IMPORTANT New Apnea Study

[Jere]

Do you have a link?

http://lewiston.mit.edu/sleep/ApneaNEJM1.pdf

[Dan01]

From the OSA study:

Several studies have demonstrated that airway pressurization (the main medical therapy for the
syndrome) can reverse hypercoagulability 34 35 and hemodynamic changes 38-42 and even reduce the risk of cardiovascular events.25 The present study was not designed or powered to address adherence with treatment or the effect of treatment on outcomes. Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies. Several explanations may account for this finding. First, it is likely that many of our patients had had untreated obstructive sleep apnea for years before seeking treatment, resulting in a prolonged
exposure to cardiovascular risk. The median 3.4 years of follow-up may not have been a sufficient length of time to derive the potential cardiovascular therapeutic benefits. Second, reduced compliance with continuous positive airway pressure and limited efficacy of other treatments may have played a role in the failure of therapy to reduce the risk to baseline levels. Third, in contrast to the patients in a recent study that suggested a beneficial effect of treatment on outcomes, 25 our population was older and had a higher prevalence of cardiovascular risk factors.

[Dan01]

Again. Their were too many variables in the OSA study. Also, it is likely according to the study that the younger you start therapy the better your chances.

[Dan01]

Thank you so much.

It appears they lumped all treatments together. I like the earlier studies that compared CPAP to non-CPAP better.

Sorry about that neversleeps.

The second study did compare CPAP vs. non CPAP more accurately. The biggest problem as I understand it is that when we stop breathing or blood pressure goes sky high. Then when we breathe it delines. This goes back and forth all night. It is this sudden change in blood pressure that makes stroke an heart failure / attacks so dangerous.

[neversleeps]

Hey Dan01, I'm sorry. I was getting pretty frustrated there, but I'm glad we're now all on the same page (literally!).

Many patients with the obstructive sleep apnea syndrome received some type of treatment for sleep apnea after the initial evaluation. Thirty-one percent achieved a weight reduction of 10 percent or more; 58 percent were using airway pressurization for at least four hours per night for five nights or more per week; 15 percent underwent upperairway surgery.

Several studies have demonstrated that airway pressurization (the main medical therapy for the syndrome) can reverse hypercoagulability and hemodynamic changes and even reduce the risk of cardiovascular events. The present study was not designed or powered to address adherence with treatment or the effect of treatment on outcomes.

Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies. Several explanations may account for this finding. First, it is likely that many of our patients had had untreated obstructive sleep apnea for years before seeking treatment, resulting in a prolonged exposure to cardiovascular risk. The median 3.4 years of follow-up may not have been a sufficient length of time to derive the potential cardiovascular therapeutic benefits. Second, reduced compliance with continuous positive airway pressure and limited efficacy of other treatments may have played a role in the failure of therapy to reduce the risk to baseline levels. Third, in contrast to the patients in a recent study that suggested a beneficial effect of treatment on outcomes, 25 our population was older and had a higher prevalence of cardiovascular risk factors.

What bugs me is that they say: "Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies."
You read that and you assume (because this is, after all, a scientific study) the participants on cpap therapy (mentioned in the first paragraph) must have been monitored in some way in order for them to reach the determination that cpap therapy was one of the various therapies that had no effect on stroke risk.

But if you read farther down, you realize they never even verified or monitored continued cpap use (if indeed there was any continued use by any of the participants for even 1 minute, let alone all their sleeping hours) throughout the course of the study: "Second, reduced compliance with continuous positive airway pressure and limited efficacy of other treatments may have played a role in the failure of therapy to reduce the risk to baseline levels."

Dan01, you're exactly right. What they should have done is eliminated lumping cpap therapy in with their "various" ineffective therapies, since they did not bother to obtain any data regarding cpap use (if any) for the duration of the study.

[Dan01]

I agree. The study was not meant to compare CPAP with non-CPAP use and then they threw in those lines with endless variables involved. It is dangerous because there may be some people that wont take the therapy because of it.

[Jere]

Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies.

Neversleeps -

The quoted language is the kicker in the entire study, but it is not necessarily incorrect. As I read it, all the researchers are saying is that some number within the study group (we don't know what number) used xPAP, but that by looking at the 700 members of the ENTIRE study group (including the xpaper's), there was still an increased incidence of stroke. This is not an indictment on xpap, merely an acknowledgement of one of the variables in the study.

However, if I were in charge of the study (everything would be better if I were in charge), I would have eliminated from the study group those who received treatment for OSA, whether xpap or anything else. These people would skew the results regardless of whether they did or did not stick to the therapy. Although it would have been easy to have disqualified xpaper's from the study group (along with the diabetics, etc. the researches did eliminate), my guess is that (a) the researchers could/would not stop people from seeking therapy over the study period and (b) it would have been difficult to amass a group of people with OSA who would agree never to seek therapy.

Given all that (including my pure layman interpretation of what I read in the study), the language remains subject to an interpretation that was probably not intended by the researches, but that could nonetheless dissuade doctors (the target audience) and patients from treating OSA.

[Dan01]

I think this article pretty much wraps up you the posters here has said

http://bestsyndication.com/2005/Dan-WIL ... y_CPAP.htm

[Guest]

Perfect Dan! Thanks for writing it! Now if we could just get the rest of the world to see it too!

