Obstructive Sleep Apnea
Obstructive sleep apnea is a common sleep disorder. It occurs when tissues in the upper airways come too close to each other during sleep, temporarily blocking the inflow of air.
Who Is At Risk
Obstructive sleep apnea can develop in anyone at any age but most often occurs in people who are:
Sleep Apnea Symptoms
Symptoms of sleep apnea include:
Patients with sleep apnea may find these lifestyle changes helpful:
The treatment of obstructive sleep apnea depends in part on the severity of the condition. Treatment options include:
Obstructive sleep apnea (OSA) is a disorder in which a person temporarily stops breathing during the night, perhaps hundreds of times. These gaps in breathing are called apneas. The word apnea means absence of breath. An obstructive apnea episode is defined as the absence of airflow for at least 10 seconds.
Sleep apnea is usually accompanied by snoring, disturbed sleep, and daytime sleepiness. People might not even know they have the condition.
Obstructive sleep apnea (OSA) occurs when tissues in the upper throat relax and come together during sleep, temporarily blocking the passage of air. In general, OSA occurs as follows:
Obstructive sleep apnea is defined as five or more episodes of apnea or hypopnea per hour of sleep (called apnea-hypopnea index or AHI) in individuals who have excessive daytime sleepiness. Patients with 15 or more episodes of apnea or hypopnea per hour of sleep are considered to have moderate sleep apnea.
All of the muscles in the body relax during sleep. In people without obstructive sleep apnea, the throat muscles relax but do not block the airways. In patients with obstructive sleep apnea, the airways do become temporarily blocked or narrowed during sleep, reducing air pressure and preventing air from flowing normally into the lungs.
Certain physical characteristics of the face, skull, and neck can affect the size of the airway.
Large Neck. A large neck (17 inches or greater in men and 16 inches or greater in women) is a risk factor for sleep apnea. While some people’s necks are naturally larger than others, being overweight or obese can contribute to having a large neck.
Facial and Skull Characteristics. Structural abnormalities in the face and skull contribute to many cases of sleep apnea. These include:
Soft Palate Characteristics. Some people have specific abnormalities in the soft area (palate) at the back of the mouth and throat that may lead to sleep apnea. These abnormalities include:
Muscle Weakness. Abnormalities or weakness in the muscles that surround the airway can also contribute to obstructive sleep apnea.
Sleep apnea occurs in about 2% of children and can occur even in very young children. The most likely causes include:
Obstructive sleep apnea is more common in men than in women. Men tend to have larger necks and weigh more than women. However, women tend to gain weight and develop larger necks after menopause, which increases their risk of developing sleep apnea.
Sleep apnea is most common in adults ages 40 - 60 years old. Middle age is also when symptoms are worse. Nevertheless, sleep apnea can affect people of all ages.
African-Americans face a higher risk for sleep apnea than any other ethnic group in the United States. Other groups at increased risk include Pacific Islanders and Mexicans.
People with a family history of obstructive sleep apnea are at increased risk of developing the condition.
Obesity is a particular risk factor for sleep apnea, even in adolescents and children. Obesity can contribute to sleep apnea when fat deposits fill throat tissue.
Smoking. Smokers are at higher risk for apnea. Those who smoke more than two packs a day have a risk 40 times greater than nonsmokers.
Alcohol. Alcohol use may be associated with apnea. Patients diagnosed with sleep apnea are recommended not to drink alcohol before bedtime.
Diabetes. Diabetes is associated with sleep apnea and snoring. It is not clear if there is an independent relationship between the two conditions or whether obesity is the only common factor.
Gastroesophageal Reflux Disease (GERD). GERD is a condition caused by acid backing up into the esophagus. It is a common cause of heartburn. GERD and sleep apnea often coincide. Research suggests that the backup of stomach acid in GERD may produce spasms in the vocal cords (larynx), thereby blocking the flow of air to the lungs and causing apnea. Apnea itself may also cause pressure changes that trigger GERD. Obesity is common in both conditions, and more research is needed to clarify the association.
Polycystic Ovary Syndrome (PCOS). Obstructive sleep apnea and excessive daytime sleepiness appear to be associated with polycystic ovary syndrome (PCOS), a female endocrine disorder. About half of patients with PCOS also have diabetes. Obesity and diabetes are associated with both sleep apnea and PCOS and may be the common factors.
Sleep apnea can lead to a number of complications, ranging from daytime sleepiness to possible increased risk of death. Sleep apnea has a strong association with several diseases, particularly those related to the heart and circulation.
