In people who have sleep apnea (also referred to as sleep-disordered breathing), breathing briefly stops or becomes very shallow during sleep. This change is caused by intermittent blocking of the upper airway, usually when the soft tissue in the rear of the throat collapses and partially or completely closes the airway. Each breathing stop typically lasts 10 - 20 seconds or more and may occur 20 - 30 times or more each sleeping hour.
“I have sleep apnea. In the past, I used to arrange my schedule around whether I’ve had enough sleep. Now I don’t worry about that.
Starting on continuous positive airway pressure and medication have changed my life - now I’m excited to wake up and face each day after a night of restful sleep.”
If you have sleep apnea, not enough air can flow into your lungs through the mouth and nose during sleep, even though breathing efforts continue. When this happens, the amount of oxygen in your blood decreases. Your brain responds by awakening you enough to tighten the upper airway muscles and open your windpipe. Normal breaths then start again, often with a loud snort or choking sound.
Although people who have sleep apnea typically snore loudly and frequently, not everyone who snores has sleep apnea. (See “Is Snoring a Problem?”)
Because people who have sleep apnea frequently arouse from deeper sleep stages to lighter sleep during the night, they rarely spend enough time in deep, restorative stages of sleep. They are therefore often excessively sleepy during the day. Such sleepiness is thought to lead to mood and behavior problems, including depression, and such sleepiness more than triples the risk of being in a traffic or workrelated accident.
The many brief drops in blood-oxygen levels can be associated with morning headaches and decreased ability to concentrate, think properly, learn, and remember. In sleep apnea, the combination of the intermittent oxygen drops and reduced sleep quality triggers the release of stress hormones. These hormones in turn raise your blood pressure and heart rate and boost the risk of heart attack, stroke, irregular heart beats, and congestive heart failure. In addition, untreated sleep apnea can lead to altered energy metabolism that increases the risk for developing obesity and diabetes.
Anyone can have sleep apnea. It is estimated that at least 12 - 18 million American adults have sleep apnea, making it as common as asthma. More than one-half of the people who have sleep apnea are overweight. Sleep apnea is more common in men. More than 1 in 25 middle-aged men and 1 in 50 middle-aged women have sleep apnea along with excessive daytime sleepiness. About 3 percent of children and 10 percent or more of people over age 65 have sleep apnea. This condition occurs more frequently in African Americans, Asians, Native Americans, and Hispanics than in Caucasians.
More than one-half of all people who have sleep apnea are not diagnosed. People who have sleep apnea generally are not aware that their breathing stops in the night. They just notice that they don’t feel well rested when they wake up and are sleepy throughout the day. Their bed partners are likely to notice, however, that they snore loudly and frequently and that they often stop breathing briefly while sleeping. Doctors suspect sleep apnea if these symptoms are present, but the diagnosis must be confirmed with overnight sleep monitoring. (See “How Are Sleep Disorders Diagnosed?”) This monitoring will reveal pauses in breathing, frequent sleep arousals, and intermittent drops in levels of oxygen in the blood.
Like adults who have sleep apnea, children who have this disorder usually snore loudly, snort or gasp, and have brief stops in breathing while sleeping. Small children often have enlarged tonsils and adenoids that increase their risk for sleep apnea. But doctors may not suspect sleep apnea in children because, instead of showing the typical signs of sleepiness during the day, these children often become agitated and may be considered hyperactive. The effects of sleep apnea in children may include diminished school performance and difficult, aggressive behavior.
Revision date: July 7, 2011
Last revised: by Tatiana Kuznetsova, D.M.D.