Challenges of Diagnosing Complex/Central/Mixed Sleep Apnea

[padster]

The number of people that follow their data must be WAY in the minority.

I thought that when I told these 10 people about being able to monitor and possibly improve their therapy, they would be interested in learning how but that hasn't been the case at all. Amazing!!

Yes, this is interesting but not surprising. There should be a lot more people wanting to actively take charge of trying to improve their health but sadly, the majority of them are content with leaving it entirely in their physician's hands. It would be interesting to see how many of these people would care about their data more if (i) they were educated about it and got over the mental block that the data is overwhelmingly complicated and that they couldn't make any difference even if they could interpret it (ii) there was better software or a data analysis service which made the information a lot more digestible to the average person.

He then sat for a hour explaining it all to me.

I'm interested to know if this is the norm or whether you were particularly fortunate with this doctor. I've certainly not had the opportunity to sit with a physician for an hour even in private hospitals. There's a book that talks about 'how doctors think' and how they're already thinking of how to get you out of the room after the first 5 to 10 minutes. It maybe an over-generalization but it's not far from the truth most of the time.

What we receive here on the forum is some pretty darn good advice based on experience.

Yes, it's wonderful. However, as you've highlighted, it's only a small minority of people who monitor their data, and probably even less who are forum literate (and have the time) to participate in trying to learn more about their condition and treatment. If the whole process was easier, a lot more people would be able to get the extra help that some of us are privileged to get.

When a problem defies the knowledge and experience of our most learned participants, referral to a physician is always recommended.

In contrast, I think a large number of physicians may not have the 'knowledge and experience of our most learned participants'. In the end, i suppose it's who you manage to see. When a physician recommended that i get a home sleep study, i asked about its effectiveness and mentioned that i had learned from an online resource that a Level I lab-based PSG was more accurate, he told me, "that's bullsh*t". I was shocked. Did he really believe what he was saying or was he just being defensive about having his suggestion questioned? Either way, his response was a poor reflection of his professionalism, or lack of. I was about to tell him that my source was a reputable CPAP forum with thousands of knowledgeable patients, but i refrained as there's really just no point with some people.

[padster]

Your average sleep doc, as a general rule, couldn't care less about treatment-machine data.

Seems like such a waste, there must be some use for some of the data.

He gives a diagnosis, he prescribes a pressure, then he's pretty much done.

This assumes that the gold standard PSG is a perfect (or at least an adequate) diagnostic tool … but PSG scoring is subject to interpretation and could lead to a mis-diagnosis (as Henry Jr pointed out). Doesn't this make it all quite an inefficient system (especially for non-standard OSA cases)?

It doesn't much matter if sleep labs vary in the details of the numbers--as long as the data is good enough to point to whether PAP should be tried.

Oh, okay, this would address the issue of how a perfectly scored PSG may be unnecessary for OSAs. If CPAP is the only option (surgery aside), then you may be quite right, all the PSG needs to do is indicate if CPAP therapy is required.

Home-treatment machines are not designed to give sleep-diagnosis info. So they don't. We may pretend to ourselves they do. But they don't. The fancy report sheets may LOOK like diagnostic results, but they aren't. Don't be fooled. Home-machine data is VERY valuable for checking leak and for trending. It isn't meant to be used any other way that I am aware of.

You're right. I think i should not have used the word 'diagnosis' in the original post as it has focused the discussion in the wrong direction. I was keen on exploring the possible ways in how better/more data from new home machines/equipment/systems could give patients (and their doctors) useful information about the progress of their condition and the effectiveness of their treatment.

But I wouldn't irritate him by shoving a bunch of printouts at him from my treatment machine unless he asked to see them.

Yes, shoving the printouts at him may be inappropriate, especially if he did not think the information was relevant. While CPAP data may be inappropriate for diagnosis, surely it does offer useful feedback on how a patient is progressing and responding to the treatment, so if a doctor is to get 'the full picture', wouldn't they need to take the CPAP info into account when assessing how the patient is doing, and what to do next?

You know it wasn't even until the most recent advancement in technology that we even got the added central data to our software reports from our cpap/apap machines.

The last few years...growing even faster as they refine the machines and what they can do and what they can report.
Makes me wonder what the machines available 3 years from now will show us. Maybe they will be of more use in the diagnostic realm and not limited so much to treatment realm.

