misleading consumers
The main aim of our systematic review was to estimate the prevalence of use of alternative medicine (AM) in the UK. Five databases were searched for peer-reviewed surveys published between 1 January 2000 and 7 October 2011. In addition, relevant book chapters and files from our own departmental records were searched by hand. Eighty-nine surveys were included, with a total of 97,222 participants. Surely, fact that this large amount of UK surveys had emerged in only about one decade, speaks for itself.
Most studies turned out to be of poor methodological quality. Across all surveys, the average one-year prevalence of AM-use was 41.1%, and the average lifetime prevalence was 51.8%. However, many of these investigations were flimsy. According to methodologically sound surveys, the equivalent rates were 26.3% and 44%, respectively. In surveys with response rates >70%, the average one-year prevalence was nearly threefold lower than in surveys with response rates below 50%. Herbal medicine was the most popular CAM, followed by homeopathy, aromatherapy, massage and reflexology.
To the best of my knowledge, this is the first time that four crucial points about such surveys have been clearly documented:
1) The amount of surveys in AM is staggering.
2) They contribute very little worthwhile knowledge and mostly seem to be exercises in AM-promotion.
3) Their methodological quality is usually low.
4) The poor quality surveys systematically over-estimate the prevalence of AM-use.
I think it is time that AM investigators focus on real research answering important questions which advance out knowledge, that AM-journal editors stop publishing meaningless nonsense, and that decision-makers understand the difference between promotion dressed up as science and real research.
Antioxidant vitamins include vitamin E, beta-carotene, and vitamin C. They are often recommended and widely used for preventing major cardiovascular outcomes. However, the effect of antioxidant vitamins on cardiovascular events remains unclear. There is plenty of evidence but the trouble is that it is not always of high quality and confusingly contradictory. Consequently, it is possible to cherry-pick the studies you prefer in order to come up with the answer you like. That this approach is counter-productive should be obvious to every reader of this blog. Only a rigorous systematic review can provide an answer that is as reliable as possible with the data available to date. Chinese researchers have just published such an assessment.
They searched PubMed, EmBase, the Cochrane Central Register of Controlled Trials, and the proceedings of major conferences for relevant investigations. To be eligible, studies had to be randomized, placebo-controlled trials reporting on the effects of antioxidant vitamins on cardiovascular outcomes. The primary outcome measures were major cardiovascular events, myocardial infarction, stroke, cardiac death, total death, and any adverse events.
The searches identified 293 articles of which 15 RCTs reporting data on 188209 participants met the inclusion criteria. In total, these studies reported 12749 major cardiovascular events, 6699 myocardial infarction, 3749 strokes, 14122 total death, and 5980 cardiac deaths. Overall, antioxidant vitamin supplementation, as compared to placebo, had no effect on major cardiovascular events (RR, 1.00; 95% CI, 0.96-1.03), myocardial infarction (RR, 0.98; 95% CI, 0.92-1.04), stroke (RR, 0.99; 95% CI, 0.93-1.05), total death (RR, 1.03; 95% CI, 0.98-1.07), cardiac death (RR, 1.02; 95% CI, 0.97-1.07), revascularization (RR, 1.00; 95% CI, 0.95-1.05), total CHD (RR, 0.96; 95% CI, 0.87-1.05), angina (RR, 0.98; 95% CI, 0.90-1.07), and congestive heart failure (RR, 1.07; 95% CI, 0.96 to 1.19).
The authors’ conclusion from these data could not be clearer: Antioxidant vitamin supplementation has no effect on the incidence of major cardiovascular events, myocardial infarction, stroke, total death, and cardiac death.
Few subjects in the realm of nutrition have attracted as much research during recent years as did antioxidants, and it is hard to think of a disease for which they are not recommended by this expert or another. Cardiovascular disease used to be the flag ship in this fleet of conditions; not so long ago, even the conventional medical wisdom sympathized with the notion that the regular supplementation of our diet with antioxidant vitamins might reduce the risk of cardiovascular disease and mortality.
