MD, PhD, FMedSci, FSB, FRCP, FRCPEd

systematic review

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In 2009, we published a systematic review of studies testing acupuncture as a treatment of menopausal hot flushes. We searched the literature using 17 databases from inception to October 10, 2008, without language restrictions. We only included randomized clinical trials (RCTs) of acupuncture versus sham acupuncture. Their methodological quality was assessed using the modified Jadad score. In total, six RCTs could be included. Four RCTs compared the effects of acupuncture with penetrating sham acupuncture on non-acupuncture points. All of these trials failed to show specific effects on menopausal hot flush frequency, severity or index. One RCT found no effects of acupuncture on hot flush frequency and severity compared with penetrating sham acupuncture on acupuncture points that are not relevant for the treatment of hot flushes. The remaining RCT tested acupuncture against non-penetrating acupuncture on non-acupuncture points. Its results suggested favourable effects of acupuncture on menopausal hot flush severity. However, this study was too small to generate reliable findings. At the time, we concluded that sham-controlled RCTs fail to show specific effects of acupuncture for control of menopausal hot flushes. We also argued that more rigorous research is warranted.

It seems that such research has just become available.

The aim of a brand-new study – a stratified, blind (participants, outcome assessors, and investigators, but not treating acupuncturists were blinded to treatment allocation), parallel, randomized, sham-controlled trial with equal allocation – was to assess the efficacy of Chinese medicine acupuncture against sham acupuncture for menopausal hot flushes (HFs). It was funded by the Australian National Health and Medical Research Council.

Women older than 40 years were recruited; they had to be in the late menopausal transition or postmenopause with at least 7 moderate HFs daily, meeting criteria for Chinese medicine diagnosis of kidney yin deficiency. These patients received 10 treatments over 8 weeks of either standardized Chinese medicine needle acupuncture designed to treat ‘kidney yin deficiency’ or they got the same amount of non-insertive sham acupuncture. 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.

In total, 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 period were 15.36 in the acupuncture group and 15.04 in the sham group. No serious adverse events were reported.

The authors concluded that Chinese medicine acupuncture was not superior to non-insertive sham acupuncture for women with moderately severe menopausal HFs.

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.

In other words: ACUPUNCTURE IS NOTHING BUT A THEATRICAL PLACEBO.

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. Subsequently they will probably conduct their own trial which, because it is wide open to bias, will generate the finding they were hoping for.

This sequence of poor quality positive and high quality negative studies could go on ad infinitum.

This begs the question: how can such wasteful pseudo-research be stopped?

In theory, applications to ethics committees for research that is not aimed at answering open and important questions should get rejected. In practice, however, this is unlikely to happen. In my experience, the main reason preventing such actions is that, when it comes to alternative medicine, ethics committees tend to be too lenient (attempting to be ‘politically correct’), too uninterested (thinking that alternative medicine is not really a serious area of research) and too uninformed (failing to insist on a rigorous assessment of the already available evidence).

Many cancer patients use mistletoe extracts either hoping to cure their cancer or to alleviate its symptoms. The evidence that mistletoe treatment (MT) can achieve either of these goals is mixed but, on the whole, however, it is not positive. Our own systematic review of 2003 concluded that ‘rigorous trials of mistletoe extracts fail to demonstrate efficacy of this therapy’. The more recent Cochrane review concurred: ‘The evidence from RCTs to support the view that the application of mistletoe extracts has impact on survival or leads to an improved ability to fight cancer or to withstand anticancer treatments is weak.’

Patients’ experiences of side effects and the acceptability, tolerability, and perceived benefits of MT have not been assessed critically. The aim of this new article was to systematically review and synthesise the results of qualitative studies of cancer patients’ experiences of using MT.

Electronic searches were conducted in MEDLINE, Embase, PsychLIT, CINAHL, and AMED to identify all qualitative studies of MT. Articles were screened independently by two reviewers and critically appraised using the Critical Appraisal Skills Programme tool. A thematic synthesis of the findings was carried out.

One hundred and seventy-three papers were identified; 156 were excluded at initial screening. Seventeen papers were read in full, 14 of which were excluded. Three articles about patients’ experiences of MT alongside conventional treatment were included in the synthesis, either as a monotherapy (two articles) or as part of a package of anthroposophic treatment (one article). Patients reported demonstrable changes to their physical, emotional, and psychosocial well-being following MT, as well as a reduction in chemotherapy side effects. Self-reported side effects from MT were few, and the studies suggest good adherence to the therapy. Self-injection gave patients a sense of empowerment through involvement in their own treatment.

The authors concluded that ‘given the variation in context of MT delivery across the articles, it is not possible to ascribe changes in patients’ quality of life specifically to MT.’

This might be a polite way of saying that there is no good evidence to suggest that MT positively affects patients’ experiences of side effects and the acceptability, tolerability, and perceived benefits.

