Reduction of "sleepiness" on cpap real or placebo effect?

[johnthomasmacdonald]

just came across this study:

Thorax. 2012 Oct;67(10):920-4. Epub 2012 May 26.

The effect of continuous positive airway pressure usage on sleepiness in obstructive sleep apnoea: real effects or expectation of benefit?
Crawford MR, Bartlett DJ, Coughlin SR, Phillips CL, Neill AM, Espie CA, Dungan GC 2nd, Wilding JP, Calverley PM, Grunstein RR, Marshall NS.
Source
Sydney Nursing School, University of Sydney, Blg MO2, University of Sydney, Sydney, NSW 2006, Australia. nathaniel.marshall@sydney.edu.au.
Abstract

RATIONALE:
Placebo responses are complex psychobiological phenomena and often involve patient expectation of benefit. With continuous positive airway pressure (CPAP) treatment of obstructive sleep apnoea, greater hours of CPAP use are associated with reduced sleepiness. However, these open-label studies have not controlled for patient expectation of benefit derived from their knowledge of hours of device use.

OBJECTIVES:
To investigate the relative effectiveness of the use of real or placebo CPAP on daytime sleepiness.

METHODS:
Patient-level meta-analysis combining data on sleepiness measured by the Epworth Sleepiness Scale from three randomised placebo-controlled crossover trials. Mixed model analysis of variance was used to quantify the effects of real versus placebo device treatment, usage, their interaction and regression to the mean.

MEASUREMENTS AND MAIN RESULTS:
Duration of real and placebo CPAP use was correlated within patients (r=0.53, p<0.001). High use of real CPAP reduced sleepiness more than high use of placebo (difference 3.0 points; 95% CI 1.7 to 4.3, p<0.001) and more than low use of real CPAP (difference 3.3; 95% CI 1.9 to 4.7, p<0.0001). High use of placebo was superior to low use of placebo (difference 1.5; 95% CI 0.1 to 2.8, p=0.03). Twenty-nine per cent of the effect of high usage of CPAP (4.2 points; 95% CI 3.3 to 5.1) was explained by the expectation of benefit effect associated with high use of placebo (1.2 points ; 95% CI 0.2 to 2.3).

CONCLUSIONS:
A clinically significant proportion of the effectiveness of high CPAP use in reducing sleepiness is probably caused by patient expectation of benefit.

[Suddenly Worn Out]

Let me guess. A group of psychologists or psychiatrists or maybe even a pharmaeutical company that makes a lot of its money from some psychiatry drug did that study? Trying to prove, "CPAP is just a placebo, the mental fatigue of OSA is just in your mind." LMAO

What a bunch of losers. I hope it happens to them someday. I wish everyone of the people in the study gets severe OSA and either faces going on CPAP for life or if they choose not to, becomes permanently disabled.

Studies like that are irresponsible. Seriously.

Eric

[chunkyfrog]

Utterly ridiculous; and criminally irresponsible!

[xenablue]

What a bunch of morons!!

Cheers,
xena

[kteague]

[quote="johnthomasmacdonald"
CONCLUSIONS:
A clinically significant proportion of the effectiveness of high CPAP use in reducing sleepiness is probably caused by patient expectation of benefit.[/quote]

Probably? PROBABLY??? How much did they get paid to come up with a PROBABLY?

For one thing, how in the world does someone reliably and comparably placebo a cpap? Besides, the diagnosis and treatment effectiveness of OSA is evidentiary based, so however one may be temporarily convinced they feel doesn't change the facts. My gut suspects either someone created a paycheck for themselves by doing the study, or it is setting the stage to introduce a marketable "probable" solution. I hate to be such a cynic, maybe someone can explain to me the value of this study.

[avi123]

According to a 2009 multicenter study in France amongst CPAPers, 12% had RES (Residual Excessive Sleepiness) during the daytime. After excluding Depression and RLS the prevalence was reduced to 6%. Several had RES from brain hypoxic lesions caused by the CPAPs.