Today, the pendulum has swung back, and it now seems to be mostly the alternative scene that still swears by antioxidants for that purpose. Nobody doubts that antioxidants have important biological functions, but this excellent meta-analysis quite clearly and fairly convincingly shows that buying antioxidant supplements is a waste of money. It does not promote cardiovascular health, it merely generates very expensive urine.
Even after all these years of full-time research into alternative medicine and uncounted exchanges with enthusiasts involved in this sector, I find the logic that is often applied in this field bewildering and the unproductiveness of the dialogue disturbing.
To explain what I mean, it be might best to publish a (fictitious, perhaps slightly exaggerated) debate between a critical thinker or scientist (S) and an uncritical proponent (P) of one particular form of alternative medicine.
P: Did you see this interesting study demonstrating that treatment X is now widely accepted, even by highly critical GPs at the cutting edge of health care?
S: This was a survey, not a ‘study’, and I never found the average GP “highly critical”. Surveys of this nature are fairly useless and they “demonstrate” nothing of real value.
P: Whatever, but it showed that GPs accept treatment X. This can only mean that they realise how safe and effective it is.
S: Not necessarily, GPs might just give in to consumer demand, or the sample was cleverly selected, or the question was asked in a leading manner, etc.
P: Hardly, because there is plenty of good evidence for treatment X.
S: Really? Show me.
P: There is this study here which proves that treatment X works and is risk-free.
S: The study was far too small to demonstrate safety, and it is wide open to multiple sources of bias. Therefore it does not conclusively show efficacy either.
P: You just say this because you don’t like its result! You have a closed mind!
In any case, it was merely an example! There are plenty more positive studies; do your research properly before you talk such nonsense.
S: I did do some research and I found a recent, high quality systematic review that arrived at a negative conclusion about the value of treatment X.
P: That review was done by sceptics who clearly have an axe to grind. It is based on studies which do not account for the intrinsic subtleties of treatment X. Therefore they are unfair tests of treatment X. These trials don’t really count at all. Every insider knows that! The fact that you cite it merely confirms that you do not understand what you are talking about.
S: It seems to me, that you like scientific evidence only when it confirms your belief. This, I am afraid, is what quacks tend to do!
P: I strongly object to being insulted in this way.
S: I did not insult you, I merely made a statement of fact.
P: If you like facts, you have to see that one needs to have sufficient expertise in treatment X in order to apply it properly and effectively. This important fact is neglected in all of those trials that report negative results; and that’s why they are negative. Simple! I really don’t understand why you are too stupid to understand this. Such studies do not show that treatment X is ineffective, but they demonstrate that the investigators were incompetent or hired with the remit to discredit treatment X.
S: I would have thought they are negative because they minimised bias and the danger of generating a false positive result.
P: No, by minimising bias, as you put it, these trials eliminated the factors that are important elements of treatment X.
S: Such as the placebo-effect?
P: That’s what you call it because you irrationally believe in reductionist science.
S: Science requires no belief, I think you are the believer here.
P: The fact is that scientists of your ilk negate all factors related to human interactions. Patients are no machines, you know, they need compassion; we clinicians know that because we work at the coal face of health care. Scientists in their ivory towers have no idea about patient care and just want science for science sake. This is not how you help patients. Show some compassion man!
S: I do know about the importance of compassion and care, but here we are discussing an entirely different topic, namely tests the efficacy or effectiveness of treatments, not patient-care. Let’s focus on one issue at a time.
P: You cannot separate things in this way. We have to take a holistic view. Patients are whole individuals, and you cannot do them justice by running artificial experiments. Every patient is different; clinical trials fail to account for this fact and are therefore fairly irrelevant to us and to our patients. Real life is very different from your imagined little experiments, you know.
S: These are platitudes that are nonsensical in this context and do not contribute anything meaningful to the present discussion. You do not seem to understand the methodology or purpose of a clinical trial.