That's a good way to look at it. To understand where we might be in the future, it's useful to reflect upon where the technology was in the recent past to get a better idea of the rate of progress and the direction which it may be heading.

[padster]

I am fairly certain that what we think we might want...has already occurred to the powers that build this machines and someone somewhere is working on it because they know that people will buy it. If there is a way to make more money...companies will build it.

The way things work now is that the big money is in the big business of diagnosing and prescribing. Since the manufacturers have to cater to that cartel in order to stay in the market and keep the consumer market from, uh, "influencing" the price of the machines too low, I doubt anything will be manufactured on purpose that could be seen as attempting to take the diagnostic process out of the hands of the pros any time soon.

Ahhh, but what if they do make something that makes the diagnostic part of things easier and better and more accurate for use at the sleep lab setting? I think it could filter down to home machines.

The pros will always vote for covering their own, uh, assets, when it comes to reserving diagnostics for themselves, if for no other reason than to prevent patients from self-diagnosing "medical conditions," and the system is such that the pros are the customers right now. That has to be fixed before the patient will start coming truly first.

Thank you both for this exchange. It was one of the things on my mind when making the initial post and jnk's feedback has clarified why the present system is not as efficient as it could be. Would be interesting to hear other opinions on this topic.

Ignoring the data collected by a CPAP machine because it's not as good as an in-lab PSG is like ignoring the results of a blood pressure reading because it's not as a $2000 nuclear stress test.

A doctor should consider all the available data.

Especially the data that's cheap to obtain, requires little effort from the patient, and gets taken every single night.

All you have to do is look a the data. If the data looks good, you have a large degree of confidence the treatment is eliminating the apnea without any further expensive testing.

If it shows a severe AHI, you probably need to do something right away. At least look at the data and see if you can see something and adjust the therapy. If that doesn't work, consider more expensive, intrusive, and inconvenient investigation.

If it shows mild problems, use your judgment. At least look for problems and maybe make some minor tweaks. Ask a few more questions of the patient.

Also, don't forget that the data shows number of hours of sleep/usage, sleep patterns, etc. All in objective form automatically recorded without counting on the patient's memory, honesty, and your effort to write it down.

That's what i thought. There's so much data from a CPAP machine that may be useful in helping to figure out exactly what's going on with a patient (especially those with borderline cases and more complex issues), it just doesn't seem right not to use it. Perhaps some of it may not be clinically significant, but surely, some of it will assist in giving clues on how to better understand a patient's condition and ways to improve their treatment.

If you are talking about those with things such as complex and mixed apnea the need for in home testing not limited to a single night or week of is much greater

I really believe the days of the "golden standard" super expensive single night in lab studies are limited indeed. I think they never gave a good view of “the average night” anyway (sleeping in a lab was never an average night for me anyways).

The whole diagnosis and treatment process needs to move into the home and be much less time limited (testing needs to be done over days, weeks, perhaps months to really see what is going on) for the sake of the person being treated. Data needs to be constantly gathered during PAP use, analyzed daily, and feedback provided to the person to note problems as they occur and lifestyle changes that would be wise. I believe that to do less than this is medically irresponsible, simply, and do indeed challenge the medical community to prove me wrong if they can by doing long term in home sleep testing research trials.

Hey Todzo, thanks for summing up a large part of what i was trying to say very succinctly and much more coherently.

http://ajrccm.atsjournals.org/content/167/5/716.full

Thanks John, that's a very useful reference and a relevant one to this discussion. Although it is only limited to OSA, there must be some comparable benefits for Complex and Central Sleep Apnea patients to get more involved in their therapy.

Self-adjustment of CPAP at home will provide equal or superior efficacy in the treatment of obstructive sleep apnea (OSA) as compared with in-laboratory titration.

This isn't so surprising if it's true that … "Lab titrations are done to titrate for worst-case scenario--supine REM in a strange environment. The idea is to prescribe a pressure that will be sufficient in that circumstance so that what happens in the patient's own bed, or in a motel, or anywhere else, is covered." … I presume this suggests that lab titrated pressures will be higher than what may be necessary in a patient's normal sleeping environment.

An educational model in which the patient is empowered with the understanding and ability to make decisions regarding treatment has been demonstrated to be successful in other medical conditions (16). We reasoned that a similar educational approach might be successful in patients with OSA who require CPAP treatment.

