false AHI??

Please help a newbie understand AHI
my AHI average was over 50 per hour during the sleep study
I have been on an auto bipap bi-flex machine for one week with a full face mask
a ramp pressure of 4 that goes up to 8 after 5 minutes
my top possible pressure is 25...though the machine says I've only gone up to 12
the doctor thought I would need a higher pressure...I did in the sleep study
supposedly 0% leaks
the first few days I was at 3.9 AHI
after a week it reads 5.2 AHI for both the 7 day average and 30 day average
can coughing or taking the mask off while the machine is still running result in a higher AHI?
how about hitting the ramp button several times throughout the night?
thanks

machine- Repironics bipap auto bi-flex
with humidifier set on 3
ResMed Mirage Quattro full face mask
ramp set on 4...ramps up to 8
pressure from 8 to 25

taking the mask off while the machine is still running will impact the leaks... which in turn impacts the AHI... so yes on that one.

I disagree, the machine "knows" when you take the mask off. When I wash my mask and tube, I use the machine to blow air through and dry the tubing. If you look on Encore Viewer software, that time during which the air was blowing unopposed shows up as a black line and no AHI's are recorded. The ramp should not affect it, the coughing is unlikely to be the issue unless it's a LOT of coughing.

The problem you have is that you are relying on the LED screen for data and it's not enough to make any conclusions. The screen reports ONLY 7 and 30 day averages. So you could have had one bad night and skewed the 7 day average. And it shows only average large leaks. Well, think about it--if you sleep 8 hours a night for 7 days, that's 56 hours X 60 minutes = 3,360 minutes (no guarantees my math is correct, I'm a math dweeb). To register only a 1% "large leak" you have to be leaking like a jet plane for 34 minutes.

Only with the software can you see what's really going on and what might be contributing to your sudden increase in AHI.