P: That is typical! Whenever you run out of arguments, you try to change the subject or throw a few insults at me.
S: Not at all, I thought we were talking about clinical trials evaluating the effectiveness of treatment X.
P: That’s right; and they do show that it is effective, provided you consider those which are truly well-done by experts who know about treatment X and believe in it.
S: Not true. Only if you cherry-pick the data will you be able to produce an overall positive result for treatment X.
P: In any case, the real world results of clinical practice show very clearly that it works. It would not have survived for so long, if it didn’t. Nobody can deny that, and nobody should claim that silly little trials done in artificial circumstances are more meaningful than a wealth of experience.
S: Experience has little to do with reliable evidence.
P: To deny the value of experience is just stupid and clearly puts you in the wrong. I have shown you plenty of reliable evidence but you just ignore everything I say that does not go along with your narrow-minded notions about science; science is not the only way of knowing or comprehending things! Stop being obsessed with science.
S: No, you show me rubbish data and have little understanding of science, I am afraid.
P: Here we go again! I have had about enough of that and your blinkered arguments. We are going in circles because you are ignorant and arrogant. I have tried my best to show you the light, but your mind is closed. I offer true insight and you pay me back with insults. You and your cronies are in the pocket of BIG PHARMA. You are cynical, heartless and not interested in the wellbeing of patients. Next you will tell me to vaccinate my kids!
S: I think this is a waste of time.
P: Precisely! Everyone who has followed this debate will see very clearly that you are obsessed with reductionist science and incapable of considering the suffering of whole individuals. You want to deny patients a treatment that really helps them simply because you do not understand how treatment X works. Shame on you!!!
According to the UK General Osteopathic Council, osteopathy is a system of diagnosis and treatment for a wide range of medical conditions. It works with the structure and function of the body, and is based on the principle that the well-being of an individual depends on the skeleton, muscles, ligaments and connective tissues functioning smoothly together.
To an osteopath, for your body to work well, its structure must also work well. So osteopaths work to restore your body to a state of balance, where possible without the use of drugs or surgery. Osteopaths use touch, physical manipulation, stretching and massage to increase the mobility of joints, to relieve muscle tension, to enhance the blood and nerve supply to tissues, and to help your body’s own healing mechanisms. They may also provide advice on posture and exercise to aid recovery, promote health and prevent symptoms recurring.
In case this sounds a bit vague to you, and in case you wonder what this “wide range of conditions” might be, rest assured, you are not alone. So let’s try to be a little more concrete and clear up some of the confusion around this profession. There are two very different types of osteopaths: US osteopaths are virtually identical with conventionally trained physicians; their qualification is equivalent to those of medical practitioners and they can, for instance, specialise to become GPs or neurologists or surgeons etc. Elsewhere, osteopaths are non-medically qualified alternative practitioners. In the UK, they are regulated by statute, in other counties not. And as to the “wide range of conditions”, I am not aware of any disease or symptom for which the evidence is convincing.
Osteopaths most commonly treat patients suffering from Chronic Non-Specific Low Back Pain (CNSLBP) using a set of non-drug interventions, particularly manual therapies such as spinal mobilisation and manipulation. The question is how well are these techniques supported by reliable evidence. To answer it, we must not cherry-pick our evidence but we need to consider the totality of the reliable studies; in other words, we need an up-to-date systematic review. Such an assessment of clinical research into osteopathic intervention for CNSLBP was recently published by Australian experts.
A thorough search of the literature in multiple electronic databases was undertaken, and all articles were included that reported clinical trials; had adult participants; tested the effectiveness and/or efficacy of osteopathic manual therapies applied by osteopaths, and had a study condition of CNSLBP. The quality of the trials was assessed using the Cochrane criteria. Initial searches located 809 papers, 772 of which were excluded on the basis of abstract alone. The remaining 37 papers were subjected to a detailed analysis of the full text, which resulted in 35 further articles being excluded. There were thus only two studies assessing the effectiveness of manual therapies applied by osteopaths in adult patients with CNSLBP. The results of one trial suggested that the osteopathic intervention was similar in effect to a sham intervention, and the other implies equivalence of effect between osteopathic intervention, exercise and physiotherapy.
