Yes, in theory I have a GP overseeing my care. I have diabetes (my wife as well), so we are seeing him every 3-6 months. My wife asked to have a sleep study done as she was having sleeping issues, and he prescribed one. It was a home study, and came back as severe apnea at about 67 AHI. I was a much more reluctant candidate as I could see what she was going through using a CPAP, and I really didn't want any part of it. I was getting good sleep, and really did not have sleep issues other than I was snoring, and that obviously was bugging my wife. I finally got coerced into completing a questionnaire, and I failed that, so I got the home sleep study prescribed as well. My AHI came back as lower but still severe at 33. The study lab which was the same one for both of us, send the results to the GP recommending a CPAP, and the GP just rubber stamps it.
The way the government health care system works in our area is that the sleep study, and a two week trial of a CPAP, is fully covered at no cost. However the CPAP is not. In both of our cases the sleep study clinic offered to sell us the machines at a cost of $2400 each. After some research I found I could buy them on line for about $900 using the prescription from the sleep clinic, signed by our doctor. So we each bought one, with mine this year, and my wife about 3 years ago. At that price you get limited follow up and monitoring. That is where the do it yourself part comes in. Our GP is of very limited help. I suspect he knows very little about apena other than what it basically is.
That said, I am not complaining. I know people who have insurance and take the deluxe $2400 deal, all paid for by insurance, and I think they get short changed. Their monitoring and followup is minimal to none. They just get an auto machine set with wide min max limits and the machine does its thing. And unless the results are really bad, nothing changes.
When we bought the machine for my wife, the lady we dealt with was good enough to tell us about SleepyHead, and we have used it ever since. I frankly don't know how anyone could effectively monitor and adjust their treatment without it. One the other hand I can also make you a bit obsessive. My one criticism of SleepyHead is that it seems overly harsh on the way it rates leaks. My machine always gives me a happy face, but SleepyHead almost always is very critical. I just ignore it!