MD, PhD, FMedSci, FSB, FRCP, FRCPEd

bias

Still in the spirit of ACUPUNCTURE AWARENESS WEEK, I have another critical look at a recent paper. If you trust some of the conclusions of this new article, you might think that acupuncture is an evidence-based treatment for coronary heart disease. I think this would be a recipe for disaster.

This condition affects millions and eventually kills a frighteningly large percentage of the population. Essentially, it is caused by the fact that, as we get older, the blood vessels supplying the heart also change, become narrower and get partially or even totally blocked. This causes lack of oxygen in the heart which causes pain known as angina pectoris. Angina is a most important warning sign indicating that a full blown heart attack might be not far.

The treatment of coronary heart disease consists in trying to let more blood flow through the narrowed coronaries, either by drugs or by surgery. At the same time, one attempts to reduce the oxygen demand of the heart, if possible. Normalisation of risk factors like hypertension and hypercholesterolaemia are key preventative strategies. It is not immediate clear to me how acupuncture might help in all this – but I have been wrong before!

The new meta-analysis included 16 individual randomised clinical trials. All had a high or moderate risk of bias. Acupuncture combined with conventional drugs (AC+CD) turned out to be superior to conventional drugs alone in reducing the incidence of acute myocardial infarction (AMI). AC+CD was superior to conventional drugs in reducing angina symptoms as well as in improving electrocardiography (ECG). Acupuncture by itself was also superior to conventional drugs for angina symptoms and ECG improvement. AC+CD was superior to conventional drugs in shortening the time to onset of angina relief. However, the time to onset was significantly longer for acupuncture treatment than for conventional treatment alone.

From these results, the authors [who are from the Chengdu University of Traditional Chinese Medicine in Sichuan, China] conclude that “AC+CD reduced the occurrence of AMI, and both acupuncture and AC+CD relieved angina symptoms and improved ECG. However, compared with conventional treatment, acupuncture showed a longer delay before its onset of action. This indicates that acupuncture is not suitable for emergency treatment of heart attack. Owing to the poor quality of the current evidence, the findings of this systematic review need to be verified by more RCTs to enhance statistical power.”

As in the meta-analysis discussed in my previous post, the studies are mostly Chinese, flawed, and not obtainable for an independent assessment. As in the previous article, I fail to see a plausible mechanism by which acupuncture might bring about the effects. This is not just a trivial or coincidental observation – I could cite dozens of systematic reviews for which the same criticism applies.

What is different, however, from the last post on gout is simple and important: if you treat gout with a therapy that is ineffective, you have more pain and eventually might opt for an effective one. If you treat coronary heart disease with a therapy that does not work, you might not have time to change, you might be dead.

Therefore I strongly disagree with the authors of this meta-analysis; “the findings of this systematic review need NOT to be verified by more RCTs to enhance statistical power” — foremost, I think, the findings need to be interpreted with much more caution and re-written. In fact, the findings show quite clearly that there is no good evidence to use acupuncture for coronary heart disease. To pretend otherwise is, in my view, not responsible.

There might be an important lesson here: A SEEMINGLY SLIGHT CORRECTION OF CONCLUSIONS OF SUCH SYSTEMATIC REVIEWS MIGHT SAVE LIVES.

This week is acupuncture awareness week, and I will use this occasion to continue focusing on this therapy. This first time ever event is supported by the British Acupuncture Council who state that it aims to “help better inform people about the ancient practice of traditional acupuncture. With 2.3 million acupuncture treatments carried out each year, acupuncture is one of the most popular complementary therapies practised in the UK today.

Right, let’s inform people about acupuncture then! Let’s show them that there is often more to acupuncture research than meets the eye.

My team and I have done lots of research into acupuncture and probably published more papers on this than any other subject. We had prominent acupuncturists on board from the UK, Korea, China and Japan, we ran conferences, published books and are proud to have been innovative and productive in our multidisciplinary research. But here I do not intend to dwell on our own achievements, rather I will highlight several important new papers in this area.

Korean authors just published a meta-analysis to assess the effectiveness of acupuncture as  therapy for gouty arthritis. Ten RCTs involving 852 gouty arthritis patients were included. Six studies of 512 patients reported a significant decrease in uric acid in the treatment group compared with a control group, while two studies of 120 patients reported no such effect. The remaining four studies of 380 patients reported a significant decrease in pain in the treatment group.

The authors conclude “that acupuncture is efficacious as complementary therapy for gouty arthritis patients”.

We should be delighted with such a positive and neat result! Why then do I hesitate and have doubts?

I believe that this paper reveals several important issues in relation to systematic reviews of Chinese acupuncture trials and studies of other TCM interventions. In fact, this is my main reason for discussing the new meta-analysis here. The following three points are crucial, in my view:

1) All the primary studies were from China, and 8 of the 10 were only available in Chinese.