I guess, this comes as a bit of a surprise to many consumers who have been told over and over again by osteopaths and their supporters that the evidence is sound. Personally, I am not at all surprised because, two years ago, we published a similar review, albeit with a wider spectrum of conditions, namely any type of musculoskeletal pain. We managed to include a total of 16 RCTs. Five of them suggested that osteopathy leads to a significantly stronger reduction of musculoskeletal pain than a range of control interventions. However, 11 RCTs indicated that osteopathy, compared to controls, generates no change in musculoskeletal pain. At the time, we felt that these data fail to produce compelling evidence for the effectiveness of osteopathy as a treatment of musculoskeletal pain.
This lack of convincing evidence is in sharp contrast to the image of osteopaths as back pain specialists. The UK General Osteopathic council, for instance, sates that Osteopaths’ patients include the young, older people, manual workers, office professionals, pregnant women, children and sports people. Patients seek treatment for a wide variety of conditions, including back pain…In addition, thousands of websites try to convince the consumer that osteopathy is a well-proven therapy for chronic low back pain – not to mention the many other conditions for which the evidence is even less sound.
As so often in alternative medicine, these claims seem to be based more on wishful thinking than on reliable evidence. And as so often, the victims of bogus claims are the consumers who are being misled into making wrong therapeutic decisions, wasting money, and delaying recovery from illness.
Alternative medicine has the image of being gentle and risk-free; it is therefore frequently used for children. German experts have just published an important article on this rather controversial topic.
They performed a systematic synthesis of all Cochrane reviews in paediatrics assessing the efficacy, clinical implications and limitations of alternative medicine use in children. The main outcome variables were: percentage of reviews concluding that a certain intervention provides a benefit, percentage of reviews concluding that a certain intervention should not be performed, and percentage of studies concluding that the current level of evidence is inconclusive. A total of 135 reviews were included – most from the United Kingdom (29), Australia (24) and China (24). Only 5 (3.7%) reviews gave a recommendation in favour of a certain intervention; 26 (19.4%) issued a conditional positive recommendation. The 5 positive recommendations were:
1) Calcium supplements during pregnancy for prevention of hypertension and related conditions
2) Creatinine supplements for treating muscular disorders
3) Zinc supplements for prevention of pneumonia
4) Probiotics for prevention of upper respiratory infections
5) Acupuncture for prevention of post-operative nausea and vomiting
Nine (6.6%) reviews concluded that certain interventions should not be performed. Ninety-five reviews (70.3%) were inconclusive. The proportion of inconclusive reviews increased over time. The three most common criticisms of the quality of the primary studies included were: more research needed (82), low methodological quality (57) and small number of study participants (48).
The authors concluded: Given the disproportionate number of inconclusive reviews, there is an ongoing need for high quality research to assess the potential role of CAM in children. Unless the study of CAM is performed to the same science-based standards as conventional therapies, CAM therapies risk being perpetually marginalised by mainstream medicine.
As it happens, we published a very similar review two years ago. At the time (and using slightly different inclusion criteria), we identified a total of 17 systematic reviews. They related to acupuncture, chiropractic, herbal medicine, homeopathy, hypnotherapy, massage and yoga. Results were unconvincing for most conditions, but there was some evidence to suggest that acupuncture may be effective for postoperative nausea and vomiting, and that hypnotherapy may be effective in reducing procedure-related pain. Most of the reviews failed to mention the incidence of adverse effects of the alternative treatments in question. Our conclusions were as follows: “Although there is some encouraging evidence for hypnosis, herbal medicine and acupuncture, there is insufficient evidence to suggest that other CAMs are effective for the treatment of childhood conditions. Many of the systematic reviews included in this overview were of low quality, as were the randomised clinical trials within those reviews, further reducing the weight of that evidence. Future research in CAM for children should conform to the reporting standards outlined in the CONSORT and PRISMA guidelines.”
