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

[Pneumophile]

In that context, my wife (also a scientist) feels I'm being too harsh because it's a "real world" observational study and I'm asking for too much in the world of typical CPAP users. She is not a CPAP user btw. My take: observational studies are all very well and have their place in medicine - a lot can be learned. But here we already have evidence from earlier observational studies that CPAP might - repeat might - be beneficial. What the world needs now is a rigorous CV study with enough high-compliance CPAP users that the right analysis can be done (i.e. large enough sample size). Not another study like McEvoy.

[D.H.]

It's prevented heart attacks and strokes from slamming me. I am sure that I was headed that way before CPAP.

Of course, I have the good sense to use CPAP all night.

I'm pretty sure the same applies to me.

[Julie]

If you have a vision problem, please ignore this... but if not, can I suggest that trying to make a point with large purple writing is actually turning me off reading the messages? Not necessary... people will read what they want to read and bigger does not equal better. Yell at me when I don't have a hearing problem and I will make it a point to not listen at all.

[D.H.]

As a cardiac patient, this article almost ruined my day until I got to the 3.3 hours of use part. What a disreputable misleading article. If I had read this before I started on CPAP, I probably wouldn't have started treatment because I was not aware of the oxygen desats I was having. Now my oxygen levels are in the 90's all night. This article/study is flawed and misleading. Morning rant over...have a nice day everyone

Yes, a very misleading study. It needs to be shown whether the expected improvements occur in fully compliant patients. Assuming that is the case, then the real problem will be that non-compliance is a reason that some patients are not seeing the benefits. Once that is established, the doctors would know they need to address compliance issues much more aggressively.

[DreamStalker]

If you have a vision problem, please ignore this... but if not, can I suggest that trying to make a point with large purple writing is actually turning me off reading the messages? Not necessary... people will read what they want to read and bigger does not equal better. Yell at me when I don't have a hearing problem and I will make it a point to not listen at all.

WE HAVE A SOLUTION!!

[palerider]

If you have a vision problem, please ignore this

nah, vision problem is no excuse for posting stupid like that.

think about it, they'd have to increase the font size for everything to read, so there'd be no reason to post stupid like that, other than just being stupid.

another prime candidate for the foe list.

[kong]

. What the world needs now is a rigorous CV study with enough high-compliance CPAP users that the right analysis can be done (i.e. large enough sample size). Not another study like McEvoy.

I completely agree with you. I suspect that my regular use of CPAP (whenever I sleep) protects me from the cardiovascular harm of sleep apnea. I'd prefer to know that for sure and if it's not true, to know that as well. I'm not critical of the McEvoy study--it just doesn't answer the questions that I personally have.

.

[chunkyfrog]

Frankly, I can't help wondering WHO financed the study . . .

[Pap-Daddy]

"The Sleep Apnoea Cardiovascular Endpoints (SAVE) study monitored sleep apnoea patients with a pre-existing vascular disease over four years"

Seems like this could also be a case of closing the barn door after the horses have run off. For many (most?) of us here we likely had this condition for 5, 10, 20 years or perhaps longer untreated. Probably doing damage every night along the way that would be difficult or impossible to undo.

I don't need a study to show me that depriving your body of O2 for hours each nite year after year is not a good thing. Maybe there are those who do but I don't.

[kong]

Frankly, I can't help wondering WHO financed the study . . .

The people who make CPAP machines financed the study. http://www.nejm.org/doi/suppl/10.1056/N ... osures.pdf

Here is a link to the study: http://www.nejm.org/doi/full/10.1056/NE ... #t=article

The study dealt with people who either already had "coronary artery disease or cerebrovascular disease." The subjects did not experience daytime sleepiness. The study calls into question the normal treatment of those people with CPAP as a means of lowering their risk of having heart attacks and strokes. (The study noted several health benefits to CPAP; the news wasn't all bad.) Subjects used CPAP for an average of 3.3 hours per day. The study excluded people whose oxygen saturation was less than 80% for more than 10% of the night.

I'm not suggesting anyone stop using CPAP. I'd use CPAP even if it was certain that CPAP does help prevent heart attacks and strokes. I believe that CPAP, when used for whenever a person sleeps, probably does lower a person's risk of heart attack and stroke. I'd be more confident if there was a large, well-controlled study that proved the point.

[kong]

And why they chose the parameters they did remains a mystery.

Which parameter are you talking about? They only tested people without daytime sleepiness because they thought it was unethical not to provide CPAP to people who experienced daytime sleepiness. They only tested people with preexisting coronary artery disease or cerebrovascular disease; I believe the reason they did so was because it is easier to see an effect in this group than in the population as a whole. They excluded people who with severe oxygen desaturations; I believe they felt ethically compelled to do so because it would be unethical to withhold CPAP from the control group with severe desaturations.

I understand that the average CPAP treatment time was 3.3 hours, however, that's not a parameter the researchers chose. The patients did. The study obviously aimed to test ordinary CPAP use, not ideal use.

[palerider]

And why they chose the parameters they did remains a mystery.

Which parameter are you talking about? They only tested people without daytime sleepiness because they thought it was unethical not to provide CPAP to people who experienced daytime sleepiness. They only tested people with preexisting coronary artery disease or cerebrovascular disease; I believe the reason they did so was because it is easier to see an effect in this group than in the population as a whole. They excluded people who with severe oxygen desaturations; I believe they felt ethically compelled to do so because it would be unethical to withhold CPAP from the control group with severe desaturations.

I understand that the average CPAP treatment time was 3.3 hours, however, that's not a parameter the researchers chose. The patients did. The study obviously aimed to test ordinary CPAP use, not ideal use.

so, let's stick a cpap on people that aren't presenting any significant sleep apnea symptoms (EDS, oxy desats), and have them barely use it, (avg 3.3 hours) and then draw some specious conclusions and make some money.

[chunkyfrog]

Exactly, PR!
I am well aware that much "research" is conducted with the intent to result in predertermined results,
basically to confirm existing assumptions, and to collect grant money in return for the least possible effort.
One reason why the term "study" often elicits my suspicion.