Your doctor has a reasonable rationale, but my doctor disagrees. Is it possible to have the same results every single night? This is unlikely, as sleep conditions change with positions, how big a meal one ate, how one is feeling (e.g. sinus congestion), etc. If you post your data, I am sure you have SOME events, but they may be variable from one night to another. My doctor says that this is why autopaps respond better to the changing needs of sleep from one night to another. In his opinion, and he's very experienced in sleep disorders, sleep is a fluid situation, which varies from night to night. Unless you build a wall around yourself in bed, eventually you will end up on your back sometime, and there goes a change in AHI right there, and in pressure needs. I bet that with your vigilance, you have a good titration, but it it perfect? No, as it is subject to change every night.My sleep doc explained to me that she didn't like APAP because it REQUIRES apnea events to work. It starts out at a level known to be too low to catch all events, then bumps up as events occur to an effective level. Once no events are occurring, it backs off until they do. And the cycle repeats throughout the night, allowing totally unnecessary events to occur.
There is a huge advantage, if an individual is subject to spikes in pressure that are intermittent, and variable. I am one such person, and occasionally, I will get a spike of a 11 or 12, even once a 13 on a 'bad night." If I were set at my 95% pressure (that is 9.5), those occasional spikes would not be treated, and I'd have apneas that are not being chased, but ignored completely. A lot of folks on this board seem to get variability and spikes on a given night,I understand the argument that it changes pressure in response to needs, thereby providing a lower average pressure. But, unless you are subject to pressure-indued centrals, I don't see any real advantage there. And, as has been said, some people are bothered by the constant pressure changes.
Your position is known and understood, and clearly, you're following your doctor's advice. My doctor gave me the opposite advice, as situationally, the structure of my sleep isn't so regular that one set pressure can prevent all apneas. Also, the comfort factor of having my pressure for 95% of the night at a lower number, and still achieve successful therapy is important to me. I do feel rested, and have a fairly low AHI (normally 1-2), and few apneas, with an occasional hypopnea that my machine successfully catches and treats. For you, obviously a fixed pressure seems to work better. For many of us, it doesn't, as our sleep isn't as uniform as yours seems to be. You're lucky that a fixed pressure catches all events, but I am skeptical about that---it would be logical that there would be some night to night variances.With the concurrence of my doc, I normally use CPAP at my 90% pressure. Every 6 months or so (sooner if I feel any change), I do a week on APAP to confirm my 90% hasn't changed. I rarely have an AHI higher than 1.0...and my AI is 0 about 30% of the time (meaning my AHI is mostly hypopneas). I have far more apneas during my "self-titration" week on APAP than I normally have on CPAP, which is why I do that so rarely. It just seems to me that any apnea I prevent is a good thing, as the results are cumulative.
I also understand some get better numbers on APAP. I've never heard any explanation how that could happen, but I'll take their word for it.