Treating children with unproven or dis-proven therapies is even more problematic than treating adults in this way. The main reason is that children cannot give informed consent. Thus alternative medicine for children can open difficult ethical questions, and sometimes I wonder where the line is between the application of bogus treatments and child-abuse. Examples are parents who opt for homeopathic vaccinations instead of conventional ones, or paediatric cancer patients who are being treated with bogus alternatives such as laetrile.
Why would parents not want the most effective therapy for their children? Why would anyone opt for dubious alternatives? The main reason, I think, must be misinformation. Parents who use alternative medicine are convinced they are effective and safe because they have been misinformed. We only need to google ALTERNATIVE MEDICINE to see for ourselves what utter nonsense and dangerous rubbish is being promoted under this umbrella.
Misinformation is the foremost reason why well-meaning parents (mis-) treat their children with alternative medicine. The results can be disastrous. Misinformation can kill!
Ignaz von Peczely (1826-1911), a Hungarian physician, got the idea for iridology (or iris-diagnosis) more than a century ago, after seeing streaks in the iris of a man he was treating for a broken leg, and similar phenomena the iris of an owl whose leg von Peczely had broken many years before. He subsequently became convinced that his method was able to distinguish between healthy organs and those that are overactive, inflamed, or distressed. Iridology became internationally known when US chiropractors began adopting this method in their clinical practice. In the United States, most insurance programs do not cover iridology but, in some European countries, they often do. In Germany, for instance, 80% of the Heilpraktiker (non-medically qualified health practitioners) practice iridology.
Iridologists claim to be able to diagnose the health status of an individual, medical conditions or predispositions to disease through abnormalities of pigmentation in the iris. The popularity of iridology renders it necessary to ask whether this method is valid.
The aim of my systematically review from 1999 was to critically evaluate all available, reliable tests of iridology as a diagnostic tool. Four case control studies were included; these are investigations where iridologists are asked to tell by looking at the iris of individuals whether that person does or does not have a certain condition. The majority of these studies suggested that iridology is not a valid diagnostic method. Back then, I concluded that “the validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.”
Since the publication of my article, several further studies have emerged:
One German team conducted a study investigating the applicability of iridology as a screening method for colorectal cancer. Digital color slides were obtained from both eyes of 29 patients with histologically diagnosed colorectal cancer and from 29 age- and gender-matched healthy control subjects. The slides were presented in random order to acknowledged iridologists without knowledge of the number of patients in the two categories. The iridologists correctly detected 51.7% and 53.4%, respectively, of the patients’ slides; therefore, the likelihood was statistically no better than chance. Sensitivity was, respectively, 58.6% and 55.2%, and specificity was 44.8% and 51.7%. The authors’ conclusion was blunt: “Iridology had no validity as a diagnostic tool for detecting colorectal cancer in this study.”
A study from South Africa aimed to determine the efficacy of iridology in the identification of moderate to profound sensorineural hearing loss in adolescents. A controlled trial was conducted with an iridologist, blind to the actual hearing status of participants, analysing the irises of participants with and without hearing loss. Fifty hearing impaired and fifty normal hearing subjects, between the ages of 15 and 19 years, controlled for gender, participated in the study. An experienced iridologist analysed the randomised set of participants’ irises. A 70% correct identification of hearing status was obtained with a false negative rate of 41% compared to a 19% false positive rate. The respective sensitivity and specificity rates therefore were 59% and 81%. The authors of this investigation concluded that “iridological analysis of hearing status indicated a statistically significant relationship to actual hearing status (P < 0.05). Although statistically significant sensitivity and specificity rates for identifying hearing loss by iridology were not comparable to those of traditional audiological screening procedures.”
