What does it mean when “true” acupuncture works no better than a sham procedure, but both interventions improve patients’ symptoms?

Pick your answer below:

a. Both interventions work as placebos only

b. Both interventions are more than just placebos

c. I can’t answer definitively

This morning I came across Reuters’ coverage of yet another acupuncture study with peculiar results: http://www.reuters.com/article/2011/08/31/us-acupuncture-nobetter-idUSTRE77U63L20110831

The goal of this study was to establish whether acupuncture can be helpful in the treatment of the Polysystic Ovary Syndrome –- a hormone disorder characterized by irregular periods, acne, and insulin resistance, often associated with obesity — and to find out how it fares against the sham procedure. Women in both the true and the sham groups saw an improvement in hormones related to pregnancy and ovulation, and tended to have more periods after the study sessions than before. There was only a small difference between the two groups. ”Whether there’s actually some physiological benefit from a sham acupuncture treatment, I don’t know,” said study author Lisa Pastore, from the University of Virginia in Charlottesville. “It could be that the hope of getting better with acupuncture makes a difference”, — she told Reuters Health, “or that the benefit of simply slowing down, lying down in a quiet room” during either treatment was behind hormone and ovulation changes”.

It seems that Dr. Pastore went for c.

Most skeptics would jump on a.

But let’s give it further consideration before jumping to the conclusion. There is more to the question than meets the eye. The devil is in the details.

One thing that can be said with a good degree of certainty is that acupuncture is a complex intervention with many potential mechanisms of action. Sure, the placebo effect plays a huge role, as it does in many medical interventions. In fact, it might be even stronger in acupuncture due to its elaborate “ritualistic” component, Ted Kapchuk of Harvard Medical School argues.  http://www.annals.org/content/136/11/817

Even modern drugs that are vetted through rigorous double blind studies are not immune from doubts about their effectiveness due to placebo effect. Circa 2008, PLoS Medicine published a meta-analysis study on the SSRI’s drugs that are routinely used to treat depression. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2582668/ Here is an excerpt by Prof. Irving Kirsch that conducted the study: “The results of our meta-analysis showed that people got better on medication, but they also got better on placebo, and the difference between the two was small. In fact, it was below the criterion for clinical significance established by the National Institute for Health and Clinical Excellence (NICE), which sets treatment guidelines for the National Health Service in the UK”.

Intriguingly, acupuncture seems to create both the placebo mediated effect on the brain and the more specific effect, according to a recent study that employed the fMRI technology: “Although controversy regarding appropriate control methodology (e.g. sham acupuncture) continues, data suggest that modulation of certain limbic brain networks may differentiate between specific and placebo components of acupuncture.”- Pain magazine, 2007. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1913212

Last but not least: not all “sham” procedures are created equal. Way too often in acupuncture research, the so called “control” is not inert, and may have a therapeutic effect (beyond placebo) of its own. In Dr. Pastore’s research, fake needles were used to create an illusion of acupuncture without penetrating the skin. But these devices do stimulate mechanoreceptors, which are the sensory receptors that respond to mechanical pressure. So, was control good enough? Maybe… Maybe not… And here is another curve ball:  what we call “true” acupuncture in acupuncture research is often a sub-optimal version of acupuncture. In clinical practice there is more fine-tuning in the selection of the needling sites to account for the clinical diversity. So, if our labeling of “True” and “Sham” for the two treatment groups in the research does not adequately reflect reality, wouldn’t we get distorted data as output?

So, where do we stand? As far as the answer to the quiz, it is probably c. – insufficient data.

Here are a couple of thoughts / suggestions which may help to gain a better understanding of the subject:

  1. Most acupuncture studies explore general effect on pain and/or on the functioning of the central nervous system. Yet in real life many patients turn to acupuncture for the “local” ailments such as tendinitis, bursitis, arthritis, and various strains and sprains. These are problems that are treated with Physical Therapy as well. Based on my anecdotal experience, I would not be surprised if acupuncture – either by itself or combined with electrical stimulation through the needles (percutaneous electrical stimulation) — worked better than conventional Physical Therapy for, say, Achilles tendinitis. We need good studies evaluating “local” effects of acupuncture.
  1. In the study on electrical acupuncture for the postoperative pain, I used “active placebo” as control. Same set of points was stimulated either mechanically or electrically in two groups of post-surgical patients (patients were assigned randomly to these groups) with different short-term outcomes. http://www.painmanagementnursing.org/article/S1524-9042(09)00101-5/

Applying different types of stimulation to the same points can also be useful in teasing out the different physiological mechanisms at work.

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