what my doctor said (re: AHI, centrals, pressure)

I had a post-titration-study appointment with my doctor today--mostly, I guess, so he could explain the study's results with me and see how I was doing with my new BiPAP and settings. After seeing my notebook full of printouts from Encore and the list of questions I had, the nurse who checked me told me, "Oh, he'll like that."

I think he genuinely did, too. He wondered where I got the notebook and all the printouts, so I told him. Even mentioned cpaptalk.com. And I didn't hide the fact that I was judiciously trying different settings. (I was titrated at 14 / 11, and right now I'm at 15 /12. Adventurous, aren't I?) I don't know what he thought about my buying my machine so I could own it rather than renting it through the prescribed DME, but at least that showed him how serious I was about my therapy.

It wasn't as long an appointment as I'd it'd be, but these are some things I got out of it.

1. Pressure. He pointed out how much better I did at 14 /11 than I'd done at lower levels (without CPAP at all, my numbers are bad, very bad), but he didn't seem bothered by my changing pressure to 15 / 12. He said as long as I could tolerate the higher pressure, it'd be fine. (He didn't say anything, really, about my two nights on Auto.)

2. AHI. He pointed out that I'd had an AHI of 2.1 during the three-hour portion of the titration study I'd spent at 14 /11. Looking at my current numbers, he said that anything under 5.0 AHI was normal, that he wouldn't worry about getting down to zero or 1.0. I came home to fortomorrow's post about giving up chasing 0 AHI, and I wondered what Den and rested gal would say about the "under 5 is fine" statement. I do feel better now--more energy, less irritability--but I wonder how much better I'd feel if I were consistently in, say, the 2.0-2.5 range, or just under 3.0 AHI, for that matter. But he wasn't too worried that my current average over just under 40 days was 5.6 or so. (That does contain two really crazy bad nights, but generally my AHI is between 4.0 and 7.0, and sometimes less.)

3. Centrals. I wish I could have talked to him more about this. The night of my study, I had 147 centrals, and no obstructives. I asked if it's something I should be concerned about, whether I might need a different machine at some point. He said nobody really knows what causes centrals, and that sometimes, after enough time on xPAP, they disappear. (I'd love to hear what ozij, SAG, -SWS, rested gal, and others have to say about this.)

Things I didn't get to talk to him about, because I either forgot or didn't have enough time, are flow limitations, silent flow limitations, and variable breathing. I did ask him about the connection between Central Serous Retinopathy and OSA, but while he was curious about that, I don't think he knew anything regarding the connection. (I just got an article about the CSR-OSA connection via interlibrary loan, and I may summarize it in a thread after reading it.)

We both agreed that I need to exercise more and lose weight, and he pointed out that a weight loss might very well lead to a different titration setting. (Yes, carbonman, the Bridgestone RB-2 and I need to become reacquainted--after the snow and ice are gone!)

Anyway, that's how the meeting went. I may have a new sleep doctor next year since we're changing HMOs, but it's possible I might be able to continue seeing this doctor. I like him, but I'm curious how a different doctor would approach my particular case, and what he or she would have to say to me.

This is also the first time I've really talked to a doctor about all this. After my first PSG and the subsequent titration study, I think I talked only to my primary care physician, not a sleep specialist. I know it's not easy (and maybe impossible) to judge a doctor from a distance, but if anyone has any take on what I've said here about the appointment in general, or what the doctor said in particular, I'd be glad for the feedback.

OH. After the appointment, I asked Sadie, whose title I don't know, but who seems to be the keeper of the masks and other such paraphernalia, if I might be able to get a Mirage Ultra II since I got sent home from the titration study with a Mirage Micro, which I don't really like. She remembered me because I told her I'd been using my current Mirage Ultra for years, with the same seal though different headgear. (Until joining this forum, I'd never have thought about hoarding masks. . . .) Anyway, she led me to a cart, from which she lifted a cloth cover to reveal an array of masks as tempting as appetizers or desserts in a four-star restaurant. And, bless her heart, she handed me a Mirage Ultra II.

