What is sleep apnea?
Sleep apnea means that your breathing often is blocked or partly blocked during sleep. The problem can be mild to severe, based on how often your lungs don't get enough air. This may happen from 5 to more than 50 times an hour.
This topic focuses on obstructive sleep apnea, which is the most common type.
A less common type of apnea, called central sleep apnea, can occur in people who have had a stroke, have heart failure, or have a brain tumor or infection. Even though this topic isn't about central sleep apnea, some of the treatments discussed here may also help treat it. Talk with your doctor to find out more about central sleep apnea.
What causes obstructive sleep apnea?
Blocked or narrowed airways in your nose, mouth, or throat can cause sleep apnea. Your airway can become blocked when your throat muscles and tongue relax during sleep.
Sleep apnea can also occur if you have large tonsils or adenoids or a large uvula . During the day, when you are awake and standing up, these may not cause problems. But when you lie down at night, they can press down on your airway, narrowing it and causing sleep apnea. Sleep apnea can also occur if you have a problem with your jawbone.
In children, the main cause of sleep apnea is large tonsils or adenoids.
Sleep apnea is more likely to occur if you are overweight, use certain medicines or alcohol before bed, or sleep on your back.
What are the symptoms?
The main symptoms of sleep apnea that you may notice are:
- Not feeling rested after a night's sleep.
- Feeling sleepy during the day.
- Waking up with a headache.
Your bed partner may notice that while you sleep:
- You stop breathing.
- You often snore loudly.
- You gasp or choke.
- You toss and turn.
Children who have sleep apnea:
- Nearly always snore.
- May be hyperactive or have problems paying attention during the day.
- May be restless during sleep and wake up often. They also may have problems with bed-wetting.
But children may not seem very sleepy during the day (a key symptom in adults). The only symptom of sleep apnea in some children may be that they do not grow as quickly as most children their age.
Can sleep apnea cause other problems?
If you have sleep apnea, you may not be sleeping as well as you could. And you may be more likely to end up with serious problems such as:
- High blood pressure .
- High blood pressure in your lungs .
- An abnormal heart rhythm , heart failure , coronary artery disease (CAD) , or stroke .
- Depression .
- Diabetes .
How is sleep apnea diagnosed?
Your doctor will probably examine you and ask about your past health. He or she may also ask you or your sleep partner about your snoring and sleep behavior and how tired you feel during the day.
Your doctor may suggest a sleep study . A sleep study usually takes place at a sleep center, where you will spend the night. Sleep studies find out how often you stop breathing or have too little air flowing into your lungs during sleep. They also find out how much oxygen you have in your blood during sleep. You may have blood tests and X-rays.
How is it treated?
You may be able to treat mild sleep apnea by making changes in how you live and the way you sleep. For example:
- Lose weight if you are overweight.
- Sleep on your side and not your back.
- Avoid alcohol and medicines such as sedatives before bed.
If lifestyle changes don't help sleep apnea, you may be able to use an oral breathing device or other types of devices. These devices help keep your airway open while you sleep.
Sleep apnea is often treated with a machine that helps you breathe while you sleep. This treatment is called continuous positive airway pressure , or CPAP (say "SEE-pap"). Sometimes medicine that helps you stay awake during the day may be used along with CPAP. If your tonsils, adenoids, uvula, or other tissues are blocking your airway, your doctor may suggest surgery to open your airway.
Frequently asked questions
Learning about obstructive sleep apnea (OSA):
Living with sleep apnea:
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Obstructive sleep apnea usually occurs when the throat muscles and tongue relax during sleep and partially or completely block the airway . When you stop breathing or have reduced flow of air into your lungs during sleep, the amount of oxygen in your blood decreases briefly.
Bone deformities, enlarged tissues
Obstructive sleep apnea can also occur if you have bone deformities or enlarged tissues in your nose, mouth, or throat. For example, you may have enlarged tonsils . During the day when you are awake and standing up, this may not cause problems. But when you lie down at night, the tonsils can press down on your airway, narrowing it and causing sleep apnea.
In children, the main cause of sleep apnea is large tonsils or adenoids .
Other things that may contribute to sleep apnea include:
- Drinking alcohol, which affects the part of the brain that controls breathing. This may relax the breathing muscles and cause a narrowing of the airway and sleep apnea.