Mistletoe is, of course, the ‘flagship’ intervention of Rudolf Steiner’s anthroposophical medicine. About a century ago, his idea was simple (or should this be ‘simplistic’?): the mistletoe plant is a parasite that lives off host trees sapping its resources until, eventually, it might even kill its host – just like cancer threatening the life of a human being. It follows, according to the homeopathy-inspired Steiner and the many followers of his cult that mistletoe is an effective cancer therapy.

Despite the weirdness of this concept and the largely negative evidence, MT is hugely popular as a cancer cure, particularly in German-speaking countries. The question I ask myself is this: ISN’T IT TIME THAT THIS NONSENSE STOPS?

What a question, you might say. And you would be right, it’s a most awkward one, so much so that I cannot answer it for myself.

I NEED YOUR HELP.

Here is the story:

Ten years ago, with the help of S Lejeune and an EU grant, my team conducted a Cochrane review of Laertrile. To do the ‘ground work’, we hired an Italian research assistant, S Milazzo, who was supervised mainly by my research fellow Katja Schmidt. Consequently, the review was published under the names of all main contributors: Milazzo, Ernst, Lejeune, Schmidt.

In 2011, an update was due for which the help of Dr Markus Horneber, the head of a German research team investigating alt med in relation to cancer, was recruited. By then, Milazzo and Schmidt had left my unit and, with my consent, Horneber, Milazzo and Schmidt took charge of the review. I was then sent a draft of their update and did a revision of it which consisted mostly in checking the facts and making linguistic changes. The article was then published under the following authorship: Milazzo S, Ernst E, Lejeune S, Boehm K, Horneber M (Katja had married meanwhile, so Boehm and Schmidt are the same person).

A few days ago, I noticed that a further update had been published in 2015. Amazingly, I had not been told, asked to contribute, or informed that my name as co-author had been scrapped. The authors of the new update are simply Milazzo and Horneber (the latter being the senior author). Katja Boehm had apparently indicated that she did no longer want to be involved; I am not sure what happened to Lejeune.

I know Markus Horneber since donkey’s years and had co-authored several other papers with him in the past, so I (admittedly miffed about my discovery) sent him an email and asked him whether he did not consider this behaviour to amount to plagiarism. His reply was, in my view, unhelpful in explaining why I had not been asked to get involved and Horneber asked me to withdraw the allegation of plagiarism (which I had not even made) – or else he would take legal action (this was the moment when I got truly suspicious).

Next, I contacted the responsible editor at the Cochrane Collaboration, not least because Horneber had claimed that she had condoned the disputed change of authorship. Her reply confirmed that “excluding previous authors without giving them a chance to comment is not normal Cochrane policy” and that she did, in fact, not condone the omission of my name from the list of co-authors.

The question that I am asking myself (not for the first time, I am afraid – a similar, arguably worse case has been described in the comments section of this post) is the following: IS THIS A CASE OF PLAGIARISM OR NOT? In the name of honesty, transparency and science, it requires an answer, I think.

Even after contemplating it for several days, I seem to be unable to find a conclusive response. On the one hand, I did clearly not contribute to the latest (2015) update and should therefore not be a co-author. On the other hand, I feel that I should have been asked to contribute, in which case I would certainly have done so and remained a co-author.

For a fuller understanding of this case, I here copy the various sections of the abstracts of the 2011 update (marked OLD) and the 2015 update without my co-authorship (marked NEW):

 

OLD

Laetrile is the name for a semi-synthetic compound which is chemically related to amygdalin, a cyanogenic glycoside from the kernels of apricots and various other species of the genus Prunus. Laetrile and amygdalin are promoted under various names for the treatment of cancer although there is no evidence for its efficacy. Due to possible cyanide poisoning, laetrile can be dangerous.

NEW

Laetrile is the name for a semi-synthetic compound which is chemically related to amygdalin, a cyanogenic glycoside from the kernels of apricots and various other species of the genus Prunus. Laetrile and amygdalin are promoted under various names for the treatment of cancer although there is no evidence for its efficacy. Due to possible cyanide poisoning, laetrile can be dangerous.

OBJECTIVES:

OLD

To assess the alleged anti-cancer effect and possible adverse effects of laetrile and amygdalin.

NEW

To assess the alleged anti-cancer effect and possible adverse effects of laetrile and amygdalin.

SEARCH METHODS:

OLD

We searched the following databases: CENTRAL (2011, Issue 1); MEDLINE (1951-2011); EMBASE (1980-2011); AMED; Scirus; CancerLit; CINAHL (all from 1982-2011); CAMbase (from 1998-2011); the MetaRegister; the National Research Register; and our own files. We examined reference lists of included studies and review articles and we contacted experts in the field for knowledge of additional studies. We did not impose any restrictions of timer or language.

