Understanding my long-running issues with CPAP and BiPAP

[Pugsy]

what causes post-arousal centrals? I would have expected that I would be breathing normally post-arousal?

Actually our awake breathing is very irregular when compared to asleep breathing and a post arousal central is nothing more than a little pause in our own breathing and the machine flags it as a central.

Did you know that when we turn over in bed we often hold our breath? That would be considered a post arousal central apnea per the machine because the machine can only record air flow....it has no way to know if we are asleep or awake.

Here's an example I like to use even though it doesn't really have centrals flagged...it has other stuff flagged though and I wasn't asleep when they got flagged. The machine isn't terribly accurate when it comes to awake breathing irregularities.
I circled the asleep breathing in red. Note how rhythmic the breathing is and how irregular it is after the red circle ends.



And here is the same time frame zoomed out further so you can get a bigger picture. I have more arousal/awake breathing than I do asleep breathing



Let me go take a stroll through your SleepHQ report. Give me a few minutes.

In the meantime take a look here....I have some good examples of false positives here.
It make take you to the bottom of the page...scroll up to the top.
viewtopic.php?f=1&t=187556&p=1449368&hi ... e#p1449368

[Pugsy]

Okay...
The bulk of your central flagging is definitely post arousal...I counted maybe 15 of those.
1 or 2 asleep centrals...perhaps a sleep onset central which is normal and no big deal.
And 1 asleep central that I don't think is sleep onset.

Your flow rate is loaded with arousal breathing which is actually what I expected to see given your history.
The flow rate preceding the arousal breathing does NOT look reduced too much, if any, so I don't think very minor flow rate reductions are the cause of the arousals. For the most part it looks like you were sleeping and then BAM an arousal.

That said....some of your breaths do look a bit flow limited when looking at the top of the breath. More on that later.

So you first have to learn to spot asleep breathing and then you look at the breaths immediately prior to the flagged event. If you have obvious blatant arousal breathing just prior to a flagged event then the event flagged is considered post arousal...and you weren't asleep.

Some examples below.

This example looks like you were asleep because there is evidence of asleep breathing prior to the flagged event but not much asleep breathing which is why I think that this one may be a sleep onset central. They aren't a big deal unless we see a truckload of them and I don't with you. I saw maybe 1 or 2 asleep centrals.



Here below are obvious post arousal flagged events. I circled the arousal breathing in red. They immediately precede the flagged event.









Now about flow limitations on the breathing itself.
See this chart for what normal and abnormal breaths look like.

[breathturn]

Thank you so much for the detailed analysis and explanations! I'm learning a lot.

Regarding the flow limitations, to my untrained eye my breaths look a little bit like the "Inspiratory flow limitation" example. Is that what you meant?

Based on what you said though, it sounds like the flow limitation is probably not the reason for my arousal events. Does that mean that my arousals are likely to be non-breathing-related?

[dataq1]

More likely than not.

[Pugsy]

Regarding the flow limitations, to my untrained eye my breaths look a little bit like the "Inspiratory flow limitation" example. Is that what you meant?

Yes...but we are now getting into data analysis levels that I am going to admit that I am not totally comfortable.
In other words we are pushing my own analysis skill levels.
You have an awful lot of normal breaths mixed in there as well.

Based on what you said though, it sounds like the flow limitation is probably not the reason for my arousal events. Does that mean that my arousals are likely to be non-breathing-related?

Again we are pushing my own skill levels here. My gut tells me that those minor changes in the flow rate breaths aren't responsible for the bulk of your arousals. My gut is right more times than it is wrong but I am the first one to admit that I am not perfect. You did have an in lab sleep study done if I remember right and they did mention a bunch of arousals but didn't tie all of them to your breathing. Am I remembering your history correctly? I don't have the time right now to go back over all your posts. I will try to find time to do a refresh on your history a little later today.

Which of course begs the question "if the arousals aren't caused by breathing issues then what is causing them" and we simply don't have anything to blame those arousals on.
You aren't taking any medications that might impact sleep quality as a potential side effect. That's always my first thought when I see sleep quality that can be said "it looks like a train wreck"....medication side effects is always first in my mind because it is so very common. No pain issues...no other health issues that we know of either.

[Pugsy]

More questions....some may or may not be relevant but we need to get a clearer picture of the behind the scenes thing.

How long have you been on the Finasteride and why?

How long have you been having problems with your sleep quality and the arousals?

Caffeine intake??? When and how much?

Do you do things that are "bad" in terms of good sleep hygiene? If so, how much?

[Rubicon]

Also the original sleep study w/o intervention that got you started down this road.

