Mar 29 2011
Believers in acupuncture claim it is supported by plenty of published scientific evidence. Critics disagree. Thousands of acupuncture studies have been done over the last several decades, with conflicting results. Even systematic reviews have disagreed with each other. The time had come to re-visit the entire body of acupuncture research and try to make sense out of it all. The indefatigable CAM researcher Edzard Ernst stepped up to the plate. He and his colleagues in Korea and Exeter did an exhaustive study that was published in the April 2011 issue of the medical journal Pain: “Acupuncture: Does it alleviate pain and are there serious risks? A review of reviews.” It is accompanied by an editorial commentary written by yours truly: “Acupuncture’s claims punctured: Not proven effective for pain, not harmless.” (The editorial is reproduced in full below.)
Ernst et al. systematically reviewed all the systematic reviews of acupuncture published in the last 10 years: 57 systematic reviews met the criteria they set for inclusion in their analysis. They found a mix of negative, positive, and inconclusive results. There were only four conditions for which more than one systematic review reached the same conclusions, and only one of the four was positive (neck pain). They explain how inconsistencies, biases, conflicting conclusions, and recent high quality studies throw doubt on even the most positive reviews.
They also demolished the “acupuncture is harmless” myth by reporting 95 published cases of serious adverse effects including infection, pneumothorax, and 5 deaths. Some but not all of these might have been avoided by better training in anatomy and infection control.
Their analysis does not prove that acupuncture doesn’t work (negatives are hard to prove) but it unquestionably sheds serious doubt on the claim that it does work. Overall the evidence is inconsistent, and the results tend to be negative among those studies judged to be of the highest quality. Where the results are positive, the reported benefits can be explained by the surrounding ritual, the beliefs and expectations of patient and practitioner, and other nonspecific effects of treatment. There is no evidence to support the vitalistic concept of qi or the prescientific mythology of acupuncture points and meridians; it doesn’t seem to matter where you put the needles or whether the skin is pierced. More modern science-based explanations like increased endorphin production are not convincing, since placebo pills can produce the same effects.
I was delighted when the editor of Pain asked me to write a commentary to accompany the article. It gave me a soapbox in a major medical journal to say all the things I thought needed to be said about acupuncture.
My commentary was edited, but it was a very different experience from the kind of editing I experienced with O,The Oprah Magazine. It was a pleasant collaborative process aimed only at improving the clarity of the writing and strengthening the impact of what I wanted to say.
The journal thought our articles were important enough to warrant a press release. Both Ernst’s article and my commentary immediately got some attention in the media: Science Daily, Medical News Today, e! Science News, and the American Council on Science and Health all reported on them.
Believers in acupuncture will not be pleased. I expect a hostile response and am wondering if Ernst and I should invest in needle-proof vests.
Here is the entire text of my commentary. Thank you to the publishers of Pain, the IASP and Elsevier, for their permission to reproduce it here.
Acupuncture’s claims punctured: Not proven
effective for pain, not harmless
Commentary from Hall H. Acupuncture’s claims punctured: Not proven effective for pain, not harmless. PAIN 2011 Apr; 152(4): 711-712
© 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved. This article has been reproduced on ScienceBasedMedicine.org with permission of the International Association for the Study of Pain® (IASP®). The commentary may not be reproduced for any other purpose without permission. Permission to alter the article is not permitted. Permission to translate the article is not granted.
In this issue of Pain Ernst et al. , systematically reviewed a decade’s worth of systematic reviews of acupuncture. They found a mix of negative, positive, and inconclusive results. There were only four conditions for which more than one systematic review reached the same conclusions, and only one of the four was positive (neck pain). They explain how inconsistencies, biases, conflicting conclusions, and recent high quality studies throw doubt on even the most positive reviews. Ernst et al.’s analysis cannot prove that acupuncture does not work (negatives are hard to prove) but their study unquestionably sheds serious doubt on the claim that it does work. Overall the evidence is inconsistent, and among those studies judged to be of the highest quality, the results tend to be negative.
Acupuncture is based on pre-scientific concepts of a vitalistic entity (qi) and of meridians and acupuncture points unknown to anatomists. More scientific explanations have been offered as to how it might work, including a counterirritant effect or the gate control theory of pain. There is evidence that acupuncture can stimulate endogenous endorphin production, but there is evidence that placebo pills can do that as well. Importantly, when a treatment is truly effective, studies tend to produce more convincing results as time passes and the weight of evidence accumulates. When a treatment is extensively studied for decades and the evidence continues to be inconsistent, it becomes more and more likely that the treatment is not truly effective. This appears to be the case for acupuncture. In fact, taken as a whole, the published (and scientifically rigorous) evidence leads to the conclusion that acupuncture is no more effective than placebo.
