Why is my AHI high ?

[downsize]

I could really use some help ... I have had my AHI hovering around 28 for the several nights I have been checking it lately. As an experiment, I upped my pressure by 2 and then another 2 on the next night, but my AHI stays the same. My machine is showing almost zero leaking is happening.
I do not have access to a sleep study at this time ... What are the things that could be causing these high AHI numbers ? Thanks

[quietmorning]

Have you changed anything in your sleep routine? (Head pillow, blankets, mattress, number of hours sleeping, etc.)

My numbers are high too right now, but there have been a lot of changes due to the cold I had a couple of weeks ago - so I'm having to do trials with each change (like an allergy trial) to see what on earth bumped my numbers up so high.

[BlackSpinner]

You are probably mouth breathing. Try a full face mask or taping your mouth to eliminate that possibility.
Then try upping your pressure some more.

Or maybe you could rent an APAP from your DME for a week?

[Emilia]

Your machine is data capable, however, it needs a special card reader in order to import the data into the software you install on your computer. The card readers are very hard to come by since your machine is an old model. That said, your DME should be able to read the card for you and give you a report. Do you use a local DME that can do that for you? If so, call and ask if you can bring in your machine for a reading and tell them about your very high AHI. Something is amiss, for sure, and you won't know until they can read the data for you.

How long have you had this machine? What is the pressure set to? What was your titrated pressure? If, as BlackSpinner suggests, it is mouth breathing, a different mask may be needed or try taping. So a search for 'taping' and you will finds tons of information about that.

[downsize]

You are probably mouth breathing. Try a full face mask or taping your mouth to eliminate that possibility.
Then try upping your pressure some more.

Or maybe you could rent an APAP from your DME for a week?

No mouth breathing going on ... I am taping.

[downsize]

Your machine is data capable, however, it needs a special card reader in order to import the data into the software you install on your computer. The card readers are very hard to come by since your machine is an old model. That said, your DME should be able to read the card for you and give you a report. Do you use a local DME that can do that for you? If so, call and ask if you can bring in your machine for a reading and tell them about your very high AHI. Something is amiss, for sure, and you won't know until they can read the data for you.

How long have you had this machine? What is the pressure set to? What was your titrated pressure? If, as BlackSpinner suggests, it is mouth breathing, a different mask may be needed or try taping. So a search for 'taping' and you will finds tons of information about that.

Huh ? My machine is only one year old. As far as a card reader .. or a computer being involved ... I am LOST. I am simply reading the "results" from the Clinical Menu that my machine shows every morning. I am taping, so no mouth breating is happening.

[Emilia]

Huh ? My machine is only one year old. As far as a card reader .. or a computer being involved ... I am LOST. I am simply reading the "results" from the Clinical Menu that my machine shows every morning. I am taping, so no mouth breating is happening.

You may have owed it only a year, and it is still available to purchase, but it is an old model. ResMed updated the series to the S9 over a year ago. They updated the algorithm, the software, moved to a standard SD card, and made the machine nicer to look at. The card in that particular model is proprietary and requires a special card reader which is now very hard to find to purchase.

You should have a card in the slot on your machine. If you are being monitored for compliance for insurance purposes, someone checks your card/machine to be sure you are using it for at least 4 hours a night. If you are not being monitored for compliance, and there is a card in your machine, you can have the card 'read' by your local DME to get a report on the efficacy of your therapy.

I take it you aren't tech savvy and don't wish to monitor your own therapy? If not, the only way you'll know what is happening minute by minute, hour by hour overnight, is to have the data read. The LCD screen you are reading only gives you averages and not detailed info so you can pinpoint the problems.

[avi123]

I
I do not have access to a sleep study at this time ... What are the things that could be causing these high AHI numbers ? Thanks

Underlying medical conditions could cause the AHI to be hi.

[downsize]

No ... I am not very Tech savvy, and I do not have a lot of knowledge about apnea details past the fact I have to sleep with a machine that worked PERFECTLY for me for 10 years. I only know I am having some issues now, and do not have the luxury of a sleep study at this time. But I can now see I will have to eventually find a way to see a professional. Thanks

[Emilia]

Well, I am sorry you are going through this period of bad therapy. For 10 YEARS you didn't learn how to monitor your efficacy..... pretty amazing. How do you even know if it is giving you proper care? Have you ever had a doctor or DME view your data and check to be sure you are getting the proper pressure or care? Going it alone is fine if one has the ability to monitor the data and tweak things as needed. Those who don't know how to do that or don't feel they can handle it, need to have someone who can read the data and help them tweak things.

I am sure you are quite sleep deprived at present with those AHI results. I understand the brain fog that comes along with that. Please try to get a handle on this or have a spouse/partner/good friend who has a clear brain help you navigate through this.


Suggestion: you could contact a local DME to see if they can read the card in your machine and give you a copy of the report.

Suggestion: you could see if you can rent an Auto cpap with full data capability so you can do a home titration to determine a better pressure for yourself

Suggestion: you could see if a local DME can do a bench check of your Elite II to be sure nothing has gone haywire since you say it has worked 'perfectly' until recently. This will help you determine if it is you or the machine that is having issues.

