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:
- Sleep apnea
- Restless legs syndrome
What is insomnia?
Insomnia is a sleep disorder in which people have difficulty falling or staying asleep. 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, due to not sleeping well
Insomnia varies in how long it lasts and how often it occurs. About 50 percent of adults experience occasional bouts of insomnia and 1 in 10 suffers from chronic insomnia. Insomnia can occur by itself or can be associated with medical or psychiatric conditions. Insomnia can be short-term (acute or adjustment 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 or adjustment 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 potentially 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.
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 back of the throat collapses during sleep. Symptoms of OSA may include snoring, daytime sleepiness, fatigue, restlessness during sleep, gasping for air while sleeping, and trouble concentrating.
- In central sleep apnea (CSA), the airway is not blocked, but the brain fails to tell the body to breathe. This type is called central apnea because it is related to the function of the central nervous system. People with CSA may gasp for air but mostly report recurrent awakenings during night.
What is restless legs syndrome?
Restless legs syndrome (RLS) is a sleep disorder that causes an intense, often irresistible urge to move the legs. 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 and stay asleep. It can be associated with problems with daytime sleepiness, irritability and concentration. 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. Some patients with narcolepsy experience sudden muscle weakness with laughter or other emotions.
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 sleep study can be done at home (home sleep testing) for select patients. The recordings become data that are analyzed by a qualified physician to determine whether or not you have a sleep disorder.