Daytime sleepiness is the most noticeable, and one of the most serious, complications of sleep apnea. It interferes with mental alertness and quality of life. Daytime sleepiness can also increase the risk for accident-related injuries. Several studies have suggested that people with sleep apnea have two to three times as many car accidents, and five to seven times the risk for multiple accidents. Undertreated sleep apnea is a major risk factor for injury at factory and construction work sites.
Sleep-disordered breathing is very common among patients with heart problems such as high blood pressure, heart failure, stroke, heart attack, and atrial fibrillation. This link may be because both cardiovascular conditions and sleep apnea share a common risk factor of obesity. However, increasing evidence suggests that severe OSA is an independent risk factor that may cause or worsen a number of heart-related conditions.
High Blood Pressure. Moderate-to-severe sleep apnea definitely increases the risk for high blood pressure (hypertension) even when obesity is not a factor. Doctors are not certain whether treating OSA with CPAP reduces the risk for high blood pressure, but studies indicate that CPAP may help prevent or decrease high blood pressure.
Coronary Artery Disease and Heart Attack. Sleep apnea appears to be associated with heart disease regardless of the presence of high blood pressure or other heart risk factors. Studies suggest that patients with moderate-to-severe obstructive sleep apnea have a higher risk for heart attack.
Stroke. Sleep apnea may increase the risk of death in patients who have previously had a stroke.
Heart Failure. Up to a third of patients with heart failure also have sleep apnea. Central sleep apnea often results from heart failure. Obstructive sleep apnea can cause heart damage that worsens heart failure and increases the risk for death.
Atrial Fibrillation. Sleep apnea may be a cause of atrial fibrillation (irregular heartbeat).
Sleep apnea is associated with a higher incidence of many medical conditions, besides heart and circulation. The links between apneas and these conditions are unclear.
Studies report an association between severe apnea and psychological problems. The risk for depression rises with increasing severity of sleep apnea. Sleep-related breathing disorders can also worsen nightmares and post-traumatic stress disorder.
Because sleep apnea so often includes noisy snoring, the condition can adversely affect the sleep quality of the bed partner. Spouses or partners may also suffer from sleeplessness and fatigue. In some cases, the snoring can disrupt relationships. Diagnosis and treatment of sleep apnea in the patient can help eliminate these problems.
Failure to Thrive. Small children with undiagnosed sleep apnea may "fail to thrive," that is, they do not gain weight or grow at a normal rate and they have low levels of growth hormone. In severe cases, this may affect the heart and central nervous system.
Attention Deficits and Hyperactivity. Problems in attention and hyperactivity are common in children with sleep apnea. There is some evidence that such children may be misdiagnosed with attention-deficit hyperactivity disorder. Even children who snore and do not have sleep apnea may be at higher risk for poor concentration.
People with sleep apnea usually do not remember waking during the night.
Symptoms may include:
Sleep apnea occurs in about 2% of children. They may have symptoms that differ from adults, including:
The symptoms of obstructive sleep apnea are not very specific. This means that most people who snore at night or who feel tired during the day probably do not have sleep apnea. Other medical reasons for daytime sleepiness should be considered by your doctor before referral to a sleep center for diagnostic sleep tests. They include:
Symptoms or findings that make the need for evaluation by a sleep specialist include:
If symptoms suggest obstructive sleep apnea or other sleep disorders, further diagnostic testing will be performed. A sleep specialist or sleep disorders center will perform an in-depth medical and sleep history and physical exam. Centers should be accredited by the American Academy of Sleep Medicine.
To help determine the presence of sleep apnea, the doctor will ask the following questions:
To diagnose sleep apnea, the doctor will check for physical indications of sleep apnea, including:
If sleep apnea is not obvious after a physical examination and history, the doctor will need to rule out any other problems. These include sleep disorders (such as narcolepsy, insomnia, or restless legs disorder) or any medical or psychologic conditions (such as chronic fatigue syndrome or depression) that may be causing daytime sleepiness.
Sleep testing is recommended for patients who are considered at high risk for complications of obstructive sleep apnea. These include people who are obese, and those who have heart failure, coronary artery disease, or disturbances in heart rhythm.
Polysomnography is the technical term for an overnight sleep study that involves recording brain waves and other sleep-related activity. Polysomnography involves many measurements and is typically performed at a sleep center.
The patient arrives about 2 hours before bedtime without having made any changes in daily habits. Polysomnography electronically monitors the patient as he or she passes, or fails to pass, through the various sleep stages.
