Study: "CPAP machines do not reduce heart attack, strokes"

[Pneumophile]

I've been involved in large multicenter international trials (oncology),nincluding in China. On the whole these have been well designed and well executed studies with oncology centers that knew how to monitor compliance and follow effects on their patients' tumors and also follow side effects. This can be done without major problems, but evidently not in anprotocol like that in this research.

But this is a different type of study and perhaps should be held to a different standard. My wife (in the same line of work) tells me that the NEJM has been under criticism for mostly publishing large, very well controlled Phase III trials in which patient compliance is very closely monitored. So this paper may be an attempt to publish more "real world" type of clinical research, that asks a different type of question.

For the statistically minded I'm worried about false negatives or type 2 error in this study. This research is very vulnerable to type 2 errors.

[RobertS975]

The study was published online by the NEJM simultaneously with the presentation of the study at a medical conference in Rome. The results are what they are... some of the lead Australian researchers involved actually have been paid consultants by CPAP companies such as ResMed. The results of the study must now be interpreted and digested. But the greater lot of members of this board would rather insult, demean and disregard this study. People on this board are acting like their religion has been bashed. This reaction is common on this board... I once posted about the potential for hypoglossal nerve stimualtion with a small implanted pacemaker as a potential replacement for CPAP in the future, and was battered for it.

As I have said, I have about 850 days on my machine, and I consider my results to be a major positive in my life. I know I feel better during the daytime. And I know from my wife that I no longer snore. But I have no idea if CPAP will prolong my life or prevent other issues. Sleep apnea does not cause coronary artery disease as far as I can see. It is associated with coronary artey disease, diabetes, metabolic syndrome, hypertension etc IN PART because many of the same risk factors overlap.

If I had coronary artey disease, and sleep apnea, I would not want to stress my heart with 60 or 70 episodes of hypoxia a night! The results of this study did not seem to indicate any lowewr incidence of cardiovascular events in people with a history of vascular disease by using CPAP. Explanations for this result should be explored... study excluded patients with "severe" sleep apnea, study included OSA patients diagnosed with a home sleep study, limited average duration of nightly CPAP therapy etc.

A good percentage of patients who have been diagnosed with sleep apnea DO NOT treat it due to intolerance and other factors. And even larger is the number of individuals who obviously have sleep apnea but have never been tested. This study never says that CPAP is worthless. Actually, it goes out of its way to point out the benefits of CPAP even if this study, with its possible flaws in methodology, couldn't demonstrate an effect in preventing cardiovascular events.

Probably tilting at windmills, but please, everyone, keep your minds open. The history of medicine is replete with examples of things that were known for sure but turned out to be wrong! Good night... going to strap on my P10!

[Julie]

How about a fine line between 'preventing' MI's, strokes, etc... and just not seeing them as soon as we otherwise might... it's not quite the same thing. Prevention implies proaction, and maybe we can't do that well, yet anyhow, but while it might be extremely hard to prove that using Cpap x e.g. 10 yrs gave us 10 yrs in which we did not have MIs (because how do you prove imagined future problems in people without proven cardio. disease), is it so hard to tell ourselves using Cpap's a good idea, nothing much (relatively) to lose, etc. by using it?

[jnk...]

. . . would rather insult, demean and disregard this study. People on this board are acting like their religion has been bashed. . . .

I hereby insult the study. I hereby demean this study. And I most certainly disregard it. I consider that the only logical response.

If science is a religion, I believe the bashing of it was done wholly by the researchers who designed that study. Especially if they claim to have learned anything at all about CPAP by studying people who weren't actually using it.

For me, most important statement in the study is this:

. . . donations were provided by Respironics for the CPAP equipment and by ResMed for the sleep apnea diagnostic devices. None of the funding agencies contributed to the design of the trial, the collection or analysis of the data, the writing of the manuscript, or the decision to submit the manuscript for publication.

I have a feeling the manufacturers will insist on more robust methodology before donating in the future, since I doubt they were happy at all about the decision to submit this nonstudy.

[Pneumophile]

Don't forget to review the Supplementary Appendix,which is 80 pages long! There is a vast amount of info on methodology etc, including a section on assessing CPAP compliance (page 15). They did try to do that but what a challenge that must have been in all those sites in all those countries, often with staff unfamiliar with OSA treatment in the beginning. This is NOT your typical OSA study.

[Arlene1963]

Like it or not this study highlights an important weakness in the current gold standard treatment of OSA.

