quarta-feira, 16 de abril de 2008


Acupuncture relieves cancer chemotherapy fatigue

Chemotherapy wipes people out and any treatment that would provide a boost in energy would be welcome. If researchers were doing disinterested science, they would do a large study (at least 25 in each group), and it would be double-blinded, randomized, placebo-controlled, have a low attrition rate, and be published in a high-quality scientific journal. (See Bausell 2007: 104). The acupuncture study touted by New Scientist had 47 participants and three groups, and is described by the researchers as "a randomised placebo-controlled trial."

The patients were randomly assigned to one of three groups to receive either acupuncture or acupressure – placing physical pressure on acupuncture points with hands or objects – or sham acupressure.

The acupuncture group received six 20-minute sessions over a period of three weeks. The acupoints "were selected for their supposed propensity to boost energy levels and reduce fatigue." The acupressure group administered their own therapy. They were taught to massage the same acupoints for one minute a day for two weeks. The sham acupressure group also administered their own therapy, but were given different points to massage. One key ingredient for a placebo-controlled study seems missing: the administration of the therapy by the healer in the clinical setting for the two acupressure groups. Also, the way this study was conducted meant that compliance with the acupuncture group was known and likely to be high, whereas compliance with the acupressure groups would have to rely on self-reporting. In fact, even though this is a rather small study, one would predict—based on what we know about the placebo effect—that the difference in method of delivery of the treatment would lead to the acupuncture group reporting the best results. Another defect in the study is that the acupressure groups applied their therapy a minute a day for two weeks (28 minutes of self-treatment), while the acupuncture group received its therapy for three weeks (two 20-minute sessions per week, for a total of 120 minutes of therapy in a clinical setting). The difference in delivery of treatment by a healer in a clinical setting versus self-administration could account for any difference in effect, as could the difference in duration of the treatments.

The results were that "patients in the acupuncture group reported a 36% improvement in fatigue levels, whilst those in the acupressure group improved by 19%. Those in the sham acupressure group reported a 0.6% improvement." In other words, the results are what you would expect if acupuncture is a placebo. It worked better than acupressure because the patients had more reason to believe in the effectiveness of the therapy and more reason to expect good results.

The large difference between the two acupressure groups is interesting, however. It could be an artifact of the small size of the samples, of the dropout rate (not mentioned in the article), or of the way improvement was measured; or it could indicate that traditional trigger points of acupressure are more effective than non-trigger points. Whatever this study indicates, there is little justification for claiming that it indicates that acupuncture relieves cancer chemotherapy fatigue.

The study was published in the journal Complementary Therapies in Medicine (Volume 15, Issue 4, Pages 228-237). It's called "The management of cancer-related fatigue after chemotherapy with acupuncture and acupressure: A randomised controlled trial." It was done at Manchester’s Christie Hospital by Alexander Molassiotis et al. We await replication, but with larger samples and better controls for the placebo effect. In the meantime, I suggest that New Scientist rewrite the headline to read:

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