MD, PhD, FMedSci, FSB, FRCP, FRCPEd

risk/benefit

One of the most gratifying aspect of my work in Exeter was being able to offer posts to visiting researchers from across the world. Some of these co-workers, after returning to their home countries, became prominent scientists in their own right, and quite a few remained in contact and continued to collaborate with me or with members of my team. In one of these collaborative projects, we wanted to investigate adverse events attributed to traditional medical treatments in the Republic of Korea.

For this purpose, we reviewed adverse events recorded in the Republic of Korea, between 1999 and 2010, by the Food and Drug Administration, the Consumer Agency or the Association of Traditional Korean Medicine. Records of adverse events attributed to the use of traditional medical practices, including reports of medicinal accidents and consumers’ complaints, were evaluated.

Overall, 9624 records of adverse events were identified. Liver problems after the administration of herbal medicines were the most frequently reported adverse events. Only eight of the adverse events were recorded by the pharmacovigilance system run by the Food and Drug Administration. Of the 9624 events, 1389 – mostly infections, cases of pneumothorax and burns – were linked to physical therapies (n = 285) or acupuncture/moxibustion (n = 1104).

We concluded that traditional medical practices often appear to have adverse effects, yet almost all of the adverse events attributed to such practices between 1999 and 2010 were missed by the national pharmacovigilance system. The Consumer Agency and the Association of Traditional Korean Medicine should be included in the national pharmacovigilance system.

The assumption that alternative treatments are entirely harmless is widespread, not least because it is incessantly promoted via millions of web-site, thousands of books, newspaper articles, VIPs like Prince Charles etc. etc. Consumers are incessantly being told that NATURAL = SAFE. Yet, if we look closely, most alternative treatments are not natural and, as this investigation demonstrates, they are certainly not devoid of risks.

I already see the apologists preparing to comment that, compared to conventional therapies, alternative treatments are very safe. So let me pre-empt this fallacy by pointing out (yet again) that 1) in the absence of adequate surveillance systems, nobody can say how frequent adverse-effects of alternative treatments really are, and that 2) even severe adverse effects can normally be tolerated, if the treatment in question has been shown to be efficacious.

So, instead of commenting on my repeated reports about the risks of alternative medicine, I invite, in fact, I challenge my critics to answer this simple question: For how many alternative therapies is there a well-documented positive risk/benefit balance?

I happen to be convinced that safety issues related to alternative medicine are important – very important, in fact. Therefore I will continue to report on recent publications addressing them – even at the risk of irritating a few of my readers. And here is such a recent publication:

This review, a sequel to one published 10 years ago, is an evaluation of the number and the severity of adverse events (AEs) reported after acupuncture, moxibustion, and cupping between 2000 and 2011. Relevant English-language reports in 6 databases were identified and assessed by two reviewers; no Asian databases were searched and no articles were included which were in languages other than English. 117 reports of 308 AEs from 25 countries and regions were associated with acupuncture (294 cases), moxibustion (4 cases), or cupping (10 cases). Three patients died after receiving acupuncture.

A total of 239 of infections associated with acupuncture were reported in 17 countries and regions. Korea reported 162 cases, Canada 33, Hong Kong 7, Australia 8, Japan 5, Taiwan 5, UK 4, USA 6, Spain 1, Ireland 1, France 1, Malaysia 1, Croatia 1, Scotland 1, Venezuela 1, Brazil 1, and Thailand 1. Of 38 organ or tissue injuries, 13 were pneumothoraxes; 9 were central nerve system injuries; 4 were peripheral nerve injuries; 5 were heart injuries; 7 were other injuries. These cases originated from 10 countries: 10 from South Korea, 6 from the USA, 6 from Taiwan, 5 from Japan, 3 from the UK, 2 from Germany, 2 from Hong Kong, 1 from Austria, 1 from Iran, 1 from Singapore, and 1 from New Zealand.

The authors concluded “although serious AEs associated with acupuncture are rare, acupuncture practice is not risk-free. Adequate regulation can even further minimize any risk. We recommend that not only adequate training in biomedical knowledge, such as anatomy and microbiology, but also safe and clean practice guidelines are necessary requirements and should continue to be enforced in countries such as the United States where they exist, and that countries without such guidelines should consider developing them in order to minimize acupuncture AEs.”

