Cognitive impairment - Could it be non-optimal CPAP?

[Marcman]

Over the last few months I've noticed increasing problems with attention, concentration, focus, and memory. So much so that I went to see a psychiatrist because I thought I might have ADHD or early onset Alzheimer's. I've seen the psychiatrist twice and on the last visit (yesterday) she had me take the Montreal Cognitive Assessment (MoCA) and the results were interesting.

I did extremely well on all parts of the test except for one, the memory test, and specifically, I had trouble with the "delayed recall" part where I was asked to remember 5 words, then a few other tasks were given, and approximately 5 minutes later I was asked to recall those words. I could not recall the words at all and even with hints (e.g.: "a color", "a flower") and even given multiple choices, I had great difficulty remembering the words. Her opinion is that the most likely cause is sleep apnea and that I should pursue optimizing my therapy, especially since there seemed to be some difficulty in finding a pressure that eliminated all of the respiratory events and during my second polysomnography/titration, my oxygenation dipped down to as low as 92% (or 88% if I look at the "wake" column in the table).

I am also waking up groggy and with a dry mouth most days and I have sometimes woken and noticed air escaping out through my lips, so I am starting to suspect that I might be mouth breathing.

Here is a report that I generated from the data on the SD card in my S9:



and an excerpt from my second sleep study/titration:



I'm already in contact with my sleep doctor and will likely schedule an appointment with him.

Some questions:

1. The 95th percentile for the leak rate is 19.2 - is that OK or is it too high?
2. The AHI is 2.3 and almost 80% of that comes from central apneas. I realize that 2.3 is a lot better than what I was pre-CPAP, but could that still be causing oxygen desaturations and could it be interrupting my sleep too much? I'm a little worried that the pressure is too high and it's causing the central apneas. On my initial study, I had only 2 central apneas (the longest being 19 seconds) -> a central index of 0.3. On the second (titration) study, I had 13 central apneas (the longest being 27 seconds) -> a central index of 2.1. In fact, just noticed that my apnea index is higher in the second study (2.7 vs. 0.9). On the other hand, the hypopnea index was reduced from 26.5 to 8.1 so that's good I guess.
3. The oxygen saturation of 92% - it seems that doctors worry when it dips below 90%? 92% is kind of borderline -- could it be contributing to my cognitive difficulties? In fact, in the polysomnography report, it says 92% was the minimum SpO2 during sleep; while awake (perhaps from an apnea event?) I actually had a minimum SpO2 of 88%, which in fact is the exact same minimum SpO2 that I had in my first polysomnography, performed with no CPAP. Another interesting factoid: one the first study I had zero oxygen desaturation events. On the second, I had 16, giving an index of 2.6. That seems most suspicious...
4. The minimum pulse rate of 33 - is that a cause for concern? My cardiac events table shows all zeros.

The more and more I look at the numbers, the more suspicious I am that things are not much better now than pre-CPAP (except that it got rid of my snoring). The doctor seemed quite satisfied after the second sleep study. And at the time I trusted his judgment. But now I'm not so sure that I should be content with how things are now.

I guess I'm wondering if CPAP is helping me but not enough?

[BlackSpinner]

with a dry mouth most days and I have sometimes woken and noticed air escaping out through my lips, so I am starting to suspect that I might be mouth breathing.

Right there is your biggest culprit. Mouth has to stay closed or use a full face mask.

[SleepingUgly]

I did extremely well on all parts of the test except for one, the memory test, and specifically, I had trouble with the "delayed recall" part where I was asked to remember 5 words, then a few other tasks were given, and approximately 5 minutes later I was asked to recall those words. I could not recall the words at all and even with hints (e.g.: "a color", "a flower") and even given multiple choices, I had great difficulty remembering the words.

When told the words, did you recognize them (e.g., "OH YEAH, it was daisy, right...")?

Her opinion is that the most likely cause is sleep apnea and that I should pursue optimizing my therapy, especially since there seemed to be some difficulty in finding a pressure that eliminated all of the respiratory events and during my second polysomnography/titration, my oxygenation dipped down to as low as 92% (or 88% if I look at the "wake" column in the table).

I don't know if 92% is a problem...

I am also waking up groggy and with a dry mouth most days and I have sometimes woken and noticed air escaping out through my lips, so I am starting to suspect that I might be mouth breathing.