NEW

We searched the following databases: CENTRAL (2014, Issue 9); MEDLINE (1951-2014); EMBASE (1980-2014); AMED; Scirus; CINAHL (all from 1982-2015); CAMbase (from 1998-2015); the MetaRegister; the National Research Register; and our own files. We examined reference lists of included studies and review articles and we contacted experts in the field for knowledge of additional studies. We did not impose any restrictions of timer or language.

SELECTION CRITERIA:

OLD

Randomized controlled trials (RCTs) and quasi-RCTs.

NEW

Randomized controlled trials (RCTs) and quasi-RCTs.

DATA COLLECTION AND ANALYSIS:

OLD

We searched eight databases and two registers for studies testing laetrile or amygdalin for the treatment of cancer. Two review authors screened and assessed articles for inclusion criteria.

NEW

We searched eight databases and two registers for studies testing laetrile or amygdalin for the treatment of cancer. Two review authors screened and assessed articles for inclusion criteria.

MAIN RESULTS:

OLD

We located over 200 references, 63 were evaluated in the original review and an additional 6 in this update. However, we did not identify any studies that met our inclusion criteria.

NEW

We located over 200 references, 63 were evaluated in the original review, 6 in the 2011 and none in this update. However, we did not identify any studies that met our inclusion criteria.

AUTHORS’ CONCLUSIONS:

OLD

The claims that laetrile or amygdalin have beneficial effects for cancer patients are not currently supported by sound clinical data. There is a considerable risk of serious adverse effects from cyanide poisoning after laetrile or amygdalin, especially after oral ingestion. The risk-benefit balance of laetrile or amygdalin as a treatment for cancer is therefore unambiguously negative.

NEW

The claims that laetrile or amygdalin have beneficial effects for cancer patients are not currently supported by sound clinical data. There is a considerable risk of serious adverse effects from cyanide poisoning after laetrile or amygdalin, especially after oral ingestion. The risk-benefit balance of laetrile or amygdalin as a treatment for cancer is therefore unambiguously negative.

END OF ABSTRACT

I HOPE THAT YOU, THE READER OF THIS POST, ARE NOW ABLE TO TELL ME:

HAVE I BEEN PLAGIARISED?

P S

After the response from the Cochrane editor, I asked Horneber whether he wanted to make a further comment because I was thinking to blog about this. So far, I have not received a reply.

Some time ago, when we published our systematic review about the adverse effects associated with homeopathic remedies, there was an outcry of critics stating that it is not rational to claim, on the one hand, that homeopathic remedies are so dilute that they contain nothing and therefore do nothing and, on the other hand, that homeopathic remedies can cause side-effects. These people should, of course, have known better, but I admit it can be a little confusing. So, let me explain.

Every homeopathic remedy starts as a ‘mother tincture’. That is the undiluted stock prepared according to a homeopathic pharmacopoeia. The mother tincture is then diluted and shaken to give the first ‘potency’. Depending on the potency scale, this could be a ‘C1’ (1:100) or ‘D1’ (1:10). The resulting potency can be potentised again to give the second potency which can be potentised again to give the third potency. And this process of ‘serial dilution’ can be continued ad infinitum (the most common potency is the C30 which is a dilution of 30 times 1 : 100).

All of these remedies are by definition homeopathic, of course; even a mother tincture is strictly speaking a homeopathic remedy.

Now imagine we have a highly toxic stock, for instance, arsenic. This is by no means an extreme example, as many substances used in homeopathy are poisonous. A ‘D1’ of arsenic is both effective and dangerous: it is effective for killing rats and other unwanted creatures, and it is dangerous should a patient take it.

So, now we understand better why homeopathic remedies can, contrary to a common myth, cause direct adverse effects (in addition to the scenario outlined above, they can also be contaminated or adulterated, of course). We also realise that the ‘experts’ who protested against our review of side-effects of homeopathic remedies were either ignorant or stupid or both. Most importantly, we understand, I hope, that when we speak or write about the ineffectiveness of homeopathic remedies, we of course mean those that are too dilute to have any effect at all – and these are certainly the vast majority.

Chiropractors and osteopaths have long tried to convince us that spinal manipulation and mobilisation are the best we can do when suffering from neck pain. But is this claim based on good evidence?

This recent update of a Cochrane review was aimed at assessing the effects of manipulation or mobilisation alone compared with those of an inactive control or another active treatment on pain, function, disability, patient satisfaction, quality of life and global perceived effect in adults experiencing neck pain with or without radicular symptoms and cervicogenic headache (CGH) at immediate- to long-term follow-up, and when appropriate, to assess the influence of treatment characteristics (i.e. technique, dosage), methodological quality, symptom duration and subtypes of neck disorder on treatment outcomes.

Review authors searched the following computerised databases to November 2014 to identify additional studies: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). They also searched ClinicalTrials.gov, checked references, searched citations and contacted study authors to find relevant studies.

Randomised controlled trials (RCTs) undertaken to assess whether manipulation or mobilisation improves clinical outcomes for adults with acute/subacute/chronic neck pain were included in this assessment.