A further German study investigated the value of iridology as a diagnostic tool in detecting some common cancers. One hundred ten subjects were enrolled; 68 subjects had histologically proven cancers of the breast, ovary, uterus, prostate, or colorectum, and 42 were cancer-free controls. All subjects were examined by an experienced practitioner of iridology, who was unaware of their medical details. He was allowed to suggest up to five diagnoses for each subject and his results were then compared with each subject’s medical diagnosis to determine the accuracy of iridology in detecting malignancy. Iridology identified the correct diagnosis in only 3 cases (sensitivity, 0.04). The authors concluded that “iridology was of no value in diagnosing the cancers investigated in this study.”
Based on these results it is impossible, I think, to claim that iridology is a valid or useful diagnostic tool. As there is no anatomical or physiological basis for its assumptions, iridology is not biologically plausible. Furthermore, the available clinical evidence does not support its validity as a diagnostic tool. In other words, iridology is bogus. This statement is in sharp contract to the information consumers receive about the method on uncounted websites, books, articles, etc. One website picked at random provides the following information:
The iris reveals changing conditions of every part and organ of the body. Every organ and part of the body is represented in the iris in a well defined area. In addition, through various marks, signs, and discoloration in the iris, nature reveals inherited weaknesses and strengths.
By means of this art / science, an iridologist (one who studies the coloration and fiber structure of the eye) can tell an individual his/her inherited and acquired tendencies towards health and disease, his current condition in general, and the state of every organ in particular.
Iridology cannot detect a specific disease, but, can tell an individual if they have over or under activity in specific areas of the body. For example, an under-active pancreas might indicate a diabetic condition.
Another source claims:
The underlying platform of iridology is that that eyes act as a ‘window’ to a person’s health & well being. This ‘window’ enables the practitioner to see whether areas or organs within the body are healthy, inflamed or ‘over active’. It also enables them to assess a person’s past/ possible future health problems & consider if the patient has a susceptibility to certain diseases. It is important to understand that iridology is simply a method of diagnosis & analysis.
You may well think that none of this really matters. Who cares whether iridology is bogus or not! I would argue that it does matter. Bogus methods cost money that could be better spent elsewhere. More importantly, false positive and false negative diagnoses generated by bogus diagnostic methods can put lives at risk.
But there is a more general and perhaps more crucial point here: alternative medicine is an area where people far too easily get away with ignoring the published evidence and scientific consensus. In the last two decades, I have seen many alternative modalities getting scientifically dis-proven; not in a single such instance can I remember that the corresponding alternative practitioners and their professional organisations took any notice of this fact, and not once did I notice that their practice had changed.
If research is systematically ignored, it becomes a useless appendix. More importantly, progress is then stifled to the detriment of all our best interests.
Indian homeopaths recently published a clinical trial aimed at evaluating homeopathic treatment in the management of diabetic polyneuropathy. The condition affects many diabetic patients; its symptoms include tingling, numbness, burning sensation in the feet and pain, particularly at night. The best treatment consists of adequate metabolic control of the underlying diabetes. The pain can be severe often does not respond adequately to conventional pain-killers. It is therefore obvious that any new, effective treatment would be more than welcome.
The new trial is a prospective observational study which was carried out from October 2005 to September 2009 by the Indian Central Council for Research in Homeopathy at its five Institutes. Patients suffering diabetic polyneuropathy (DPN) were screened and enrolled in the study, if they fulfilled the inclusion and exclusion criteria. The Diabetic Distal Symmetric Polyneuropathy Symptom Score (DDSPSS), developed by the Council, served as the primary outcome measure.
A total of 15 homeopathic medicines were identified after repertorizing the nosological symptoms and signs of the disease. The appropriate constitutional medicine was selected and prescribed in the 30, 200 and 1 M potencies on an individualized basis. Patients were followed up for 12 months.