Address that!

1. The 95th percentile for the leak rate is 19.2 - is that OK or is it too high?

Looks high to me.

2. The AHI is 2.3 and almost 80% of that comes from central apneas.

<5 is normal.

I realize that 2.3 is a lot better than what I was pre-CPAP, but could that still be causing oxygen desaturations and could it be interrupting my sleep too much?

You need an oximeter to answer whether you're desaturating.

I'm a little worried that the pressure is too high and it's causing the central apneas.

That's not a lot of centrals, and some/all of them could be related to arousals.

On my initial study, I had only 2 central apneas (the longest being 19 seconds) -> a central index of 0.3. On the second (titration) study, I had 13 central apneas (the longest being 27 seconds) -> a central index of 2.1. In fact, just noticed that my apnea index is higher in the second study (2.7 vs. 0.9).

Those are all (each) normal numbers. And there's night to night variability.

On the other hand, the hypopnea index was reduced from 26.5 to 8.1 so that's good I guess.

The INDEX on your titration was 8.1 hypopneas? So what was your total AHI on the titration?

3. The oxygen saturation of 92% - it seems that doctors worry when it dips below 90%? 92% is kind of borderline -- could it be contributing to my cognitive difficulties?

I don't think that's been studied, but if I had to give a wild guess, I'd say no.

In fact, in the polysomnography report, it says 92% was the minimum SpO2 during sleep; while awake (perhaps from an apnea event?) I actually had a minimum SpO2 of 88%, which in fact is the exact same minimum SpO2 that I had in my first polysomnography, performed with no CPAP. Another interesting factoid: one the first study I had zero oxygen desaturation events. On the second, I had 16, giving an index of 2.6. That seems most suspicious...

Night to night variability.

4. The minimum pulse rate of 33 - is that a cause for concern? My cardiac events table shows all zeros.

I have no idea. I don't even know if it's an artifact.

The more and more I look at the numbers, the more suspicious I am that things are not much better now than pre-CPAP (except that it got rid of my snoring). The doctor seemed quite satisfied after the second sleep study. And at the time I trusted his judgment. But now I'm not so sure that I should be content with how things are now.

Well, now I'm confused. What was your AHI on the titration? It looks fine now on your S9, except you're leaking too much, so I don't know how valid and interpretable that AHI is (your leaks aren't so horrendous, but they aren't ideal, assuming what you posted was representative). Look on Rescan at your leak lines and see if your leaks are caused by one or two big spikes and otherwise the leak line is pretty flat or has minor little blips, or whether it looks like the NYC skyline. The former is OK, the latter is not.

So far your brain seems just fine.

Are you on any medications that are new since the time you started experiencing the fogginess? Do you feel like you sleep soundly? Do you wake up refreshed in the morning? Does your FL graph look OK?

[avi123]

Marcman, you posted:

4. The minimum pulse rate of 33 - is that a cause for concern? My cardiac events table shows all zeros.


Reply:

an heart rate of 33 is at the minimum normal borderline for athletes.


Do you have a Pulse Oximeter like the following?

http://www.pulseoxstore.com/CMS-50E_INSTRUCTIONS.pdf


http://www.door2doorshop.com/wholesale/ ... ter-5.html

My pulse rate never went below 45 bpm. See my from two nights ago:

[ozij]

http://www.resmed.com/us/clinicians/com ... clinicians

[Marcman]

I did extremely well on all parts of the test except for one, the memory test, and specifically, I had trouble with the "delayed recall" part where I was asked to remember 5 words, then a few other tasks were given, and approximately 5 minutes later I was asked to recall those words. I could not recall the words at all and even with hints (e.g.: "a color", "a flower") and even given multiple choices, I had great difficulty remembering the words.

When told the words, did you recognize them (e.g., "OH YEAH, it was daisy, right...")?

So when she gave me several choices of flowers, I correctly recognized "daisy" as familiar. On the others, she gave me multiple choices and I could not recognize them.

Interestingly, a lot of my day-to-day troubles seem memory-related. For example, I think of something that I must do and then I go into another room and get distracted by something and then I can't remember what the first thing was. I also have a lot of trouble following lectures and conversations. The psychiatrist speculated that this could be because I can't remember previous things said well so it makes comprehension harder.

