Obstructive sleep apnea is a disorder in which breathing is briefly and repeatedly interrupted during sleep. The "apnea" in sleep apnea refers to a breathing pause that lasts at least ten seconds. Obstructive sleep apnea occurs when the muscles in the back of the throat fail to keep the airway open, despite efforts to breathe. Another form of sleep apnea is central sleep apnea, in which the brain fails to properly control breathing during sleep. Obstructive sleep apnea is far more common than central sleep apnea.
Obstructive sleep apnea, or simply sleep apnea, can cause fragmented sleep and low blood oxygen levels. For people with sleep apnea, the combination of disturbed sleep and oxygen starvation may lead to hypertension, heart disease and mood and memory problems. Sleep apnea also increases the risk of automobile crashes. Sleep apnea can be life-threatening and you should consult your doctor immediately if you feel you may suffer from it.
More than 18 million American adults have sleep apnea. It is very difficult at present to estimate the prevalence of childhood OSA because of widely varying monitoring techniques, but a minimum prevalence of 2 to 3% is likely, with prevalence as high as 10 to 20% in habitually snoring children. OSA occurs in all age groups and both sexes, but there are a number of factors that increase risk, including having a small upper airway (or large tongue, tonsils or uvula), being overweight, having a recessed chin, small jaw or a large overbite, a large neck size (17 inches or greater in a man, or 16 inches or greater in a woman), smoking and alcohol use, being age 40 or older, and ethnicity (African-Americans, Pacific-Islanders and Hispanics). Also, OSA seems to run in some families, suggesting a possible genetic basis.
Chronic snoring is a strong indicator of sleep apnea and should be evaluated by a health professional. Since people with sleep apnea tend to be sleep deprived, they may suffer from sleeplessness and a wide range of other symptoms such as difficulty concentrating, depression, irritability, sexual dysfunction, learning and memory difficulties, and falling asleep while at work, on the phone, or driving. Left untreated, symptoms of sleep apnea can include disturbed sleep, excessive sleepiness during the day, high blood pressure, heart attack, congestive heart failure, cardiac arrhythmia, stroke or depression.
If you suspect you may have sleep apnea, the first thing to do is see your doctor. Bring with you a record of your sleep, fatigue levels throughout the day, and any other symptoms you might be having. Ask your bed partner if he or she notices that you snore heavily, choke, gasp, or stop breathing during sleep. Be sure to take an updated list of medications, including over the counter medications, with you any time you visit a doctor for the first time. You may want to call your medical insurance provider to find out if a referral is needed for a visit to a sleep center.
One of the most common methods used to diagnose sleep apnea is a sleep study, which may require an overnight stay at a sleep center. The sleep study monitors a variety of functions during sleep including sleep state, eye movement, muscle activity, heart rate, respiratory effort, airflow, and blood oxygen levels. This test is used both to diagnose sleep apnea and to determine its severity. Sometimes, treatment can be started during the first night in the sleep center.
The treatment of choice for obstructive sleep apnea is continuous positive airway pressure device (CPAP). CPAP is a mask that fits over the nose and/or mouth, and gently blows air into the airway to help keep it open during sleep. This method of treatment is highly effective. Using the CPAP as recommended by your doctor is very important.
Second-line methods of treating sleep apnea include dental appliances, which reposition the lower jaw and tongue, and upper airway surgery to remove tissue in the airway. In general, these approaches are most helpful for mild disease or heavy snoring.
Lifestyle changes are effective ways of mitigating symptoms of sleep apnea. Here are some tips that may help reduce apnea severity:
- Lose weight. If you are overweight, this is the most important action you can take to cure your sleep apnea (CPAP only treats it; weight loss can cure it in the overweight person).
- Avoid alcohol; it causes frequent nighttime awakenings, and makes the upper airway breathing muscles relax.
- Quit smoking. Cigarette smoking worsens swelling in the upper airway, making apnea (and snoring) worse.
- Some patients with mild sleep apnea or heavy snoring have fewer breathing problems when they are lying on their sides instead of their backs.
The most important part of treatment for people with OSA is using the CPAP whenever they sleep. The health benefits of this therapy can be enormous, but only if used correctly. If you are having problems adjusting your CPAP or you're experiencing side effects of wearing the appliance, talk to the doctor who prescribed it and ask for assistance.
Getting adequate sleep is essential to maintaining health in OSA patients. If you have symptoms of insomnia such as difficulty falling asleep, staying asleep, or waking up unrefreshed, talk to your doctor about treatment options. Keep in mind that certain store-purchased and prescription sleep aids may impair breathing in OSA patients. One exception is ramelteon, which was studied in mild and moderate OSA patients and found to not harm their breathing.
In the 2005 Sleep in America poll, 8% of respondents experienced or had been observed having pauses in their breathing during sleep at least three nights per week. Adults in the poll were also given the Berlin questionnaire, a standardized test assessing risk for sleep apnea. Based on the quetionnaire, 26% of all poll respondents were at risk. Of those at risk, 70% said that they snored, slept on average 6.4 hours/weeknight (compared to overall mean of 6.8 hours); 66% were experiencing daytime sleepiness at least 3 days per week and over half (58%) were obese. Of adults in this population who had been diagnosed with high blood pressure or depression, almost half were also at risk for sleep apnea. 33% of those who drink 4 or more caffeinated beverages daily are designated at risk for sleep apnea.
Reviewed by Barbara Phillips, M.D., M.S.P.H.