[breathturn]

Thank you all for the responses. I was hoping to spare you some of my long history here, but looks like we're getting to that point . Cue some nostalgic music and bear with me as we go on a whirlwind tour of my life...

Almost my entire life (at least going back to my pre-teens, my memory before that is less clear) I recall having trouble with tiredness, feeling bad in the morning, mild headaches all day, etc. But because I always felt that way, I got used to pushing through it and assumed that everyone felt the same (because it's so common for people to say they are tired), so I didn't think anything was particularly wrong with me. I naturally adapted in whatever ways I could -- sleeping on the bus to school, for example. Unfortunately, things slowly but surely got worse over the years. In college, I recall repeated issues staying awake in class, despite otherwise being an attentive student and sleeping 7-8+ hours a night. In my early twenties I started to get more and more awareness that something was not right with me: I was having the headaches all day, every single day (maybe 3/10 in intensity on average), tired all the time, and feeling absolutely HORRIBLE in the mornings. Although I started to suspect sleep was the culprit, I didn't have any direct evidence of it (I had very little awareness of waking up during the night, never had an experience of waking up choking/snoring or anything that would indicate breathing troubles), and I was not familiar with the various sleep conditions.

Finally around 2016 I started to hear more about the latest in sleep research, etc., and it all started to make sense to me. Sleep disturbances would be the perfect explanation for all the symptoms I was having, so I directly went to a sleep doctor for help (didn't even have a primary care at the time), and that's when my first sleep study was performed. I actually do still have some of the records from it -- I'll try to share those tomorrow. But they basically found that I had mild OSA, and didn't mention anything else. That's when I started my first trials with CPAP. I don't recall the exact lengths, but it was quite a bit (enough to meet the insurance's compliance requirements, and more). Over the next year or so it was basically just failed experiments with CPAP, with no improvement. In the following year I started to explore surgical options: the general feedback was that I had some moderate structural predisposition to breathing issues, but nothing super dramatic/obvious. More recently, I had a drug-induced sleep endoscopy, which showed no significant findings, and so the particular surgeon who did that does not recommend any surgery. My theory is that I probably didn't go into REM during the DISE, and they didn't get to see whatever the "real" issue is cropping up.
Some kind of surgery offered by other surgeons (e.g. palatal expansion) is still on the table for me, but I really hesitate to do it without any evidence that it will help, or in other words, any evidence that my sleeping problems are purely breathing-related. I did have a minor procedure to ablate my nasal turbinates, which helped my daytime breathing slightly, but didn't affect my sleep/symptoms.

As I mentioned previously, I also tried a mandibular advancement device, and many similar things (nasal strips, mouth taping, nasal sprays, etc.), never feeling improvement. This led me to start talking to other doctors, and exploring whether my problem could be caused by some other health issue, not sleep-related. Unfortunately, aside from my symptoms my bill of health is quite clean overall, minus a few chronic things:

- I'm prone to anxiety and have IBS (though it was much worse in the past and has mostly stabilized at this point after some gastro treatment), though honestly I think the bad sleep aggravates these rather than the other way around.
- My blood tests are generally very clean. The main outlier that shows up is elevated cortisol, which is no doubt tied to the terrible sleep...
- My lifestyle is about as "clean" as you can get, I think. I've never used a single recreational drug, drink very rarely, only take finasteride and vitamin D supplements, eat a fairly balanced diet... I have done short trials of many prescription medications in the past few years (working with various doctors, as discussed above) to try to help with my symptoms and/or sleep, but nothing has helped. I've always been on the skinny side, never overweight. Haven't always been great about exercising regularly, especially in my youth, but these days I do some moderate cardio 3-4 times a week (though the fatigue is making this harder and harder to maintain).
- I had an MRI of my brain which showed the sequela of chronic headaches, but no obvious cause.
- I have slightly elevated intracranial pressure, which again is possibly caused by the sleep problems.

I spent the past few years exploring the possibility of chronic migraines, but none of the many treatments/medications I tried for that helped me, so that seems unlikely at this point. Ditto with eliminating most of the other classic conditions that could explain headaches+fatigue (thyroidism, CFS, allergies, etc.), so all this inevitably led me back to looking at my sleep. The more I monitor my sleep, and the more I correlate my sleep with my symptoms, the more and more certain I become that it's a sleep problem. Hence why I started going back down the road of sleep medicine a while back, started BiPAP trials, etc. And now I'm here at 33

Unfortunately all this time my symptoms have been slowly but surely getting worse, as I mentioned before. These days, my headaches can go up to 5/10 or 6/10. Thankfully they stay in the mild-moderate range and never get too severe/crippling. The fatigue is the worst part: it's hard to make it through a day without needing to nap, and when that happens it could be anywhere from 30-120 minutes. The one thing that has gotten slightly better, for reasons I can't explain, is how bad I feel in the morning. Don't get me wrong, I still feel really bad, but I used to wake up (in my early-to-mid twenties) feeling like DEATH -- big headache, incredibly tired, world-is-ending sort of feeling. For whatever reason, that's gotten better in the past 5ish years. I can't point to any specific event that could have caused this improvement.

