Extreme fatigue despite "low" (<5) AHI

[Uphold9887]

Making a new treatment thread as my others have gone dead it seems.  May be helpful to start fresh.

35y male here.  Not overweight.  Have been using CPAP for a little over 2 years.  It was beneficial at first, but lately I'm struggling to see major benefits, and it seems like my symptoms are getting worse over time (extreme fatigue, brain fog, mild headaches).  I am waking up a lot in the mornings, usually multiple times and rolling back over to sleep.  I usually get about 4-5h straight before the repeated awakenings seem to start happening.

Currently using a nasal mask (AirTouch N20), 10-15 pressure on APAP mode.  Using mouth tape and a chin strap as I'm a mouth breather at night.  Sometimes i wake up and feel like i'm trying to breathe through the tape rather than my nose.

Lately nights are generally between 2-4 AHI, and most nights my O2 sensor (Lookee brand) reports O2 drops into the high 80's (usually 88%).  Sometimes the number of drops is quite high.  Rarely do i get a night that keeps me in the 90's the whole night. Importing the data into OSCAR shows a ton of Pulse Change (PC) and SpO2 drop events throughout the night.

I have experimented with higher pressures and CPAP mode, however I notice a trend that higher pressures are actually causing more events, and I think i am waking up more often.  My current settings are the "best" I've had for a couple months, but I seem to be plateauing in getting AHI's down.

Any ideas?  I've been reading a lot about UARS, soft pallet collapse, other types of issues and I wonder if maybe I'm experiencing something like this.  My current sleep doctor doesn't think another sleep study will be helpful (the only in lab study I had was the one that diagnosed me initially without the machine).  I'm in the process of waiting for another referral to a new sleep doctor (I'm in Canada so that appointment isnt due until September).

I also have no idea if it would make sense to try to get a VAuto machine (not sure what that means) or an ASV machine, although they seem quite expensive.

           

[Uphold9887]

Here is a closeup of some of my OA and CA events from that same night:

   

Here is a summary from the O2 ring:

   

[Uphold9887]

*crickets*

Bump? Any input from the experts?

[fishfinderG]

Not one of the experts but I have learned some things over the years...  Can you zoom in on some of the OAs you have and show around a 5 minute window as well as another screenshot of a one minute window with the OAs 30 seconds in?  I want to see what your breathing looks like before the OAs and at those two zoom levels so that we can better understand what might be happening.  Your flow limits are low so it doesn't seem like a different machine would benefit you, but maybe someone else will have a different take on that.

[Sleeprider]

Your therapy is generally good except for the cluster of OA at 04:00, 05:50 and 08:40 which is most likely positional https://www.apneaboard.com/wiki/index.ph...onal_Apnea In other words, all of your apnea is explained by chin-tucking or similar positional obstruction to your airway from bending the airway in the neck area. If you resolve the positional issues it may be possible to reduce your pressure to increase comfort, and even try fixed pressure to minimize potential for sleep disruption. The EPR 3 setting you are using is effective at controlling flow limitations, and whatever pressure range or setting you choose, you should continue to use EPR. The only remarkable feature in your respiratory data is an inverted inspiration/expiration time. We look for expiration to be equal or up to 2-3 times longer than inspiration. This inverted I:E timing can be caused by flow limitation or even an error by the CPAP machine in properly detecting I:E flow transitions. A more zoomed view of the respiratory flow rate where the wave-form is clearly visible might reveal the issue. 2-3 minute zooms are best for this purpose.

[DaveL]

Sleeprider thank you for your explanation and the links you provided. They are very helpful.

@Uphold3887 thanks for asking the question. It helps me a lot. I'm from Mississauga.

I use the same mask. I have the same machine.

I'm very interested in seeing how you resolve this issue.

Thank you
DaveL

[Uphold9887]

Thank you for the detailed responses.  Here is last nights overview:

   

Looks like there are more CA events than the previous snapshot.

Here is a 5 minute window of some OA events:

   

Here is a 1 minute window:

   

[Uphold9887]

Here's a 3minute window over a CA event

   

I have purchased a 3.5" soft cervical collar which I'm going to test out tonight.  I'm certain its going to give me some difficulty trying to fall asleep, but hopefully I will adjust to it and breathe better!

Let me know if you need to see any further graphs.

[AshSF]

I used to be in a similar position. For me, the reason was that APAP with its pressure changes would kick me out of deep sleep states to shallower ones. And though my AHI was less than 1 every night, I had brain fog and fatigue every day.

After doing some research in Apnea journals, I found a study which estimated that 17% of APAP users can't handle pressure changes. 

So, I moved from a 6-12 APAP range to a fixed 8. And the difference was amazing. I have never had to do any other tweaks and I sleep well and stay energetic thru out the day since then (that was 8+ years ago).

In your case, you can try setting your machine to a fixed pressure of 11cm H2o for a week and then evaluate.

[Uphold9887]

I used to be in a similar position. For me, the reason was that APAP with its pressure changes would kick me out of deep sleep states to shallower ones. And though my AHI was less than 1 every night, I had brain fog and fatigue every day.

After doing some research in Apnea journals, I found a study which estimated that 17% of APAP users can't handle pressure changes. 

So, I moved from a 6-12 APAP range to a fixed 8. And the difference was amazing. I have never had to do any other tweaks and I sleep well and stay energetic thru out the day since then (that was 8+ years ago).

In your case, you can try setting your machine to a fixed pressure of 11cm H2o for a week and then evaluate.

Thanks for your input.  A little over a week ago I just switched back fromexperimenting with a fixed pressure of 13cm to APAP again at 10-15.... switching to APAP gave me a few days' worth of noticeable improvements, but the last few days it seems like I'm more or less back to square one with my fatigue.  Really hard to tell if CPAP vs APAP is any better or worse, honestly.

@sleeprider: I tried the cervical collar last night and it looks as if it has helped reduce events

   

However, I woke up after about ~5h of sleep, started tossing and turning and could not fall back asleep once again.  This seems to be a very common theme the last few weeks, waking up after about 4-5h of solid sleep only to toss and turn (sometimes i sleep in between waking, sometimes it just doesn't happen).  I dont know if i qualify as having insomnia, but, it sure feels like it sometimes.  I'm sure this is probably half the battle with my significant fatigue, and I'm not sure what, if anything, can be done to help with this...

As always, I'm happy to hear any input and suggestions from the wise folks here.  Thanks very much for your time!