I wonder what my leak rate will look like tomorrow morning. . . .

nath

nightjar wrote:. (Yes, carbonman, the Bridgestone RB-2 and I need to become reacquainted--after the snow and ice are gone!) nath

nath, so good to hear a positive doc report.
That is great that he supports YOU being in charge and
taking care of YOU.
Congrats!!

I had never heard of Bridgestone, so I looked it up....
I like the RB part....you got that right.

Riding a bike is much like cpap,
many good thing happen as a result.
It's good for mind and body.
Edit: ....come to think about it, the two of them together,
really make life sweet.

So, I'll be seeing you on down the road. COOL!!

nightjar wrote:I wondered what Den and rested gal would say about the "under 5 is fine" statement.

I can only speak for ME, but I don't think I could handle many nights over 3.0 for very long......but everything is relative and each of us is different.
I've had some nights that I didn't sleep worth a darn and ended up with 0.0 and then had other nights at 1.5 - 2.5 when I felt good the next day. But, these days, I seldom go over 1.0......I think I did one night in November.


Den

nightjar wrote: AHI. He pointed out that I'd had an AHI of 2.1 during the three-hour portion of the titration study I'd spent at 14 /11. Looking at my current numbers, he said that anything under 5.0 AHI was normal, that he wouldn't worry about getting down to zero or 1.0. I came home to fortomorrow's post about giving up chasing 0 AHI, and I wondered what Den and rested gal would say about the "under 5 is fine" statement. I do feel better now--more energy, less irritability--but I wonder how much better I'd feel if I were consistently in, say, the 2.0-2.5 range, or just under 3.0 AHI, for that matter.

Nightjar, your doctor's comment of any AHI under 5 being acceptable seems to match the status quo opinion in sleep medicine these days. Still, there are more than a few posters on this message board who claim to feel better getting AHI under 3.

nightjar wrote:Centrals. I wish I could have talked to him more about this. The night of my study, I had 147 centrals, and no obstructives. I asked if it's something I should be concerned about, whether I might need a different machine at some point. He said nobody really knows what causes centrals, and that sometimes, after enough time on xPAP, they disappear.

That seems to match what some patients have reported on the message board over the years, nightjar. That observation also seems to match up with this paper that we briefly discussed in a couple threads: http://www.aasmnet.org/JCSM/Articles/040502.pdf

Anyway, your doctor sounds open minded about allowing you to take control of your therapy. If you had only central apneas during your titration, then you're probably receiving some currently with that residual AHI that often dips above 5. If your residual AHI continues to stay high, then you might request another sleep study to see of you are experiencing CSDB/CompSA type symptoms. It sounds as if your doctor is waiting to see if your AHI settles down a bit.

carbonman wrote:Riding a bike is much like cpap,
many good thing happen as a result.

Yep, I really need to get on that RB-2. She's a 1992, 58cm (roughly), with Ishiwata tubing; I removed the Shimano derailleurs that came with it and put a set of SunTour Cyclone derailleurs on it, some old SunTour bar-cons, a Sugino AT triple, and a Nitto moustache bar. I do feel better when I ride, that's for sure.

Wulfman wrote:

nightjar wrote:I wondered what Den and rested gal would say about the "under 5 is fine" statement.

I can only speak for ME, but I don't think I could handle many nights over 3.0 for very long......but everything is relative and each of us is different.
I've had some nights that I didn't sleep worth a darn and ended up with 0.0 and then had other nights at 1.5 - 2.5 when I felt good the next day. But, these days, I seldom go over 1.0......I think I did one night in November.

Den

I need to keep a better sleep journal. I was doing well the first two weeks, and then I got lazy, probably partly because I had all that data. But I need to keep track of how I feel each day--how much energy I have, how clear my thinking is, how irritable I am, and anything else about my mental or physical state--and what I do each day--what I drink (as in beer, bourbon) and when, how much coffee I drink in the morning or early afternoon, and what I do for exercise, etc. I want to be able to see a correlation in my AHI, behavior, and mental and emotional states. (I know exercising regularly will help. It figures, though, that winter's here, and my big exercise plan involves shoveling and snow-raking. Maybe I'll buy some snow shoes. . . .)

