There is essentially a continuous normal distribution of "apneic" sleep features. There is no bright line between apnea and not apnea, though we create lines fo

There is essentially a continuous normal distribution of "apneic" sleep features. There is no bright line between apnea and not apnea, though we create lines for simplicity's sake. Of course if you need CPAP, use CPAP. But there are plenty of people who have soft tissue that closes off the upper airway to a significant degree only when supine. These are the people who don't need to deal with the modest but non-zero risks associated with respiratory assistance — all by just sleeping in a different position.