Snoring can certainly be annoying and can be normal. I want to focus this week on a condition that can be associated with snoring - sleep apnea.

Sleep apnea is a condition where people have pauses in their breathing while sleeping. Most people have pauses to some degree, but people with sleep apnea have much longer pauses, sometimes up to 30 seconds. These long pauses cause the level of oxygen in the blood to drop and carbon dioxide to rise. This change in oxygen and carbon dioxide can be very hard on the body, especially the heart and lungs.

There are two main types of sleep apnea - central and obstructive. Central sleep apnea is a problem with the brainstem that sends signals to the breathing muscles. It is not a very common cause of sleep apnea in adults; obstructive sleep apnea (OSA) is seen much more often.

Obstructive sleep apnea is caused by any type of obstruction to the flow of air in and out of the lungs. This usually occurs in the back of the throat when excess or loose tissue collapses into the throat when the muscles relax during sleep. This is why OSA is much more common in obese individuals - they have a lot of extra tissue in their throats that can result in a blockage.

When I see people in my office with a concern about OSA, it is usually at the request of a spouse or significant other who is either tired of listening to the snoring or who has actually seen the patient stop breathing during sleep. They often describe a cycle of snoring respirations, followed by long pauses, then gasping for air. The snoring results from vibrations of the tissue in the back of the throat, quite similar to the vibrations of a guitar or piano string.

There are other signs and symptoms we ask about when evaluating people for OSA. Sleep apnea sufferers are unable to get into a deep sleep - the apneas sometimes wake them tens or even hundreds of times per night. This can result in excessive daytime sleepiness and problems with falling asleep at work or school, while driving, etc. Patients frequently complain of fatigue, irritability, dry mouth, poor concentration and headaches. They may have hypertension or other heart or lung diseases. They often consume caffeine or other stimulants to try to stay awake during the day.

The diagnosis of sleep apnea is suggested by the above history, but in order to confirm the diagnosis a sleep study or polysomnogram must be performed. This has historically been done in a sleep lab where the patient is connected to monitoring equipment that records respirations, brain wave activity, movements via a video camera and gas exchange in and out of the lungs. In-home portable sleep studies can be done as well. All of the sleep study data is collected, summarized or "scored," and interpreted by a physician who has received special training in sleep disorders.

There are very specific scoring criteria a patient must meet to be diagnosed with OSA. Treatment usually involves a device called a CPAP (Continuous Positive Airway Pressure) machine that is connected to a mask on the face. The machine blows air into the patient's airway to prevent the tissues from collapsing when sleeping.

If you feel you may have sleep apnea or know someone who does, you should see a physician to discuss testing. OSA is a very serious condition that can lead to or worsen cardiovascular, lung and neurologic problems. For more information see http://tinyurl.com/4ch2ch.