---

Hopefully I didn't bore you all to death with that. To answer some of the more specific questions that I didn't cover above:

- I've been on Finasteride for maybe 5 years or so, for hair loss. Because my problems far predate the finasteride, and I didn't see any difference when I started it, I don't think it's related to my issues.

- I drink a lot of tea (several cups per day), but I also am basically unaffected by caffeine (I did a genetic test a while back that confirmed as much). I just drink it because I like it, not for energy or anything like that (because it doesn't give me any anyways). I have tried to go without caffeine for a week or two before, just to see if it would help my sleep, but didn't notice any improvement.

- My sleep hygiene is not the greatest, but I wouldn't say it's catastrophic either. My main issues are that I get a ton of screen time and my schedule is extremely late shifted (going to bed at 4 AM or so). This kind of developed naturally over time because I feel the best late at night (probably because it's the farthest point in time from when I last slept...), and the worst in the morning. And because of my issues, it's very hard to keep a consistent schedule -- my body ALWAYS wants to sleep more. I can sleep 8,9,10,11,12 hours and still feel like I need more, so I have to fight hard against oversleeping/snoozing, and often lose...
I understand that there's a bit of a chicken-and-egg problem with sleep hygiene, and that better sleep hygiene could help me a bit, but I sincerely believe that there is a fundamental problem causing all of this independent of sleep hygiene. Backing that up, there have been times in my life where I had good sleep hygiene (e.g. if forced into a regular schedule by school/work) and felt very much the same.

- I tend to agree with the suspicion that most of my arousals are not breathing-related. I was adamant about this for a long time, given all the failed trials with PAP etc. Only recently did I circle back on this a bit, when I started to video record my sleep and see maybe ~half of the awakenings appeared to be caused by breathing issues. Now my money is on both breathing and other issues combined, with maybe the latter being more frequent (which would explain why I don't feel even a slight improvement when using PAP). In the recordings I do see some movements that seem odd to me: many of my awakenings come with a sudden shaking/jolting of the head, as if I was startled. Other times I see arm movements (arm hanging in the air or in awkward positions for a while, face rubbing, etc.).
The doctors have been really fuzzy about non-breathing issues. For a long time, the only thing they would ever mention in my sleep studies was the breathing, and that I didn't have PLM or RBD. In the more recent studies, and with my insistence, they did mention that my sleep wasn't great even when PAP was doing its job properly -- but they didn't really go into detail beyond that. When I have shown the sleep movement recordings to them, they don't seem too surprised and say it's not consistent with RBD or anything like that, and could still be related to breathing problems.

[breathturn]

...and here's my very first sleep study from 2016 (so naturally, no PAP/titration). Apologies for the quality, hopefully it's not too illegible.

[Rubicon]

Your diagnostic PSG showed O2 desaturation index 8.9 and AHI 14.9 so let's do xPAP.

Your therapeutic PSG showed O2 desaturation index 8.9 and AHI 0.0 so like WTF miracle is this?

For that matter, therapeutic PSG showed zero arousals and that's impossible.

We get real rest with N3, you need up to 20% of the night with N3 (it gets less as we age but that's sometimes due to a scoring technicality, holding on that for now). Anyway, your N3 for your age in both studies is terrible.

Here's a real problem:



Normal pCO2 is theoretically 40 mmHg. High normal is 45 mmHg. Given those numbers you have a significant underlying pulmonary/metabolic issue. You need electrolytes, ABG and complete PFT.

Alternatively, since O2 baseline sat is generally normal (pO2 should commeasurably drop with increasing pCO2, following the 130 rule) perhaps that's a major FUBAR.

So you have to consider additional possibilities:

Those guys are complete morons and have NFI what they're doing;

You don't have SBD worth treating and you're just making your sleep worse;

You need to see a good CBT-I sleep guy cause your sleep is a train wreck;

Unknown/undisclosed issue(s).

[breathturn]

Thank you Rubicon, I really appreciate your thoughts!

Your diagnostic PSG showed O2 desaturation index 8.9 and AHI 14.9 so let's do xPAP.

Your therapeutic PSG showed O2 desaturation index 8.9 and AHI 0.0 so like WTF miracle is this?