Of 336 diabetics enrolled in the study, 247 patients who attended at least three follow-up appointments and baseline nerve conduction studies were included in the analysis. A statistically significant improvement in DDSPSS total score was found at 12 months. Most objective measures did not show significant improvements. Lycopodium clavatum (n = 132), Phosphorus (n = 27) and Sulphur (n = 26) were the most frequently prescribed homeopathic remedies.
From these results, the authors concluded that: “homeopathic medicines may be effective in managing the symptoms of DPN patients.”
Does this study tell us anything worth knowing? The short answer to this question, I am afraid, is NO.
Its weaknesses are all too obvious:
1) There was no control group.
2) Patients who did not come back to the follow-up appointments – presumably because they were not satisfied – were excluded from the analyses. The average benefit reported is thus likely to be a cherry-picked false positive result.
3) The primary outcome measure was not validated.
4) The observed positive effect on subjective symptoms could be due to several factors which are entirely unrelated to the homeopathic treatments’ e.g. better metabolic control, regression towards the mean, or social desirability.
Anyone who had seen the protocol of this study would have predicted the result; I see no way that such a study does not generate an apparently positive outcome. In other words, conducting the investigation was superfluous, which means that the patients’ participation was in vain; and this, in turn, means that the trial was arguably unethical.
This might sound a bit harsh, but I am entirely serious: deeply flawed research should not happen. It is a waste of scarce resources and patients’ tolerance; crucially, it has a powerful potential to mislead us and to set back our efforts to improve health care. All of this is unethical.
The problem of research which is so poor that it crosses the line into being unethical is, of course, not confined to homeopathy. In my view, it is an important issue in much of alternative medicine and quite possibly in conventional medicine as well. Over the years, several mechanisms have been put in place to prevent or at least minimize the problem, for instance, ethic committees and peer-review. The present study shows, I think, that these mechanisms are fragile and that, sometimes, they fail altogether.
In their article, the authors of the new homeopathic study suggest that more investigations of homeopathy for diabetic polyneuropathy should be done. However, I suggest almost precisely the opposite: unethical research of this nature should be prevented, and the existing mechanisms to achieve this aim must be strengthened.
Neck pain is a common problem which is often far from easy to treat. Numerous therapies are being promoted but few are supported by good evidence. Could yoga be the solution?
The aim of a brand-new RCT was to evaluate the effectiveness of Iyengar yoga for chronic non-specific neck pain. Patients were randomly assigned to either yoga or exercise. The yoga group attended a 9-week yoga course, while the exercise group received a self-care manual on home-based exercises for neck pain. The primary outcome measure was neck pain. Secondary outcome measures included functional disability, pain at motion, health-related quality of life, cervical range of motion, proprioceptive acuity, and pressure pain threshold. Fifty-one patients participated in the study: yoga (n = 25), exercise (n = 26). At the end of the treatment phase, patients in the yoga group reported significantly less neck pain compared as well as less disability and better mental quality of life compared with the exercise group. Range of motion and proprioceptive acuity were improved and the pressure pain threshold was elevated in the yoga group.
The authors draw the following conclusion: “Yoga was more effective in relieving chronic nonspecific neck pain than a home-based exercise program. Yoga reduced neck pain intensity and disability and improved health-related quality of life. Moreover, yoga seems to influence the functional status of neck muscles, as indicated by improvement of physiological measures of neck pain.”
I’d love to agree with the authors and would be more than delighted, if an effective treatment for neck pain had been identified. Yoga is fairly safe and inexpensive; it promotes a generally healthy life-style, and is attractive to many patients; it has thus the potential to help thousands of suffering individuals. However, I fear that things might not be quite as rosy as the authors of this trial seem to believe.
