What causes Sleep apnea?
OSA is caused by the relaxation of the muscles of the back of the throat, which then impede airflow. Normally, the muscles of the upper part of the throat help keep the airway open and allow air to flow into the lungs. Even though these muscles usually relax during sleep, the upper throat should remain open wide enough to let air pass through unobstructed.
Several factors may affect the width of the throat area, and can therefore contribute to the obstruction of the airway. Having a narrower throat area can affect the ease with which air can pass through the airways. When the muscles in the narrower upper throat relax during sleep, the airway may completely close. This prevents air from getting into the lungs and loud snoring and labored breathing occur. During deep sleep, breathing can stop for a period of time (often more than 10 seconds). This is called apnea. </s>