Long-time APAP user, having trouble with formerly successful settings

[Pando]

I've recently started APAP therapy after a hiatus.

A few years ago I discovered I had a wheat allergy that was causing a large amount of inflammation in my airway, making it very difficult to breathe each night. Despite this, APAP therapy was able to give me restful sleep and I was a productive member of society. After cutting wheat out of my diet I was able to breathe fine and my chronic fatigue was mostly gone, so I discontinued APAP therapy, which in hindsight was unwise.

Around six months ago my chronic fatigue returned, and has gotten significantly worse since. I've reacquired my Phillips Dreamstation and have restarted my APAP therapy.

The old settings (Auto pressure 5.5/12, A-Flex 3) worked great for me before, but don't seem to anymore. I'm definitely getting better sleep, but not nearly well enough, as my fatigue and brain fog are so bad that most days I can only work 1-2 hours or none at all. This is severely affecting my ability to do even basic tasks.

Settings I've tried:

-Pressure 6.50/9.00, A-Flex 3
-Pressure 5.50/7.00-9.00-12.00, A-Flex 3


Having the pressure at 6.50 felt a little overwhelming, but it was manageable. I tried 7.0 for a few minutes and even with A-Flex at 3 I felt the pressure was trying to stuff air into my lungs and keep it there-- exhaling was very difficult. I definitely slept worse with minimum pressure at 6.50 which worries me, as this limits my range of effective treatment. I have a hunch that the lower quality sleep may be due to positional apnea, though a few years ago I was able to keep my AHI consistently below 5.0 whether sleeping on my back or side.

I've attached screenshots of a day from a few years ago along with most of my recent days of treatment (I forgot to put my SD card back into my machine for a few of them so I don't have flow rate data, I left those days out)

A few years ago:
   

This week:
   
   

More data uploaded to this Imgur album: https://imgur.com/a/eECkFVN


Thank you for your time, I very much appreciate it

[Pando]

I may have been correct regarding the positional apnea, the past few nights I've made a conscious effort to prevent chin tucking while keeping my neck/spine aligned and it seems to have made a difference.

Another factor may have been frequent arousals, so I did what I could to block light from my window. Last night was the best night of sleep I've gotten in the ten or so days I've had my machine, 3.94 AHI and I feel mostly rested. Still room to improve but I feel like I can function today, I'm over the moon. It's been miserable living with chronic brain fog and fatigue and for the first time in half a year I almost feel normal