- Obesity . Fat in the neck area can press down on the tissues around the airways. This narrows the airways and can cause sleep apnea. About 7 out of 10 people who have sleep apnea are obese. 1
- Some medicines that are taken for conditions such as allergies, long-term pain, insomnia, or anxiety. These medicines, such as narcotics , can also relax the muscles and tissues in the throat, causing it to narrow.
With sleep apnea , there are symptoms that you may notice and symptoms that others may notice when you're asleep.
Symptoms you may notice include:
- Excessive daytime sleepiness.
- Waking with an unrefreshed feeling after sleep, having problems with memory and concentration, feeling tired, and experiencing personality changes.
- Morning or night headaches. About half of all people with sleep apnea report headaches. 2
- Heartburn or a sour taste in the mouth at night.
- Swelling of the legs.
- Getting up during the night to urinate.
- Sweating and chest pain while you are sleeping.
Symptoms others may notice include:
- Episodes of not breathing (apnea), which may occur as few as 5 times an hour (mild apnea) to more than 50 times an hour (severe apnea). How many episodes you have determines how severe your sleep apnea is.
- Loud snoring. Almost all people who have sleep apnea snore. But not all people who snore have sleep apnea.
- Restless tossing and turning during sleep.
- Nighttime choking or gasping spells.
Symptoms in children
Children who have sleep apnea nearly always snore. But they may not appear to be excessively sleepy during the day (a key symptom in adults).
In children younger than 5, other symptoms include:
- Mouth breathing.
- Waking up a lot.
In children 5 years and older, other symptoms include:
- Bed wetting.
- Doing poorly in school.
- Not growing as quickly as they should for their age. This may be the only symptom in some children. These children may also have behavior problems and a short attention span.
Other conditions with symptoms similar to sleep apnea include other sleep disorders and an underactive thyroid.
Obstructive sleep apnea causes your airway to narrow or close off, reducing or stopping breathing for short periods during sleep.
If your breathing stops, you may make grunting, gasping, or snorting sounds and restless body movements. As breathing resumes, loud snoring starts. This may happen many times during a night.
The more often it happens, the more severe your sleep apnea is. Sleep apnea is called either mild, moderate, or severe.
When you stop breathing, the oxygen levels in your blood go down and carbon dioxide levels go up. This makes your heart and blood vessels work harder and can affect your heart rate and nervous system. That in turn may:
- Lead to other problems, such as high blood pressure and heart disease.
- Make these other problems worse and harder to treat.
- Raise your risk of having a stroke. 3
Because sleep apnea disturbs your sleep, it can make you very tired during the day. So if you have sleep apnea, you may:
- Be more likely to have a car accident.
- Do poorly at school or work and have trouble concentrating.
- Have memory problems.
- Have personality changes, anxiety, and depression.
- Lose the desire for sex.
What Increases Your Risk
Certain things make it more or less likely that you will have obstructive sleep apnea. Some of these you cannot change, while others you can.
Things you can't change
- Aging. Sleep apnea is most common in people age 30 and older.
- Being male. Sleep apnea is more common in men. 1
- Family history. If other members of your family have sleep apnea, you are more likely to have it than someone who doesn't have a family history of it.
- Ethnicity. Blacks, Hispanics, and Pacific Islanders have a greater risk of sleep apnea than whites. Blacks get sleep apnea at a younger age than whites. 1
- Deformities of the spine. Deformities of the spine, such as scoliosis , may interfere with breathing and contribute to sleep apnea.
- Conditions that may cause head and face abnormalities. Conditions such as Marfan's syndrome and Down syndrome may result in abnormalities and increase the risk for sleep apnea.
- Menopause. Recent studies show that sleep apnea occurs more often in women who have been through menopause than in women who have not. 1 After menopause, women get sleep apnea at a rate similar to men. 2 Experts don't know why or how menopause increases the risk of sleep apnea.
Things you may be able to change
- Obesity. About 7 out of 10 people who have sleep apnea are obese . 1 Obesity is the factor most likely to lead to sleep apnea.
- Neck circumference. People who are overweight may have extra tissue around their neck, adding to their risk for sleep apnea. The risk increases for a man whose neck measures more than 17 inches around and for a woman whose neck measures more than 16 inches around.