When I last wrote about the risks of acupuncture, I discussed a Chinese paper reporting 1038 cases of serious adverse events, including 35 fatalities. I was keen to point out that, due to under-reporting, this might just be the tip of a much bigger iceberg. Subsequently, my inbox was full with hate-mail, and comments such as this one appeared on the blog: “This is tiresome old stuff, and we have to wonder what’s wrong with Ernst that he still peddles his dubious arguments.”

I suspect that I will see similar reactions to this post. It probably does not avert the anger to point out that the authors of the new article are, in fact, proponents of acupuncture. Neither will it cool the temper of acupuncture-fans to stress that the new paper completely ignored the Chinese literature as well as articles not published in English; this means that the 1038 Chinese cases (and an unknown amount published in other languages; after all, there might be a lot of published material in Japanese, Korean or other Asian languages) would need adding to the published 308 cases summarised in the new article; and this, in turn, means that the numbers provided here are not even nearly complete. And finally, my re-publishing the conclusions from my previous post is unlikely to apease many acupuncture-enthusiasts either:

True, these are almost certainly rare events – but we have no good idea how rare they are. There is no adverse event reporting scheme in acupuncture, and the published cases are surely only the tip of the ice-berg. True, most other medical treatments carry much greater risks! And true, we need to have the right perspective in all of this!

So let’s put this in a reasonable perspective: with most other treatments, we know how effective they are. We can thus estimate whether the risks outweigh the benefit, and if we find that they do, we should (and usually do) stop using them. I am not at all sure that we can perform similar assessments in the case of acupuncture.

Some national and international guidelines advise physicians to use spinal manipulation for patients suffering from acute (and chronic) low back pain. Many experts have been concerned about the validity of this advice. Now an up-date of the Cochrane review on this subject seems to provide clarity on this rather important matter.

Its aim was to assess the effectiveness of spinal manipulative therapy (SMT) as a treatment of acute low back pain. Randomized controlled trials (RCTs) testing manipulation/mobilization in adults with  low back pain of less than 6-weeks duration were included. The primary outcome measures were pain, functional status and perceived recovery. Secondary endpoints were return-to-work and quality of life. Two authors independently conducted the study selection, risk of bias assessment and data extraction. The effects were examined for SMT versus  inert interventions, sham SMT,  other interventions, and for SMT as an adjunct to other forms of treatment.

The researchers identified 20 RCTs with a total number of 2674 participants, 12 (60%) RCTs had not been included in the previous version of this review. Only 6 of the 20 studies had a low risk of bias. For pain and functional status, there was low- to very low-quality evidence suggesting no difference in effectiveness of SMT compared with inert interventions, sham SMT or as adjunct therapy. There was varying quality of evidence suggesting no difference in effectiveness of SMT compared with other interventions. Data were sparse for recovery, return-to-work, quality of life, and costs of care.

The authors draw the following conclusion: “SMT is no more effective for acute low back pain than inert interventions, sham SMT or as adjunct therapy. SMT also seems to be no better than other recommended therapies. Our evaluation is limited by the few numbers of studies; therefore, future research is likely to have an important impact on these estimates. Future RCTs should examine specific subgroups and include an economic evaluation.”

In other words, guidelines that recommend SMT for acute low back pain are not based on the current best evidence. But perhaps the situation is different for chronic low back pain? The current Cochrane review of 26 RCTs is equally negative: “High quality evidence suggests that there is no clinically relevant difference between SMT and other interventions for reducing pain and improving function in patients with chronic low-back pain. Determining cost-effectiveness of care has high priority. Further research is likely to have an important impact on our confidence in the estimate of effect in relation to inert interventions and sham SMT, and data related to recovery.”

This clearly begs the question why many of the current guidelines seem to mislead us. I am not sure I know the answer to this one; however I suspect that the panels writing the guidelines might have been dominated by chiropractors and osteopaths or their supporters who have not exactly made a name for themselves for being impartial. Whatever the reason, I think it is time for a re-think and for up-dating guidelines which are out of date and misleading.