EDIT: It occurred to me that you should also check your hose for any minor tears or leaks. It might be as simple as that...lost therapy via a hose leak. Just a thought.

[LinkC]

At this point, your best move would be to see your sleep doctor. Something is obviously wrong. If not mouth-breathing, you need to investigate.

[Pugsy]

I am with LinkC on this one. Something is wrong.

Would it be possible to get your hands on a S9 Autoset? Trial or rent for a week or so. Then you could easily use the software and get a better idea exactly what that AHI is composed of. More specific details are available on the latest model than you could see if you did have that card reader needed for S8 machines.

There may be a reason why that AHI does not seem to respond to the increase in pressure. If they are possibly central in origin it might be one explanation.

Any way that you could also have an overnight pulse oximetery done to see if that AHI is also associated with low oxygen levels?

[rested gal]

downsize, you actually can get quite a bit of useful information from the numbers you are able to look at on your machine -- without software.

Your ResMed S8 Elite can show overnight results -- the "daily" efficacy results...more useful than the "weekly/monthly" averages. You've apparently already been checking that -- the "daily" results figures.

You can also see the daily AHI broken down into the Apnea index and the Hypopnea Index. Here's where it gets interesting. If the Apnea index is very low, and if it's a high Hypopnea Index that is creating the high AHI you've been seeing, this is something to consider: ResMed's S8 machines have generally produced a rather high "HI" (Hypopnea Index) compared to other brands of CPAPs for same user, same settings. For years, I've suggested that anyone using an S8 machine mentally cut the Hypopnea Index in half and then add it to the Apnea Index, coming up with a new (lower) overall AHI number...if they want to get a more realistic (for want of a better word) comparison their ResMed (S8) "AHI" with the kind of AHI users of other brands get.

It was all about the definition of "Hypopnea" that each brand's designers chose to use. Each brand had it's own line drawn in the sand for when a flow limitation becomes "bad enough" to be called a Hypopnea instead of still just a "flow limitation." What was still considered still just a "flow limitation" to Respironics, for example, was a "Hypopnea" to ResMed. That doesn't mean that one brand or the other treated a person better. Nor did it mean that one brand let things slip by that the other caught, or that one brand was better at identifying events than the other. It was (still is) purely a matter of where each brand's designers choose to draw an arbitrary line. On this side of the line it's still a flow limitation. On that side of the line, it's a hypopnea.

When ResMed designed the newer S9 model, they changed the way they defined when a flow limitation gets labeled "Hypopnea." And just like magic, people who had been using S8's and seeing a Hypopnea Index of, say 6.0, were now seeing HI's of just 1.0 or 2.0 with their new S9 machines. With an S9 machine it's no longer necessary to "mentally cut the Hypopnea Index in half" in order to get a reasonable comparison of a ResMed AHI with the AHI of other brands.

So, if I were you, I'd start jotting down the breakdown of the AHI from your S8 machine each morning. Keep a record of the AI (apnea index) and the HI (Hypopnea Index.) If the AI is very low (1.0 or lower) and it's the HI that is adding so much to your AHI, it's not as worrisome as if you were having a great many apneas contributing to your high AHI.

All that said, a "treated" AHI of 28 is wayyyyyy too high -- any way you cut it. Even if your AI was only 0.0, the sheer number of hypopneas it would take to create a HI that would (if "halved" and then added to the AI) create an AHI of 14 (half of 28)....that would be too many hypopneas. I went into all that "definition of hypopnea" in the S8 vs other brands as well as the newer S9 simply to get to this:

Your AHI is bad. But perhaps not as bad as it looks. Start cutting the Hypopnea Index in half and recalculate your AHI when looking at daily results with an S8. That's not going to solve the problem, but it would probably give a more realistic view of the extent of the problem.

[downsize]

Lots of REALLY great information here ! I sure appreciate everyone.

But the news is about to get worse .... Last night I tried an experiment and turned my machine back down to the 11 it used to be set at. Here are the numbers :

Leak ....0.00
AHI ...... 51.2
AI ....... 23.1
HI ........ 28.1

The only good news I can see from this, is it DOES appear to be a pressure thing. The question is : Do I keep going up very slowly in pressure every night until the AI drops down below 5 ?
Looks like either way I am heading for HIGH pressure

[nanwilson]

You should not change your pressures willy-nilly. Meaning....make a change of .5 or 1, then try it for a week, if that doesn't help, do it again, but you need to stay at one setting for 5 to 7 days to see any differences. Case in point,my machine is set from 10 to 13 my ahi is usually 0.0, but Monday night it was 0.8, and my flow was way off and hitting 13 all night. I paniced immediately and thought I had better raise my max to 15 tonite. But I chewed on it all day, by bedtime I thought hmmmm could have been just me....I know better than to panic after one night of different numbers. I just got up and read my results for last night ahhhh I'm back to 0.0, so it was just a freak of a night. What I'm trying to say is stick to a setting for a few nights, then if its still not working, raise it again until you get to where you need it. You can't see if a change works or not in just one nights data. My biggest advice would be to see a doctor...its definitely time to do that you may have an underlying health problem.
Good luck and cheers
Nan