- Enlarged tissues of the nose, mouth, or throat. Enlarged tissues in the nose, mouth, or throat can block your airway while you sleep, making sleep apnea more likely. Surgery can sometimes correct the blockage and improve sleep apnea.
- Bone deformities. Bone deformities of the nose, mouth, or throat can interfere with breathing, causing sleep apnea. Some people who have sleep apnea have a small, receding jaw. Surgery can sometimes correct these deformities and improve sleep apnea.
- Use of alcohol or medicine. Drinking alcohol or taking certain medicines before going to sleep can increase the risk for sleep apnea. Medicines include sleeping pills and sedatives .
- Sleeping on your back and using pillows. Sleeping on your back and using one or more pillows may make sleep apnea worse.
- Smoking. Smoking can increase your risk for sleep apnea, because the nicotine in tobacco relaxes the muscles that keep the airways open.
- Poor sleep habits. For example, going to bed in different places may increase your risk for sleep apnea.
- Disorders of the hormone (endocrine) system. Disorders that may increase your risk include hypothyroidism and acromegaly .
When To Call a Doctor
Call your doctor if:
- You or your bed partner snores loudly and heavily and feels sleepy during the day.
- You notice that your bed partner stops breathing, gasps, or chokes during sleep.
- You sometimes fall asleep at inappropriate times, such as while you are talking or eating.
- Your child snores, has trouble breathing while sleeping, sleeps restlessly, wakes up often, and is very sleepy during the day.
Watchful waiting is a wait-and-see approach. If you get better on your own, you will not need treatment. If you get worse, you and your doctor will decide what to do next. Watchful waiting may be right for you if you snore but are not excessively sleepy during the day.
Watchful waiting may not be right if you notice that your sleep partner snores loudly and heavily, is restless during sleep, and is sleepy during the day. If you think your sleep partner may have periods when breathing stops, suggest that he or she talk with a doctor.
Who to see
Health professionals who can check people who have symptoms of obstructive sleep apnea include:
- Family medicine physicians .
- Internists .
- Sleep disorders specialists .
- Pediatricians .
- Nurse practitioners .
- Physician assistants .
Other health professionals may be able to help you if you have other problems that are caused by sleep apnea. If you:
- Have heart problems, you may see a cardiologist .
- Need surgery to remove excess tissue or to correct a defect or injury, you may see an ear, nose, and throat doctor (otolaryngologist) .
- Need oral breathing devices, you may see a dentist .
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
Your doctor will examine you and ask you and possibly your sleep partner some questions about your lifestyle, snoring, sleep behavior, and how tired you feel during the day (this is called a medical history).
Your doctor may ask you to complete a questionnaire, such as the Epworth Sleepiness Scale. The answers to questions in this questionnaire can help the doctor find out if you have sleep apnea. If your doctor thinks that you may have sleep apnea, he or she may suggest sleep studies or other tests.
- Sleep studies are a series of tests that record what happens to your body during sleep. The most important test for sleep apnea is polysomnography. This test records electrical activity of your brain, eye movement, muscle activity, heart rate, breathing, airflow through your nose and mouth, and blood oxygen levels ( saturation ). Polysomnography is the only sure way to find out whether you have sleep apnea.
Other tests that you may have include:
- Blood tests to check for hypothyroidism (TSH test) or a high red blood cell count (complete blood count).
- Electrocardiogram (EKG, ECG) or echocardiogram to see if sleep apnea has affected your heart.
Diagnosing sleep apnea in children
Most doctors follow these guidelines from the American Academy of Pediatrics: 4
- During a routine checkup, your doctor will ask you and your child about snoring. If your child snores, be sure to tell your doctor.
- A complete sleep study typically is needed to find out if your child has sleep apnea and is not just snoring.
- Children who have sleep apnea should see a specialist if they also have:
Testing after initial treatment
To see how well your treatment is working, you may need sleep tests after treatment begins.
If your sleep apnea has not improved after initial treatment, and if enlarged tissues in your mouth and throat are causing it, your doctor may do one or more tests before suggesting surgery to remove the excess tissue. These tests may include:
- Fiber-optic pharyngoscopy , to see whether your airway is too narrow or collapses during breathing.