Two review authors independently selected studies, abstracted data, assessed risk of bias and applied Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methods (very low, low, moderate, high quality). The authors calculated pooled risk ratios (RRs) and standardised mean differences (SMDs).

Fifty-one trials with a total of 2920 participants could be included. The findings are diverse. Cervical manipulation versus inactive control: For subacute and chronic neck pain, a single manipulation (three trials, no meta-analysis, 154 participants, ranged from very low to low quality) relieved pain at immediate- but not short-term follow-up. Cervical manipulation versus another active treatment: For acute and chronic neck pain, multiple sessions of cervical manipulation (two trials, 446 participants, ranged from moderate to high quality) produced similar changes in pain, function, quality of life (QoL), global perceived effect (GPE) and patient satisfaction when compared with multiple sessions of cervical mobilisation at immediate-, short- and intermediate-term follow-up. For acute and subacute neck pain, multiple sessions of cervical manipulation were more effective than certain medications in improving pain and function at immediate- (one trial, 182 participants, moderate quality) and long-term follow-up (one trial, 181 participants, moderate quality). These findings are consistent for function at intermediate-term follow-up (one trial, 182 participants, moderate quality). For chronic CGH, multiple sessions of cervical manipulation (two trials, 125 participants, low quality) may be more effective than massage in improving pain and function at short/intermediate-term follow-up. Multiple sessions of cervical manipulation (one trial, 65 participants, very low quality) may be favoured over transcutaneous electrical nerve stimulation (TENS) for pain reduction at short-term follow-up. For acute neck pain, multiple sessions of cervical manipulation (one trial, 20 participants, very low quality) may be more effective than thoracic manipulation in improving pain and function at short/intermediate-term follow-up. Thoracic manipulation versus inactive control: Three trials (150 participants) using a single session were assessed at immediate-, short- and intermediate-term follow-up. At short-term follow-up, manipulation improved pain in participants with acute and subacute neck pain (five trials, 346 participants, moderate quality, pooled SMD -1.26, 95% confidence interval (CI) -1.86 to -0.66) and improved function (four trials, 258 participants, moderate quality, pooled SMD -1.40, 95% CI -2.24 to -0.55) in participants with acute and chronic neck pain. A funnel plot of these data suggests publication bias. These findings were consistent at intermediate follow-up for pain/function/quality of life (one trial, 111 participants, low quality). Thoracic manipulation versus another active treatment: No studies provided sufficient data for statistical analyses. A single session of thoracic manipulation (one trial, 100 participants, moderate quality) was comparable with thoracic mobilisation for pain relief at immediate-term follow-up for chronic neck pain. Mobilisation versus inactive control: Mobilisation as a stand-alone intervention (two trials, 57 participants, ranged from very low to low quality) may not reduce pain more than an inactive control. Mobilisation versus another active treatment: For acute and subacute neck pain, anterior-posterior mobilisation (one trial, 95 participants, very low quality) may favour pain reduction over rotatory or transverse mobilisations at immediate-term follow-up. For chronic CGH with temporomandibular joint (TMJ) dysfunction, multiple sessions of TMJ manual therapy (one trial, 38 participants, very low quality) may be more effective than cervical mobilisation in improving pain/function at immediate- and intermediate-term follow-up. For subacute and chronic neck pain, cervical mobilisation alone (four trials, 165 participants, ranged from low to very low quality) may not be different from ultrasound, TENS, acupuncture and massage in improving pain, function, QoL and participant satisfaction at immediate- and intermediate-term follow-up. Additionally, combining laser with manipulation may be superior to using manipulation or laser alone (one trial, 56 participants, very low quality).

Confused? So am I!

In my view, these analyses show that the quality of most studies is wanting and the evidence is weak – much weaker than chiropractors and osteopaths try to make us believe. It seems to me that no truly effective treatments for neck pain have been discovered and that therefore manipulation/mobilisation techniques are as good or as bad as most other options.

In such a situation, it might be prudent to first investigate the causes of neck pain in greater detail  and subsequently determine the optimal therapies for each of them. Neck pain is a SYMPTOM, not a disease! And it is always best to treat the cause of a symptom rather than pretending we know the cause as chiropractors and osteopaths often do.

The authors of the Cochrane review seem to agree with this view at least to some extent. They conclude that although support can be found for use of thoracic manipulation versus control for neck pain, function and QoL, results for cervical manipulation and mobilisation versus control are few and diverse. Publication bias cannot be ruled out. Research designed to protect against various biases is needed. Findings suggest that manipulation and mobilisation present similar results for every outcome at immediate/short/intermediate-term follow-up. Multiple cervical manipulation sessions may provide better pain relief and functional improvement than certain medications at immediate/intermediate/long-term follow-up. Since the risk of rare but serious adverse events for manipulation exists, further high-quality research focusing on mobilisation and comparing mobilisation or manipulation versus other treatment options is needed to guide clinicians in their optimal treatment choices.