CPAP is not an easy therapy and in real life many folks just don't hack it. Sad but true.

If a prior heart attack or stroke isn't enough to convince someone to use this therapy then there really is a problem .... and if their doctors or nurse practioners are relatively unaware of CPAP and OSA and leaves it up to the "specialist" i.e. the sleep doctor who sees a patient once or twice only, then things get even more difficult for the OSA patient.

We see this here all the time, folks don't have a clue what exactly the therapy is about and they are left to sink or swim. That is how I felt until I got here to this forum and I will bet that many just abandon this treatment because they feel like crap anyway with a heart condition and why use a therapy if it makes them feel worse because of the myriad of issues we face when starting this therapy often with no support?

What a shame, and IMO this study reflects this mess. The current standard of medical treatment of OSA is very, very bad.

Unlike diabetes or BP where the family doctor or NP understand the numbers. My NP had no idea what AHI means and doesn't even want to talk about my treatment because she doesn't understand it. In fact she pretty much refuses to talk about CPAP with me.

I love my CPAP but yes, Resmed or one of the big players needs to come up with some other "gold standard" to treat OSA that will lead to better outcomes than 3.3 hours per night being considered treatment.

[chunkyfrog]

3.3 hours is sub-optimal. Far more SUB than optimal.
The parameters of the study were chosen to guarantee FAILURE.
This is a hallmark of JUNK SCIENCE or "study for hire",
where the outcome is predetermined to support an alternative "treatment".
As I suggested before, who sponsored this shameful excuse for science?

[Arlene1963]

3.3 hours is sub-optimal. Far more SUB than optimal.
The parameters of the study were chosen to guarantee FAILURE.
This is a hallmark of JUNK SCIENCE or "study for hire",
where the outcome is predetermined to support an alternative "treatment".
As I suggested before, who sponsored this shameful excuse for science?

LOL!! I wonder if Resmed or Respironics are set to introduce a brand new treatment for OSA to replace PAP therapy!

[Pneumophile]

Thank you for that insightful post Arlene. You have shifted the emphasis from rants about the evident failures of this massive study (from people like me) to the issue of non-compliance and its possible causes. If these authors had likewise shifted their focus and had tried to understand why compliance rates were so low - something they fully expected and indeed built into their study plan - perhaps the work WOULD deserve to be published in the NEJM.

Non-compliance in patients with a diagnosis of OSA, and indeed the unwillingness of people at high risk of OSA to get tested by polysomnography, are serious issues that can have fatal consequences. But this paper makes no real effort to address the problem that is so confounding to its central goal. And the reviewers for this paper missed an opportunity to really press the authors on the matter. What a pity.

[DreamStalker]

3.3 hours is sub-optimal. Far more SUB than optimal.
The parameters of the study were chosen to guarantee FAILURE.
This is a hallmark of JUNK SCIENCE or "study for hire",
where the outcome is predetermined to support an alternative "treatment".
As I suggested before, who sponsored this shameful excuse for science?

Looks like the Australian government and CPAP makers funded it ...

The SAVE study is made possible by donations and grants from study sponsor partners:

[chunkyfrog]

Considering that, I would EXPECT a follow-up study, to determine effective usage numbers and
how to best achieve effective usage time in more users--hopefully all of them.
Anything less would be irresponsible.

[DreamStalker]

Considering that, I would EXPECT a follow-up study, to determine effective usage numbers and
how to best achieve effective usage time in more users--hopefully all of them.
Anything less would be irresponsible.

I wonder if they will ever figure out that carbohydrate toxicity is what causes heart attacks and strokes.

[jnk...]

There is nothing wrong with the gold standard. That's why it is the gold standard. Sink or swim is the problem, not CPAP itself. Misinformation and disinformation about CPAP is the problem, not CPAP itself.

Blaming the victims helps nothing. And studies such as this one based on several misunderstandings of CPAP are part of that victimization and overall problem.

And in my opinion, repeatedly implying that 'maybe something better will come along soon' is part of the problem as well.

Just sayin'.

[Hang Fire]

implying that 'maybe something better will come along soon' is part of the problem as well

Death

[Hosehead4ever]

So basically, they're saying CPAP doesn't work without saying the patients weren't compliant with treatment.

That's like saying taking insulin doesn't prevent diabetic coma when you only take a third of the dose you need.

Well, duh! Of course it doesn't work if you aren't compliant with treatment.