Sleep apnea can occur when breathing is interrupted while sleeping. There are different types of sleep apnea: Central sleep apnea happens when the brain fails to send signals to muscles that control and initiate breathing. Obstructive sleep apnea occurs when throat muscles relax, and air cannot flow in and out through the nose and mouth; this form is more common. Complex sleep apnea syndrome happens when the individual suffers both central and obstructive sleep apnea. The individual may not even be aware that there is a problem, as the body will restart breathing while he or she is still sleeping. This may sound harmless, but it can result in fatigue during the day. In more severe manifestations, sleep apnea is associated with serious illness including, high blood pressure, stroke, and even heart attack.
This potentially serious condition is quite common. In its first description in 1965, this breathing disorder was characterized by short disturbances in breathing while sleeping. In Greek, apnea means "want of breath."
The upper throat muscles of a non-sufferer works to keep the throat open for air flow to the lungs. During sleep, the muscles relax, but the passage remains open for breathing. People with a narrow passage can’t get air into their lungs as muscles relax.
Sleep apnea sufferers may experience 20 to 30 or more involuntary pauses in breathing a night--with some people feeling a choking sensation. While loud snoring and labored breathing accompanies this disorder, not every person who snores suffers sleep apnea.
These interruptions can result in morning headaches and daytime sleepiness, and are associated with high blood pressure, irregular heartbeat, and even stroke or heart attack.
People who snore loudly, who are overweight, who suffer high blood pressure, or have a physical abnormality in the airway are more likely to develop the condition. There may also be a genetic component as well. Some 22 million Americans have this condition, with 80 percent of people, with moderate to severe problems, going undiagnosed. No age bracket goes untouched and both sexes suffer, though more men have the condition than women.
Symptoms of sleep apnea as catalogued by sleepapnea.org:
- Poor sleep
- Loud snoring
- Not breathing for periods (apnea)
- Awakening not rested
- Daytime sleepiness
- Hypersomnia, falling asleep during the day
- Problems staying asleep, insomnia
- Morning headaches
- Weight gain
- Cannot focus attention during daytime
- Memory loss
- Poor judgment
- Personality changes
- Leg swelling for severe apnea
- Rote reactions, automatic behavior
- High blood pressure
A narrow airway or other structural problem may cause difficulty in breathing while sleeping; relaxed tongue and throat muscles can block the airway opening. The muscles of the soft palate at the base of the tongue and the uvula (the fleshy tissue hanging from the center of the back of the throat) relax and sag, thereby blocking the airway. Obesity is also a cause, with tissue narrowing the airway, obstructing airflow through the nose or mouth.
A person who suffers from sleep apnea doesn’t get enough oxygen, but has an excess of carbon dioxide in the blood. This oxygen decrease and carbon dioxide increase nudges the brain to resume breathing, and the brain then signals the upper airway muscles to open. These repeated arousals to get the airway to open results in disturbed sleep patterns—the person doesn’t sleep deeply and experiences daytime fatigue. Other consequences include impaired concentration and cognitive function, irritability, depression, falling asleep during the day, sexual dysfunction, and high blood pressure. Sleep apnea also increases risk for heart attack and stroke. And in some cases, sudden infant death syndrome and sleep apnea have been linked.
Spouses are the first to notice the problem, and co-workers and friends may find the person falling asleep at work or other environments, even while driving. The afflicted individual may be the last to learn of the problem.
The individual will need to see their primary care physician, and in some cases pulmonologists, neurologists, or others with expertise in sleep disorders may be consulted for diagnosis and treatment. Medical history and a physical exam are likely needed.
There can be different reasons for disturbed sleep, making diagnosis of sleep apnea potentially complex. The physician may evaluate the individual through testing, which can be performed in a sleep center. However, there are simplified home sleep tests that measure heart rate, blood oxygen level, airflow, and breathing patterns as well.
The polysomnography test records body function during sleep, including the electrical activity in the brain, muscle activity, heart rate, respiration, airflow, blood oxygen, and eye movement. Such a test should diagnose sleep apnea and determine severity of the problem.
The time it takes for a patient to fall asleep is measured through the multiple sleep latency test. People suffering disturbed sleep take an average of 10 to 20 minutes to fall asleep. This test also measures the degree of excessive daytime sleepiness a person might suffer, and it is useful in ruling out other disorders as well.
In minor cases, encouraging the person to sleep on his or her side might be all that is required. If nasal congestion is a problem, a decongestant may be prescribed. For some people, weight loss may be recommended; even a 10 percent weight loss may alleviate the problem. And in other cases, devices like airway masks can be helpful. The physician may recommend nasal continuous positive airway pressure, known as the nasal CPAP. This mask works with a pump that helps keep the airway open through air pressure.
Sedatives or sleeping pills are never recommended. In general, medication is not effective. Oxygen administration may work for some patients but it doesn’t cure the sleep apnea, and it’s hard to know which patients will respond well. Any treatment should be verified through the polysomnography.
In more extreme cases, surgery may be recommended to correct airway obstruction.
Although several surgical procedures are used to increase the size of the airway, none of them is completely successful or without risks. More than one procedure may need to be tried before the patient realizes any benefits.
Common procedures include removal of adenoids and tonsils, especially in children; nasal polyps, structural deformities, or other growths or tissue obstructing the airway. Younger patients benefit more from these procedures than older patients.
Uvulopalatopharyngoplasty removes excess tissue at the back of the throat (tonsils, uvula, and part of the soft palate). Again, it is hard to predict which patients will respond to this procedure.
Tracheostomy is reserved for life-threatening sleep apnea, but is poorly tolerated by patients and rarely used. A small hole is made in the windpipe and a tube is inserted into the opening. This tube stays closed during waking hours, so the person can breathe and speak. During sleep the hole is opened to bypass the airway obstruction.
For morbidly obese patients, surgery to treat obesity is sometimes recommended.