1 month of CPAP and my AHIs are all over the place

[Zzzer]

So I'm 20+ days into my therapy. I use a straight CPAP, 7 pressure and get about 6.5 hours of sleep a night with it. I feel somewhat better throughout the day, but nothing miraculous. The mask does not bother much at all, except when I have an itch on my face, under my mask.

My main concern is my AHI readings. My average AHI over this period is 6.0, with a low of 1.1 and a high of 12. I've read where the ResMed Elite is not as accurate at reporting AHI as an actual sleep study, but I'm not sure. My reported leak rates have been minimal and only showed up on 3 nights of usage.

Just as background, my 1st sleep study reported my AHI at 40.1, so I guess even though my current AHI is around 6, I guess this is an improvement. However, everything I read says AHI under CPAP therapy should be below 5.

So, is this something I should be concerned about? Should my Dr. raise my CPAP pressure?

Thanks.

[BlackSpinner]

So, is this something I should be concerned about? Should my Dr. raise my CPAP pressure?

Yes. Properly treated OSA is well under 5AHI.

[Pugsy]

Could you please post an image of a couple of detailed nightly reports? Don't know how? We talked about it here in this thread.
viewtopic.php?f=1&t=81072&p=737779#p737779

Should you increase the pressure? No, not until you understand what you are trying to fix. If your higher AHI nights are predominantly central in nature then increasing the pressure won't help and might actually make things worse.

Check out the top thread in the Announcements section of this forum main page for the thread for understanding your data.

[Zzzer]

Thanks, I will try to post some data this evening, when I get home from work.

[BobHale]

Zzzer,

I would not worry about AHIs all over the place for a while yet. I had the same issue for the first few months. I had a lot of centrals that eventually went away. Your body needs to adjust to the treatment.
For me there was no sudden change in how I felt. I did feel better gradually. I have been using CPAP for 3 years now and will not go back to how I felt before.
Avoid getting over involved with the numbers. I tried all kinds of things to get my leak numbers below 30. Eventually I discovered it was not compromising my sleep. It may be hard on my machine but I hated the chinstrap and mouth pieces I tried.

Bob H

[Zzzer]

Thanks Bob. That is really good to hear. I'm glad you've had a positive experience. I hope to get there eventually.

[idamtnboy]

+1 for what Pugsy says. Getting your therapy regimen optimized is not an overnite job (pun intended)! You really need to look at your data over a several week period to get the big picture as to what is happening. Then you can start making changes slowly. We recommend that you change only one parameter at a time, and then wait at least a week to see if the results are different. As for AHI, I liken it to a kid on a trampoline, it will go up and down, usually somewhat randomly without identifiable cause.

[Zzzer]

So here's some data on 3 of my bad nights. This is my first shot at Photobucket, so I hope it works.

[JeffL]

Based on my unprofessional, but personal experience, I'd say it's too early to worry about it.

This was my AHI during my first 4 months in 2011 (high and all over the place):


This is the same time period a year later:

[Pugsy]

You have some significant clustering of hyponeas or obstructive apneas and then periods of time with nothing of any great excitement going on.
The 2 main factors that we normally think about when we see clusters is either sleep position (supine) or REM stage sleep because it is common for apnea events that occur in either to need more pressure.
If you have copies of your sleep studies you might spot which one might be what you are experiencing...or you might have a combination of both supine sleep and REM stage sleep being a factor.

Normally the first REM stage sleep will occur about 90 minutes or so after sleep onset. You have some clusters that appear pretty much right after sleep onset so I wouldn't think REM in that situation but it wouldn't be impossible.
If you never sleep on your back then it's probably REM stage sleep. Especially the latter clusters that happen in the wee hours of the morning because that's when we typically have more REM stage sleep.

We have some control over sleeping position but we don't over REM stage sleep. We don't want to prevent REM sleep anyway.

So for some reason it appears that you sometimes need a little more pressure to prevent the collapse of the airway. Since your clusters are primarily obstructive in nature and not central then a little more pressure to prevent the clustering or break up the clusters would be something to consider.

The clusters are large and significant enough that I would be trying to break them up if it were me.

The night's where your AHI doesn't reflect the clusters and is nice and low...if your clusters are related to sleep position maybe you simply stayed on your side more...or maybe if REM related your sleep was shorter hours or maybe fragmented so that you didn't get as much REM stage sleep...maybe both.

So I think that a little more pressure is indeed indicated. This is where it would be nice if you had auto adjusting capabilities so that the machine only has to use more pressure when needed but your pressure isn't horribly high now so a little more pressure all night long is unlikely to present much of a problem unless you have some aerophagia issues with it.
If you choose to increase your pressure I would go up slowly and give the setting several nights so you can make sure you have a good representation of your sleep patterns. It may only take a small change to break up the clusters or make them much smaller and less frequent. I still get a few clusters every now and then with my current set up but they are small and infrequent so I don't worry about them. In my situation my OSA is much worse in REM stage sleep and almost all clusters I might see are in a time frame where I would expect to be in REM sleep. I had clusters similar to yours initially...large and frequent. Now they are smaller and fairly infrequent.

[Zzzer]

Jeff, Pugsy:

Thanks so much for your replies.

Jeff,

Did you make any adjustments (I.e. pressure, mask, machine-type) to see those kind of improvements, or did it just take time?

Pugsy,

I really appreciate your analysis of my data. I'm going to my sleep Doc next week for my first follow up since using CPAP. I'm not expecting much. All his office asked for was my compliance data, to confirm my hours of use. I doubt he will even consider an auto PAP for my treatment. I hope he's at least open to upping my pressure a bit to break up my clusters.

I noticed you didn't address my AHI. Is the AHI only a summary statistic that doesn't identify underlying issues?

Thx again.

[Pugsy]

I noticed you didn't address my AHI. Is the AHI only a summary statistic that doesn't identify underlying issues?

The AHI goes along with the clusters. Periods of times with nothing going on and then short periods of time where there were large numbers of events.
Even if the AHI had been technically a bit under 5.0 with the bulk of the events in clusters like you see...I would still want to break up the clusters.
The clusters actually bother me more than the AHI of 8 something.
If you zoom in on one of those clusters you will see lots of events coming more or less back to back. That's a lot more stressful on the body than when they happen alone and randomly.