What Causes Obstructive Sleep Apnea?

When you're awake, throat muscles help keep your airway stiff and open so air can flow into your lungs. When you sleep, these muscles are more relaxed. Normally, the relaxed throat muscles don't stop your airway from staying open to allow air into your lungs.

But if you have obstructive sleep apnea, your airways can be blocked or narrowed during sleep because:

  • Your throat muscles and tongue relax more than normal.
  • Your tongue and tonsils (tissue masses in the back of your mouth) are large compared to the opening into your windpipe.
  • Being overweight. The extra soft fat tissue can thicken the wall of the windpipe. This causes the inside opening to narrow and makes it harder to keep open. Although thin people can have sleep apnea to.
  • The shape of your head and neck (bony structure) may cause a smaller airway size in the mouth and throat area.
  • The aging process limits the ability of brain signals to keep your throat muscles stiff during sleep. This makes it more likely that the airway will narrow or collapse.

Not enough air flows into your lungs when your airways are fully or partly blocked during sleep. This can cause loud snoring and a drop in your blood oxygen levels.

When the oxygen drops to dangerous levels, it triggers your brain to disturb your sleep. This helps tighten the upper airway muscles and open your windpipe. Normal breaths then start again, often with a loud snort or choking sound.

The frequent drops in oxygen levels and reduced sleep quality trigger the release of stress hormones. These compounds raise your heart rate and increase your risk for high blood pressure, heart attack, stroke, and irregular heartbeats. The hormones also raise the risk for or worsen heart failure.

Untreated sleep apnea also can lead to changes in how your body uses energy. These changes increase your risk for obesity and diabetes.

Who Is At Risk for Sleep Apnea?

It's estimated that more than 12 million American adults have obstructive sleep apnea. More than half of the people who have this condition are overweight.

Sleep apnea is more common in men. One out of 25 middle-aged men and 1 out of 50 middle-aged women have sleep apnea.

Sleep apnea becomes more common as you get older. At least 1 out of 10 people over the age of 65 has sleep apnea. Women are much more likely to develop sleep apnea after menopause.

African Americans, Hispanics, and Pacific Islanders are more likely to develop sleep apnea than Caucasians.

If someone in your family has sleep apnea, you're more likely to develop it.

People who have small airways in their noses, throats, or mouths also are more likely to have sleep apnea. Smaller airways may be due to the shape of these structures or allergies or other medical conditions that cause congestion in these areas.

Small children often have enlarged tonsil tissues in the throat. This can make them prone to developing sleep apnea.

Other risk factors for sleep apnea include smoking, high blood pressure, and risk factors for stroke or heart failure.

What Are the Signs and Symptoms of Sleep Apnea?

One of the most common signs of obstructive sleep apnea is loud and chronic (ongoing) snoring. Pauses may occur in the snoring. Choking or gasping may follow the pauses.

The snoring usually is loudest when you sleep on your back; it may be less noisy when you turn on your side. Snoring may not happen every night. Over time, the snoring may happen more often and get louder.

You're asleep when the snoring or gasping occurs. You will likely not know that you're having problems breathing or be able to judge how severe the problem is. Your family members or bed partner will often notice these problems before you do.

Not everyone who snores has sleep apnea.

Another common sign of sleep apnea is fighting sleepiness during the day, at work, or while driving. You may find yourself rapidly falling asleep during the quiet moments of the day when you're not active.

Other Signs and Symptoms

Others signs and symptoms of sleep apnea may include:

  • Morning headaches
  • Memory or learning problems and not being able to concentrate
  • Feeling irritable, depressed, or having mood swings or personality changes
  • Urination at night
  • A dry throat when you wake up

In children, sleep apnea can cause hyperactivity, poor school performance, and aggressiveness. Children who have sleep apnea also may have unusual sleeping positions, bedwetting, and may breathe through their mouths instead of their noses during the day.

Breathing Devices

Continuous positive airway pressure (CPAP) is the most common treatment for moderate to severe sleep apnea in adults. A CPAP machine uses a mask that fits over your mouth and nose, or just over your nose. The machine gently blows air into your throat.

The air presses on the wall of your airway. The air pressure is adjusted so that it's just enough to stop the airways from becoming narrowed or blocked during sleep.

Treating sleep apnea may help you stop snoring. But stopping snoring doesn't mean that you no longer have sleep apnea or can stop using CPAP. Sleep apnea will return if CPAP is stopped or not used correctly.

Usually, a technician will come to your home to bring the CPAP equipment. The technician will set up the CPAP machine and adjust it based on your doctor's orders. After the initial setup, you may need to have the CPAP adjusted on occasion for the best results.

CPAP treatment may cause side effects in some people. These side effects include a dry or stuffy nose, irritated skin on your face, sore eyes, and headaches. If your CPAP isn't properly adjusted, you may get stomach bloating and discomfort while wearing the mask.

If you're having trouble with CPAP side effects, work with your sleep specialist, his or her nursing staff, and the CPAP technician. Together, you can take steps to reduce these side effects. These steps include adjusting the CPAP settings or the size/fit of the mask, or adding moisture to the air as it flows through the mask. A nasal spray may relieve a dry, stuffy, or runny nose.

There are many different kinds of CPAP machines and masks. Be sure to tell your doctor if you're not happy with the type you're using. He or she may suggest switching to a different kind that may work better for you.

People who have severe sleep apnea symptoms generally feel much better once they begin treatment with CPAP.

What can I expect during a Sleep Study?

Our sleep studies typically begin at 8:00 p.m. For night shift workers, we will try to schedule your study during your normal sleeping hours. We will explain the procedure and prepare you for the study.

You will spend the night in one of our private rooms as we observe your sleep. If your physician prescribes a sleep aid bring it with you as we are unable to dispense medication. Your study should be done by 8:00 a.m. the next morning (unless you stay for a day study also).

We are equipped to set you up with your therapeutic needs (CPAP, BiPAP, etc). These options will be discussed with you in the morning if the study indicates you qualify for treatment.

After your sleep study is completed, results will be interpreted by a doctor specializing in sleep medicine. You will be given instructions to schedule a post-study follow-up appointment with this doctor to discuss your study results and plan of care.

All of our facilities offer private comfortable rooms with satellite TV. We feature high quality queen-sized beds, including Select Comfort adjustable beds and desks, as well as handicapped accessible bathrooms and showers. In the morning, a free continental breakfast is offered for your convenience. If you need to stay through the next day for additional testing (less than 10% of patients), lunch is also provided.

Because of the possibility of a day study (less than 10% of patients), we ask that you make arrangements to be available for continuous testing the following day if necessary.

Bring comfortable, loose fitting apparel, such as pajamas, to sleep in. We recommend that you bring all your toiletries such as toothbrush, toothpaste, etc. You are also welcome to bring your favorite pillow, blanket, or anything else that helps you sleep.

Informational Videos


Here is a link to the Mayo Clinic Video
that shows what happens during obstructive sleep apena.

Here is a link to the Mayo Clinic video
that shows how CPAP controls Sleep Apnea.


obstructive sleep apnea
CPAP Video

Sleep Center of Central Minnesota
13495 Elder Dr. Suite 120
Baxter, MN 56425
Phone: 218-454-0225
Fax: 218-454-0214