For that matter, therapeutic PSG showed zero arousals and that's impossible.

Yes, some of this was suspicious to me as well because I remember for a fact that I woke up quite a few times, so I have no idea what's going on with that data.

Normal pCO2 is theoretically 40 mmHg. High normal is 45 mmHg. Given those numbers you have a significant underlying pulmonary/metabolic issue. You need electrolytes, ABG and complete PFT.

Alternatively, since O2 baseline sat is generally normal (pO2 should commeasurably drop with increasing pCO2, following the 130 rule) perhaps that's a major FUBAR.

Very interesting, they never brought this up at all. I plan to ask my primary care about this next time we chat, and see if I can get ABG+PFT done.

So you have to consider additional possibilities:

Those guys are complete morons and have NFI what they're doing;

Yes, unfortunately I have had that feeling at some points... Sometimes it feels like they aren't actually looking at the data in-depth, rather they basically see some AHI and gloss over everything else.

You don't have SBD worth treating and you're just making your sleep worse;

This would be consistent with how I feel (slightly worse than normal when using PAP), and why I gave up on it for a while. I now have more evidence that I do have some amount of breathing problems, but that's no guarantee that most of my arousals are in fact caused by that, especially given the lack of improvement on PAP.

You need to see a good CBT-I sleep guy cause your sleep is a train wreck;

Possible, though this has been going on for so long and with so many different "versions" of my sleep hygiene over the years, that I feel like there *has* to be a more fundamental issue at play. I also fear that most of the techniques would not be so useful for me: I have no issues falling asleep / going back to sleep after awakenings.

The psychological angle is interesting more generally though. As I mentioned, I am quite prone to anxiety, and that's been sort of a lifelong thing. I believe the bad sleep is actual a catalyst for a lot of that, but it can certainly go both ways. Subjectively I do have the "racing mind"/brain going 200 mph experience occasionally, but I feel like my sleep issues have been so consistent throughout my life regardless of mental state that there had to be something physiological underpinning all this.

Unknown/undisclosed issue(s).

I believe that I have shared everything that could be relevant, but it's of course hard to be 100% complete. But you have my word that I'm not withholding information about any "bad" stuff along the lines of drug use etc.

[Rubicon]

Normal pCO2 is theoretically 40 mmHg. High normal is 45 mmHg. Given those numbers you have a significant underlying pulmonary/metabolic issue. You need electrolytes, ABG and complete PFT.

Alternatively, since O2 baseline sat is generally normal (pO2 should commeasurably drop with increasing pCO2, following the 130 rule) perhaps that's a major FUBAR.

Very interesting, they never brought this up at all. I plan to ask my primary care about this next time we chat, and see if I can get ABG+PFT done.

OK but get electrolytes too as if valid, that result could suggest metabolic alkalosis (the compensation for is reduced breathing).

Bring the above result and this graph along:



Since the NPSG guys are idiots, they probably don't know (or care) that DC devices need to be calibrated to the NPSG program. An xCO2 machine doesn't actually send the CO2 value to the program, it sends a DC signal (0.0 - 1.0 DCV). Calibration is accomplished by alternately sending 0.0 and 1.0 DCV signals from the CO2 device to the NPSG software before monitoring starts and adjusting the scale in the software. That calibration should be part of the graph but in your case it isn't.

In addition, xCO2 themselves need to be calibrated periodically with a known value of lab grade gas (usually 5.0% CO2) about every 6 months. Otherwise they may drift high (yeah aha moment).

Use above points to show you either got an underlying something or you're twice as knowledgeable than those "techs".

I suppose we could also be big about this. If you get a clean bill of health re: respiratory/metabolic status you could have your MD call up the NPSG guys and tell them they're not calibrating their CO2 devices or doing machine cals (2 separate things) and reporting ridiculous values.

IF we're going to be big about this...

[Rubicon]

But you have my word that I'm not withholding information about any "bad" stuff along the lines of drug use etc.

I know.

[Rubicon]

This a crude comparison of diagnostic and therapeutic NPSG. Looking specifically at sleep architecture and heart rate activity, IMO it doesn't make a difference whether you are treated or not:

Over the past few years, I've done many week-long to months-long trials of CPAP, and more recently BiPAP. Unfortunately, I have never felt better using either of those, and in fact, generally felt worse

Oh wait-- you already know that.

NM.

[Rubicon]

... caused by something like a mild form of REM behavior disorder or similar. I tried some medications that are typically prescribed for RBD, but unfortunately they didn't help.

Can you give all the details surrounding this including medications?

By "similar", did you mean

https://www.mayoclinic.org/diseases-con ... c-20375497