Научная электронная библиотека

Монографии, изданные в издательстве Российской Академии Естествознания

Английский язык для клинических психологов

Ольшванг О. Ю.,

How Common is Narcolepsy?

Narcolepsy was first described by the French physician Jean Gelineau in 1880. It is now thought to affect about 1 in 2,000 people. The symptoms of narcolepsy usually begin in the teens or early twenties, but it may rarely first occur in children or even the elderly. It affects men as commonly as women.

There may be some ethnic variation, as it is quite uncommon among Israeli Jews (with a prevalence of only 0,002 %) and occurs relatively frequently among the Japanese (with a prevalence of 0,15 %). A study of 18,000 people in five European countries found an estimated prevalence of 0,047 %.

There may be a genetic component to the disorder as narcolepsy can be more commonly found among relatives of people with the disorder. However, the environment seems to have an important role as well (only 25 percent of identical twins will both have the disorder).

What Causes Narcolepsy?

Narcolepsy appears to occur because of a loss of the chemical hypocretin in an area of the brain called the hypothalamus. The nerve cells (or neurons) in the brain that rely on this chemical regulate sleep and alertness. Hypocretin is thought to promote wakefulness and maintain normal muscle tone, so it makes sense that its loss would lead to the sudden weakness seen in cataplexy.

It is thought that the body’s immune system, which typically is responsible for fighting infection, may turn against the hypocretin-containing neurons. In narcoleptics, studies have shown that 85 to 95 percent of these neurons are lost. When these cells are damaged, there are frequent, inappropriate transitions between sleep and wakefulness.

Narcolepsy may also be caused by rare lesions within the brain that result because of tumors, strokes, or other insults.

Diagnosis and Treatment of Narcolepsy

If you believe you may be suffering from narcolepsy, it is important to speak with your doctor and a sleep specialist. After a careful evaluation and examination, you may need to undergo other testing to establish the diagnosis of narcolepsy. In general, these tests will include an overnight sleep study called a polysomnogram and a study the next day called a multiple sleep latency test (MSLT).

In addition, there may be laboratory tests (including a genetic test). If your sleep studies are negative but there is still a strong suspicion for narcolepsy, it may be important to test your cerebrospinal fluid for the chemicals orexin and hypocretin.

There is no cure for narcolepsy, but treatments may help to alleviate some of the symptoms. Excessive daytime sleepiness may be alleviated with stimulants such as Ritalin, Provigil, and Nuvigil. A medication called sodium oxybate can effectively treat the sleepiness as well as cataplexy.

If you have narcolepsy, it is best to review the treatment options with your physician to ensure that the appropriate medication is selected to manage your particular symptoms.

Match the terms with their definitions

sleeping pill	a pill or tablet containing a sedative drug, such as a barbiturate, used to induce sleep
To disrupt	to interrupt the progress of smth
drowsy	heavy with sleepiness; sleepy
insomnia	chronic inability to fall asleep or to enjoy uninterrupted sleep
sleepwalking	a condition that is characterized by walking while asleep or in a hypnotic trance
night terrors	a condition in which a person, usually a child, suddenly starts from sleep in a state of extreme fear but cannot later remember the incident
hypothalamus	a neural control centre at the base of the brain, concerned with hunger, thirst, satiety, and other autonomic functions
narcolepsy	a rare condition characterized by sudden and uncontrollable episodes of deep sleep
sleeper	a person, animal, or thing that sleeps
sweating	the sensible elimination of fluid through the pores of the skin, which is visible as droplets on the skin

Fill in the gaps in the sentences with the appropriate words from the box

Alertness (1); hypothalamus (5); alleviate (6); cataplexy (3); sleep disorder (4); neurons (7); lesions (2);

1. The nerve cells (or neurons) in the brain that rely on this chemical regulate sleep and …

2. Narcolepsy may also be caused by rare … within the brain that result because of tumors and strokes.

3. Hypocretin is thought to promote wakefulness and maintain normal muscle tone, so it makes sense that its loss would lead to the sudden weakness seen in …

4. Night terrors are most frequently seen in very young children (between the ages of 2 and 6), but people of any age can be affected by this … …

5. Narcolepsy appears to occur because of a loss of the chemical hypocretin in an area of the brain called the ?

6. There is no cure for narcolepsy, but treatments may help to … some of the symptoms.

7. In narcoleptics, studies have shown that 85 to 95 percent of these … are lost.

Say if these statements are true or false

	true	false
Narcolepsy was first described by the British physician Jean Gelineau in 1880.
There may be a genetic component to the disorder as narcolepsy can be more commonly found among relatives of people with the disorder.
Narcolepsy may also be caused by rare lesions within the brain that result because of tumors and strokes.
Night terrors are never seen in very young children
Typical treatments include exercises and reading
Additionally, people with narcolepsy may experience intense hallucinations while transitioning to sleep
Sleep apnea is the second most common sleep disorder and affects approximately 1 million Americans.