2) All of them had major methodological flaws.

3) It has been shown repeatedly that all acupuncture-trials from China are positive.

Given this situation, the conclusions of any review for which there are only Chinese acupuncture studies might as well be written before the actual research has started. If the authors are pro-acupuncture, as the ones of the present article clearly are, they will conclude that “acupuncture is efficacious“. If the research team has some critical thinkers on board, the same evidence will lead to an entirely different conclusion, such as “due to the lack of rigorous trials, the evidence is less than compelling.

Systematic reviews are supposed to be the best type of evidence we currently have; they are supposed to guide therapeutic decisions. I find it unacceptable that one and the same set of data could be systematically analysed to generate such dramatically different outcomes. This is confusing and counter-productive!

So what is there to do? How can we prevent being misled by such articles? I think that medical journals should refuse to publish systematic reviews which so clearly lack sufficient critical input. I also believe that reviewers of predominantly Chinese studies should provide English translations of these texts so that they can be independently assessed by those who are not able to read Chinese – and for the sake of transparency, journal editors should insist on this point.

And what about the value of acupuncture for gouty arthritis? I think I let the readers draw their own conclusion.

“They would say that, wouldn’t they?”  is the quote attributed to Mandy Rice-Davies giving witness in the Profumo affair. I think, it aptly highlights some of the issues related to conflicts of interest in health care.

These days, when a researcher publishes a paper, he will in all likelihood have to disclose all conflicts of interest he might have. The aim of this exercise is to be as transparent as possible; if someone has received support from a commercial company, for example, this fact does not necessarily follow that his paper is biased, but it is important to lay open the fact so that the readers can make up their own minds.

The questionnaires that authors have to complete prior to publication of their article focus almost exclusively on financial issues. For instance, one has to disclose any sponsorship, fees, travel support or shares that one might own in a company. In conventional medicine, these matters are deemed to be the most important sources for potential conflicts of interest.

In alternative medicine, financial issues are generally thought to be far less critical; it is generally seen as an area where there is so little money that it is hardly worth bothering. Perhaps this is the reason why few journals in this field insist on declarations of conflicts of interests and few authors disclose them.

After having been a full-time researcher of alternative medicine for two decades, I have become convinced that conflicts of interest are at least as prevalent and powerful in this field as in any other area of health care. Sure, there is less money at stake, but this fact is more than compensated by non-financial issues. Quasi-evangelic convictions abound in alternative medicine and it is, I think, obvious that they can amount to significant conflicts of interest.

During their training, alternative practitioners are being taught many things which are unproven, have no basis in fact or are just plainly wrong. Eventually this schooling can create a belief system which often is adhered to regardless of the scientific evidence and which tends to be defended at all cost. As some of my readers are bound to object to this remark, I better cite an example: during their training, students of chiropractic develop a more and more firm stance against immunization which in all likelihood is due to the type of information they receive at the chiropractic college. There is no question in my mind that creeds can represent an even more powerful conflict of interest than financial matters.

Moreover, this belief is indivisibly intertwined with existential issues. In alternative medicine, there may not be huge amounts of money at stake but practitioners’ livelihoods are perceived to be at risk. If an acupuncturist, for instance, argues in favour of his therapy, he also consciously or sub-consciously is trying to protect his income.

Some might say that this not different from conventional medicine, but I disagree: if we take away one specific therapy from a doctor because it turns out to be useless or unsafe, he will be able to use another one; if we take the acupuncture needle away from an acupuncturist, we have deprived him of his livelihood.

This is why conflicts of interest in alternative medicine tend to be very acute, powerful and personal. And this is why enthusiasts of alternative medicine are incapable or unwilling to look upon any type of critical assessment of their area as anything else than an attack on their income, their beliefs, their status, their training or their person. If anyone should doubt it, I recommend studying the comments I received to previous posts of this blog.

When Mandi Rice-Davies gave evidence during the trial of Stephen Ward, the osteopath who had introduced her to influential clients, the prosecuting council noted that Lord Astor denied having had an affair with her. Mrs Rice-Davies allegedly replied “Well, he would say that, wouldn’t he?” (Actually, she did not say these exact words but something rather similar) When I read the comments following my posts on this blog, I am often reminded of this now classical quote.

When chiropractors deny that neck manipulations carry a risk, when herbalists insist that traditional herbalism is based on good evidence, when homeopaths claim that their remedies are more than placebos, I believe we should ask who, in these debates, might have a conflict of interest.

Is there a circumstance of one party in the discussion where personal interests might benefit from the argument? Who is more likely to be objective, the person whose livelihood is endangered or the independent expert who studied the subject in depth but has no axe to grind? If you ask these questions, you might conclude as I frequently do: “they would say that, wouldn’t they?”

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