Similarly, it might be time to question for what conditions chiropractors and osteopaths, the two professions who use spinal manipulation/mobilisation most, do actually offer anything of real value at all. Back pain and SMT are clearly their domains; if it turns out that SMT is not evidence-based for back pain, what is left? There is no good evidence for anything else, as far as I can see. To make matters worse, there are quite undeniable risks associated with SMT. The conclusion of such considerations is, I fear, obvious: the value of and need for these two professions should be re-assessed.

My aim with this blog is to eventually cover most of the 400 or so different alternative therapies and diagnostic techniques. So far, I have focused on some of the most popular modalities; and this means, I have neglected many others. Today, it is time, I think, to discuss aromatherapy, after all, it is one of the most popular forms of alternative medicine in the UK.

Aromatherapists use essential oils, and this is where the confusion starts. They are called “essential” not because humans cannot do without them, like essential nutrients, for instance; they are called “essential” because they are made of flower ESSENCES. The man who ‘discovered’ aromatherapy was a chemist who accidentally had burnt his hand and put some lavender essence on the burn. It healed very quickly, and he thus concluded that essential oils can be useful therapeutics.

Today’s aromatherapists would rarely use the pure essential oil; they dilute it in an inert carrier oil and usually apply it via a very gentle massage to the skin. They believe that specific oils have specific effects for specific conditions. As these oils contain pharmacologically active ingredients, some of these assumptions might even be correct. The question, however, is one of concentration. Do these ingredients reach the target organ in sufficient quantities? Are they absorbed through the skin at all? Does smelling them have a sufficiently large effect to produce the claimed benefit?

The ‘acid test’ for any therapeutic claim is, as always, the clinical trial. As it happens a new paper has just become available. The aim of this randomised study was to determine the effects of inhalation aromatherapy on pregnant women. Essential oils with high linalool and linalyl acetate content were selected and among these the one preferred by the participant was used. Thirteen pregnant women in week 28 of a single pregnancy were randomly assigned into an aromatherapy and a control group. The main outcome measures were several validated scores to assess mood and the heart-rate variability. The results showed significant differences in the Tension-Anxiety score and the Anger-Hostility score after aromatherapy. Heart rate variability changes indicated that the parasympathetic nerve activity increased significantly in the verum group. The authors concluded that aromatherapy inhalation was effective and suggest that more research is warranted.

I have several reasons for mentioning this study here.

1st research into aromatherapy is rare and therefore any new trial of this popular treatment might be important.

2nd aromatherapy is mostly (but not in this study) used in conjunction with a gentle, soothing massage; any outcome of such an intervention is difficult to interpret: we cannot then know whether it was the massage or the oil that produced the observed effect. The present trial is different and might allow conclusions specifically about the effects of the essential oils.

3rd the study displays several classic methodological mistakes which are common in trials of alternative medicine. By exposing them, I hope that they might become less frequent in future.

The most obvious flaw is its tiny sample size. What is an adequate size, people often ask. This question is unfortunately unanswerable. To determine the adequate sample size, it is best to conduct a pilot study or use published data to calculate the required number of patients needed for the specific trial you are planning. Any statistician will be able to help you with this.

The second equally obvious flaw relates to the fact that the results and the conclusions of this study were based on comparing the outcome measures before with those after the interventions within one intervention group. The main reason for taking the trouble of running a control group in a clinical trial is that the findings from the experimental group are compared to those of the control group. Only such inter-group comparisons can tell us whether the results were actually caused by the intervention and not by other factors such as the passage of time, a placebo-effect etc.

In the present study, the authors seem to be aware of their mistake and mention that there were no significant differences in outcomes when the two groups were compared. Yet they fail to draw the right conclusion from this fact. It means that their study demonstrated that aromatherapy inhalation had no effect on the outcomes studied.

So, what does the reliable trial evidence on aromatherapy tell us?

A clinical trial in which I was involved failed to show that it improves the mood or quality of life of cancer patients. But one swallow does not make a summer; what do systematic reviews of all available trials indicate?

