Introduction
Many people demonstrate some degree of difficulty breathing during sleep. At the milder end of the spectrum is snoring , which is simply noisy breathing during sleep. Almost everyone has at least one friend or family member whose snoring can keep the whole house up all night! At the other end of the spectrum is obstructive sleep apnea , in which people snore loudly, but also experience interruptions in their breathing, sometimes occurring even hundreds of times throughout the night. Although people with sleep apnea are often made aware of their problem by family members or friends who complain about their snoring, most are not aware that they may actually have a more severe problem. People with sleep apnea may constantly feel tired during the daytime, and are at increased risk of motor vehicle accidents and work-related injuries. In addition, people with sleep apnea are at higher risk of having high blood pressure, heart disease, and stroke.
Sleep Apnea and Snoring in Depth
What is sleep apnea? Apnea is a pause in breathing lasting for at least 10 seconds. Sleep apnea, which is apnea limited to the time of sleep, can be divided into two main types. Central sleep apnea refers to pauses in breathing during which there is no effort to breathe. In other words, there is no signal from the brain to tell the lungs to breathe. Obstructive sleep apnea refers to pauses in breathing during which there is effort to breathe. The lungs are attempting to draw air into the chest, however due to a blockage or obstruction somewhere along the airway, or breathing passage, there is no airflow. This tends to be more common than central apnea. With both types of events, the apnea eventually results in an arousal, or transition from a deep sleep to a lighter sleep. Upon moving to a lighter stage of sleep, a point is reached where either the airway opens or the brain finally sends the proper signal to the lungs, and breathing resumes. Usually there is no awareness of the periods of apnea or the arousals they cause. However, the restful quality of sleep is disturbed, and a person might awaken after a full 8 or more hours of sleep feeling tired.
What is snoring?
Most people probably know at least one person who snores. It could be a bed partner, a parent, a grandparent, or even a child. Snoring is a noise produced when an individual breathes during sleep. Primary snoring, also known as simple snoring or benign snoring is characterized by loud upper airway breathing sounds during sleep without episodes of apnea. Unfortunately, it is difficult to separate the "simple snorers" from those with sleep apnea. Most people who snore but do not have sleep apnea have no difficulty with insomnia or daytime sleepiness, and are not noted to stop breathing by their bed-partners. If obstructive sleep apnea is suspected, an evaluation by a sleep specialist is needed.
What causes snoring and obstructive sleep apnea?
The airway starts at the nose and mouth, extends through the throat, voice box, windpipe, and finally leads into the lungs. Whereas the windpipe is a relatively non-collapsible passage, the upper portions of the airway are not. During sleep in particular, the muscles that keep the airway open relax, leading to airway collapse. Since the lungs are trying to inhale the same amount of air through a smaller passage, airflow must speed up. Faster airflow sets the flexible structures of the throat, such as the roof of the mouth, or palate, and tongue into vibration, which leads to the annoying sounds of snoring. If the collapse of the airway is complete, airflow stops and apnea occurs. Obstructive Sleep Apnea Syndrome (OSA) is characterized by repetitive episodes of airway obstruction that occur during sleep, usually associated with a reduction in blood oxygen level, and leading to daytime sleepiness.
The airway can be obstructed at any point from the nose to the voice box, although in most cases there are partial obstructions at several levels. The nose can be blocked by a deviated septum, inflammation from allergies, or weakness of the cartilages that support the nose. Enlarged tonsils or a large tongue may block the mouth and throat. The size and shape of the jaw may also play a role by limiting the space in which the tongue and tonsils must fit. The more restricted the airway is when a person is awake, the more likely it is there will be airway obstruction during sleep.
Other factors contribute to the development of apnea, or to its severity. Any type of muscle relaxant, such as alcohol consumed before bedtime or sleeping pills, can increase the degree of airway collapse and worsen snoring or apnea. Weight gain or obesity lead to increase in size of the fat deposits along the throat, which can worsen apnea. Smoking can lead to larger drops in blood oxygen during apnea, which places additional strain on the heart and lungs.