There's no doubt that it's not a good idea for the average patient to be 'tweaking dials and pushing buttons'. However, a large number of patients who are currently taking no part in optimizing their therapy will almost certainly be able to improve their treatment if they are provided with the information and confidence to do so IMO.

[jnk]

. . . While CPAP data may be inappropriate for diagnosis, surely it does offer useful feedback on how a patient is progressing and responding to the treatment, so if a doctor is to get 'the full picture', wouldn't they need to take the CPAP info into account when assessing how the patient is doing, and what to do next? . . .

My opinion is that a patient is likely to get a lot further with a doc by saying: "Ya know, Doc, I use my machine all night every night and have great sleep hygiene, but I'm still very, very tired all day and fall asleep constantly." Hopefully, the doc will think it is his idea that something may be off with the treatment pressure or response to treatment. If he does not ask questions along that route, then and only then, would I say: "I wonder if the events my home-machine is counting could be part of the problem?" Then I might produce from my pocket one folded up page showing a typical night (or one of my worst, if I were playing hardball), especially if it showed "clear-airway" events. I wouldn't explain the meaning of anything on the printout unless he asked, and I would play down my expertise and cater to his.

Yes, it is my health, but docs are people too, and they deal with a lot of patients who want to tell the doc what to do based on something they read from an alternative-medicine article on the Internet. Docs like to believe that their money wasn't wasted going to med school all those years, and it can make them more receptive to our input when we at least acknowledge their education and experience with how we phrase things.

Perhaps no one would do so directly, but fussing at a doc for ignoring our home-machine data is counter-productive in my opinion. Yes, the machine data may give hints that point in a direction for further exploration, but the doc has to defend what he does to the insurance bean-counters, and he has a protocol of some sort to follow to keep the office people happy. Half the tests he orders are just to cover his butt or to please insurance to prove he had a reason for doing what he did--a reason they respect.

To my mind, the OSA-test process is often mostly to please insurance.

So the trick is to be vocal. Telling the doc symptoms of residual daytime sleepiness and tiredness is likely to go a lot further toward his meeting the requirements of the insurance people for moving you on to a different machine--much further than a two-inch stack of home-machine printouts. He cares more about being accused of ignoring complaints from someone who may later fall asleep at the wheel then he cares about making a patient happy with his home-machine numbers.

In my opinion.

Even when we know what we know, we have to play THEIR game in how we go about it.

[padster]

Sorry, but I am just coming off a week where a friend's husband died unexpectedly during the night. He was slim and athletic but he snored heavily. Friend kept telling him she could hear him stop breathing in his sleep but he refused to do anything about it.

Now my friend will live maybe 30 more years without her life mate. Sad. Avoidable.

Sorry to hear about your friend's loss. It is very frustrating how the 99% will not listen to health advice unless it comes from white coats, and even more frustrating how a large number of white coats do not offer a lot of basic, affordable, obvious and lifestyle based advice to care for and improve people's health when they have so much power in their hands. It's especially frustrating when your loved ones question and doubt any well-intentioned suggestions, and opt for meds prescribed by doctors rather than trying to make lifestyle changes.

On the one hand, it's understandable how they're human in wanting to believe that a magical pill will solve their ailments, after all, it's a lot easier than trying to break life long habits. But it really is so frustrating not being able to help the people who are dearest to you, especially when the solutions are relatively straight forward (diet, exercise, CPAP etc) if they are only willing to listen/believe or at least just try (why won't some people even try!).

[Cereal Killer]

It is very frustrating how the 99% will not listen to health advice unless it comes from white coats,

Good post padster, but let me take issue with only this one statement. The large family practice that I utilize does talk to their patients about diet, exercise, alcohol, smoking, getting enough sleep and losing weight. Very, very few listen to the "white coats".

