin causes excessive drowsiness, and the characteristics of REM sleep (also called “dreamy sleep”) are present during waking up. A clinical examination and detailed medical history are essential for the diagnosis and treatment of narcolepsy. The doctor may ask people to keep a sleep diary by noting sleep times and symptoms over a period of one to two weeks. Although none of the main symptoms are unique to narcolepsy, cataplexy is the most specific symptom and is almost non-existent in other diseases.

In some individuals, up to a percentage of hypocretin-producing neurons in the hypothalamus are lost. People who have narcolepsy with cataplexy have the lowest levels of hypocretin.

In addition to drug therapy, many people have benefited from behavioral change. Regular sleep habits are important for people with narcolepsy, including ensuring regular bedtime and preventing sleep disturbances. If possible, taking regular naps throughout the day can help control excessive daytime sleepiness. Affected individuals should consider talking to their doctors about establishing appropriate sleep schedules.

When cataplexy is present, the cause is usually the loss of brain cells that produce hypocretin. Although the reason for this cell loss is unknown, it appears to be related to abnormalities in the immune system. Autoimmune diseases occur when the body’s immune system turns against itself and mistakenly attacks healthy cells or tissues. Modafinil Researchers believe that in individuals with narcolepsy, the body’s immune system selectively attacks brain cells that contain hypocretin due to a combination of genetic and environmental factors. In a test-tube model, clarithromycin was found to return GABA system function to normal in people with primary hypersomnia.

Patients with narcolepsy were found to have little or no hypocretin in CSF. Postmortem pathological examination of the brains of people with narcolepsy with cataplexy has shown a dramatically reduced number of hypocretin neurons. It is theorized that hypocretin deficiency causes instability of sleep and wake states, preventing the person from maintaining continuous sleep or wakefulness. The brain sends signals to the muscles and limbs during this phase of sleep to keep the muscles static and prevent us from representing our dreams.

The diagnostic criteria of ICSD-3 state that the individual must experience “daily periods of unsustainable need for sleep or falling asleep during the day” for both subtypes of narcolepsy. A diagnosis of narcolepsy type 2 requires an average sleep latency of less than 8 minutes, two or more SOREMs, and a hypocretin-1 concentration of more than 110 pg/mL. In addition, the findings of hypersomnolence and sleep latency cannot be better explained by other causes. There is a strong link with certain genetic variants, which can predispose T cells to respond to orexin-releasing neurons after being stimulated by infection with H1N1 flu. The hypocretin system plays an important role in the pathophysiology of human narcolepsy.

In addition, they will fall asleep dreaming even during a short nap; something a healthy, well-sleeping individual will not do. Hypothyroidism, delayed sleep phase syndrome, periodic movement disorder of the limbs, depression, hypoglycemia and other conditions can also cause excessive daytime sleepiness. Idiopathic hypersomnia is a rare condition characterized by episodes or extreme drowsiness that occur for no identifiable reason. The condition differs from narcolepsy in that affected individuals do not experience sudden episodes of sleep or develop cataplexy. In addition, affected individuals do not feel refreshed after a nap.

When tested, people with narcolepsy fall asleep quickly, get into REM sleep early, and can often wake up at night. The polysomnograph also helps detect other possible sleep disturbances that can cause daytime sleepiness. When unavailable, the brain allows REM sleep phenomena to enter normal periods of wakefulness.