In general, I really have felt better with the new machine. But I'm pretty sure I feel better when I have an AHI below 5.0, and especially when it's below 4.0. (I wish I could say below 2.0, but I've been in that territory just two nights, I think.

An AHI of 5.0 is way better than what I'd been experiencing, I'm sure. But it still seems high. I've been trying to placate myself by noticing large chunks (say 3 hours, give or take) when I had very few events, or none at all. That happens fairly often, and I do think I feel better after nights with big chunks of sleep like that.

But I'm curious what others think about the "anything under 5.0 AHI is normal and okay" idea.

I agree, though, Den: everyone is different. I'm also pretty sure I'd feel better if I continued to modify certain behaviors and achieved better AHI numbers--but those two things are harnessed together like a pair of fine Belgians. . . .

-SWS wrote:

nightjar wrote:Centrals. [. . .] He said nobody really knows what causes centrals, and that sometimes, after enough time on xPAP, they disappear.

That seems to match what some patients have reported on the message board over the years, nightjar. That observation also seems to match up with this paper that we briefly discussed in a couple threads: http://www.aasmnet.org/JCSM/Articles/040502.pdf

Anyway, your doctor sounds open minded about allowing you to take control of your therapy. If you had only central apneas during your titration, then you're probably receiving some currently with that residual AHI that often dips above 5. If your residual AHI continues to stay high, then you might request another sleep study to see of you are experiencing CSDB/CompSA type symptoms. It sounds as if your doctor is waiting to see if your AHI settles down a bit.

Thanks for the link to the article; I think I missed that thread--or got distracted by my not-quite-four-year-old! Anyway, I'll read that article now, for sure, and I'll also check out the other things you mention.

I've been thinking that some of my events were almost certainly centrals. I'm glad I've got a database and a notebook full of details I can show to whichever doctor I wind up seeing in the future. I do like the fellow I saw today, and I'm glad to know he's okay with how I'm handling my therapy.

nath

Glad to hear that you came away from your visit feeling positive and that your doctor and his staff seemed to appreciate your commitment to making your therapy work.

As to the oft elusive super low AHI, there's so many variables it's probably like comparing apples to oranges. Besides the number of events, the time spent in apnea, how low your oxygen goes, and if they cause arousals have to be considered, and not all that can be discerned. If I had to choose between having an AHI of 5 (times 8 hours sleep = 40 per night) with each being 15 seconds and causing no arousals, in regards to daytime symptoms, I would think that would be preferable to an AHI of 2 with those 16 events each lasting over 30 seconds and causing arousals.

Of course, if there are few to no events with minimal time in apnea, why not shoot for that? Easy for me to say, because I have had to make little effort since initially finding a therapeutic pressure, yet my AHI is consistently <1. Although it took me a long time to get consistent with my therapy, I grateful that part just came together for me. Hope you figure out how important it is to you and that your therapy reaches a point where you feel it is successful.

Kathy

kteague wrote:As to the oft elusive super low AHI, there's so many variables it's probably like comparing apples to oranges. Besides the number of events, the time spent in apnea, how low your oxygen goes, and if they cause arousals have to be considered, and not all that can be discerned. If I had to choose between having an AHI of 5 (times 8 hours sleep = 40 per night) with each being 15 seconds and causing no arousals, in regards to daytime symptoms, I would think that would be preferable to an AHI of 2 with those 16 events each lasting over 30 seconds and causing arousals.

Thanks, Kathy. I think I'll get there--probably not to 0-1 AHI, but to something that works for me.

It's funny thinking of all the things that work together to bring about successful therapy and good sleep. Just when I think I've considered almost everything that relates to my therapy, something else comes to mind.

It reminds me of why I never do anything but make a travesty of the game of golf: I'd think of all the things I needed to do to swing properly, and then, as the ball shot off the fairway, I'd remember something very important I'd forgotten. It just wasn't natural for me.

