Here we go again.
Seemingly unbeknownst to acupuncture researchers around the world, the question of efficacy beyond that of placebo of inserting small needles millimeters into a patient’s skin has been answered by a number of large, well-designed, randomized and appropriately blinded clinical studies. Acupuncture has simply not been shown to be effective for any condition. The trail leading up to these trials is littered with anecdotal evidence, poorly conceived methodologies and weak treatment effects, not to mention a complete lack of a plausible mechanism of action for a near totality of the claims of benefit. But a disheartening number of people, including medical professionals at prestigious academic centers, have been duped.
This is, unfortunately, what we have come to expect with an inert therapy surrounded by a number of placebo inducing trappings such as undeserved positive press coverage, meritless state licensure, true-believing practitioners confidently spouting mystical or pseudoscientific jargon, and the laying on of hands in a relaxing environment. Just look at the practice of chiropractic, which is equally unscientific and unproven outside of acute lower back pain, for which it has been shown to be as good as but not better than conventional therapy (or doing nothing!). You can’t go 5 blocks in any direction without seeing a sign for one of these offices, usually containing a silly slogan like “Chiropractic Keeps My Spine Off My Nerves!” or “Got Chiropractic?”. But back to acupuncture.
The reality of acupuncture research is a frustrating one for medically oriented skeptics such as myself. We have difficulty seeing the world through the eyes of a true-believer in a treatment modality, because belief based on anecdotes and ideology, rather than acceptance based on plausibility and evidence, is so foreign to the way we think. If the evidence doesn’t support the practice, why does it continue? And why do researchers, like Dr. Florian Pfab, of the Technical University of Munich, continue to churn out studies like the one recently reported on in Reuters Health involving the use of acupuncture for atopic dermatitis? The answer to the first question is simple: reason is insufficient to change a thought pattern not brought about by reason in the first place. In regards to the second, I fear that these researchers know on some level that the only means of producing positive scientific support for their already firmly held belief is to ignore the foundations of science-based medicine.
The study being credulously reported on by Amy Norton of Reuters Health, most likely inspired by a press release sent by the parties involved, seems to have been published twice. It appeared in a supplement to the November 2008 European Journal of Integrative Medicine and was again accepted for publication in the European Journal of Allergy and Clinical Immunology (Allergy) in late 2009. In both abstracts, the background is essentially identical. One calls itch “a complex and unpleasant sensory experience that induces the urge to scratch”, and the other refers to it as simply “a major symptom of allergic skin disease.” Both abstracts make the unfounded claim that acupuncture has been shown to have an “effect” (the earlier version called this effect positive) on histamine-induced itch in healthy volunteers. What has been shown is that itch, like pain, nausea and pretty much any symptom with a predominantly subjective component, responds to placebo and/or distraction.
Both abstracts describe the investigation of acupuncture on allergen-induced itch and wheal/flare response in a double-blind, randomized, placebo-controlled, crossover trial. It is quite unclear from the abstracts, which is all I have access to unfortunately, whether this actually occurred. Both studies involved exposing 30 subjects with eczema to an allergen stimulus, in this case a skin prick containing house dust mite or grass pollen, both before and after receiving one of two experimental treatments, or nothing. The two experimental treatments involved so-called true or verum acupuncture, where needles were placed in specific points linked by traditional chinese medicine to improving this sort of problem, and sham acupuncture, where needles were placed in points not associated with benefit in cases of allergic skin reactions. The “no acupuncture” group was provided complementary issues of the European Journal of Integrative Medicine or something equally unlikely to improve a subjects health. Okay, I made that part up.
The severity of the itch in all three groups was recorded on visual analog scales in both studies. The difference between the publications becomes apparent in the next step. In the earlier version, after 10 minutes the size of any wheal/flare reaction was measured in addition to skin temperature, and an itch questionnaire was completed by the patient. In the more recent publication, wheal/flare size was also recorded but now skin perfusion as measured by LASER-Doppler, and not skin temperature, was included. The questionnaire results were also included.
Both abstracts report that mean itch intensity was decreased in the true acupuncture group compared to the sham and no acupuncture groups, and that sham acupuncture was better than none. The results, reported as significantly lower still fall close enough for there to be a distinct possibility that, based on the simple fact that were only around ten participants in each arm of the trial, there was in reality no difference at all between the groups. But taken at face value, the more rational interpretation is that there are varying degrees of placebo effects. We don’t know based on the abstract whether or not the person performing the acupuncture was blinded or if the blinding of subjects was sufficient. Based on the track record of this type of research, and on the design of another study by the lead author, I have my doubts. All it would take to lead to this kind of result would be for those receiving sham acupuncture to know it based upon practitioner cues. This issue could be resolved by asking participants which arm they thought they were in upon completion of the trial.
Both true and sham acupuncture were found to “significantly” decrease subsequent itch when given prior to allergen exposure compared to not receiving acupuncture. This isn’t suprising as placebo is already well established as effective in ameliorating the subjective experience of itching. It is also well established that placebo can effect the appearance of an allergic response. So it is also not suprising that wheal and flare size was smaller in the true and sham acupuncture group compared to doing nothing. But, once again, with such small study numbers, these results are essentially meaningless. Much larger and better designed studies, with innovative methods of obtaining reliable acupuncture placebo, have already been performed which look at a variety of outcomes. They show that not only does it not matter where you put the needles, it doesn’t matter if you even insert the needles. I am still left wondering what is the point of all this.
The earlier version of the study found no difference in skin temperature between groups after exposure to allergen. Suspiciously in the second version of what is the same study otherwise, skin perfusion rather than temperature was measured. The authors report that skin perfusion, which is being used as a marker for allergic response, was significantly decreased in the true acupuncture group compared to no acupuncture. Skin perfusion for the sham acupuncture isn’t included in the abstract. This difference between the two, otherwise identical, studies is problematic. Why would the authors not include the negative skin temp results in the second version and insert the claimed positive skin perfusion results. Is this simply a means of squeezing multiple publications out of one study, which is commonly done and quite shady in my opinion, or is it that the authors omitted negative results because of pro-acupuncture bias. What other outcome measures were obtained? Were they negative as well?
The conclusion of the authors is naturally positive, and also completely irrelevant. Conclusions are irrelevant in all studies. Many times they don’t jibe with the results. For instance, one recent acupuncture study showed that true acupuncture was no better than placebo. The authors claimed that both worked! They followed with the standard study boilerplate call for further investigation into why placebo acupuncture is effective. As I mentioned at the onset of this post, the questions being asked by acupuncture research have been answered. Most of them, as in the study on eczema, didn’t warrant being asked. Small studies with questionable or absent blinding are almost always wrong, especially if the treatment effect is small and the mechanism of action is implausible.
The Reuters Health article, also based on the early view online release of the paper in Allergy which I based this post on, and email correspondence with lead author Florian Pfab, is typical of mainstream coverage of alternative medicine. It gives a two sentence explanation of what eczema is, glosses over methodology, quotes the author, refers to acupuncture as ancient but throws out a possible but unproven “modern explanation”, and ends with the ubiquitous call for more research. A simple phone call to one of many well-known skeptical resources on acupuncture, or a quick google search for that matter, was all that would have been necessary to avoid such a worthless piece of pseudojournalism.
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