As many as 18 million Americans suffer obstructive sleep apnea, a condition in which people stop breathing in their sleep. Many of them, particularly the ones who first showed signs of the condition as adults, are obese, or otherwise large in size. Even people at a typical weight are at risk for apnea if they have large necks. A man with a neck larger than 17 inches, or a woman with a neck larger than 16 inches, has a heightened risk regardless of weight.
There are two things that cause someone to stop breathing at night. In obstructive sleep apnea, the throat folds up and blocks the airway. It is by far the more common of the two types. The other is called central sleep apnea. The airway is unobstructed, but the muscles that control breathing don’t get the proper signals from the brain and so fail to function.
Since people with apnea briefly wake up when breathing is cut off, the condition can keep patients from getting restful sleep, meaning a person with apnea can get what he or she thinks is a full night’s sleep and nonetheless wake up tired. Consequently, people with sleep apnea show the effects of sleep deprivation: poor focus, impaired memory, and generally walking around in a fog. People with apnea often snore loudly; in fact, many cases of apnea go undiagnosed except for the patients’ partners noticing the snoring. The intermittent lack of oxygen also directly affects the brain, raising stroke risk. This damage becomes noticeable after as little as one month.
Interestingly, while patients with sleep apnea are more prone to heart disease than the general population, there is some evidence that they are better able to survive heart attacks. Apnea patients seem to experience less damage to the heart tissue during a heart attack, meaning the heart attack itself is less severe.
The primary treatment for sleep apnea is a device called a continuous positive airway pressure, or CPAP, machine, that helps keep a patient’s airway open while he or she sleeps. Oral appliances are less reliable, but in people for whom they are effective, they’re more comfortable and less cumbersome than CPAP machines.