The call for further research is, of course, of no help for patients who are suffering from neck pain today. What would I recommend to them?

My advice is to be cautious:

  • Consult your doctor and try to get a detailed diagnosis.
  • See a physiotherapist and ask to be shown exercises aimed at reducing the pain and preventing future episodes.
  • Do these exercises regularly, even when you have no pain.
  • Make sure you do whatever else might be needed in terms of life-style changes (ergonomic work place, correct sleeping arrangements, etc.).
  • If you are keen on seeing an alternative practitioner for manual therapy, consult a osteopath rather than a chiropractor; the former tend to employ techniques which are less risky than the latter.
  • Avoid both chiropractors and long-term medication for neck pain.

Don’t get me wrong, I have nothing against systematic reviews. Quite to the contrary, I am sure they are an important source of information for patients, doctors, scientists, policy makers and others – after all, I have published more than 300 of such papers!

Having said that, I do dislike a certain type of systematic review, namely systematic reviews by Chinese authors evaluating TCM therapies and arriving at misleading conclusions. Such papers are currently swamping the marked.

At first glance, they look fine. On closer scrutiny, however, most turn out to be stereotypically useless, boring and promotional. The type of article I mean starts by stating its objective which usually is to evaluate the evidence for a traditional Chinese therapy as a treatment of a condition which few people in their right mind would treat with any form of TCM. It continues with details about the methodologies employed and then, in the results section, informs the reader that x studies were included in the review which mostly reported encouraging results but were wide open to bias. And then comes the crucial bit: THE CONCLUSIONS.

They are as predictable as they are misleading. let me give you two examples only published in the last few days.

The first review drew the following conclusions: This systematic review suggests that Chinese Herbal Medicine as an adjunctive therapy can improve cognitive impairment and enhance immediate response and quality of life in Senile Vascular Dementia patients. However, because of limitations of methodological quality in the included studies, further research of rigorous design is needed.

The second review concluded that the evidence that external application of traditional Chinese medicine is an effective treatment for venous ulcers is encouraging, but not conclusive due to the low methodological quality of the RCTs. Therefore, more high-quality RCTs with larger sample sizes are required.

Why does that sort of thing frustrate me so much? Because it is utterly meaningless and potentially harmful:

  • I don’t know what treatments the authors are talking about.
  • Even if I managed to dig deeper, I cannot get the information because practically all the primary studies are published in obscure journals in Chinese language.
  • Even if I  did read Chinese, I do not feel motivated to assess the primary studies because we know they are all of very poor quality – too flimsy to bother.
  • Even if they were formally of good quality, I would have my doubts about their reliability; remember: 100% of these trials report positive findings!
  • Most crucially, I am frustrated because conclusions of this nature are deeply misleading and potentially harmful. They give the impression that there might be ‘something in it’, and that it (whatever ‘it’ might be) could be well worth trying. This may give false hope to patients and can send the rest of us on a wild goose chase.

So, to ease the task of future authors of such papers, I decided give them a text for a proper EVIDENCE-BASED conclusion which they can adapt to fit every review. This will save them time and, more importantly perhaps, it will save everyone who might be tempted to read such futile articles the effort to study them in detail. Here is my suggestion for a conclusion soundly based on the evidence, not matter what TCM subject the review is about:

OUR SYSTEMATIC REVIEW HAS SHOWN THAT THERAPY ‘X’ AS A TREATMENT OF CONDITION ‘Y’ IS CURRENTLY NOT SUPPORTED BY SOUND EVIDENCE.

The search for an effective treatment of obesity is understandably intense. Many scientists are looking in the plant kingdom for a solution, but so far none has been forthcoming – as we have already discussed on this blog before (e. g. here, and here). One herbal slimming aid is currently becoming popular: Yerba Mate also called Ilex paraguariensis, a plant many of us know from teas and other beverages. Our review concluded that the evidence for it was unconvincing but that it merited further study. This was 10 years ago, and meanwhile the evidence has moved on.

The aim of a recent study was to investigate the efficacy of Yerba Mate supplementation in subjects with obesity. For this purpose, a randomized, double-blind, placebo-controlled trial was conducted. Korean subjects with obesity (body mass index (BMI) ≥ 25 but < 35 kg/m(2) and waist-hip ratio (WHR) ≥ 0.90 for men and ≥ 0.85 for women) were given oral supplements of Yerba Mate capsules (n = 15) or placebos (n = 15) for 12 weeks. They took three capsules per each meal, total three times in a day (3 g/day). Outcome measures were efficacy (abdominal fat distribution, anthropometric parameters and blood lipid profiles) and safety (adverse events, laboratory test results and vital signs).