Overnight polysomnography has been the gold standard for diagnosing obstructive sleep apnea in both adults and children. It is very labor-intensive and expensive, however, and also misses snoring-induced arousals. After the diagnosis of sleep apnea is made, the patient must come back to the sleep center for another night in order to have CPAP started (CPAP titration).
Split-night polysomnography is an alternative option to overnight polysomnography. In split-night polysomnography, patients who have been diagnosed with obstructive sleep apnea in the first part of the evening, receive titration for CPAP during the second part of the night.
Diagnostic testing at home with portable monitors may be an option for patients who appear, based on history and physical exam, to have a high likelihood of moderate-to-severe OSA but who do not have other major medical disorders or other sleep disorders, such as narcolepsy.
Portable monitors should only be used if the patient receives a comprehensive sleep evaluation by a board-certified sleep specialist. The monitors use nasal and respiratory sensors to record airflow, respiratory effort, and blood oxygen levels. The patient needs to be educated in how to use them by an experienced sleep technician.
Patients are shown how to use these devices and then sent home. Many of these devices are also capable of titrating CPAP levels (see Treatment section).
Body position greatly affects the number and severity of episodes of obstructive sleep apnea, with at least twice as many apneas occurring in people who lay on their back as in those who sleep on their side. This may be due to the effects of gravity, which cause the throat to narrow when a person lies on the back. (Indeed, astronauts show a marked reduction in apneas and snoring in the weightlessness of space.) Positional sleep apnea affects people of all ages, including young children.
As a first step in dealing with sleep apnea, the patient should simply try rolling over onto the side. Patients who sleep on their backs and have 50 - 80 apneas per hour can sometimes nearly eliminate them when they shift to one side or the other. (Changing positions is less effective the more overweight a person is, but it still helps.)
Here are some suggestions that might help a person maintain a low-risk sleeping position:
All patients with obstructive sleep apnea who are overweight should attempt a weight-reducing program. Weight loss certainly reduces snoring and apnea/hypopnea episodes in many people, sometimes stopping it completely. It also improves sleep and significantly reduces daytime sleepiness.
Treatment for sleep apnea depends on the severity of the problem. Given the data on the long-term complications of sleep apnea, it is important for patients to treat the problem as they would any chronic disease. Simply trying to treat snoring will not treat sleep apnea. Because of its association with heart problems and stroke, sleep apnea that does not respond to lifestyle measures should be treated by a doctor, ideally a sleep disorders specialist.
At this time, the most effective treatments for sleep apnea are devices that deliver slightly pressurized air to keep the throat open during the night. There are a number of such devices available.
The best treatment for obstructive sleep apnea is a system known as continuous positive airflow pressure (CPAP). It is safe and effective for people of all ages, including children. Patients with obstructive sleep apnea who use CPAP feel better rested, have less daytime sleepiness, and have improved concentration and memory. In addition, CPAP may potentially reduce the risks for heart problems such as high blood pressure. For maximum benefit, CPAP should be used for at least 6 - 7 hours each night.
CPAP works in the following way:
The standard CPAP machine delivers a fixed, constant flow of air. Variations on CPAP include:
CPAP works well but it can take some time to get used to, especially for the first few nights. Here are some tips to help you adjust:
In general, drugs are not very helpful except for specific situations. Medications that treat accompanying disorders associated with sleep apnea may be helpful. They include:
Note on Sedatives. Sedatives, narcotics, antidepressants, and anti-anxiety drugs can actually worsen the breathing disturbances and arousal conditions that occur with sleep apnea. These substances cause the soft tissues in the throat to sag and diminish the body's ability to inhale. Apnea sufferers should never use sleeping pills or tranquilizers. Apnea patients undergoing surgery should be sure that their surgeons, anesthesiologists, and other doctors are aware of their sleeping disorder in considering sedatives, anesthetics, and medications taken to relieve pain due to surgery.
Oral appliances, also called dental appliances or devices, may be an option for patients who cannot tolerate CPAP. The American Academy of Sleep Medicine recommends dental devices for patients with mild-to-moderate obstructive sleep apnea who are not appropriate candidates for CPAP or who have not been helped by it. (CPAP should be used for patients with moderate-to-severe sleep apnea whenever possible.)
Several different dental devices are available. A trained dental professional such as a dentist or orthodontist should fit these devices. Devices include:
Patients fitted with one of these devices should have a check-up early on to see if it is working; short-term success usually predicts long-term benefits. It may need to be adjusted or replaced periodically.