- CT scan of the head to look for an overly large tongue and excessive soft tissue in the neck, as well as to locate the narrowest part of your airway.
- X-rays . A cephalometric X-ray is a type of head X-ray that allows your doctor to see bone deformities of the skull. This type of X-ray test may not be available in every hospital.
Treatment for obstructive sleep apnea may include:
- Lifestyle changes, such as losing weight. For more information, see Home Treatment.
- Continuous positive airway pressure (CPAP) . For more information, see Other Treatment.
- Oral breathing devices that you wear at night.
- Nasal disks that attach to the outside of your nose and may help keep your airways open while you sleep.
- Medicine to help you stay awake during the day. For more information, see Medications.
- Surgery. For more information, see Surgery.
Your doctor will probably have you try lifestyle changes and CPAP first. Surgery might be a first choice only if the sleep apnea is caused by a blockage that is easily fixed.
You may need to be treated for other health problems before you are treated for sleep apnea. For example:
- People who also have inflammation of the nasal passages ( rhinitis ) may need to use nose spray to reduce the inflammation.
- People who have an underactive thyroid gland ( hypothyroidism ) need to take thyroid medicine.
If your sleep apnea gets worse, talk to your doctor:
- You may need another complete sleep study.
- You may need to adjust your CPAP machine.
- You may be able to take medicine to help you stay awake during the day.
- You may need treatment for problems that sleep apnea may cause, such as high blood pressure.
Treatment for children
Children have the same treatment options as adults. But surgery (removing tonsils or adenoids) typically is the first choice, because enlarged tonsils or adenoids cause most cases of sleep apnea in children. If surgery isn't possible or doesn't work, children are treated using CPAP.
You can help prevent obstructive sleep apnea if you:
- Don't use alcohol and medicines, such as sleeping pills and sedatives , before bed. These can relax your throat muscles and slow your breathing.
- Eat sensibly, exercise, and stay at a healthy weight.
- Quit smoking. The nicotine in tobacco relaxes the muscles that keep the airways open. If you don't smoke, those muscles are less likely to collapse at night and narrow the airways.
Home treatment for obstructive sleep apnea includes lifestyle changes and changing some sleeping habits.
- Lose weight. Some studies have shown that losing weight reduces the number of times an hour that you stop breathing (apnea) or that the airflow to your lungs is reduced (hypopnea). 5, 6 Experts agree that weight loss should be part of managing sleep apnea. 6 If you are overweight and have sleep apnea, nutritional counseling may help.
- Limit the use of alcohol and medicine. Drinking excessive amounts of alcohol or taking certain medicines, especially sleeping pills or sedatives , before sleep may make symptoms worse.
- Get plenty of sleep. Apnea episodes may be more frequent when you have not had enough sleep.
- Quit smoking. The nicotine in tobacco relaxes the muscles that keep the airways open. If you don't smoke, those muscles are less likely to collapse at night and narrow the airways.
- Promptly treat breathing problems, such as a stuffy nose caused by a cold or allergies.
Sleeping habit changes
- Sleep on your side. Try this: Sew a pocket in the middle of the back of your pajama top, put a tennis ball into the pocket, and stitch it shut. This will help keep you from sleeping on your back. Sleeping on your side may eliminate mild sleep apnea. 7
- Raise the head of your bed 4 in. (10 cm) to 6 in. (15 cm) by putting bricks under the legs of the bed. You can also use a special pillow (called a cervical pillow) when you sleep. A cervical pillow can help your head stay in a position that reduces sleep apnea. Using regular pillows to raise your head and upper body won't work.
- Use your CPAP machine every night. If you are using a continuous positive airway pressure (CPAP) machine to help you breathe, use it every night. If you don't use it all night, every night, your symptoms will return right away. For more information about CPAP, see Other Treatment.
Some people use nasal strips, which widen the nostrils and improve airflow. Although these strips may decrease snoring, they cannot treat sleep apnea.
Doctors typically don't suggest using medicines to treat obstructive sleep apnea.
But medicine can help reduce daytime sleepiness when continuous positive airway pressure (CPAP) is reducing the number of times you stop breathing at night but you still feel sleepy during the day. 8, 9
People with sleep apnea who take these medicines to reduce daytime sleepiness should keep using CPAP to treat sleep apnea.
