Elevated head of bed increases CA and AHI

[silverdr]

I 've been using airsense 11 for 5 months with great results but had to elevate the head of my bed (sleep number bed) because of a recent attack of vertigo. This goes away with slight elevation into what is called snore position. The vertigo is actually gone but I kept the head slightly elevated.
I go to sleep early (8pm) and usually awaken at 4 AM , get up go to the toilet and then return to bed . Between 8 and 4 my Ahi score is less than 2 but after 4 ahi will then be high enough to make my Ahi for the night is over 5.
This is the time when most of my CA's occur and since elevating the head the CA's have gone from 20's to 50.

Im gonna lower the head tonight to see if this improves but has anyone seen similar reactions with elevating the head. Remember the OA's are not increasing.

[Jay51]

I sleep on a 45 degree angle wedge (entire upper body) pillow.  My SPO2 improved significantly when I did this.  I have an S9 asv that I have taken naps with in a recliner (about a 45 degree angle).  On my back, my AHI was bad.  Much better though at the 45 degree angle.  I think sleeping with the upper body elevated decreased the effects of gravity on the my tongue tissue, etc.  In other words, it decreased obstructive apneas (OA's).  

Here is how I think it relates to CA's - you are ventilating better now at the higher angle and exhaling more CO2.  CO2 building up is the main driver to breathe.  

A lot of people experience something similar this when they start cpap - they have some treatment emergent CA's because they are simply breathing better (ventilatiing better).   Increased CA's can simply be a by product of breathing better.  Most people adapt to it though in time (the CA's decrease).

Just my thoughts and observations.