During 12 weeks of Yerba Mate supplementation, statistically significant decreases in body fat mass and percent body fat compared to the placebo group were noted significant. The WHR was significantly also decreased in the Yerba Mate group compared to the placebo group. No clinically significant changes in any safety parameters were observed.

The authors concluded that Yerba Mate supplementation decreased body fat mass, percent body fat and WHR. Yerba Mate was a potent anti-obesity reagent that did not produce significant adverse effects. These results suggested that Yerba Mate supplementation may be effective for treating obese individuals.

These are encouraging results, but the conclusions go way too far, for my taste. The study was tiny and does therefore not lend itself to far-reaching generalisations. What would be helpful, is a review of other evidence. As it happens, such a paper has just become available. Its authors evaluated the impact of yerba maté on obesity and obesity-related inflammation and demonstrate that yerba maté suppresses adipocyte differentiation as well as triglyceride accumulation and reduces inflammation. Animal studies show that yerba maté modulates signaling pathways that regulate adipogenesis, antioxidant, anti-inflammatory and insulin signaling responses.

The review authors concluded that the use of yerba maté might be useful against obesity, improving the lipid parameters in humans and animal models. In addition, yerba maté modulates the expression of genes that are changed in the obese state and restores them to more normal levels of expression. In doing so, it addresses several of the abnormal and disease-causing factors associated with obesity. Protective and ameliorative effects on insulin resistance were also observed… it seems that yerba maté beverages and supplements might be helpful in the battle against obesity.

I am still not fully convinced that this dietary supplement is the solution to the current obesity epidemic. But the evidence is encouraging – more so than for most of the many other ‘natural’ slimming aids that are presently being promoted for this condition by gurus like Dr Oz.

What we needed now is not the ill-informed, self-interested voice of charlatans; what we need is well-designed research to define efficacy, effect size and risks.

Recently an interesting article caught my eye. It was published in the official journal of the ‘Deutscher Zentralverein Homoeopathischer Aerzte’ (the professional body of German doctor homeopath which mostly acts as a lobby group). Unfortunately it is in German – but I will try to take you through what I believe to be the most important issue.

The article seems to have the aim to defame Natalie Grams, the homeopath who had the courage to change her mind about homeopathy and to even write a book about her transformation. This book impressed me so much that I wrote a post about it when it was first published. The book did, however, not impress her ex-colleagues. Consequently the book review by the German lobbyists is full of personal attacks and almost devoid of credible facts.

A central claim of the defamatory piece is that, contrary to what she claims in her book, homeopathy is supported by sound evidence. Here is the crucial quote: Meta-Analysen von Kleijnen (1991), Linde (1997), Cucherat (2000) und Mathie (2014) [liefern] allesamt positive Ergebnisse zur Wirksamkeit der Homöopathie… This translates as follows: meta-analyses of Kleijnen, Linde, Cucherat and Matie all provide positive results regarding the effectiveness of homeopathy. As this is a claim, we hear ad nauseam whenever we discuss the issue with homeopathy (in the UK, most homeopathic bodies and even the Queen’s homeopath, P Fisher, have issued very similar statements), it may be worth addressing it once and for all.

  • CUCHERAT

This paper was the result of an EU-funded project in which I was involved as well; I therefore know about it first hand. The meta-analysis itself is quite odd in that it simply averages the p-values of all the included studies and thus provides a new overall p-value across all trials. As far as I know, this is not an accepted meta-analytic method and seems rather a lazy way of doing the job. The man on our EU committee was its senior author, professor Boissel, who did certainly not present it to us as a positive result for homeopathy (even Peter Fisher who also was a panel member should be able to confirm this). What is more, the published conclusions are not nearly as positive as out lobbyists seem to think: ‘There is some evidence that homeopathic treatments are more effective than placebo; however, the strength of this evidence is low because of the low methodological quality of the trials. Studies of high methodological quality were more likely to be negative than the lower quality studies. Further high quality studies are needed to confirm these results.’

Anybody who claims this is a proof for homeopathy’s efficacy should be sent back to school to learn how to read and understand English, in my view.
  • LINDE

The meta-analysis by Linde et al seems to be the flag-ship in the homeopathic fleet. For those who don’t know it, here is its abstract in full:

BACKGROUND: Homeopathy seems scientifically implausible, but has widespread use. We aimed to assess whether the clinical effect reported in randomised controlled trials of homeopathic remedies is equivalent to that reported for placebo.

METHODS: We sought studies from computerised bibliographies and contracts with researchers, institutions, manufacturers, individual collectors, homeopathic conference proceedings, and books. We included all languages. Double-blind and/or randomised placebo-controlled trials of clinical conditions were considered. Our review of 185 trials identified 119 that met the inclusion criteria. 89 had adequate data for meta-analysis, and two sets of trial were used to assess reproducibility. Two reviewers assessed study quality with two scales and extracted data for information on clinical condition, homeopathy type, dilution, “remedy”, population, and outcomes.

