AHI of 7 at 10 months on CPAP - When, how to push for better

I was referred for a sleep study last summer due to having low waking O2 sats, horrible sleeping O2 desats, as well as starting to have issues with my blood pressure. It was a good catch on the Physician Assistant's part, because I was diagnosed with severe OSA, with an AHI of 48 (REM 68, NREM 40). Despite those ugly numbers, my Epworth sleepiness score wasn't that bad, but I've never had that rested sleep experience in my life.

After dealing with scheduling a titration study, then dealing with Apria to get my equipment, I started CPAP the end of September. My initial mask was a Mirage Quattro and I tolerated it well. I adjusted to the treatment and was able to sleep with mask for a full night, consistently, within two weeks. Within 2 months my apneas were consistently well controlled, I now have between 0-2 on any given night (not per hour).

However, my hypopneas, although they've improved slightly over time, are still at an average AHI of 7.5.

About a month ago I switched to a Mirage Liberty hybrid mask, and my 95% leak rate has greatly improved. I found I needed to drop my pressure down from 13.8 to 13.2 (and yes, I can tell at that increment). I haven't used EPR for about 6 months now. I still get "farts" from the mouth seal, but they're usually pretty short-lived. And I'm so excited with the nasal pillow therapy - not only am I much more able to breathe through my nose than I ever dreamed, but several areas of long-term irritation on my septum have cleared up. (I had septoplasty and turbinate reduction done many years ago, which helped, but not nearly as much as the CPAP!)

My blood pressure is much better, in fact it's a little on the low side now. My sleeping O2 sats are almost in normal range. (I live at 7200 feet so there is some altitude impact.) My waking O2 sats are still slightly problematic, but that may or may not be improved with CPAP treatment. (Google "Obesity hypoventilation syndrome CPAP" if you're curious.)

However, I'm still not waking with that refreshed feeling I've longed for my whole life.

My questions are (1) How long should I wait to see if the AHI continues to slowly improve? I'd definitely like to see it average under 5. But I'm not seeing any trending improvement in quite some time now. And (2) what are some avenues for improvement that should be explored?

My primary physician has sleep apnea himself, but confessed to me that he only uses it about 4 hours a night - !!!!. I heard a similar story from the tech at the sleep center - !!!! The doc who read my initial study is a neurologist - I had been to him before for an unrelated problem, my fiance has seen him, and he's an arrogant jerk, so I won't see him for this.

My primary physician is fine with my research and open to whatever I suggest to him - very impressed with my compliance, that I have the software, and my own O2 monitor and software. Obviously I'd prefer a competent sleep doc, and I may find one a little further from home, but I need to be prepared in any case.

Thanks in advance for any input you may have.

The Resmed S8 counts hypopneas higher than some other machines. Some here have said to half your hypopneas, if you are using an S8, for a truer picture.

You are doing well with the apneas in the range you stated so, with this quirk of the S8, you are doing very well. Are you going to bed and getting up at about the same time every night? Are you not eating or drinking within a few hours of bedtime? Are you using the machine humidifier, if so, at what setting? Are you on medication for other conditions? Do you have other medical conditions that might be an issue.

Just the things that come to my mind to check into.

I wouldn't worry...I'm in similar situation with similar machine, similar AHI readings after 7 months of therapy. Hawthorne is right about Hi numbers, I don't pay a lot of attention to them.

If you Ai numbers are low, your leaks under control, and getting solid oxygen numbers....all should be fine. How do you feel after initial months of therapy?

If you have the ResScan 3.7 or 3.1 software, download your data and post a couple of images....

mreewh wrote:(1) How long should I wait to see if the AHI continues to slowly improve? I'd definitely like to see it average under 5. But I'm not seeing any trending improvement in quite some time now.

You should usually wait at least a week when changing settings as you will get a variant night on night.

mreewh wrote:(2) what are some avenues for improvement that should be explored?

Usually if the AHI is high then it usually means one of two things that either your leak rate is high, or that your Apnea or Hypopneas are high. If you have access to detailed minute per minute data then you should check that and see at what pressure your Hypopneas are hitting and what your pressure is. WIth an APAP you can see what the pressure increases to and this then that gives you a good indication to what you might want to set the pressure to. Around 13 sounds a little high. You don't mention whether you are on APAP or CPAP. If on CPAP this could be why you're hypopneas are running away because with an APAP you get the best of both worlds, you get the ability to set the minimum pressure and also a maximum pressure, so breath by breath if the machine then realises that you're hitting into trouble, e.g. a hypopnea, then it will gradually start to ramp up the pressure to not only try to reduce the amount of time you're in a hypopnea but it will keep the pressure at that rate for a while, which keeps other hypopneas at bay.

Ultimately you should be looking to get your AHI below 5 to be in the safe zone, although strictly speaking 7 isn't far off. I used to be around 4.5 for 3.5 years until I got the S9 and now I'm at <1. Majority of mine are hypopneas rather than apneas.

It looks like you have the S8 Elite II, I don't think this is an auto machine, so you might want to consider at some point trying an auto machine, like the S9. That way you get not only an Auto machine that allows you to run it in auto mode, or CPAP mode, but you also can read second by second reports on your PC and examine them fully yourself.

Hope that helps.

Thanks
Dave