Help interpreting Encore Pro / MyEncore data

[Tridens]

Can anyone help interpret my Encore Pro data, which is confusing the snot out of me?

My average AHI, after 2 months treatment, is still around 19. The doc recently increased my pressure from 6-10 to 6-12. At 6-10, I was spending most of my sleep time with the unit pegged at 10. Now that it's at a max of 12, I'm spending much of my time in the 11-12 range.

Here's the weird thing (or weird to a newbie, anyway). Before the doc increased my max press from 10-->12, I spent most of my time at 10 (29% of my sleep time), yet my AHI at 10 was the highest of any pressure (17.3). Ironically, my AHI was lowest at the lowest pressure setting of 6(AHI of 3.7, at 19.7% of the night).

Now that I'm at a max of 12, my AHI at 12 is 28!

So, looking at MyEncore report "Dependance of AHI on Pressure," I have AHI "dips" at 6 (lowest) and 9, and the high points are my two max pressures (originally 10 and later increased to 12).

Adding to the confusion, my snore index LOWERS as the pressures get higher, with 7.5 at 10cm, 4 at 11cm, and only .2 at 12cm (the pressure at which my AHI is highest!). I figured my snore data and AHI data would parallel each other.

I can't make any sense out of this. Is my pressure too high? Still too low? Is the APAP "chasing the needle?" I'd appreciate any help. I'd be happy to send my reports (both Encore Pro and MyEncore) to anybody who thinks they could help. Thanks!

Tridens

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CPAPopedia Keywords Contained In This Post (Click For Definition): newbie, Encore Pro, AHI, APAP

[rested gal]

I think I'd be raising the lower pressure. Perhaps try a narrow range, but with the lower pressure up closer to what your prescribed pressure (if they gave you a single prescribed pressure) is.

Example, if your prescribed pressure is 10, I'd raise the lower pressure up to 8, or even 9 if that pressure doesn't bother you while breathing out or give you aerophagia. Set the upper pressure 3 or 4 notches above the prescribed pressure. See how that goes for a few nights.

I know that most think of the advantage of using autopap as being using a very low pressure most of the night. And autopap does work fine for many set "low". But for some, keeping the lower pressure up close to "titrated" pressure, very near or at it, works better. In that case, there's still an advantage to using autopap since the upper pressure can be set to give ceiling room above the prescribed pressure, in case more is needed for brief times during the night, or things change in the future requiring more anyway.

I don't have Derek's MyEncore, so don't know how the correlations you mentioned go.

[derek]

Tridens,
A couple of points:
1) You have to realize that there can be significant statistical errors in the reported indices when there are not very many hours recorded at each pressure. As you record more hours, the validity of the numbers recorded will increase. You might turn on the error bars in MyEncore, which give a feel for the accuracy of the the AHI vs. Pressure graph.
2) That said, it sounds that you might be in a similar situation as me, where the prescribed pressure was too high. My AHI vs. pressure showed a distinct minimum at 10 cm, while the value at 12 cm (prescription) and higher was much worse. I finally settled on CPAP at 10 cm, and am averaging an AHI of 0.7 at that pressure - which is much better than I was getting using APAP at 9 - 14 cm.
My snore index showed the same behavior as yours, very significant drop off as the pressure increases, until it was virtually 0 at 11 cm. I can not determine any correlation between the occurence of snores in my data with hypopneas or apneas. When I do have the occasioanl snore episode there is no sign of apneic activity. I really question the supposed relationship between snores and apneas. You probably know that Respironics make snores the highest priority event for raising the pressure in APAP. In my case snoring simply raised the pressure, which made me more likely to have hypopneas/apneas...

My recommendation: do an experiment and stick with your apap settings for a few weeks to let the long term data trends in the pressure graphs develop. Then reassess the situation, and discuss it with your doc. It may well be that you will receive better treatment at a lower pressure like me.

Derek

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[jdacal]

Derek is right. I am a heavy snorer. With the CPAP I still have "inaudible" snores, or maybe barely inaudible I should say, that the machine still picks up.

As a result no matter how high the pressure is set the machine tends to go up to that maximum pressure.

So what I've had to do is lower the high pressure one step at a time over many weeks until I found that 15 is ideal for me and 11 for the low. The machine stays at 15 a lot, but it does occasionally come down to 11 when my snoring goes away for some periods.

My AHI is steadily at 3.1 and I can probably lower it more with a few more tweaks.

Derek is right about another thing. I've been taking two weeks of readings before each change I make. If you make changes with just a few days of data you won't get very far in finding ideal pressures.

Oh, one other thing, putting the CFLEX at its max pressure seemed to reduce the snoring for me. Once I find ideal pressures I may try easing up on the CFLEX and see what happens.

[SnoreNoMore2005]

I just installed Derek's Myencore pro. I think that is terrific of Derek to write a program and make it available to end-user for free! The world needs more people like Derek.

Here's my question:

I see on the preference screen that it says MyEncore contains data only from 7/26/05. However, the EncorePro database goes back to 7/14/05. I tried changing the dates, etc., to no avail. The MyEncore will only display data from 7/26/05 forward.

Am I doing something wrong?

Thank you

SnoreNoMore2005