Yes, we discussed this study on a previous blog post. But, as it is ‘ACUPUNCTURE AWARENESS WEEK’ in the UK, and because of another reason (which will become clear in a minute) I decided to revisit the trial.
In case you have forgotten, here is its abstract once again:
Background: Hot flashes (HFs) affect up to 75% of menopausal women and pose a considerable health and financial burden. Evidence of acupuncture efficacy as an HF treatment is conflicting.
Objective: To assess the efficacy of Chinese medicine acupuncture against sham acupuncture for menopausal HFs.
Design: Stratified, blind (participants, outcome assessors, and investigators, but not treating acupuncturists), parallel, randomized, sham-controlled trial with equal allocation. (Australia New Zealand Clinical Trials Registry: ACTRN12611000393954)
Setting: Community in Australia.
Participants: Women older than 40 years in the late menopausal transition or postmenopause with at least 7 moderate HFs daily, meeting criteria for Chinese medicine diagnosis of kidney yin deficiency.
Interventions: 10 treatments over 8 weeks of either standardized Chinese medicine needle acupuncture designed to treat kidney yin deficiency or noninsertive sham acupuncture.
Measurements: The primary outcome was HF score at the end of treatment. Secondary outcomes included quality of life, anxiety, depression, and adverse events. Participants were assessed at 4 weeks, the end of treatment, and then 3 and 6 months after the end of treatment. Intention-to-treat analysis was conducted with linear mixed-effects models.
Results: 327 women were randomly assigned to acupuncture (n = 163) or sham acupuncture (n = 164). At the end of treatment, 16% of participants in the acupuncture group and 13% in the sham group were lost to follow-up. Mean HF scores at the end of treatment were 15.36 in the acupuncture group and 15.04 in the sham group (mean difference, 0.33 [95% CI, −1.87 to 2.52]; P = 0.77). No serious adverse events were reported.
Limitation: Participants were predominantly Caucasian and did not have breast cancer or surgical menopause.
Conclusion: Chinese medicine acupuncture was not superior to noninsertive sham acupuncture for women with moderately severe menopausal HFs.
When I first discussed this trial, I commented that the trial has several strengths: it includes a large sample size and the patients were adequately blinded to eliminate the effects of expectations. It was published in a top journal, and we can therefore assume that it was properly peer-reviewed. Combined with the evidence from our previous systematic review, this indicates that acupuncture has no effect beyond placebo.
The reason for bringing it up again is that a comment about the study has recently appeared, not just any old comment but one from the British Medical Acupuncture Society. It is, in my view, gratifying and interesting. It was published on ‘facebook’ and is therefore in danger of getting forgotten. I hope to preserve it by citing it in full.
Here it is:
A large rigorous trial published in a prestigious general medical journal, and the usual mantra rings out – acupuncture is no better than sham. In this case there was not a fraction of difference from a non-penetrating sham in a two-armed trial with over 300 women. Ok,…so we have known for some time that we really need 400 in each arm to demonstrate the usual difference over sham seen in meta-analysis in pain conditions, but there really was not even a sniff of a difference here. So is that it for acupuncture in hot flushes? Well, we have a 40% symptom reduction in both groups, and a strong conviction from some practitioners that it really seems to work. Is 40% enough for a strong conviction? I have heard some dramatic stories from medical acupuncturist colleagues that really would be hard to dismiss as non-specific effects, and from others I have heard relative ambivalence about the effects in hot flushes.
Personally I always try to consider mechanisms, and I wish researchers in the field would do the same before embarking on their trials. That is not intended as a criticism of this trial, but some consideration of mechanisms might allow us to explain all our data, including the contribution of this trial.
Acupuncture has recognised effects that are local to the needle, in the spinal cord (mainly in the segments stimulated) and in the brain (as well as humoral effects in CSF and blood). The latter are probably the mildest of the three categories, and require the best group of patient responders for them to be observable in clinical practice.
Menopausal hot flushes are explained by the effects of reduced oestrogens on the thermoregulatory centre in the anterior hypothalamus. It is certainly plausible that the neuro-inhibitory effects of endogenous opioids such as beta-endorphin, which we know can be released by acupuncture stimulation in experimental settings, could stablise neurones in the anterior hypothalamus that have become irritable due to a sudden drop in oestrogens.
So are endogenous opioids always released by acupuncture? Well, they and their effects seem to be measurable in experiments that use what I call proper acupuncture. That is, strong stimulation to deep somatic tissue. In the laboratory, and indeed in my clinic, this is only usually achieved in a palatable manner by electroacupuncture to muscle, although repeated manual stimulation every few minutes may have similar effects.
Ee et al used a relatively gentle acupuncture protocol, so they may have only generated measurable effects, based on mechanistic speculation, in the most responsive patients, perhaps less than 10%.
What does all this tell us? Well this trial clearly demonstrates that gentle acupuncture protocols generate effects in women with hot flushes via context rather than penetrating needling. In conditions that rely on central effects, I think we still need to consider stronger stimulation protocols and enriched enrollment in trials, ie preselecting responders before randomisation.
In my original comment I also predicted: “One does not need to be a clairvoyant to predict that acupuncturists will now find what they perceive as a flaw in the new study and claim that its results were false-negative.”
I am so glad Mike Cummings and the BMAS rushed to prove me right.
It’s so nice to know one can rely on someone in these uncertain times!