What are sleep disorders and how common are they?
Sleep disorders are conditions that prevent a person from getting restful sleep and, as a result, can cause daytime sleepiness and dysfunction. There are approximately eighty different types of sleep disorders. About 70 million Americans suffer from them. The most important sleep disorders are:
- Insomnia
- Sleep apnea
- Restless legs syndrome
- Narcolepsy
What is insomnia?
Insomnia is a sleep disorder of difficulty initiating or maintaining sleep. People with insomnia have one or more of the following symptoms:
- difficulty falling asleep
- waking up often during the night and having trouble going back to sleep
- waking up too early in the morning
- having unrefreshing sleep
- having at least one daytime problem such as fatigue; sleepiness; problems with mood, concentration; accidents at work or while driving, etc.
Insomnia varies in how long it lasts and how often it occurs. Insomnia can be short-term (acute insomnia) or can last a long time (chronic insomnia). It can also come and go, with periods of time when a person has no sleep problems. Acute insomnia can last from one night to a few weeks. Insomnia is called chronic when a person has insomnia at least three nights a week for a month or longer.
What is sleep apnea?
Sleep apnea is a serious sleep disorder that occurs when a person’s breathing is interrupted during sleep. People with untreated sleep apnea stop breathing repeatedly during their sleep, sometimes hundreds of times during the night. There are two types of sleep apnea: obstructive and central. Obstructive sleep apnea (OSA) is the more common of the two. It is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses during sleep. In central sleep apnea, the airway is not blocked but the brain fails to signal the muscles to breathe due to instability in the respiratory control center. This type is called central apnea because it is related to the function of the central nervous system.
What is restless legs syndrome?
Restless legs syndrome (RLS) is a sleep disorder that cause tingling, pulling, creeping, or painful sensations in the legs at night. This sensation is brought on by resting such as lying down in bed, sitting for prolonged periods such as while driving or at a theatre. RLS typically occurs in the evening, making it difficult to fall asleep. Often, people with RLS want to walk around and shake their legs to help relieve the uncomfortable sensation.
What is narcolepsy?
Narcolepsy is a neurological disorder of sleep regulation that affects the control of sleep and wakefulness. People with narcolepsy experience excessive daytime sleepiness and intermittent, uncontrollable episodes of falling asleep during the daytime. These sudden sleep attacks may occur during any type of activity at any time of the day. Narcolepsy usually begins between the ages of 15 and 25, but it can become apparent at any age. In many cases, narcolepsy is undiagnosed and, therefore, untreated.
How are sleep disorders diagnosed?
If you suspect that you may have a sleep disorder, discuss your symptoms with your primary care doctor. He or she can perform a physical exam and help you identify the difficulties you are having with sleep. Keeping a sleep diary for two weeks may be helpful to your doctor. Some illnesses can cause disturbed sleep, so your doctor may order tests to rule out other conditions.
If your doctor suspects that you have a sleep disorder, he or she may refer you to a sleep disorder clinic. A sleep specialist will review your symptoms and may suggest that you undergo a sleep study.
A sleep study or polysomnogram (PSG) is a multiple-component test that electronically transmits and records specific physical activities while you sleep. The recordings become data that are analyzed by a qualified physician to determine whether or not you have a sleep disorder.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 11/21/2008...#11429