[ozij]

Neversleeps
You are repeatedly emphasising parts of the research not , emphasised in the original text. And you are repeatedly pointing out this data that you choose to emphasise as though it were the most important thing in the research. It is not. That is one sure way of frightening people who don't take the time to read the whole research, or who do not understand how research is done.

The text emphasised by neversleeps is not the important stuff in this research. Anyone worried by it should either disregard it, or look for studies done about the effects of CPAP or Automatic PAP (APAP) on people who use it consisntently, all night, and for each nap

Please, neversleeps, I know you mean well, but don't emphasise a quote without making it very very clear what is the origin, and what you added to it.
O.

[ozij]

Dan01

Your "best" link
1. Has not one link to academic research the proves how helpful CPAP is.
2. Says that CPAP is proven treatment for many ailments,
And:

3. Has a number or commercial links to sellers of CPAP and other sleep treatment.

That "article" is an infomercial.

Which is why I will not post on this thread again. No need to send more readers to infomercials. Hopefully other well meaning people will follow my lead.

O.

[rested gal]

What bugs me is that they say: "Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies."
You read that and you assume (because this is, after all, a scientific study) the participants on cpap therapy (mentioned in the first paragraph) must have been monitored in some way in order for them to reach the determination that cpap therapy was one of the various therapies that had no effect on stroke risk.

That is exactly what bothers me about this study, too, never sleeps.

Their definition of treatment (indeed the entire medical/insurance communities' definition of "treatment") regarding CPAP treatment is not at all what I would call real "treatment." Real CPAP treatment is a person using the mask and machine far more consistently than just averaging 4 hours per night, 5 days a week.

Even so... even if one accepts 4 hours/5 days a week as being "cpap treatment", the researchers conducting this study said:
"The present study was not designed or powered to address adherence with treatment or the effect of treatment on outcomes."

Not addressing adherence with treatment = not knowing if the subjects on cpap were even using their machines at all. That astounds me. Those researchers didn't even know if over half the subjects in their study continued to use cpap treatment AT ALL during a study than spanned over three years of time!

Yet the researchers go on to conclude this!!:
"Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies."

despite the administration of various therapies

Think about that folks... most of the people (58% of the subjects in this study) were supposedly on cpap treatment. How many of them were using it only 4 hours a night? Worse, how many of them had stopped using their cpap machines entirely during those three years? The researchers kept speaking of "treatment" and "therapy", but how many of their so-called cpap subjects were even using cpap AT ALL throughout this study?

Granted, the researchers included several explanations for their "finding", one of which was:
"Second, reduced compliance with continuous positive airway pressure and limited efficacy of other treatments may have played a role in the failure of therapy to reduce the risk to baseline levels."

heheh..well.....if "reduced compliance" means even less than the already pitifully inadequate (imho) standard of 4 hours a night....
The most common estimate of drop out rate among cpap users is that 40% stop using their machines. If almost half (40%) of the majority (58% of the "treated" subjects in this study) weren't even using cpap AT ALL during the study, yet were being counted all along as receiving "treatment"..... sheesh.

I'm very glad that never sleeps has continued to point out the problems with this particular study.

Many doctors are not very well informed about sleep apnea in the first place. Why should they get concerned enough to find out more when they see words like this in the conclusion of this particular study:

Nonetheless

our study demonstrated

increased risk

despite

various therapies

(bold emphasis mine)

To me, the frightening thing is the way the researchers stated their "Nonetheless" statement, and the way many doctors and cpap users will take it. What's the use of prescribing a sleep study or encouraging a treatment that most patients really don't want -- cpap treatment -- if patient is still at risk? From the reluctant patient's perspective...What's the use of putting up with inconvenience and mask discomfort if I'm still at risk?

I think never sleeps is right to emphasize the shortcomings in that study. Would have been better to put an "emphasis mine" thingy in the post, but that's a minor quibble in my mind compared to the service never sleeps is doing by bringing out the problem with the way those researchers defined, studied, and drew conclusions about people who received "treatment" for OSA.

[Guest]

Dan's article is a bit thin on the sources and is clearly an infomercial. A bit disapointing.

[Guest]

Yet the researchers go on to conclude this!!:
"Nonetheless, our study demonstrated an increased risk of stroke or death from any cause among patients with the obstructive sleep apnea syndrome despite the administration of various therapies."

Keeping this thread in the spirit of a debate and not a personal attack on anyone , I really don't think that the researchers came to any kind of "conclusion" regarding the efficacy of xpap. They raise the issue only to say that some people in the study underwent some treatment for OSA, but that nonetheless the OSA/stroke risk exists. They make no 'conclusions' about xpap or any other treatment, other than to say that the OSA/stroke link is evident even though some people among the 700 people in the study were under some form of OSA treatment. In legal parlance, the "nonetheless" sentence is a 'qualification' of the true conclusion of the study, namely, that OSA = increased stroke risk.

Like I said before, I don't understand why the researchers did not exclude xpap-ers from the study. They certainly skew the results. My guess is that the incidence of stroke would have been significantly higher if no one in the study was receiving xpap treatment. That seems to be the true flaw in the study and would have provided a genuine baseline for the next study, which would be to test non-xpap users against xpap users. That is the test I would like to see.

[Jere]

Drat - Forgot to login - the one just above is mine .