I, too, wonder if everybody who does a sleep test gets prescribed a CPAP. The test was very uncomfortable. Strap all sorts of wires to a person, tell them to sleep in a room where there are cameras and microphones pointed at them and see if you have normal sleep! When they guy came in to "wake" me at 2AM, I was not sure I even slept. But then he put the CPAP on for the rest of the night and I slept better than I had in years.
I use a ResMed S9 machine with the humidity attachment and 12V cord purchased from cpap.com. I have one 12V battery, an 80 watt solar panel, an LED lights throughout. I have not had a problem with power when boondocking. I think the first night of camping, with the CPAP attached, earplugs on and fresh air all around is when I get some of my best sleep ever.
Back when I was tent camping, my snoring bothered everybody within earshot and my kids complained a lot. I used to struggle trying to power the thing in a tent with all sorts of battery and solar charging contraptions. So being in a truck camper, sleeping on a real bed with my CPAP attached is pure heaven. I agree with others and am very grateful to be able to have this level of comfort while camping. So many others have health issues that are more difficult to deal with.