[DoriC]

I agree with everything jnk has posted. It is a game in some ways and as patients we have to learn the rules. It's all in the approach, unfortunate but true. With our Primary, I can question some of his advice in a "folksy"conversational tone and sometimes he'll actually change his mind based on my questions or at least explain to me why he wants to change something. With our Cardiologist, it's a different story, he's more reserved but really knows his stuff so needs a lot of "stroking"before I get the answers I want. Sometimes I go too far and he shuts down. Both admit they can diagnose OSA pretty easily but have no knowledge of the mechanics of the therapy. Our Pulmonary(sleep specialist) is very personable and patient and tries to "enlighten" me but the 2x we saw him, he was more interested in my explaining the data to him than the reverse. All the other non-medical recommendations he made about different masks, using machine 4hrs for compliance,etc, I had already learned in a few weeks on this forum so he added nothing new except to tell me to set the pressures wide open and "let the machine do it's job". He's excellent at treating my asthma and allergies and I rely on him for that myself.

[padster]

jnk & DoriC ... I totally agree with both of you, thanks for sharing your thoughts. There are so many games in life that we have to play already and it would be good if we didn't have to do the same with our lives/doctors. You really hit the nail on the head with your posts - namely that a patient should refrain from showing they know too much, should not be too direct in requesting for things and should slowly lead their doctor towards the end objective, all the time being very careful to nurse the doctor's feelings and ego. Reminds me a bit of getting a toddler to do what you want them to.

Cereal Killer ... Good to hear the family practice you use provides a well rounded approach, you're very fortunate.

[JohnBFisher]

... should not be too direct in requesting for things and should slowly lead their doctor towards the end objective, all the time being very careful to nurse the doctor's feelings and ego. Reminds me a bit of getting a toddler to do what you want them to. ...

Rather than thinking of it that way, the way I like to think of it is that I have a set of symptoms. I've certainly done some research - since I have the greatest vested interest in my situation - but I am hiring the doctor to be my consultant to help me sort out my situation. Thus, to not make the situation more confused than necessary, I need to clearly present my situation, the symptoms, any findings I have (statements of fact - not opinions). Once I've presented those facts, I can then ask questions ("From what I've read, this seems to indicate that ...."). But I don't want to state that this is obviously one situation or another. Let's face it, if I hired the correct consulting doctor, then he's seen FAR more cases than I have. I want to engage his intelligence and move things forward. I don't want to limit his examination. If I feel he's ignoring an important fact, I should raise that as a question ("Doesn't that ignore the fact that ...").

By the way, that's how I deal with my mechanic when I'm working or a difficult problem with my car. Or my plumber. Or my electrician. And it's the way I wanted the clients I helped to bring their computer problems to me.

Taking this type of approach helps to instantly build a TEAM that is more powerful because it taps into the strength of all members. It always places the person with this greatest vested interest in charge of the situation. It's perhaps not how many doctors want to work. But those that are good understand that the patient must be empowered to drive the therapy. It requires a LOT more than just a passive patient.

Though it amounts to the same thing, framing it in this manner will make a HUGE difference in how you interact with others.

[Chuck Connors]

When I first met my new sleep doctor, he said to me: "We're both smart guys. We'll figure this out together." Had I not been prepared in advance of meeting the doctor by educating myself with the help of this website and other resources, I likely would not have looked too smart in his eyes. It's never a good idea to try to give the doctor the impression that you know more than they do, but at least having a working knowledge of the issue goes a long way in letting the doctor know that you care about your own health. There is no doubt that we are our own best advocate. As most doctors are seeing 30 to 40 patients each day, you can do the math on how much time on average they are spending with each patient. Having the most productive 15 minutes that I can with the doctor is definitely a priority for me. For me, being well prepared for an appointment is asking good questions and actively listening. -Chuck-

[pharm30]

It's alarming to read that two techs can score a sleep study differently.
Suz

This is funny. I was diagnosed with complex sleep apnea last year.
I got a free sleep study through my fiance's work last Wed (results tomorrow).
The sleep tech looked at my previous studies and laughed. Said she had no clue why the tech did what they did during my titration.
Apparently I was only on CPAP for 8 minutes and they said I had "multiple" central apneas (3) before they switched me to Bipap and still had centrals.
According to study, I had 5 centrals in 3 minutes, 7 centrals in 20 min with increased pressure, and 5 in 10 minutes increased.
Confused tho - why I got diagnosed with Complex SA when my obstructives were 0?

Anyway, I get my results from just sleep study (no titration/machine) on Tues.