Anyway, I'm slowly figuring out bits and pieces of this process of achieving better sleep. Hopefully, when they'll all start to fit together. And it's not as if I'm not feeling better already: I am. But I know it's just a start, and that things will get even better . . . and that even the numbers might say so one day.

nath

nath, you're doing a great job! What a good doctor you have.

Even if you didn't get answers to all your questions, and you didn't ask everything you meant to, the doctor's (and his office staff's) attitude toward what you're doing is wonderful to hear about.

-SWS wrote:If your residual AHI continues to stay high, then you might request another sleep study to see of you are experiencing CSDB/CompSA type symptoms. It sounds as if your doctor is waiting to see if your AHI settles down a bit.

I agree.

kteague wrote:Besides the number of events, the time spent in apnea, how low your oxygen goes, and if they cause arousals have to be considered, and not all that can be discerned. If I had to choose between having an AHI of 5 (times 8 hours sleep = 40 per night) with each being 15 seconds and causing no arousals, in regards to daytime symptoms, I would think that would be preferable to an AHI of 2 with those 16 events each lasting over 30 seconds and causing arousals.

Good point, Kathy. There are "apneas", and then there are "APNEAS!"

nightjar wrote:Anyway, I'm slowly figuring out bits and pieces of this process of achieving better sleep. Hopefully, when they'll all start to fit together. And it's not as if I'm not feeling better already: I am. But I know it's just a start, and that things will get even better . . . and that even the numbers might say so one day.

Regardless of the numbers, here's how you'll know you have reached perfect treatment: One fine day you'll wake up and tell your wife, "Honey, I feel so good, I've decided I want to start doing ALL the housework, if that's ok with you."

That's when you know you've tweaked your treatment tooooooo well.

Congratulations, Nath, for finding a good doc (and for the good results, of course).
Biking is a very good way to exercise. Another good way is swimming.

About the AHI, Do you people think that the main concern of doctors could be the desaturation due to apnea,
and that they are less concerned about the sleep structure or vice versa? Just a wild thought.
I guess chasing the zero AHI might take means that break the sleep architecture: AHI/desat looks great,
but sleep is crappy.

At least in Finland the attitude seems to be strange: Everything seems to require a doctor, but the doctors
are not too interested in following up the treatment.

rested gal wrote:nath, you're doing a great job! What a good doctor you have.

Even if you didn't get answers to all your questions, and you didn't ask everything you meant to, the doctor's (and his office staff's) attitude toward what you're doing is wonderful to hear about.

Thanks, RG! It's good to see that the consensus is that I do have a good doctor to work with. I figure most folks here have more experience with these professionals, so I was interested in what y'all would think.

turbosnore wrote:About the AHI, Do you people think that the main concern of doctors could be the desaturation due to apnea,
and that they are less concerned about the sleep structure or vice versa? Just a wild thought.
I guess chasing the zero AHI might take means that break the sleep architecture: AHI/desat looks great,
but sleep is crappy.

At least in Finland the attitude seems to be strange: Everything seems to require a doctor, but the doctors
are not too interested in following up the treatment.

I don't know, Juha; maybe each doctor's focus is different. I think lots of them in the US are worried most about compliance. Mine was interested in that, too--he wanted to know if I was using the new machine every night (and of course I had evidence)--but he zeroed in on AHI right away, even before asking about compliance. My guess is that the thinking is that a low AHI means better oxygen levels. Then again, as Kathy pointed out, the time spent in apnea is important, too: more events that are shorter may be better than fewer events that are longer--longer apneas mean lower oxygen levels, after all. Maybe your doctor will turn out to be okay after all; but if not, it seems that there must be one that would be good, somewhere. Hopefully close to home!

rested gal wrote:One fine day you'll wake up and tell your wife, "Honey, I feel so good, I've decided I want to start doing ALL the housework, if that's ok with you." That's when you know you've tweaked your treatment tooooooo well.

HA! She'd probably start getting worried then. Truth is, about the only thing I don't do around the house is cook, and I don't think that would be a good idea; I expect there'd be a revolt of some kind--revolting food, anyway. . . . ;->

nath