[BlackSpinner]

Unless they trialed it for more then a night they can't really say. I can only assume that the placebo cpap was one set to 4cm(which would be bloody uncomfortable). I would want to see the results of more then a months trial.

Personally I stopped wanting to kill anyone that got in my way within a week. People around me commented on my new sunny disposition. I also saw the ends of the tv shows I was watching with in one week.

[snuginarug]

According to a 2009 multicenter study in France amongst CPAPers, 12% had RES (Residual Excessive Sleepiness) during the daytime. After excluding Depression and RLS the prevalence was reduced to 6%. Several had RES from brain hypoxic lesions caused by the CPAPs.

I feel a bit stupid. Could you explain that in English?

[Suddenly Worn Out]

I hope OSA happens to the people who funded and ran this "study."

Eric

[Julie]

Think about this - there are a fair number of people here (a lot being newbies, but not all by any means) who, according to their software stats are actually being well treated, but still don't feel they are... and certainly disprove the placebo effect. Their problems are varied, due to many reasons, some having nothing to do with OSA or cpap, but while there might be an element of the 'effect' on some of us, especially when starting out, I don't think we'd all still be hanging in if we weren't getting real rewards (even tho' going broke in the process!).

[sylvie]

According to a 2009 multicenter study in France amongst CPAPers, 12% had RES (Residual Excessive Sleepiness) during the daytime. After excluding Depression and RLS the prevalence was reduced to 6%. Several had RES from brain hypoxic lesions caused by the CPAPs.

I feel a bit stupid. Could you explain that in English?

Yes, what does this mean? "Several had RES from brain hypoxic lesions caused by the CPAPs" -- This is disturbing if true.

[Goofproof]

Can't find enough Quack medical professionals, in this country, behave to look for morons from others. Well, you have a winner, another mindless study.

My 2 cents, who cares, if you feel better, it's working. Jim

[pats]

I have taken a quick look at the full article.

The placebo was a machine identical to a CPAP, with normal noise, airflow, and humidity, but delivering less than 0.1 cm H2O pressure.

The main conclusion in the article is confirmation that high use of CPAP for patients with OSA provides greater sleepiness reduction benefits than high use of a placebo device. Interventions that improve CPAP use from low levels (i.e., less than 4 h/night) are likely to result in real benefits for patients.

They also note that reducing pressure is unlikely to improve compliance.

The funding for the study came from The Health Research Council of New Zealand, The National Health and Medical Research Council of Australia, and British Heart Foundation.

The study seems to me to support the general approach of this forum in encouraging OSA patients to use CPAP all night, and reassuring them that there are benefits down the line. The only thing about the study that does not make sense to me is the emphasis in the final sentence of the abstract on the placebo effect, rather than on the conclusion of real effect. It may be that to researchers in this area the real effects are so obvious that the existence of even a partial placebo effect in one aspect of CPAP benefit is an interesting result. It does mean that CPAP studies should be placebo-controlled to quantify real benefit.

I do not understand some of the reactions here to the abstract. Controlled studies of the effectiveness of a medical treatment are very, very much in the best interests of all patients who use, or might use, the treatment. CPAP is a medical treatment, and should be studied and evaluated as such, not a religion that it is heresy to question.

[pats]

Probably? PROBABLY??? How much did they get paid to come up with a PROBABLY?.

"probably" is the strongest positive result you can ever get from a medical experiment. You could see a major benefit from a treatment in every one of a million patients, and there would still be a tiny, but non-zero, probability that the result is due to chance. That is why experimental results have to be subjected to statistical analysis, and the best they can do is state a result with a specified confidence.

[MidnightOwl]

I have taken a quick look at the full article.

The placebo was a machine identical to a CPAP, with normal noise, airflow, and humidity, but delivering less than 0.1 cm H2O pressure.

I didn't know they could do that. I'm curious about how they did it but not curious enough to pay for the article.

I do not understand some of the reactions here to the abstract. Controlled studies of the effectiveness of a medical treatment are very, very much in the best interests of all patients who use, or might use, the treatment. CPAP is a medical treatment, and should be studied and evaluated as such, not a religion that it is heresy to question.

Amen!