If you have sleep apnea, go get yourself a damn CPAP machine and wear it when you sleep. Sleep apnea is almost, but not quite, as bad as never even sleeping. That means dozing off during every quiet moment of the day, having waking hallucinations, waking up just as tired as you felt when you went to bed, even sleeping all weekend. Your concentration and mental abilities end up just plain shot. I've known two people with sleep apnea and they both turned their lives around considerably when they had it treated.
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.
