What Is Sleep Apnea?

Sleep apnea (AP-ne-ah) is a common disorder in which you have one or more pauses in breathing or shallow breaths while you sleep.
Breathing pauses can last from a few seconds to minutes. They may occur 30 times or more an hour. Typically, normal breathing then starts again, sometimes with a loud snort or choking sound.
Sleep apnea usually is a chronic (ongoing) condition that disrupts your sleep. When your breathing pauses or becomes shallow, you’ll often move out of deep sleep and into light sleep.
As a result, the quality of your sleep is poor, which makes you tired during the day. Sleep apnea is a leading cause of excessive daytime sleepiness.

Overview

Sleep apnea often goes undiagnosed. Doctors usually can't detect the condition during routine office visits. Also, no blood test can help diagnose the condition.
Most people who have sleep apnea don't know they have it because it only occurs during sleep. A family member or bed partner might be the first to notice signs of sleep apnea.
The most common type of sleep apnea is obstructive sleep apnea. In this condition, the airway collapses or becomes blocked during sleep. This causes shallow breathing or breathing pauses.
When you try to breathe, any air that squeezes past the blockage can cause loud snoring. Obstructive sleep apnea is more common in people who are overweight, but it can affect anyone. For example, small children who have enlarged tonsil tissues in their throats may have obstructive sleep apnea.
The animation below shows how obstructive sleep apnea occurs. Click the "start" button to play the animation. Written and spoken explanations are provided with each frame. Use the buttons in the lower right corner to pause, restart, or replay the animation, or use the scroll bar below the buttons to move through the frames.

The animation shows how the airway can collapse and block air flow to the lungs, causing sleep apnea.

Central sleep apnea is a less common type of sleep apnea. This disorder occurs if the area of your brain that controls your breathing doesn't send the correct signals to your breathing muscles. As a result, you'll make no effort to breathe for brief periods.
Central sleep apnea can affect anyone. However, it's more common in people who have certain medical conditions or use certain medicines.
Central sleep apnea can occur with obstructive sleep apnea or alone. Snoring typically doesn't happen with central sleep apnea.
This article mainly focuses on obstructive sleep apnea.

Outlook

Untreated sleep apnea can:

Increase the risk of high blood pressure, heart attack, stroke, obesity, and diabetes
Increase the risk of, or worsen, heart failure
Make arrhythmias (ah-RITH-me-ahs), or irregular heartbeats, more likely
Increase the chance of having work-related or driving accidents

Sleep apnea is a chronic condition that requires long-term management. Lifestyle changes, mouthpieces, surgery, and breathing devices can successfully treat sleep apnea in many people.