SUNY Downstate Medical Center
Sleep Disorders Center
What is Sleep Apnea?
Sleep apnea is a common disorder that affects more than 18 million people in the United States, both adults and children, many of them undiagnosed. There are three types of sleep apnea-obstructive, central, and mixed. Of these, obstructive sleep apnea (OSA) is the most common, occurring in approximately 2 percent of women and 4 percent of men over the age of 35.
Older obese men seem to be at higher risk, although as many as 40% of people with obstructive sleep apnea are not obese. Drinking alcohol or using sedatives before sleep may make one more likely to have an episode of apnea.
What Happens During Sleep Apnea?
Normally, the muscles of the upper part of the throat help keep the airway open and allow air to flow into the lungs. Even though these muscles usually relax during sleep, the upper throat remains open enough to let air pass by. However, some people have a narrower throat area and, during sleep, relaxation of the muscles causes the airway passage to close. This prevents air from getting into the lungs. Loud snoring and labored breathing occur and breathing can stop for a short period of time. This is called apnea.
During deep sleep, people with sleep apnea literally stop breathing repeatedly, often for a minute or longer, and as many as hundreds of times during a single night. An episode of apnea is followed by a sudden attempt to breathe and a transition to a lighter stage of sleep. A person with obstructive sleep apnea usually snores heavily soon after falling asleep. The snoring continues at a regular pace for a period of time, often becoming louder, but is then interrupted by a long silent period during which there is no breathing. This is followed by a loud snort and gasp, and the snoring returns. This pattern repeats frequently throughout the night, resulting in fragmented sleep that is not restful, and excessive daytime sleepiness.
An individual with sleep apnea rarely remembers the episodes of apnea during the night, even upon awakening.