Remember, diagnosing Obstructive Sleep Apnea (OSA) starts with your physician.
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 breath." 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 apneac 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: How is sleep apnea diagnosed?
A: In addition to the primary care physician, ear, nose and throat (ENT) doctors, pulmonologists, neurologists, or other physicians with specialty training in sleep disorders may be involved in making a definitive diagnosis and initiating treatment. Diagnosis of sleep apnea is not simple because there can be many different reasons for disturbed sleep. Several tests are available for evaluating a person for sleep apnea.
Polysomnography is a laboratory procedure that records a variety of body functions during sleep, such as the electrical activity of the brain, eye movement, muscle activity, heart rate, respiratory effort, air flow, and blood oxygen levels. These tests are used both to diagnose sleep apnea and to determine its severity.
Diagnostic tests usually are performed in a sleep disorders center, but new technology now allows some sleep studies to be conducted in the patient's home.
The SSI Web site will give physicians secure access to patient data and enable doctors to track outcomes, build a personal Web site and perform a number of other functions to help build the practice and improve patient care.
Q: How is sleep apnea treated?
A: The specific therapy for sleep apnea is tailored to the individual patient based on medical history, physical examination, and the results of a sleep study. There are currently no effective pharmacological agents available to treat OSA..
Behavioral changes may be all that is needed in mild cases of sleep apnea, including avoidance of alcohol, tobacco, and sleeping pills, which make the airway more likely to collapse during sleep and prolong the apneic periods.. Even a 10 percent weight loss can reduce the number of apneic events for most overweight patients. In some patients with mild sleep apnea, breathing pauses occur only when they sleep on their backs. In such cases, use of pillows and other devices that help them sleep in a side position is often helpful.
Physical or mechanical therapy procedures include nasal continuous positive airway pressure (CPAP), in which the patient wears a mask over the nose during sleep, and air pressure from a pump prevents airway collapse. The air pressure is adjusted so that it is just enough to prevent the throat from collapsing during sleep. Dental appliances that reposition the lower jaw and the tongue have been helpful to some patients with mild sleep apnea or who snore but do not have apnea.
Surgery helps many patients with sleep apnea. Some of the more common procedures include removal of adenoids and tonsils (especially in children), nasal polyps or other growths or tissue in the airway and correction of structural deformities.
There are relatively new procedures that use radio waves to reduce the size of some airway structures, such as the palate and the back of the tongue. Uvulopalatopharyngoplasty (UPPP) and laser-assisted uvulopalatoplasty (LAUP) are other procedures used to remove excess tissue at the back of the throat (tonsils, uvula, and part of the soft palate). Both procedures may decrease or eliminate snoring but not eliminate sleep apnea itself. In severe, life-threatening cases, a tracheostomy may be performed, which involves creating a small hole in the windpipe and inserting a tube into the opening to create an artificial airway. Finally, surgical procedures to treat obesity are sometimes recommended for sleep apnea patients who are morbidly obese.
Q: How large is the market for diagnosing and treating sleep apnea?
A: Sleep disorders represent a growing area of opportunity because there are so many unmet needs in both diagnosis and treatment, according to a survey published by Decision Resources, Inc., a subsidiary of Arthur D. Little, Inc. An estimated 40 million Americans who snore chronically are candidates for a sleep apnea test. Healthcare costs for sleep apnea have been estimated at more than $15 billion. Awareness among physicians about the potentially serious outcomes of OSA has increased over the last several years, however there is still considerable underdiagnosis of sleep apnea.