CPAP for months with no problems but feeling terrible

I started using my CPAP machine about 4 months ago, but from the numerous times I've read this board I realize that the time doesn't really matter.

To make a long story short(ish), I've fixed everything that ever bothered me about using CPAP including:
-Mouth Leak: Taped my mouth while sleeping
-Breathing in Water: Changed humidity setting to 2
-Getting tangled in hose: Rigged a hose bungee (similar to a mouse bungee) to hold tubing and still let me move
-Mask Comfort: Changed to a nasal pillow
-Pressure Settings: Found the lowest pressure that I could use to keep AHI under 1.0 (5.8cmH20)
-EPR: Lowered until I no longer had CAs (1) (I know it supposedly isn't supposed to cause these but it does for me)
-Turned off ramp: Resulted in less awakenings at night
-Air Temperature: (CPAP Machine has heated tubing) I use 76 degrees Fahrenheit which I find is most comfortable

In addition to doing those things to make CPAP more tolerable I also changed other things so I could keep the pressure on a lower settings for more comfort
-Learned to sleep on my side
-Bought a Mandibular Advancement Device and adjusted to using it (SnoreRX)
-I'm already in good shape, I can run a 5k in 20 minutes and a half marathon in 1:50.
-I don't smoke or drink, I have a healthy diet with low amounts of meat, high vegetables, no sugar or other simple carbs, and lots of water.
-Vit B/D/Iron levels are all fine, same with thyroid and test

I regularly sleep through the night with CPAP (or at least I don't remember waking up more than 1 or 2 times) and my AHI is under 1, but I still feel really tired. I've also added user flags to SleepyHead to track 20% and 50% reductions in flow that only occur for 8 seconds or longer figuring that maybe my AHI is low but I'm still having lots of events that are not being registered. These are not occurring either.

Lately, I've tried sleeping without the CPAP (with MAD and on my side). The thing is, I feel considerably better when I sleep without it. However, I know that my AHI must be higher without it because when I lower my settings on the CPAP to 4cmH20 I start seeing AHI of ~5 (meaning the side sleeping and MAD aren't totally treating me).

I have a Fitbit Charge 2 which is actually remarkably good at tracking sleep stages (it actually shows awakenings at the exact same times SleepyHead shows apneas/hypopneas). Additionally, periods which it logs as REM sleep show higher breath rate variability in sleepyhead which is a good indication of REM.

I've noticed that when I sleep with the CPAP machine I go into rem sleep for about 10-15 minutes and then have about 20 minutes of restlessness and then back to light sleep (no events). It's as though I get through 10 minutes of REM sleep, and then wake up completely.
When I sleep without the CPAP (but with the MAD and on my side) I stay in REM sleep but have many 'restless' moments (30seconds to a minute) which I've realized match up with hypopneas from SleepyHead. However, even with the restless moments I stay in REM sleep for about 40 minutes (depending on how early in the night it is).
The end result is that with CPAP I typically hit about 8% REM sleep by time and without it I hit about 22% REM sleep by time.

Anyway, I've scoured the internet and can't find anything else to help so I'm not super hopeful. But if anyone has had a similar experience I would love to hear about it.

My setting pressures are:
IPAP: 5.8cmH20
EPAP: 4.8cmH20
(CPAP: 5.8cmH20 with EPR at 1)

I believe you may have outsmarted yourself being so careful, and lowered the pressure too far. It's one thing to avoid aerophagia, but another to make treatment ineffective, and the 'centrals' you might have experienced were as likely the few many have when drifting off and just before awakening, not true centrals but 'sleep-wake junk', not problematic at all. Do you think you might try raising your pressure again to a slightly more useful level and see what happens - it does seem quite low now.

Have you downloaded Sleepyhead software (free) to actually look at what happens overnight to get a better idea of where problems could be and possibly tweak things to fix them?

I don't believe heart rate variability gives as accurate indications of sleep stages as EEG monitoring does. This means that until you correlate your fitbit information with the EEG data from a sleep study you are just guessing.

The question remains why do you feel better without the xPAP machine...?

One possibility is that you have a sleep debt. When using the xPAP machine you are achieving deeper levels of restorative sleep and this results in repairing your body. While you are being rested the overall results can be exhaustive.