I am also waking up groggy and with a dry mouth most days and I have sometimes woken and noticed air escaping out through my lips, so I am starting to suspect that I might be mouth breathing.

Address that!

Yeah, I have a feeling that I'll have to ditch my Swift FX for a full-face mask. Not sure where to start with choosing a full-face mask. I guess I'll go to my DME and try a few on.

On the other hand, the hypopnea index was reduced from 26.5 to 8.1 so that's good I guess.

The INDEX on your titration was 8.1 hypopneas? So what was your total AHI on the titration?

Hypopnea index was 8.1. (I had 50 hypopneas). The apnea index was 2.7 (17 apneas). Total respiratory disturbance index was 10.8/hour. Here's the titration chart:



I remember that when I awoke from this study, the tech told me that she had a lot of trouble finding a pressure that would make all the disturbances go away. I think she was reluctant to go to 13 but then did so on the doctor's advice and then they ended up settling on 13. I remember that when I looked at this report, I was concerned that 13 was the last thing they tried and it was for less than an hour of mostly non-REM sleep, so I wonder if the fact that I only had 2 events is not a strong indication that this is a good pressure for me. I also noticed that when I was at 6 cm, I had only one hypopnea -- now granted this was in 22 minutes time, but that also makes me wonder why they raised the pressure. I am not a doctor or a CPAP technician, so I tend to think that there's a lot more to it than I understand and so I let the trained professionals dictate what's best.

Are you on any medications that are new since the time you started experiencing the fogginess? Do you feel like you sleep soundly? Do you wake up refreshed in the morning? Does your FL graph look OK?

No new meds. I've taken Zoloft (100 mg) for years, because I was diagnosed with depression in grad school in 1998. I fall asleep pretty quickly these days and I sleep like a rock. In my younger days, I think I took longer to fall asleep and slept less soundly. My wife often complains now that I don't wake up when our toddler cries even though the baby monitor is on my nightstand. It is also not uncommon that my wife wakes me and I might be up for 15 minutes or so with her calming my son and then in the morning I don't remember it. I have a fair amount of difficulty waking up in the morning. Morning is my favorite time for sleeping. Most of my life I've been a good student and successful in my career of software engineering. In the last few years, I've found my concentration, memory, and motivation fading. It could be any number of things from depression to apnea to aging (although I'm only  37) or a combination like apnea contributing to worsening depression. Unfortunately, the brain is hard to understand and measure.

Oh one more thing. I went to an ENT a few months ago and he said I had a deviated septum. I don't know if he qualified it as minor, major, etc. but I recall that he told me about the surgery for correcting it but didn't really push it. He told me about how the recovery is uncomfortable and then said it was up to me and I could do it if I wanted to and then sent me on my way with some Nasonex samples. I took this to mean that he thought it was a minor case and probably wasn't affecting me too much, but maybe he's just polite and doesn't want to be pushy. It's possible that a deviated septum could be contributing to mouth breathing and mouth breathing is reducing the effectiveness of the CPAP in which case I guess I should either get the surgery or just use a full-face mask.

[jedimark]

I have a similar problem.. all I can say it makes life miserable..

I call it fog.. I feel dumber, like I'm running at 10% capacity.. It comes with constant headaches.. They are not painful, but just dull enough to make me realize how much it sucks not being able to concentrate.. (MRI+CT revealed no obvious tumors, etc)

Finding words is hard.. Trying to have a conversion makes people think I'm weird.. I'm usually struggling to explain stuff.

I've forgotten if my memory was ever any good.. I'm like a goldfish in that regard.

Background noise frustrates the crap out of me, because I have such a hard time keeping a thought train from derailing.. I get cranky very easily..

Get the occasional burst of clarity, but it never lasts long enough.

No mouth leaks or major desaturations though.. My AHI is up and down.. Get scary looking PB/CSR with tons of events some nights, other nights, pretty boring.. I always get a reasonable number of Hypopneas.

[Marcman]

I wonder if I posted my detailed graph from ResScan, if it's possible to make an educated guess about whether I'm mouth leaking? If it looks like a likely problem, that might give me the inspiration to swing by my DME (SleepQuest) and inquire about full face masks.



Not good that I'm shooting over the red line in a few instances, but I am below the line most of the time. Interesting that I long periods of high leak rates with periods of low leak rates in between. Could that be because I tend to mouth breathe when I'm in a certain phase of sleep? (e.g.: REM?)