What are the signs and symptoms of sleep apnea?
Most patients with sleep apnea demonstrate loud snoring. However every person who snores does not necessarily suffer from sleep apnea. Often a spouse or bed-partner will notice breathing pauses and alert a person to the possibility of apnea. Some people awaken at times with their heart pounding, sweating, or with the sensation of choking. The poor sleep quality that results from OSA leads one to awaken feeling non-refreshed and having trouble staying awake during the day. This can result in morning headaches, poor concentration, impaired memory, and reduced performance at work.
Is this a serious condition?
YES! Sleep Apnea is a potentially life-threatening condition that requires medical attention. Although patients are mostly bothered by the symptoms listed above, repetitive interruptions of breathing during sleep places excess strain on the heart and lungs. The risks of undiagnosed and untreated obstructive sleep apnea include heart attack, stroke, irregular heartbeat, high blood pressure and heart disease. In addition, obstructive sleep apnea causes daytime sleepiness that can result in lost productivity at work and interpersonal relationship problems. Sleep deprivation such as that caused by sleep apnea has a similar effect on one's ability to drive an automobile as alcohol consumption. People with sleep apnea are roughly seven times more likely to have automobile accidents as those without. People whose sleep apnea is untreated have also been shown to have higher mortality rates than people who have their sleep apnea successfully treated.
How can a doctor tell if I have obstructive sleep apnea or if I just snore?
A history and physical examination in the office may help identify patients at risk for OSA. Typical signs and symptoms of sleep apnea may be identified, and potential sites of airway obstruction determined. However diagnosis of sleep apnea requires a sleep study, also called a polysomnogram. There are two kinds of polysomnogram. A standard overnight study requires an overnight stay in a specialized sleep laboratory. During the test you will sleep in a room similar to a hotel room, while brain waves (EEG), muscle tension, eye movements, cardiogram (EKG), respiration, blood oxygen level, and breathing sounds (snoring, gasping, etc.) are continuously monitored. This allows detection of breathing pauses, determines how often these events occur, indicates whether the breathing pauses are central or obstructive apneas, and shows the effects of these episodes on sleep and the heart and lungs. The second kind of sleep study is a home test. These allow for monitoring some of the body functions recorded in a full sleep lab test, but do so in the patient's normal home sleep environment. A sleep technologist or nurse instructs you on the use of the monitoring equipment, which is then taken home and returned after the test night. Home tests are typically not as sensitive as laboratory sleep tests, and may not detect sleep disorders other than sleep apnea, but are useful in some situations. Both types of tests are painless, and are usually covered by insurance. Sleep apnea is a progressive condition that gets worse as you age. Patients with mild sleep apnea should be evaluated periodically to detect worsening of the disease.
How is sleep apnea treated?
Treatment of sleep apnea depends on the severity of the problem and the patient's airway anatomy. Mild sleep apnea may be adequately treated by behavioral changes. Losing weight will almost always help lessen the severity of snoring or sleep apnea. In people with severe sleep apnea due to obesity in whom dietary changes and exercise alone are not successful in achieving weight loss, surgical treatment may help. Weight loss surgery consists of "stomach stapling," or gastric bypass surgery, which allows one to reduce their food intake and lose weight. Other simple therapies such as sleeping on your stomach or side and reducing alcohol or sleeping pill usage may also help in mild cases. There are specialized devices available through a dentist, called mandibular advancement devices, that keep the airway open that may help snoring or mild sleep apnea. These devices work by holding the jaw in such a position that prevents the airway from collapsing. Such devices may be covered by insurance. In some cases, if mild apnea appears to be a result of an easily remedied blockage of the airway, such as enlarged tonsils or a deviated septum, surgery may provide rapid relief.