Surgery for obstructive sleep apnea usually isn't done unless other treatments have failed or you are unable or choose not to use other treatments.
- Uvulopalatopharyngoplasty (UPPP). This is the most common surgery to treat sleep apnea in adults.
- Tonsillectomy and/or adenoidectomy. This is often the first treatment option for children, because enlarged tonsils and adenoids are usually the cause of their sleep apnea.
- Tracheostomy. Although this is effective at treating sleep apnea, it is done only when other treatments have failed or when treatment is needed right away.
- Maxillo-mandibular advancement (MMA). This moves the upper and lower jaw forward to increase the size of the airway.
- Radiofrequency ablation (RFA). This reduces the size of the tongue and other tissues that may be blocking airflow to the lungs.
- Palatal implants. These are small plastic rods that are implanted in the soft palate . They make the soft palate stiffer to keep the tissue from blocking the airway.
- Other surgical procedures to repair bone and tissue problems in the mouth and throat.
- Bariatric surgery . This surgery can promote weight loss that improves sleep apnea. 10
What to think about
If you are thinking about having surgery to treat sleep apnea, talk with your doctor about having a sleep study done first.
Experts typically suggest that you try continuous positive airway pressure (CPAP) before considering surgery.
Laser-assisted uvulopalatoplasty uses a laser to perform surgery. It is sometimes used to treat mild to moderate sleep apnea, although not all people benefit. This surgery is not recommended by the American Academy of Sleep Medicine to treat sleep apnea. 11, 12
Continuous positive airway pressure (CPAP)
CPAP is nearly always the first medical treatment for sleep apnea. With CPAP, you use a breathing device that prevents your airways from closing during sleep.
Research shows that:
- CPAP decreases daytime sleepiness, especially in people who have moderate to severe sleep apnea. 13, 6 If you still feel sleepy during the day while using CPAP at night, tell your doctor.
- CPAP can lower daytime and nighttime blood pressure. 14
It may take time for you to be comfortable using CPAP. You may find that you want to take off the mask, or you may find it hard to sleep. If you can't get used to CPAP, talk to your doctor. You might be able to try another type of mask or make other adjustments.
Some CPAP devices automatically adjust air pressure or use different air pressures when you breathe in or out. They are easier and more comfortable for some people to use.
If you use CPAP to treat sleep apnea, you need to use it every night. If you don't use it, your symptoms will return right away.
If CPAP isn't working, you may need another sleep study to find out whether your CPAP machine needs to be adjusted. You may also need to think about surgery.
Oral breathing devices
Oral breathing devices reposition your tongue and jaw during sleep, which opens up your airways. They may be used for people who have mild to moderate sleep apnea. They may also be used for people with severe sleep apnea who try CPAP but find out that it does not work for them.
The U.S. Food and Drug Administration has approved nasal disks for treating sleep apnea and snoring. The disks attach to the outside of your nose. One disk is attached over each nostril. A valve positioned over the nostril makes it harder to breathe out, which causes a little back-pressure in the airways. This back-pressure may help keep the airways open during sleep.
Other Places To Get Help
|National Institute of Neurological Disorders and Stroke|
|NIH Neurological Institute|
|P.O. Box 5801|
|Bethesda, MD 20824|
The National Institute of Neurological Disorders and Stroke (NINDS), a part of the National Institutes of Health, is the leading U.S. federal government agency supporting research on brain and nervous system disorders. It provides the public with educational materials and information about these disorders.
|American College of Physicians|
|190 North Independence Mall West|
|Philadelphia, PA 19106-1572|
The American College of Physicians (ACP) is a national organization of internists. Doctors of internal medicine focus on adult medicine and have had special study and training focusing on the prevention and treatment of adult diseases. The ACP provides information for patients and families on the organization's website, including information on diseases and conditions, end-of-life care, women's issues, and immunizations. The site also offers video news stories, health tips, special reports, and a link to the ACP diabetes webpage.
|American Sleep Apnea Association (ASAA)|
|1424 K Street NW|
|Washington, DC 20005|
The American Sleep Apnea Association provides education and support for people who have sleep apnea.
|National Heart, Lung, and Blood Institute (NHLBI)|
|P.O. Box 30105|
|Bethesda, MD 20824-0105|
The U.S. National Heart, Lung, and Blood Institute (NHLBI) information center offers information and publications about preventing and treating:
|National Sleep Foundation|
|1010 North Glebe Road|
|Arlington, VA 22201|
The National Sleep Foundation, an independent nonprofit organization, can provide you with brochures on sleep disorders and a list of accredited sleep disorder clinics.