The statistics for this night say that the median leak rate was 1.2 L/min (not bad?), the 95th percentile was 24.0 (not so good?), and the maximum was 38.4. I had an AHI of 1.9 which broke down to 1.5 for central apneas, 0.1 for obstructive apneas, and 0.3 for hypopneas. My understanding is that an AHI < 5 is quite good and I'm encourage by the low number for obstructive apneas. It's a little strange that central apneas are the biggest part of my AHI -- I don't know if this is because the machine is causing me to have central apneas or because the machine gets confused sometimes and logs central apneas.

On one of the worse nights that I can find recently, leak-wise, July 6, I had a median leak of 2.4 L/min, 95th percentile of 31.2, and a maximum of 46.8. This is one of 8 nights in the last 28 nights where my 95th percentile was above the red line of 24 L/min. Graph:

[SleepingUgly]

Impossible to say where you're leaking, but based on my personal experience, if you are ABLE to breathe through your nose, I would look at other ways of keeping your mouth shut before moving to a full face mask. But that's just me.

[DoriC]

With that much leaking the AHI data is not really reliable.

[Roger2]

I am also waking up groggy and with a dry mouth most days and I have sometimes woken and noticed air escaping out through my lips, so I am starting to suspect that I might be mouth breathing.

By “Groggy” do you feel stunned or confused and slow to react or light headed?

When you are de-saturated to the mid 80’s when taken off oxygen, how long does it take your system to recover to 90% or so when on it again? If your recovery to at least 90% takes several minutes when you are back on oxygen then that could be an indicator of a cardiac problem.

As for a good saturation level, I have always been told by the technicians and physicians at National Jewish Hospital and Research Center in Denver that 90% is good. You need also to consider that oximiters are not totally accurate as they are all set to a national standard at the manufacturing facility and can be as much as 6% off either high or low. To determine that NJ usually does a blood gas and take an oximiter reading at the same time. That is considered as totally accurate (at least by them) and the blood gas is then compared to the oximiter reading. Mine used read 4% high as did theirs and the last time I dropped the instrument and sent it in for repairs; I mentioned to the factory that it was 4% higher than the blood gas. They were able then to set it to about 1% but doctors are not going to do that because everyone will be slightly different. Anyway, that needs to be considered if you are basing a saturation level to symptoms.

Now as for some of your symptoms, I too have some of those like the light headed or groggy feeling after a night on the cpap but then I was having those same symptoms before going on a cpap. They can also be caused by some of the medication you might be taking (as do I) and blood pressure medicine is many times the culprit. That of course you need to have your physician determine.

In my own case they are leaning to cardiac problems and perhaps you need to have that checked, particularly if you have a slow restoration level when taken off oxygen for en or fifteen minutes and then put back on it.

Lastly, those with a cardiac condition known as Atrial Fibrillation (AF for short) which is chronic almost always have obstructive sleep apnea (OSA). Before you begin to worry about that, not all with OSA have AF. In my own case I have had very mild OSA since it was first diagnosed by NJ in 2003 and my AF was intermittent and somewhat random. I wore a heart monitor on several occasions over the past few years and would have 15 to 30 AF episodes in a month. When I was hospitalized with pneumonia in May the AF went from random to chronic. That is what prompted my cardiologist to request a sleep study and that turned out to verify the relationship between AF and OSA. Shortly after that I tried the cpap for two weeks to see if I could adapt but there were not a whole lot of choices as I was given the machine and have been on it since, about a month now.

If you are unable to have your symptoms resolved, you might want to consider going to a clinic that specializes in those problems to get a team approach with the necessary experts working together to find out what is wrong and how to resolve it. It can be time consuming so patience is the byword here but I do recommend a team approach.

What do you mean by “cognitive impairment?”

Roger

[Marcman]

Thanks all, for the suggestions and ideas! I think I definitely at least to get a chinstrap or a PAPcap to try to keep my trap closed. I also think I might have ChinUp strips which I tried a while back and didn't notice enough improvement in a night or two to offset having to peel them off my face in the morning. I don't even think I wrote down when I used them or looked at my leak stats those nights, which was a big mistake in retrospect.