Benefits of Dental Devices. Dental devices seem to offer the following benefits:
Disadvantages of Dental Devices. Dental devices are not as effective as CPAP therapy. The cost of these devices tends to be high. Side effects associated with dental devices include:
An orthodontic treatment called rapid maxillary expansion, in which a screw device is temporarily applied to the upper teeth and tightened regularly, may help patients with sleep apnea and a narrow upper jaw. This nonsurgical procedure helps to reduce nasal pressure and improve breathing.
Surgery is sometimes recommended, usually by ear, nose, and throat specialists, for severe obstructive sleep apnea. A patient should be sure to seek a second opinion from a specialist in sleep disorders. Few randomized clinical trials, the gold standard of medical research, have been conducted to verify the long-term efficacy of sleep apnea surgery.
The Procedure. Surgery known as uvulopalatopharyngoplasty (UPPP) removes soft tissue on the back of the throat. Such tissue includes all or part of the uvula (the soft flap of tissue that hangs down at the back of the mouth) and parts of the soft palate and the throat tissue behind it. If tonsils and adenoids are present, they are removed. The surgery typically requires a stay in the hospital.
The Goal of Surgery. The goal of UPPP is threefold:
Success Rates. The American Academy of Sleep Medicine does not endorse UPPP as a sole procedure for treating OSA. The AASM recommends that patients considering this surgery first try CPAP or dental devices.
There is limited evidence as to the effectiveness of UPPP. Studies suggest that success rates for sleep apnea surgery are rarely higher than 65% and often deteriorate with time, averaging about 50% or less over the long term. Few studies have been conducted on which patients make the best candidates. Some studies suggest that surgery is best suited for patients with abnormalities in the soft palate. Results are poor if the problems involve other areas or the full palate. In such cases, CPAP is superior and should always be tried first. Many or most patients with moderate or severe sleep apnea will likely still require CPAP treatment after surgery.
Complications. Uvulopalatopharyngoplasty is among the most painful treatments for sleep apnea, and recovery takes several weeks. The procedure also has a number of potentially serious complications including:
In general, only a small percentage of patients experience serious complications. Many of these complications can be avoided with proper technique and experienced surgeon. A patient's health status, including presence of obesity and other health conditions, may also affect outcomes.
A variation on UPPP called laser-assisted uvulopalatoplasty (LAUP) is being increasingly performed to reduce snoring. It removes less tissue at the back of the throat than UPPP and can be done in a doctor's office. At this time, however, long-term success rates in the treatment of obstructive sleep apnea with LAUP are very modest, particularly for reducing apneas. Some doctors, in fact, are concerned that if LAUP eliminates snoring, they may miss a diagnosis of apnea in patients who have the more serious condition.
More than half of patients complain of throat dryness after surgery. Throat narrowing and scarring have also been reported. In a minority of patients, snoring becomes worse afterward.
According to recent guidelines from the American Academy of Sleep Medicine (AASM), LAUP is not routinely recommended as treatment for obstructive sleep apnea. According to the AASM, this surgery generally does not help improve symptoms and may actually worsen the condition.
The pillar palatal implant is a noninvasive surgical treatment for mild-to-moderate sleep apnea and snoring. However, the main focus of the procedure is a reduction in snoring. The implant helps reduce the vibration and movement of the soft palate. In this procedure, a doctor inserts 3 short pieces of polyester string into the soft palate. The procedure can be performed in a doctor’s office and takes about 10 minutes. Unlike uvulopalatopharyngoplasty (UPPP), the pillar procedure requires only local anesthesia and has less pain and quicker recovery time. There is still not enough evidence to determine whether it is an effective treatment for obstructive sleep apnea.
Tracheostomy used to be the only treatment for sleep apnea. It is quite straightforward:
Today, this operation is performed rarely, usually only if sleep apnea is life threatening.
Other surgical procedures may be appropriate to correct facial abnormalities or obstructions that cause sleep apnea. They may be used alone or combined with each other or with UPPP. Most are invasive and reserved for patients with severe sleep apnea who fail to respond to or comply with CPAP. Overall, there is limited evidence as to their effectiveness in treating OSA. These procedures include:
Adenotonsillectomy, or surgical removal of the tonsils and adenoids, is a first-line treatment for children and adolescents with sleep apnea proven by sleep studies. It cures or improves the condition in most patients.
Complications include respiratory illness, which occurs in about 25% of children after the surgery. The highest risk for respiratory complications is associated with:
The procedure may fail to improve apnea in some patients, such as those with very severe disease. Such children are candidates for continuous positive airway pressure (CPAP) therapy.
Removal of the tonsils and adenoids alone is not an effective treatment for adults with sleep apnea, although the procedure may be effective when combined with UPPP surgery.
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