In most cases, the first treatment recommended for sleep apnea is Continuous Positive Airway Pressure, or "CPAP." CPAP is a machine that gently pressurizes the air in your airway, preventing the airway from collapsing and becoming blocked. A mask is worn over the nose during sleep that is connected to the CPAP machine (see diagram below). The precise level of pressure delivered by the machine must be determined during a sleep study performed while using the device. Your sleep doctor will "prescribe" the proper pressure setting for the CPAP device. A home healthcare company will set the device to the proper pressure and provide training in its use and maintenance. CPAP is extremely effective for those people who use it properly. It is also one of the lowest risk treatments available.
CPAP mask in use -
the "+" marks show the air under gentle pressure holding the breathing passage open |
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In patients who are unable to use CPAP effectively, surgery may be recommended. Usually a surgeon will ask the patient to be on CPAP for at least month to see if they get better. It is important to note that the results of surgery will very rarely if ever be better than those of CPAP. In other words, if a person uses CPAP but still feels tired in the daytime, it is unlikely that surgery will eliminate the tiredness. Other causes of fatigue may be present, and further medical tests may be necessary.
Surgical treatments are directed at those portions of the airway that are felt to contribute to obstruction. The main areas considered are the nasal passages, the palate and tonsil area, and the back portion of the tongue. Straightening a deviated septum, removing nasal polyps or adenoids, or treating allergies may enlarge the nasal passages. Additional airway space may be gained in the palate area by trimming back an elongated, redundant palate (palatoplasty) or removing the tonsils. The airway space behind the tongue may be widened either by reducing the size of the tongue, or repositioning the tongue further forward in the mouth and throat. Success rates for most surgical procedures vary depending on the particular patient's anatomy and the severity of their apnea.
In very severe cases, or those in whom other surgical treatments have failed, more drastic measures may be required. Moving both the upper and lower jaws forward can dramatically enlarge the airway. This is a complex procedure usually performed by an oral and maxillofacial surgeon, but can be effective in up to 90 % of patients. Lastly, the portions of the airway causing the blockage can be bypassed by placing a tracheotomy tube in the lower neck. This is a breathing tube that is placed through the skin, directly into the windpipe, in the operating room. The tube is usually kept plugged in the daytime so a person can talk and breathe normally. At night the tube is kept open such that an airway is maintained at all times. A tracheotomy tube requires diligent care and cleaning while it is in place, and restricts some activities such as swimming.
What can be done about snoring?
Prior to treatment of snoring, it is usually necessary to rule out obstructive sleep apnea or other sleep disorders. Although this usually requires a sleep study, some patients with minimal symptoms or evidence of airway obstruction on physical examination may be safely treated without. Behavioral and lifestyle changes, such as weight loss, sleeping on your stomach or side, or reducing alcohol intake may be recommended. The dental devices discussed above for treatment of sleep apnea may also reduce or eliminate snoring.
Surgical procedures for the treatment of snoring are generally directed at the roof of the mouth (palate) and uvula, which cause the sounds of snoring in most people who snore. Some procedures involve trimming back some of the excess tissue of the palate and uvula. This can be done under local or general anesthesia, and may be performed with cautery (electric knife) or laser (this procedure is called L aser A ssisted U vulo- P alatoplasty, or LAUP). Newer treatments aim to stiffen, rather than remove these tissues. This is usually done with a radiofrequency device (Somnoplasty). This procedure uses a special needle that passes electric current to heat, and gently burn small areas in the roof of the mouth. As these areas heal, small areas of scarring develop that stiffen the palate, reducing its ability to vibrate, and thus reducing snoring. This procedure is performed in the office under local anesthesia. In general Somnoplasty causes far less discomfort than trimming the palate or uvula, but may need more than one treatment before an acceptable result is achieved.
Your doctor can discuss what treatment options might be best for you following your examination. As simple snoring has thus far not been shown to have long-term effects on health, treatments of snoring are generally not covered by insurance.
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