People who have OSA stop breathing repeatedly during sleep because the airway collapses. This collapse may be due to factors including a large tongue, extra tissue in the airway, or decreased muscle tone holding the airway open. These factors create an obstruction which prevents air from getting into the lungs. This creates "pauses" in breathing known as apnea events. For some, these events can happen 30 times or more per hour. When healthy sleep is interrupted in this way, the risk of developing serious health conditions may increase.