American Sleep and Epilepsy Centers
Frequently Asked Questions
Q: What is sleep apnea?
A: The most common type of sleep disordered breathing, sleep apnea is a serious and potentially life-threatening condition that is far
more common than generally understood. First widely recognized in 1965, sleep apnea is a breathing disorder characterized by
interruptions of breathing during sleep, usually accompanied by loud snoring. It owes its name to a Greek word, apnea, meaning, "want of
There are two types of sleep apnea: central and obstructive. Central sleep apnea occurs when the brain fails to send the appropriate
signals to the breathing muscles to initiate respirations. Obstructive sleep apnea (OSA), which is far more common, occurs when air
cannot flow into or out of the person's nose or mouth despite respiratory efforts due to collapse and blockage of the airways. Mixed sleep
apnea is a combination of the two.
For people experiencing OSA, the number of involuntary breathing pauses or "apneic events" in a given night may be as high as 20 to 60
or more per hour, each lasting 10 seconds or longer. While these breathing pauses usually are accompanied by snoring, not everyone
who snores has this condition. The frequent interruption of restorative sleep often leads to excessive daytime sleepiness and may be
associated with an early morning headache.
Q: Who gets sleep apnea?
A: Sleep apnea occurs in all age groups and both sexes but is most common among middle-aged men. It has been estimated that as
many as 20 million Americans have sleep apnea. Published reports claim that 24 percent of middle-aged men and 9 percent of middle-
aged women have sleep apnea, along with excessive daytime sleepiness, while other studies report that 9 percent of the general
population has OSA. Less than 5 percent of sleep apnea sufferers have been diagnosed and treated. People most likely to have or
develop sleep apnea include those who snore loudly, are overweight, have high blood pressure, or have some physical abnormality in the
nose, throat, or other parts of the upper airway.
Q: What causes sleep apnea?
A: Collapse and blockage of the airway causes the interruptions in breathing during sleep. Apnea usually occurs when the throat muscles
and tongue relax during sleep and partially block the opening of the airway. When the muscles of the base of the tongue, the soft palate
and the uvula (the small fleshy tissue hanging from the center of the back of the throat) relax and sag, the airway becomes blocked,
making breathing labored and noisy and even stopping it entirely.
Obesity aggravates the narrowing of the airway and causes other changes which intensify OSA. With a narrowed airway, air cannot
easily flow into or out of the nose or mouth despite attempts to breathe. The results are heavy snoring, cessation of breathing for short
periods, and frequent arousals that reduce the amount of time spend in the deepest, most restful stages of sleep. Ingestion of alcohol and
sleeping pills also increases the frequency and duration of apneas.
Q: What are the implications of sleep apnea?
A: Apnea patients often suffer from excessive daytime sleepiness, with consequences such as impaired functioning, depression, memory
and judgment problems, resulting in a statistically higher involvement in traffic accidents. According to the National Highway Traffic Safety
Administration, people who are asleep at the wheel cause approximately 56,000 police-reported automobile crashes per year.
Sleep apnea has been shown to cause high blood pressure and may be associated with irregular heartbeat, heart attack and stroke,
each a potentially life-threatening condition. Every apneic event produces increases in systemic and pulmonary artery pressure.
According to a recent study by the American College of Cardiology, people who snore regularly are more at risk of developing
cardiovascular disease than those who do not snore. Another recent study reported in the New England Journal of Medicine found that
people who experience apneic events during sleep are up to three times more likely to develop high blood pressure, with the increased
risk proportional to the number of apneic events per night.
Q: What are the signs of sleep apnea?
A: The main symptoms of sleep apnea are chronic, loud snoring, gasping or choking episodes during sleep and excessive daytime
sleepiness (EDS). The latter can result in cognitive difficulties, irritability, mood changes, anxiety or depression. Another warning sign is
early onset of high blood pressure (hypertension). Possible predictors of OSA are obesity, a thick neck, family history, or anatomic
abnormalities in the upper airway or facial structure. Age, male gender, smoking and use of alcohol or sedatives also have been
correlated to an increased risk of OSA.
Q: How is normal breathing restored after an apnea episode?
A: During the apneic event,. the increased airway resistance is sensed by the brain and triggers an arousal out of deep sleep. With each
arousal, a signal is sent from the brain to the upper airway muscles to open the airway; and breathing is resumed, often with a loud snort
or gasp. Frequent arousals, although necessary for breathing to restart, prevent the patient from getting enough restorative sleep.
Q: When should sleep apnea be suspected?
A: Bed partners or family members are often the first to suspect that something is wrong, usually from their heavy snoring and apparent
struggle to breathe. Coworkers or friends of the sleep apnea sufferer may notice that the individual falls asleep during the day at
inappropriate times, such as while driving a car, working or talking. The patient may not be aware of the underlying condition, but it is
important that the person see a doctor for evaluation of the sleep problem.
Q: What is a Sleep Study?
A: A sleep study is a test that records a person’s bodily activities while he, or she, is sleeping.
Today, a sleep study is a whole lot easier than it used to be.
For many years, the standard sleep test (called a "polysomnography") required the patient go to a "Sleep Lab" where
technicians used adhesive to apply more than a dozen uncomfortable metal electrodes to the forehead, scalp and body.
In addition, you are videotaped while sleeping as a technician monitors the sensor signals overnight.
Frequently Asked Questions