Snore index relative to AHI

MeChuck · Post by **MeChuck** » Sun Nov 19, 2006 6:01 pm

I was just wondering if someone can explain this to me a little better. I have read a lot of postings trying to find the answer, but don't understand why at 9 cm H2O my Snore index is way up and AHI is the lowest?????
Hope the pictures work..

[img][img=http://img297.imageshack.us/img297/5158/sisbs5.jpg][/img]
[img][img=http://img141.imageshack.us/img141/3462/ahisyt6.jpg][/img]

MeChuck · Post by **MeChuck** » Sun Nov 19, 2006 6:10 pm

Images didn't work... maybe a direct url??

http://img297.imageshack.us/img297/5158/sisbs5.jpg
http://img141.imageshack.us/img141/3462/ahisyt6.jpg

Snoredog · Post by **Snoredog** » Sun Nov 19, 2006 7:13 pm

AHI is the one that is important. Looks like about 9.3 is your ideal pressure. you have to go beyond 10 before your snores start to drop but then it looks like your AHI is on the upward swing from there.

I wouldn't worry about the snores unless you feel better at the higher pressure.

Wulfman · Post by **Wulfman** » Sun Nov 19, 2006 7:21 pm

A Snore Index of "6" is NOTHING.
I had the same AHI / SI relationship. Give it some time. I agree with Snoredog.....concentrate on your AHI.

Best wishes,

Den

rested gal · Post by **rested gal** » Sun Nov 19, 2006 7:41 pm

Chuck, as an experiment some time ago, I used two different brands of autopap on alternate nights with same setup exactly -- same mask, same separate humidifier, same pressure range, same taped mouth. The REMstar Auto (with C-Flex turned off, to keep it as similar as possible) marked up a LOT of snores for me, while the PB 420E auto noted none or almost none.

I was a BIG time snorer before cpap, btw. To give you an idea, there was a night when I set the 420E auto to minimum pressure of 4, max of 4...using it like a straight cpap as low as it could be set just to see what the data would show. In a 6 hour night, the 420E counted almost 2,000 snores. So, the 420E will note them if they're there!

Anyway, back to the regular pressure range... I kept switching machines back and forth for a week or so. I felt equally good using either machine. I finally decided the REMstar was tallying up something other than "real" snores from me -- perhaps an inaudible flutter so soft that it really didn't matter. Bed partner heard no snores.

I had both machines set for 9 - 16. They rarely touched 14 for brief periods on some nights. The pressures actually used during the nights by both machines were essentially the same. Whatever the REMstar was counting as snores wasn't driving the pressure up or anything. I finally stopped even bothering to look at the snore Index on the REMstar. Maybe the newer ones are not as ticklish about it.

I'd just ignore the snore index entirely and go by the AHI and how you feel, as Snoredog and Den said.

bairdbeth · Post by **bairdbeth** » Sun Nov 19, 2006 9:31 pm

Rested Gal, I think you are right and that Respironics machines register any noise as a snore. I have the M series Pro and have had snore index as high as 159. My AHI that night was 0.2. Another night it was 120 with AHI of 0.0. My Si has ranged from 56 to 159 with AHI's from 0.0 to 0.8. Most events in 1 night was 6 in a 11 hr period ( Saturdays I still sleep in) My daughter says she doen't hear me snoring in the mornings when she is up before me, but my machine says I am. I think the pressure moving my soft palate and stuffy nasal passages are putting my SI so high. I feel better, so I am not going to worry about it. I will mention it when I go to my first visit to the CPAP clinic in 2 weeks.

JohnD · Post by **JohnD** » Sun Nov 19, 2006 9:48 pm

I have the M Series Cflex and I am getting the same thing, a high SI, but low AHI. I think the M Series is indeed measuring something other than a full blown snore.

linda b · Post by **linda b** » Sun Nov 19, 2006 11:07 pm

One thing I know for sure is that the Respironics Remstar Auto is very sensitive to hose noise - be it caused my a lot of hose movement or excess water in the hose. The only time my snore index (or vibratory sounds as they call it on Encore Pro 1.6.22) has been high were nights when I know there was quite a bit of hose movement (at my daughter's and was not using my hose hanger contraption) and another night when we were camping and it was very humid and I had a humidifier attached causing a considerable amount of rainout.

MeChuck · Post by **MeChuck** » Mon Nov 20, 2006 7:38 am

Thanks to all for the fine information, puts my mind at ease now anyway. I was turning the pressure up to get the snores down, then turning it down. Didn't really know which way to go. I have a better idea now. When I stop to think about it now,,,, When my snore index was high, I always asked my wife if I snored a lot, she always said no I didn't but as usual, didn't listen to it, so it didn't compute. (Story of my life). I will concentrate on my AHI now and Ignore the SI. Thank you all so much for the 4.0 info as usual........ Chuck

Snore index relative to AHI

Snore index relative to AHI

M series ...same high SI