- Malhotra A, White DP (2002). Obstructive sleep apnea. Lancet, 360(9328): 237–245.
- Guilleminault C, Abad VC (2004). Obstructive sleep apnea syndromes. Medical Clinics of North America, 88(3): 611–630.
- Arzt M, et al. (2005). Association of sleep-disordered breathing and the occurrence of stroke. American Journal of Respiratory and Clinical Care Medicine, 172(11): 1447–1451.
- American Academy of Pediatrics (2002). Clinical practice guideline: Diagnosis and management of childhood obstructive sleep apnea. Pediatrics, 109(4): 704–712.
- Johansson K, et al. (2009). Effect of a very low energy diet on moderate and severe obstructive sleep apnoea in obese men: A randomised controlled trial. BMJ. Published online December 3, 2009 (doi:10.1136/bmj.b4609).
- Hensley M, Ray C (2008). Sleep apnoea, search date May 2008. Online version of BMJ Clinical Evidence : http://www.clinicalevidence.com.
- Silverberg DS, et al. (2002). Treating obstructive sleep apnea improves essential hypertension and quality of life. American Family Physician, 65(2): 229–236.
- Schwartz JRL, et al. (2003). Modafinil as adjunct therapy for daytime sleepiness in obstructive sleep apnea: A 12-week, open-label study. Chest, 124(6): 2192–2199.
- Hirshkowitz M, et al. (2007). Adjunct armodafinil improves wakefulness and memory in obstructive sleep apnea/hypopnea syndrome. Respiratory Medicine, 101(3): 616–627.
- Buchwald H, et al. (2004). Bariatric surgery: A systematic review and meta-analysis. JAMA, 292(14): 1724–1737.
- Aurora RN, et al. (2010). Practice parameters for the surgical modifications of the upper airway for obstructive sleep apnea in adults. Sleep, 33(10): 1408–1413.
- Littner M, et al. (2001). Practice parameters for the use of laser-assisted uvulopalatoplasty: An update for 2000. Sleep, 24(5): 603–619.
- Giles TL, et al. (2006). Continuous positive airways pressure for obstructive sleep apnoea in adults. Cochrane Database of Systematic Reviews (3).
- Norman D, et al. (2006). Effects of continuous positive airway pressure versus supplemental oxygen on 24-hour ambulatory blood pressure. Hypertension, 47(5): 840–845.
Other Works Consulted
- Collop NA, et al. (2007). Clinical guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. Journal of Clinical Sleep Medicine, 3(7): 737–747.
- Kushida CA, et al. (2006). Practice parameters for the indications for polysomnography and related procedures: An update for 2005. Sleep, 28(4): 499–521.
- Kushida CA, et al. (2006). Practice parameters for the treatment of snoring and obstructive sleep apnea with oral appliances: An update for 2005. Sleep, 29(2): 240–243.
- Kushida CA, et al. (2006). Practice parameters for the use of continuous and bilevel positive airway pressure devices to treat adult patients with sleep-related breathing disorders. Sleep, 29(3): 375–380.
- Kushida CA, et al. (2008). Clinical guidelines for the manual titration of positive airway pressure in patients with obstructive sleep apnea. Journal of Clinical Sleep Medicine, 4(2): 151–171.
- Marcus CL, et al. (2012). Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome, Pediatrics, 130(3): e714–e755.
- Morgenthaler TI, et al. (2006). Practice parameters for the medical therapy of obstructive sleep apnea. Sleep, 29(8): 1031–1035.
|Primary Medical Reviewer||Anne C. Poinier, MD - Internal Medicine|
|Specialist Medical Reviewer||Mark A. Rasmus, MD - Pulmonology, Critical Care Medicine, Sleep Medicine|
|Last Revised||January 20, 2012|
Last Revised: January 20, 2012
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