FINDINGS: The combined odds ratio for the 89 studies entered into the main meta-analysis was 2.45 (95% CI 2.05, 2.93) in favour of homeopathy. The odds ratio for the 26 good-quality studies was 1.66 (1.33, 2.08), and that corrected for publication bias was 1.78 (1.03, 3.10). Four studies on the effects of a single remedy on seasonal allergies had a pooled odds ratio for ocular symptoms at 4 weeks of 2.03 (1.51, 2.74). Five studies on postoperative ileus had a pooled mean effect-size-difference of -0.22 standard deviations (95% CI -0.36, -0.09) for flatus, and -0.18 SDs (-0.33, -0.03) for stool (both p < 0.05).

INTERPRETATION: The results of our meta-analysis are not compatible with the hypothesis that the clinical effects of homeopathy are completely due to placebo. However, we found insufficient evidence from these studies that homeopathy is clearly efficacious for any single clinical condition. Further research on homeopathy is warranted provided it is rigorous and systematic.

Again, the conclusions are not nearly as strongly in favour of homeopaths as the German lobby group assumes. Moreover, this paper has been extensively criticised for a wide range of reasons which I shall not have to repeat here. However, one point is often over-looked: this is not an assessment of RCTs, it is an analysis of studies which were double-blind and/or randomised and placebo-controlled. This means that it includes trials that were not randomised and studies that were not double-blind.

But this is just by the way. What seems much more important is the fact that, in response to the plethora of criticism to their article, the same authors published a re-analysis of exactly the same data-set two years later. Having considered the caveats and limitations more carefully, they now concluded that ‘in the study set investigated, there was clear evidence that studies with better methodological quality tended to yield less positive results.’

It is most intriguing to see how homeopaths cite their ‘flagship’ on virtually every possible occasion, while forgetting that a quasi correction has been published which puts the prior conclusions in a very different light !

  • KLEIJNEN

The much-cited article by Kleijnen is now far too old to be truly relevant. It includes not even half of the trials available today. But, for what it’s worth, here are Kleijnen’s conclusions: At the moment the evidence of clinical trials is positive but not sufficient to draw definitive conclusions because most trials are of low methodological quality and because of the unknown role of publication bias. This indicates that there is a legitimate case for further evaluation of homoeopathy, but only by means of well performed trials.

If the homeopathy lobby today proclaims that this paper constitutes proof of efficacy, they are in my view deliberately misleading the public.

  • MATHIE

The Mathie meta-analysis has been extensively discussed on this blog (see here and here). It is not an overall meta-analysis but merely evaluates the subset of those trials that employed individualised homeopathy. Crucially, it omits the two most rigorous studies which happen to be negative. Its conclusions are as follows: ‘Medicines prescribed in individualised homeopathy may have small, specific treatment effects. Findings are consistent with sub-group data available in a previous ‘global’ systematic review. The low or unclear overall quality of the evidence prompts caution in interpreting the findings. New high-quality RCT research is necessary to enable more decisive interpretation.’

Again, I would suggest that anyone who interprets this as stating that this provides ‘positive results regarding the effectiveness of homeopathy’ is not telling the truth.

MY CONCLUSIONS FROM ALL THIS:

  1.  Some systematic reviews and meta-analyses do indeed suggest that the trial data are positive. However, they all caution that such a result might be false-positive.
  2. None of these papers provide anything near a proof for the effectiveness of homeopathy.
  3. Homeopathy has not been shown to be more than a placebo therapy.
  4. To issue statements to the contrary is dishonest.

If you start reading the literature on chiropractic, you are bound to have surprises. The paucity of rigorous and meaningful research is one of them. I am constantly on the look-out for such papers but am regularly frustrated. Over the years, I got the impression that chiropractors tend to view research as an exercise in promotion – that is promotion of their very own trade.

Take this article, for instance. It seems to be a systematic review of chiropractic for breastfeeding. This is an interesting indication; remember: in 1998, Simon Singh wrote in the Guardian this comment “The British Chiropractic Association claims that their members can help treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying, even though there is not a jot of evidence. This organisation is the respectable face of the chiropractic profession and yet it happily promotes bogus treatments.” As a consequence, he got sued for libel; he won, of course, but ever since, chiropractors across the world are trying to pretend that there is some evidence for their treatments after all.

The authors of the new review searched Pubmed [1966-2013], Manual, Alternative and Natural Therapy Index System (MANTIS) [1964-2013] and Index to Chiropractic Literature [1984-2013] for the relevant literature. The search terms utilized “breastfeeding”, “breast feeding”, “breastfeeding difficulties”, “breastfeeding difficulty”, “TMJ dysfunction”, “temporomandibular joint”, “birth trauma” and “infants”, in the appropriate Boolean combinations. They also examined non-peer-reviewed articles as revealed by Index to Chiropractic Literature and conducted a secondary analysis of references. Inclusion criteria for their review included all papers on breastfeeding difficulties regardless of peer-review. Articles were excluded if they were not written in the English language.

