Obstructive Sleep Apnea (OSA) occurs when your airway temporarily collapses during sleep. You continue to make efforts to breath but are unable to move air in and out of your lungs because of the obstruction at the back of your throat. During the collapse, which can last from 10 seconds to over a minute, your breathing muscles continue to work with a progressive effort until you awaken and resume normal breathing. After a few breaths, your oxygen levels return to normal. You fall back to sleep and the airway obstruction occurs again. This cycle may continue throughout the night, disrupting your normal sleep pattern. As a result, you may complain of un-refreshing sleep and excessive daytime sleepiness.
What is the cycle of Obstructive Sleep Apnea?
The cycle of OSA starts with snoring and continues until the airway collapses or closes off. The person tries to breathe but is unable to get air into their lungs through the collapsed airway and an apnea (cessation of breathing) occurs. The brain realizes that it is not getting enough oxygen and fresh air so it wakes the person from a deep level, to a lighter level, of sleep. The airway then opens and normal breathing resumes. The person falls back into a deeper sleep, begins snoring again and the cycle repeats.
How common is sleep apnea?
- 1 in 15 people have moderate to severe OSA (Young et al. JAMA 2004)
- 9% women and 25% men in the middle-aged working population have OSA (Marshall et al. Sleep 2008)
- Sleep apnea is as common as diabetes and asthma.
- Most OSA sufferers remain undiagnosed and untreated.
- 50% of patients with Type II Diabetes have OSA
- 35% of patients with high blood pressure have OSA 6
What causes the airway to collapse during sleep?
- Extra tissue in the back of the airway such as large tonsils
- Decrease in the tone of the muscles holding the airway open
- The tongue falling back and closing off the airway
- Abnormal anatomy such as a recessed jaw
What are the common signs and symptoms?
For many sleep apnea patients, it is usually their partner or family members that suspect something is wrong. They may complain about their snoring and apparent struggle to breath at night. The typical sleep apnea patient may have the following symptoms:
- Excessive daytime sleepiness (EDS)
- Loud irregular snoring
- Witnessed apneic or choking periods
- Morning headaches
- Frequent awakenings during the night
- Rapid onset of sleep
- Leg cramps
- Weight gain
- Sleepiness while driving
- Frequent need to urinate at night