The first systematic review was probably the one we published in 2000. We then located 12 randomised clinical trials: six of them had no independent replication; six related to the relaxing effects of aromatherapy combined with massage. These 6 studies collectively suggested that aromatherapy massage has a mild but short-lasting anxiolytic effect. These effects of aromatherapy are probably not strong enough for it to be considered for the treatment of anxiety. We concluded that the hypothesis that it is effective for any other indication is not supported by the findings of rigorous clinical trials.

Since then several other systematic reviews have emerged. We therefore decided to summarise their findings in an overview of all available reviews. We searched 12 electronic databases and our departmental files without restrictions of time or language. The methodological quality of all systematic reviews was evaluated independently by two authors. Of 201 potentially relevant publications, 10 met our inclusion criteria. Most of the systematic reviews were of poor methodological quality. The clinical subject areas were hypertension, depression, anxiety, pain relief, and dementia. For none of the conditions was the evidence convincing. Our conclusions therefore had to be cautious: due to a number of caveats, the evidence is not sufficiently convincing that aromatherapy is an effective therapy for any condition.

Finally, we also investigated the safety of aromatherapy by assessing all published data regarding adverse effects. Forty two primary reports met our inclusion criteria. In total, 71 patients had experienced adverse effects after aromatherapy which ranged from mild to severe and included one fatality. The most common adverse effect was dermatitis. Lavender, peppermint, tea tree oil and ylang-ylang were the most common essential oils responsible for adverse effects. We concluded that aromatherapy has the potential to cause adverse effects some of which are serious. Their frequency remains unknown.

And what is the conclusion of all this? To me, it seems fairly straight forward: Aromatherapy is not demonstrably effective for any condition. It also is not entirely free of risks. Its risk/benefit profile is thus not positive which can only mean that it is not a useful or recommendable treatment for anybody who is ill.

As I have mentioned before, I like positive news as much as the next person. Therefore, I am constantly on the look-out for recently published, sound evidence suggesting that  some form of alternative medicine is effective and safe for this or that condition. This new systematic review fits that description, I am pleased to report.

Its authors evaluated the effectiveness of massage therapy (MT) for neck and shoulder pain. Their extensive literature searches identified 12 high-quality studies. The meta-analyses showed significant effects of MT for neck pain and shoulder pain compared to inactive therapies. MT did not yield better effects for neck pain or shoulder pain than other active therapies administered to the control groups. Shoulder function was not significantly affected by MT. The authors concluded that “MT may provide immediate effects for neck and shoulder pain. However, MT does not show better effects on pain than other active therapies. No evidence suggests that MT is effective in functional status”.

Massage therapy is thus a promising treatment, particularly as this systematic review is by no means the only piece of encouraging evidence. It is not better than other effective treatments, but it is not associated with frequent or serious adverse effects. This means that the demonstrable benefits are likely to outweigh its risks; in other words, the risk benefit balance is positive. Regular readers of this blog will appreciate the importance of this point.

Massage is practiced by several professions: mostly, of course, by massage therapists, but occasionally also by nurses, osteopath, chiropractors etc. Chiropractors, in particular, have recently tried to make much – I think too much – of this fact. They tend to claim that, as they use treatments which are evidence-based, such as massage, chiropractic is an evidence-based profession. I think this is akin to surgeons claiming that all of surgery is evidence-based because surgeons use medications which effectively reduce post-operative pain. Chiropractors foremost employ spinal manipulation and surgeons foremost use surgery; if they want us to believe that their practice is evidence-based, they need to show us the evidence for their hall-mark interventions. In the case of surgery, the evidence is mostly established; in the case of chiropractic, it is mostly not.

Massage is backed by reasonably sound evidence not just for neck and shoulder pain but for a range of other conditions as well. WHAT DO WE CALL AN ALTERNATIVE MEDICINE THAT WORKS? WE CALL IT MEDICINE!

So why is massage not a mainstream therapy? The answer is simple: in many countries, massage therapy has long been considered to be entirely conventional. Twenty years ago, I was chair of rehabilitation medicine at the university of Vienna. Amongst my staff, there always were about 5-8 full time massage therapists and nobody thought this to be unusual in any way. Similarly, in Germany, massage is entirely conventional.

Perhaps it is time that the English-speaking countries catch up with Europe when it comes to massage therapy and the evidence that supports it?

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