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I wonder what definition is used when the magic number of AHI=5 appears. That's suposedly the "normal" bopundary.

Anyone know?

Thanks

builta wrote:Hi,

Actually you need to have a two dimensional array. One for the manufacturer of the blower and the other for the AHI. Without that I don't think that the data will separate into a clear pattern. It is even possible that you would need to have a third dimension of mask type.

Hi All

I wonder how significant the difference in results would for the same machine, and a variety of different masks, possibly all with different leak rates.

My average AHi over the last 57 days has been 1.8, but has varied from less than 1.0 to less than 4.0, depending on the length of my beard, strap cushioning used, and many other health factors.

It is an interesting poll, and just leaves me wanting more.

All the above goes to indicate that we need a better format for polls, such as being able to tell how many members participated, even with multiple choices, and can at least get an accurate result for the sample of Forum members who participate.

I am looking into how we might be able to achieve this, and hope to post about this soon.

Fun polls will always be with us, but I think that more serious polls are now gaining popularity, but are severely restricted in what they can deliver because of the very basic format they are confined to.

cheers

Mars

rested gal wrote:

Jason S. wrote:My impression was that most ResMed users still had AI that were significantly higher than their HI.

That wouldn't be my impression. I'd think it would probably be the other way around for most ResMed users -- an HI (hypopnea index) significantly higher than their AI (apnea index.)

Velbor wrote: Such adjustments (as Rested Gal rightly, carefully and continually emphasizes) are adjustments in our THINKING, not adjustments of data.

Thanks, Velbor. What a good way to put it -- "adjustments in our THINKING, not adjustments of data." I like that!

I'm one of Jason S.'s statistics: I'm a Resmed user, but have very few hypopneas (0 to .7 most nights), so my Centrals and Obstructives are always my concern, so I guess my vote was more "apples to apples" -- usually in the 3 range (doc doesn't want me to up my pressure and he has my EPR higher due to aerophagia issues...it's always something...)

When on my Resmed S8 Autoset II, my ahi's averaged between 10 and 20 consistantly, mainly hi's. My ahi's on my S9 Autoset have averaged between 1 and 3, hi's have been almost eliminated.

My average AHI after 10.5 weeks is 2.4, and dropping. In the last 7 days the highest has been 1.7. Last nite was 1.0. I have made no pressure adjustments. Still running on APAP , range of 4-20.

My DME is of the opinion that the AHI will drop, as time goes on. The day I started therapy, she showed me the results of a 5 year CPAP user, aged 65, who had a starting AHI similar to mine. Her long-term average is running at 0.1. This is what I am aspiring to.

To be honest, I just plain don't pay a lot of attention to my AHI at all in any event. I am more interested in the number and length of apnea events and hypopnea events along with SaO2 desaturations and if I could do so without waking myself up every time.... associating these with my blood pressure (I have actually gone out and bought an Accutor automatic recordning blood pressure machine but having the cuff inflate every five minutes or whatever is sure to wake me up). I would also like to relate ALL of this to an EEG on a regular basis to compare to REM sleep and awakenings, but this too would be impractical. So I content myself with watching apnea and hypopnea events along with desats and all of the other usual numbers that have an effect on same (leakage etc.)

To me, AHI is an arbitrary number that will vary from manufacturer/model to manufacturer/model at best. To wit, changing from the S8 series to the S9 series got me all excited that I had bought a great machine based on numbers being returned.... but it appears that it was only a change in ResMeds algoriths.

Past six months my AI is typically .1 and HI is 2.3 on a Resmed S8 for a reported AHI of 2.4 with a leak rate of .02 and average pressure of 18.4.

This further supports the argument that Resmed's earlier machines were aggressively reporting hypopneas relative to their competitors.

AHI is 2 or less, with OA being .07 or less. don't concern myself w/ H's . duration of A's avg. is around 12 sec......did have one a while back lasting 30 sec. that one got my attention.....must have been dreaming of Alice & the White Rabbit

I reported my number from my tiration. AHI = 0.3. All H, no A.

I find it odd that so much emphasis is put on the AHI, and it doesn't include an average or total duration of apneas.
The duration bothers me more than the number, especially since mine tend to cluster in the later part of my sleep.

deerslayer wrote:AHI is 2 or less, with OA being .07 or less. don't concern myself w/ H's . duration of A's avg. is around 12 sec......did have one a while back lasting 30 sec. that one got my attention.....must have been dreaming of Alice & the White Rabbit

Deerslayer, where do you see the duration of apneas on the data? I'd love to know that.

If he's using the Encore Pro software he could be getting it from there. I know that the graphs have I belive (5) 1 minute groups per strip. I can't remember off hand if there are tic marks at the bottom. I like to check it out too to see how long mine are but haven't paid much attention lately as I have been transitioning to a new mask.....which has gotten me my lowest ahi yet of 3.8.

Jason S. wrote:

jnk wrote: The point, Jason, is that statistically speaking, because of the way ResMed counts HI, most ResMed users have high HI indexes relative to their AI indexes.

So you're saying that most ResMed users have an absolute HI that is higher than their absolute AI? If that is true, then I agree with you. But if you are saying that ResMed users have a higher HI/AI ratio then non ResMed users, but still for most ResMed users the HI is significantly lower than their AI, then you are wrong. My impression was that most ResMed users still had AI that were significantly higher than their HI. And in the rarer case like yourself, you have an HI that is higher than your AI. But that is not the norm for ResMed (or non ResMed users).

I just have to say that I have a Resmed 8 and a Resmed 9( which my husband uses) and both machines always read a high HI but the AI is always low.
Thanks!

Congrats getting it within that range Jason! Especially on a FFM. I average between 2 - 3. You can see the equipment i use.

Starlette