May 12 2009

More on Acupuncture

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Comments: 35

I am covering the in-patient service this month and so I am more busy than usual. I am trying to keep my blogging schedule without change, but it’s challenging, so forgive me if I occasionally miss a post or I am late.

For that reason, for my post today I am simply going to respond to a comment on my recent post on acupuncture and migraines. In response to this, frequent commenter, Sonic, wrote:

The conclusion that acupuncture does not work does not coincide with the evidence presented.

From the 2009 Cocrane review:

“Four trials compared acupuncture to proven prophylactic drug treatment. Overall in these trials acupuncture was associated with slightly better outcomes and fewer adverse effects than prophylactic drug treatment.”

This implies that acupuncture is a safe and effective treatment compared to the “proven” prophylactic drug treatment.

A drug company could go to the FDA with a study that showed their treatment to be better than the existing proven treatment and get approval based on that fact.

The conclusion that it is possible that the exact placement of the needles may not be as important as thought, does not invalidate the therapy.

Just because there might be a mistake in exactly how something works does not invalidate that it does work. The studies quoted would indicate that acupuncture works as well as or better than any other current therapy.

There is nothing in the evidence to indicate that the therapy did not work better than any existing therapy and better than doing nothing.

The fact that something works better than the proven therapy means that it works.

To conclude otherwise is to misread the evidence as presented.

Sonic has missed the central point of my position on this –  the trials comparing acupuncture to standard therapy or no therapy are not blinded, therefore we cannot draw any reliable conclusion from them. Placebo effects are well established, and they include the bias of the researcher as well as the desires of the subject. By Sonic’s criteria, placebos can be said to “work”.

The real question is – does placing acupuncture needles in the skin have any desirable physiological effect, and if so does it matter where we stick them? These are the two variables of interest as they form the basis of the very concept of acupuncture.

It is my contention, based upon the evidence and what we know from basic science, that there is no clinically relevant or significant effect from sticking needles in the skin. There is plausibility to the notion that needles may induce a physiological effect, such as counter-irritation, that could reduce the activity in various pain pathways in the nervous system. But this has not been adequately demonstrated. This also lends no plausibility to any medical claims for acupuncture, but we can stick to pain indications for now.

Whether or not sticking needles into patients had any significant biological effect, we would expect placebo effects from doing so – non-specific therapeutic effects and the artifact of bias and observation. So the fact that uncontrolled trials of acupuncture show these placebo effects tells us absolutely nothing.

Sonic brought up the point that in some studies acupuncture was compared to standard therapy. There are many problems with some of these studies as often the “standard” therapy given is not adequate and therefore is a poor control. But even if adequate standard therapy is given, the comparison is unblinded (patients know if they are getting acupuncture or not) and so the results are amenable to bias and not to be trusted. (As a side note, not all studies show a benefit over standard therapy, including some of the best studies, so even this dubious conclusion is not well established.)

And no, you could not get FDA approval for a drug only with unblinded data, especially for a subjective outcome like pain.

When we look at the evidence as it applies to the two real questions at hand – does it matter if and where we stick the needles – the evidence speaks quite clearly. There is no demonstrated difference between “true” and “sham” acupuncture – meaning sticking the needles where they are supposed to be stuck according to TCM principles, vs sticking them somewhere else.

It is completely absurd from a scientific point of view to conclude from such studies that sham acupuncture “works”. Such studies are absolutely not designed to form such conclusions. You can only conclude that there is no difference between true and sham acupuncture – and therefore there is no physiological effect dependent upon the location of the needles.

This, of course, completely contradicts any TCM principles of acupuncture points, meridians, and chi.

Further, these studies represent more reliable evidence than unblinded studies – and one of the principles of evidence- based medicine is that better data trumps weaker data. So the best data shows no difference between treatment and control – which in the real world of scientific medicine (as opposed to the altnerative world of CAM) this equals no effect.

More recent acupuncture studies (although not yet with migraine that I have seen) compare placebo-acupuncture to true acupuncture. In placebo acupuncture special needles are used that do not penetrate the skin, and neither the acupuncturist nor the patient can tell the difference. In such studies there has been no difference between placebo acupuncture and true acupuncture.

So what the evidence tells us so far is that is does not matter if or where you stick acupuncture needles. These are the two variables specific to acupuncture. Therefore, acupuncture does not work. The ritual surrounding the use of acupuncture likely has some non-specific effects, and there are the usual biases and artifacts that constitute placebo effects. But acupuncture itself appears to be worthless.

There is no other rational interpretation of existing evidence, despite all the misdirections of proponents who are trying to turn scientific logic on its head.

In fact – here is yet another placebo-acupuncture study – a large study, just published, comparing true acupuncture, sham acupuncture, and “fake” or placebo acupuncture (using tooth picks that do not penetrate the skin) in chronic back pain. The results – no difference between the groups.

Scientific conclusion – it does not matter where or even if you stick the needles, i.e. acupuncture does not work.

Conclusion of proponents:

The leader of the trial, Dr Daniel Cherkin, from the Group Health Centre for Health Studies in Seattle, said: “We found that simulated acupuncture, without penetrating the skin, produced as much benefit as needle acupuncture – and that raises some new questions about how acupuncture works.”

Wrong – these results raise the question of if acupuncture works, not how it works.  His colleague, Dr. Karen Sherman, is much closer to the truth:

“Maybe the context in which people get the treatment has effects that are more important than the mechanically induced effects.”

Right – the context, meaning the placebo effects. And “more important” meaning that there are only placebo effects and no “mechanically induced effects.”

In other works – it doesn’t work. Give it up. Move on.

35 responses so far