[Xney]

This is funny. I was diagnosed with complex sleep apnea last year.
I got a free sleep study through my fiance's work last Wed (results tomorrow).
The sleep tech looked at my previous studies and laughed. Said she had no clue why the tech did what they did during my titration.
Apparently I was only on CPAP for 8 minutes and they said I had "multiple" central apneas (3) before they switched me to Bipap and still had centrals.
According to study, I had 5 centrals in 3 minutes, 7 centrals in 20 min with increased pressure, and 5 in 10 minutes increased.
Confused tho - why I got diagnosed with Complex SA when my obstructives were 0?

Anyway, I get my results from just sleep study (no titration/machine) on Tues.

You get diagnosed with complex sleep apnea (usually) if you

a) have obstructive sleep apnea with no treatment
b) CPAP/bipap removes the OSAs, but...
c) central sleep apnea shows up (>= 5 AHI, 50%+ of apneas are central) once the OSAs are treated under pressure

You get "mixed" sleep apnea if you

a) have obstructive sleep apnea AHI >= 5
b) have central sleep apnea AHI >= 5

That's my understanding, anyways.

So if you had obstructives which the CPAP/BiPAP were treating and then centrals showed up, you could be put into that "complex" bucket.

However, it's pretty common to have centrals when you start sleep apnea treatment, so usually they're ignored in your early sleep studies when they start out. Sleep techs will not normally score "central apneas" which are a result of sleep transitions, moving around, etc.

[pharm30]

This is funny. I was diagnosed with complex sleep apnea last year.
I got a free sleep study through my fiance's work last Wed (results tomorrow).
The sleep tech looked at my previous studies and laughed. Said she had no clue why the tech did what they did during my titration.
Apparently I was only on CPAP for 8 minutes and they said I had "multiple" central apneas (3) before they switched me to Bipap and still had centrals.
According to study, I had 5 centrals in 3 minutes, 7 centrals in 20 min with increased pressure, and 5 in 10 minutes increased.
Confused tho - why I got diagnosed with Complex SA when my obstructives were 0?

Anyway, I get my results from just sleep study (no titration/machine) on Tues.

You get diagnosed with complex sleep apnea (usually) if you

a) have obstructive sleep apnea with no treatment
b) CPAP/bipap removes the OSAs, but...
c) central sleep apnea shows up (>= 5 AHI, 50%+ of apneas are central) once the OSAs are treated under pressure

You get "mixed" sleep apnea if you

a) have obstructive sleep apnea AHI >= 5
b) have central sleep apnea AHI >= 5

That's my understanding, anyways.

So if you had obstructives which the CPAP/BiPAP were treating and then centrals showed up, you could be put into that "complex" bucket.

However, it's pretty common to have centrals when you start sleep apnea treatment, so usually they're ignored in your early sleep studies when they start out. Sleep techs will not normally score "central apneas" which are a result of sleep transitions, moving around, etc.

As far as I can tell, I had no obstructives during diagnostic analysis (3 centrals, 51 hypopneas in 140 min) or during treatment, only centrals and hypopneas.
I was also originally titrated with a nasal mask, and I am a mouth breather who uses a FFM.
The tech from last week also mentioned they don't normally score "central apneas" as well....so I'm confused...AGAIN!

[Xney]

As far as I can tell, I had no obstructives during diagnostic analysis (3 centrals, 51 hypopneas in 140 min) or during treatment, only centrals and hypopneas.
I was also originally titrated with a nasal mask, and I am a mouth breather who uses a FFM.
The tech from last week also mentioned they don't normally score "central apneas" as well....so I'm confused...AGAIN!

(most) Hypopneas are "obstructive" events so they count the same as an obstructive apnea, basically.

A lot of "central apneas" really aren't, because you're moving in sleep, going between sleep stages, etc. That's why the techs say they don't score them usually. (note: some sleep clinics incorrectly don't score them)

In other words, if the tech is watching your brain waves, and at the same time your brain waves change, you stop trying to breathe for a bit, that's not a true central apnea. That's you changing sleep stages and during it you stopped breathing.

If you are just sleeping, stop trying to breathe, then 10 or 20 seconds later you "wake up", start breathing again, THAT is a central apnea. Some people start having them when they start getting CPAP treatment, and that's complex sleep apnea.

[pharm30]

so I got my results...The sleep MD thinks the tech pretty much messed up my previous studies.

He thinks it is ridiculous that I have an ASV machine, I only had sleep onset centrals.
I had few obstructives and hypopneas on my back and basically no events on my right side.