The following articles met the inclusion criteria: 8 case reports, 2 case series, 3 cohort studies and 6 manuscripts (5 case reports and a case series) that involved breastfeeding difficulties as a secondary complaint. The findings revealed a “theoretical and clinical framework based on the detection of spinal and extraspinal subluxations involving the cervico-cranio-mandibular complex and assessment of the infant while breastfeeding.”

Based on these results, the authors concluded that chiropractors care of infants with breastfeeding difficulties by addressing spinal and extraspinal subluxations involving the cervico-cranio-mandibular complex.

Have I promised too much?

I had thought that chiropractors had abandoned the subluxation nonsense! Not really, it seems.

I had thought that systematic reviews are about evidence of therapeutic effectiveness! Not in the weird world of chiropractic.

I would have thought that we all knew that ‘chiropractors care of infants with breastfeeding difficulties’ and do not need a review to confirm it! Yes, but what is good for business deserves another meaningless paper.

I would have thought that the conclusions of scientific articles need to be appropriate and based on the data provided! It seems that, in the realm of chiropractic, these rules do not apply.

An appropriate conclusion should have stated something like THERE IS NO GOOD EVIDENCE THAT CHIROPRACTIC CARE AIDS BREASTFEEDING. But that would have been entirely inappropriate from the chiropractic point of view because it is not a conclusion that promotes the sort of quackery most chiropractors rely upon for a living. And the concern over income is surely more important than telling the truth!

Much has been written on this blog and elsewhere about the risks of spinal manipulation. It relates almost exclusively to the risks of manipulating patients’ necks. There is far less on the safety of thrust joint manipulation (TJM) when applied to the thoracic spine. A new paper focusses on this specific topic.

The purpose of this review was to retrospectively analyse documented case reports in the literature describing patients who had experienced severe adverse events (AE) after receiving TJM to their thoracic spine.

Case reports published in peer reviewed journals were searched in Medline (using Ovid Technologies, Inc.), Science Direct, Web of Science, PEDro (Physiotherapy Evidence Database), Index of Chiropractic literature, AMED (Allied and Alternative Medicine Database), PubMed and the Cumulative Index to Nursing and Allied Health (CINHAL) from January 1950 to February 2015.

Case reports were included if they: (1) were peer-reviewed; (2) were published between 1950 and 2015; (3) provided case reports or case series; and (4) had TJM as an intervention. The authors only looked at serious complications, not at the much more frequent transient AEs after spinal manipulations. Articles were excluded if: (1) the AE occurred without TJM (e.g. spontaneous); (2) the article was a systematic or literature review; or (3) it was written in a language other than English or Spanish. Data extracted from each case report included: gender; age; who performed the TJM and why; presence of contraindications; the number of manipulation interventions performed; initial symptoms experienced after the TJM; as well as type of severe AE that resulted.

Ten cases, reported in 7 articles, were reviewed. Cases involved females (8) more than males (2), with mean age being 43.5 years. The most frequent AE reported was injury (mechanical or vascular) to the spinal cord (7/10); pneumothorax and hematothorax (2/10) and CSF leak secondary to dural sleeve injury (1/10) were also reported.

The authors point out that there were only a small number of case reports published in the literature and there may have been discrepancies between what was reported and what actually occurred, since physicians dealing with the effects of the AE, rather than the clinician performing the TJM, published the cases.

The authors concluded that serious AE do occur in the thoracic spine, most commonly, trauma to the spinal cord, followed by pneumothorax. This suggests that excessive peak forces may have been applied to thoracic spine, and it should serve as a cautionary note for clinicians to decrease these peak forces.

These are odd conclusions, in my view, and I think I ought to add a few points:

  • As I stated above, the actual rate of experiencing AEs after having chiropractic spinal manipulations is much larger; it is around 50%.
  • Most complications on record occur with chiropractors, while other professions are far less frequently implicated.
  • The authors’ statement about ‘excessive peak force’ is purely speculative and is therefore not a legitimate conclusion.
  • As the authors mention, it is  hardly ever the chiropractor who reports a serious complication when it occurs.
  • In fact, there is no functioning reporting scheme where the public might inform themselves about such complications.
  • Therefore their true rate is anyone’s guess.
  • As there is no good evidence that thoracic spinal manipulations are effective for any condition, the risk/benefit balance for this intervention fails to be positive.
  • Many consumers believe that a chiropractor will only manipulate in the region where they feel pain; this is not necessarily true – they will manipulate where they believe to diagnose ‘SUBLUXATIONS’, and that can be anywhere.
  • Finally, I would not call a review that excludes all languages other than English and Spanish ‘systematic’.

And my conclusion from all this? THORACIC SPINAL MANIPULATIONS CAN CAUSE CONSIDERABLE HARM AND SHOULD BE AVOIDED.

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