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Topic Overview
What is sleep apnea?
Sleep apnea is a condition that occurs when you regularly stop breathing for 10 seconds or longer during sleep. It can be classified as mild, moderate, or severe, based on the number of times per hour you stop breathing (apnea) or have slowed breathing (hypopnea). Apnea episodes may occur from 5 to 50 times an hour.
There are three types of sleep apnea: obstructive sleep apnea, central sleep apnea, and mixed sleep apnea. This topic focuses on obstructive sleep apnea.
What causes obstructive sleep apnea?
Obstructive sleep apnea (OSA) usually is caused by a blockage (obstruction) in the nose, mouth, or throat (airway) from a structural problem, such as an enlarged tongue or tonsils. Other factors, such as smoking or obesity, often contribute to OSA. For example, you may have enlarged tonsils that partially block the airway. During the day when you are awake and upright, this may cause no problems. However, when you lie down at night, fatty tissue in the neck can press down on your airway, narrowing it and causing OSA.
See illustrations of normal and blocked airways during sleep.
What are the symptoms of OSA?
The main symptoms of OSA are loud snoring and sleepiness during the day. Your bed partner may notice periods when you stop breathing during sleep. Other symptoms may include:
- Tossing and turning during sleep.
- Feeling suffocated during sleep.
- Feeling tired all the time.
- Morning headaches.
- Feeling irritated and unrested.
- Falling asleep at inappropriate times, such as while eating, driving, or talking.
- Problems on the job.
What happens in OSA?
During an apnea episode, your blood oxygen level may drop because you stop breathing. Over time, low blood oxygen levels can lead to serious health problems and early death. If you have OSA, you may be at increased risk for developing high blood pressure (hypertension), high blood pressure in the lungs (pulmonary hypertension), depression, difficulty with concentration, abnormal heart rate, heart failure, coronary artery disease (CAD), and stroke.
If you have OSA, you may feel tired throughout the day. You may fall asleep at inappropriate times, such as while driving or working, which can lead to a higher-than-average rate of automobile- and work-related accidents.
How is OSA diagnosed?
A medical history and physical examination are the first steps in diagnosing OSA. If these suggest you have this condition, a sleep study (polysomnographic study) is recommended. A sleep study is usually done at a sleep center, where you will spend the night. Sleep studies identify:
- How often you stop breathing or have slower breathing during sleep.
- How low your blood oxygen levels drop during sleep.
- How often your sleep is disturbed and you wake up.
- A number of other tests, such as measuring your eye movement, may also be done during the sleep study.
How is OSA treated?
If you have mild OSA, losing weight, developing good sleep habits, and avoiding alcohol and certain medications may cure the condition. If you have moderate to severe OSA, you may need to use a breathing device (continuous positive airway pressure [CPAP]) that prevents your airway from closing during sleep. If CPAP is not effective, or if enlarged tissues are causing the blockage, surgery may be needed.
