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AHI question - GrammaBear - 04-14-2014

I recently saw my ENT (ear, nose & throat) doctor for a seasonal allergy problem. She recommended one of the 'over-the-counter' brand of antihistamine - not a decongestant, just the antihistamine. I've noticed since I've been using it that my AHI is lower now than it was. It is my understanding that it should be under 5. Mine are now anywhere between 0.5 and 2.8.

I've also noticed that under the AHI number which might be 0.8 that there is also a 'central' number which today was 0.2. My sleep doctor never explained what the central number meant and I am curious. Is it something I need to be concerned about?

I use the S9 Autoset with the AirFit P10 mask.


RE: AHI question - mjbearit - 04-14-2014

I assume you never had CAs until recently? How long ago did you start taking the Antihistamine? It could be that your body is getting so much oxygen compared to what it was that it just forgets to breathe sometimes. .2 is not really what I personally consider significant. "Central" is Central Apnea or CA. This is not an obstruction to being able to breathe just simply NOT breathing. Basically your brain "forgets" to send the signal to the rest of the body to take a breath. It can be serious if you have a bunch of them, but it sounds like you do not. It could be that these will disappear completely once your body gets used to the new drug. It might be wise to keep an eye on those and say something to your sleep doc if you start having a bunch of them though!


RE: AHI question - PaulaO2 - 04-14-2014

short answer: Central apneas are included in the AHI so as long as the AHI remains below 5, all is good.

Long answer: Central Apnea (CA) is where the airway is open but the brain, for various reasons, doesn't think you need to breathe. There's no snoring, no struggle, no nothing. Eventually, the brain gets better messages and you start to breathe again. Sometimes it is due to the blood chemistry being a little off or the brain thinking it is off. It sounds extremely frightening BUT as long as those numbers stay below 5, all is well.

I typically have central events each night, sometimes I have more of them than I do obstructive events. Their number stays low and my overall AHI rarely goes over 3.5 so I'm not concerned at all.


RE: AHI question - GrammaBear - 04-15-2014

I am going to try and find the original 'sleep study' I had and see if CA events were mentioned in that print out. The sleep doctor I had then didn't explain one durn thing except that I had sleep apnea - and someone would deliver a cpap machine in two weeks. That was my introduction to sleep apnea. Thank you for your explanation of CA.


RE: AHI question - PaulaO2 - 04-15-2014

Really, it's nothing to be concerned about.




RE: AHI question - GrammaBear - 04-15-2014

(04-15-2014, 02:02 PM)PaulaO2 Wrote: Really, it's nothing to be concerned about.


Thanks for your reassurance Paula. I don't know as I'm concerned so much as maybe curious. I found the AHI information by accident on my machine and to be very honest I still don't know how I 'found' it. Anything I've learned about sleep apnea has come from the kindness of this forum - for which I am very grateful.

I do take a very small dose (0.5 mg) of Xanax at bedtime and I would like to break my dependency on that medicine as a sleep aid. However I'm trying to break my caffeine habit first and one thing at a time.




RE: AHI question - PaulaO2 - 04-15-2014

If you look on your machine, I think it is included in the AI total. I can't remember if it is broken down into it's bits.

In the software, it is referred to as "clear airway" events since that's what it is.

If you see just the letters:
AI - Apnea Index (could include both obstructive and central)
HI - Hypopnea Index (or Hawaii or your machine could just be greeting you, ya never know)
CI - Central Index
AHI - all three combined

The "index" is determined by the number of events divided by the time slept.


RE: AHI question - trish6hundred - 04-15-2014

Hi GrammaBear,
Sounds like your CPAP therapy is going really well, keep up the good work. Good luck on trying to gett off the caffeine, as you said, "one thing at a time."