Acupuncture research is inherently riddled with pitfalls. What constitutes an adequate control? People can usually tell whether or not you are sticking needles in them. Various controls have been devised, such as comparing ‘‘true’’ acupuncture points to ‘‘false’’ ones. The best control so far is an ingenious retractable needle similar to a stage dagger, where the needle just touches the skin and retracts into a sheath. Unfortunately, there is no way to blind the practitioner, so double blind studies are impossible.
The practice of acupuncture is also not sufficiently standardized, which makes it difficult, if not impossible to pin down reliably for objective study: there are various schools of acupuncture with different acupoints, and studies of acupuncture have included ‘‘electroacupuncture’’ (with or without needles), ear acupuncture, cupping, moxibustion, and other loosely related procedures. In their book, The Biology of Acupuncture, Ulett and Han  showed that transcutaneous electrical stimulation at a single arbitrary point on the wrist was just as effective as piercing the skin at traditional acupuncture points.
In more than one recent study, researchers have chosen not to use a sham acupuncture control group. Their reasoning? Since sham acupuncture has been shown to work as well as real acupuncture, then sham acupuncture must be an effective treatment too! Imagine applying this reasoning to a drug trial: if the drug and placebo got the same results, would you decide that the drug worked and that the placebo was just as therapeutic as the drug?
It does not make any difference where you put the needles or whether you use needles at all. Touching the skin with toothpicks works just as well. The crucial factor seems to be whether patients believe they are getting true acupuncture. It is becoming increasingly clear that the surrounding ritual, the beliefs of patient and practitioner, and the nonspecific effects of treatment are likely responsible for any reported benefits.
Is there really any need for more studies? Ernst et al. point out that the positive studies conclude that acupuncture relieves pain in some conditions but not in other very similar conditions. What would you think if a new pain pill was shown to relieve musculoskeletal pain in the arms but not in the legs? The most parsimonious explanation is that the positive studies are false positives. In his seminal article on why most published research findings are false, Ioannidis points out that when a popular but ineffective treatment is studied, false positive results are common for multiple reasons, including bias and low prior probability . More studies are not the answer. No matter how many studies showed negative results, they would not persuade true believers to give up their beliefs. There will always be ‘‘one more study’’ to try, but there should be a common-sense point at which researchers can agree to stop and divert research time and funds to areas more likely to produce useful results.
Of course, advocates of acupuncture have argued that it is worthwhile even if it only produces a placebo response; and that it is harmless, so it does not hurt to try it. Ernst et al. however, have shown that acupuncture is not harmless. While many of the reported adverse effects could be avoided by proper training in sterile precautions and anatomy, they correctly point out that even one avoidable adverse event is too many. With any treatment, we have to consider the risk/benefit ratio. If there is no benefit, any risk is too much. And there are other harms that they did not mention: time and money wasted, effective treatment delayed, unscientific thinking encouraged.
Placebos are unethical: our patients trust us not to prescribe them. With the current state of the evidence, I do not think we should be recommending acupuncture to our patients. On the other hand, if patients ask about it and want to try it, we should not try to stop them. We have a responsibility to educate them, but not to make decisions for them. We can tell them that although some patients believe it has helped them, the evidence does not show that it works any better than placebo, and there is a small risk of infection and other complications. With this information, they can then make their own informed decision.
In summary, Ernst et al. have shown that the evidence for efficacy of acupuncture for the treatment of pain is questionable, to say the least, and of particular concern is that its use can be dangerous. If the 57 systematic reviews they surveyed had been for a prescription drug and a similar list of serious adverse effects had been reported for that drug, we would hesitate to prescribe that drug. Is there any reason not to hold acupuncture to the same standards?
Conflict of interest statement
I have no conflicts of interest to report.
- Ernst E, Lee MS, Choi TY. Acupuncture: Does it alleviate pain and are there serious risks? A review of reviews. Pain 2011;152:755–64.
- Ioannidis JP. Why most published research findings are false: author’s reply to Goodman and Greenland. PLoS Med 2007;4:e215.
- Ulett GA, Han SP. The biology of acupuncture. St. Louis, USA: Warren H. Green Inc.; 2002. 160p.
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