What is Obstructive Sleep Apnea (OSA)?

Apnea literally means “cessation of breath”. In other words, apnea is when you stop breathing. Obstructive Sleep Apnea (OSA) is simply when your airway becomes obstructed during sleep, causing you to stop breathing. The human upper airway is surrounded by muscles. The largest of these muscles is the tongue. When we are awake we have tightness, or tonicity, in our upper airway muscles, but during sleep these muscles relax.

As we breathe during sleep, the throat and upper airway muscles relax and may begin to vibrate (this vibration is what causes snoring).  Eventually these muscles relax even more and can collapse into the airway, effectively closing your throat and prohibiting air from flowing into your lungs. When you airway collapses and you stop breathing, your body responds as if you are suffocating.  Your brain realizes that you are not receiving oxygen from your lungs, and arouses you from deeper stages of sleep (where rest occurs) to a lighter stage of sleep. By moving to a lighter stage of sleep, your brain is able to contract your throat and upper airways muscles to open your airway and help you resume breathing.  This tightening of your upper airways muscles helps force open your airway which allows air and oxygen to flow into your lungs so you do not suffocate. This cycle of suffocation (apnea) and arousal to breath can happen hundreds of times a night. In most cases you are not fully awake, so you may not even realize this is happening to you every night! Obstructive Sleep Apnea (OSA) can cause excessive daytime sleepiness, mental impairment, cardiovascular problems, heart attack, stroke, diabetes, impotence, acid reflux, and a multitude of other undesirable side effects.  Obstructive Sleep Apnea is a serious and progressive condition that can lead to serious health problems and even death if left untreated.

A 2014 study by the Public Health Agency of Canada estimated 5.4 million Canadian adults have been diagnosed with, or are at high risk of experiencing, obstructive sleep apnea. It is currently 80 per cent under-diagnosed within the population," Low diagnosis rates are attributed, in part, to the nature of the condition: many of the most obvious symptoms, such as snoring and pauses in breathing, happen while people are asleep. Others, like daytime drowsiness, are often brushed off as "normal" tiredness.

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What is Obstructive Sleep Apnea?

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