For the folks who asked about "cognitive impairment", I have a lot of trouble paying attention in meetings and conversations and I tend to miss a lot of information. I have pretty bad short-term memory, especially if I get distracted by something. I think most normal people if they are interrupted while doing something, probably can return to the original task very easily. I am really bad at that. If I hit a snag while doing something and encounter a new problem, that often leads to me doing a chain of things that are increasingly unrelated to the original problem. I also am sometimes zombie-like - I think this is most obvious when I'm not keeping busy (e.g.: trying to watch my son at Gymboree, boring meetings, etc.). It's like my brain kind of shuts off and become kind of sluggish. Some of this sounds almost like ADHD, except that an ADHD diagnosis requires that you had the symptoms since childhood, which I did not (my first depressive episode was around 1998 - I suspect that this might've been the beginning of the dulling of my mind). So "cognitive impairment" for me is ADHD-like symptoms and poor short-term memory and I am exploring the theory that my apnea diagnosed in September of 2010 (and who knows how long I had it undiagnosed) is not fully controlled by my CPAP treatment.

[SleepingUgly]

So "cognitive impairment" for me is ADHD-like symptoms and poor short-term memory and I am exploring the theory that my apnea diagnosed in September of 2010 (and who knows how long I had it undiagnosed) is not fully controlled by my CPAP treatment.

That makes good sense, and I am doing the same. After all, I'm reluctant to accept that I have early-onset dementia until I've ruled out the more likely causes for my cognitive impairments. Unlike you, however, my sleepiness has been going on so long that it will only be after I eliminate it (note the optimism) that I'll be able to see if there is any residual "ADHD" left. I certainly have ADHD-like symptoms now, just like you, but I was obviously not so impaired as a child that it came to anyone's attention (including mine). By the time I hit college, I was getting tired, so that's the more parsimonious explanation for why I had trouble paying attention doing sedentary activities such as reading textbooks for hours at a time.

[Muse-Inc]

Marcman, if it were me, I'd fix the leaks before making any other decisions about my therapy. As Dori said, with leaks that wild, the therapy numbers are suspect. I had to give up my beloved OptiLite pillow mask after almost 2 yrs as I started losing therepy air via loose lips. I now wear the RespCare Hybrid Universal mask with pillows and an oral cushion that means no losing therapy air and if needed I can breathe thru my mouth. Quite a few of us here wear it. It comes with 3 sizes of pillows and 3 sizes of mouth cushion so getting a good fit is pretty easy if you watch the DVD that comes with it or the online video. My leaks are typically "0" median, "0-2" 95centile, and max all over the place depending on how coordianted I am taking a breath & then pressing 'off' when I remove my mask. With numbers like mine, the leak line is virtually flat with a spike at the end. Before I fixed all my leaks, the wilder the leak swings, the worse I tended to feel the next day making me suspect that, at least in my case, the leaks were causing sleep stage shifts or micro-arousals. I seemed to sleep better if I had constant low-level leak rather than leak lines that resembled a line of skyscrapers.

A recording pulse-ox is a good idea for monitoring your O2 and pulse rate, then comparing it to your apneic events & leaks. This is the only good way to assess what's going on with those 2 while you sleep. Cognitive impairment is a bummer! Most of mine is pretty much gone. Still have some short-term memory issues, but I carry colored index cards for non-tasks and memory reminders, like grocery list, errands, things to get/do; at work, I have a smallish notepad that goes everwhere with me, my co-workers laugh and call it a 'Bible' as everything goes into it. While they chuckle, they still come to me to ask what that 'thing' was from a few days/weeks ago I laugh too saying there's nothing wrong with my memory, it's the memory retrival program that's not working so well. BTW, I take a lot of omega 3s, highest % is DHA for it's positive effect on brain function, cell-to-cell communications, help laying down new neural connections, and to help create new brain cells. That's in addition to the ton of other supplements I take, all to help my body & brain heal from the ravages of yrs of untreated apnea -- can ya guess I was labelled severe? My cognitive impairment was noticeable, especially verbal fluency...writing little affected but speaking was a struggle at time trying to say the right word, like " hand me the box" intending "hand me the pot." Went on for too many months...and I made my living as a technical writer until this year.

Good luck on resolving this.

[Roger2]

I've seen the psychiatrist twice

Has your psychiatrist made a diagnosis yet and if not what is her opinion concerning your symptoms?

Roger