This article seems informative...

http://www.nature.com/npp/journal/v28/n ... lback=true

Julie wrote:I believe you may have outsmarted yourself being so careful, and lowered the pressure too far. It's one thing to avoid aerophagia, but another to make treatment ineffective, and the 'centrals' you might have experienced were as likely the few many have when drifting off and just before awakening, not true centrals but 'sleep-wake junk', not problematic at all. Do you think you might try raising your pressure again to a slightly more useful level and see what happens - it does seem quite low now.

Have you downloaded Sleepyhead software (free) to actually look at what happens overnight to get a better idea of where problems could be and possibly tweak things to fix them?

I use Sleepyhead every day.
With the CAs, they disappear when I turn the EPR off. They appear when I have it on. If they were just the normal CAs that you see in everyday sleep you'd think I'd see them in both cases.

Originally, before I started sleeping on my side and using my oral appliance, I had to use a higher pressure. Both of those have contributed to me being able to lower my pressure.
Also, if I have an AHI under 1, is there any reason to raise the pressure?

HoseCrusher wrote:I don't believe heart rate variability gives as accurate indications of sleep stages as EEG monitoring does. This means that until you correlate your fitbit information with the EEG data from a sleep study you are just guessing.

The question remains why do you feel better without the xPAP machine...?

One possibility is that you have a sleep debt. When using the xPAP machine you are achieving deeper levels of restorative sleep and this results in repairing your body. While you are being rested the overall results can be exhaustive.

This article seems informative...

nature (dot) com/npp/journal/v28/n1s/full/1300146a (dot) html?foxtrotcallback=true

Breath variability
Respiratory rate variability in sleeping adults without obstructive sleep apnea
From page 4: ". Initially, the spectra display a regular
peak pattern typical of steady breathing with the subject
in stage N2. As the subject enters REM, there is a
significant increase in amplitude, reflecting greater nasal
airflow, with noticeable spectral disorganization. The
spectra revert to their initial pattern with return to N2."

Also see sporttechie (dot) com/fitbit-study-fitness-devices-accurately-track-sleep-stages-unlike-calories/ on the accuracy of the fitbit sleep stage tracking

The times of events on the fitbit summary match exactly with the timing of the SleepyHead data I view. I'm reasonably convinced.

Thanks, for the article. The

Can't edit my previous post but the sleep debt idea is interesting. I had read about it before but figured I wouldn't feel worse while paying it back. That was kind of an assumption without any basis. Thank you for the idea.
It doesn't really explain why I get so much less REM sleep using CPAP though.

Discouraged wrote:Can't edit my previous post but the sleep debt idea is interesting. I had read about it before but figured I wouldn't feel worse while paying it back. That was kind of an assumption without any basis. Thank you for the idea.
It doesn't really explain why I get so much less REM sleep using CPAP though.

Any indications of RLS or periodic limb movement issues? Just asking because its presence could fit the pattern of less REM on CPAP. Long explanation but I'll spare you that if it's clearly not relative.

Well, AHI isn't everything of course, but a point. Can you post a few SH graphs to Imgur.com and leave a link here so others more knowledgable about your set up can comment?

kteague wrote:

Discouraged wrote:Can't edit my previous post but the sleep debt idea is interesting. I had read about it before but figured I wouldn't feel worse while paying it back. That was kind of an assumption without any basis. Thank you for the idea.
It doesn't really explain why I get so much less REM sleep using CPAP though.

Any indications of RLS or periodic limb movement issues? Just asking because its presence could fit the pattern of less REM on CPAP. Long explanation but I'll spare you that if it's clearly not relative.

No, no indications. I have a good friend with RLS and I don't have any of the symptoms that they do.
Thanks for the idea though

Julie wrote:Well, AHI isn't everything of course, but a point. Can you post a few SH graphs to Imgur and leave a link here so others more knowledgable about your set up can comment?

Yeah, I'll post back tomorrow with graphs.

rls and plmd are different. plmd only happens when you are asleep, but would have been picked up in a lab sleep test or a good home sleep test with movement sensors on your ankles.