The principle of an RCT essentially is that two groups of patients receive two different therapies and that any difference in outcome after the treatment phase is attributable to the therapy in question. Unfortunately, this is not the case here. One does not need to be an expert in critical thinking to realise that, in the present study, the positive outcome might be unrelated to yoga. For instance, it could be that the unsupervised home exercises were carried out wrongly and thus made the neck pain worse. In this case, the difference between the two treatment groups might not have been caused by yoga at all. A second possibility is that the yoga-group benefited not from the yoga itself but from the attention given to these patients which the exercise-group did not have. A third explanation could be that the yoga teachers were very kind to their patients, and that the patients returned their kindness by pretending to have less symptoms or exaggerating their improvements. In my view the most likely cause of the results seen in this study is a complex mixture of all the options just mentioned.
This study thus teaches us two valuable lessons: 1) whenever possible, RCTs should be designed such that a clear attribution of cause and effect is possible, once the results are on the table; 2) if cause and effect cannot be clearly defined, it is unwise to draw conclusions that are definite and have the potential to mislead the public.
A stroke is a condition where brain cells get irreversibly damaged either by a haemorrhage in the brain or by a blood clot cutting off oxygen supply. This process leaves most patients with neurological deficits such as difficulties in moving, speaking, concentrating etc. As other parts of the brain learn to take over, these problems can partly or completely resolve themselves over time, but many patients are left with permanent handicaps. Stroke-rehabilitation can minimise these problems, and there is a long-standing debate as to which measures are most effective. Acupuncture has been discussed as a method to improve the results of stroke-rehabilitation, but the evidence is hotly disputed. This is why a new study in this area is an important contribution to our existing knowledge.
The aim of this randomised trial was to test the effectiveness of acupuncture in promoting the recovery of patients with ischaemic stroke and to determine whether the outcomes of combined physiotherapy and acupuncture are superior to those with physiotherapy alone. The Chinese investigators recruited 120 patients who received one of three daily treatments: 1) acupuncture, 2) physiotherapy, 3) physiotherapy combined with acupuncture. Motor function in the limbs was measured with the Fugl-Meyer assessment (FMA); the modified Barthel index (MBI) was used to rate activities of daily living; both of these measures are validated and well-established. All evaluations were performed by assessors blinded to treatment allocation.
At baseline, FMA and MBI scores did not significantly differ among the treatment groups. Compared with baseline, on day 28 of therapy, the mean FMA scores of the physiotherapy, acupuncture, and combined treatment groups had increased by 65.6%, 57.7%, and 67.2%, respectively; on day 56, FMA scores had increased by 88.1%, 64.5%, and 88.6%, respectively. The respective MBI scores in the three groups had increased by 85.2%, 60.4%, and 63.4% at day 28 and by 108.0%, 71.2%, and 86.2% at day 56, respectively. However, FMA scores did not significantly differ between the three treatment groups on the 28th day. By the day 56, the FMA and MBI scores of the physiotherapy group were 46.1% and 33.2% greater, respectively, than those in the acupuncture group. No significant differences were seen between the combined treatment group and the other groups. The FMA subscores for the upper extremities did not show significant improvements in any group on day 56.
The authors draw the following conclusion: “Acupuncture is less effective for the outcome measures studied than is physiotherapy. Moreover, the therapeutic effect of combining acupuncture with physiotherapy was not superior to that of physiotherapy alone. A larger-scale clinical trial is necessary to confirm these finding.”
Our own study arrived at similarly disappointing conclusions: “Acupuncture is not superior to sham treatment for recovery in activities of daily living and health-related quality of life after stroke, although there may be a limited effect on leg function in more severely affected patients“. Our review of all 10 sham-controlled RCTs in this area is also in line with the results of this new study: “Our meta-analyses of data from rigorous randomized sham-controlled trials did not show a positive effect of acupuncture as a treatment for functional recovery after stroke”
I am quite sure that some acupuncture-enthusiasts will dispute this evidence. They might argue that I am too critical, the trials were not done optimally, that acupuncturists have seen plenty of good results in their clinical practice, that acupuncture is a complex intervention that does not fit into the straight jacket of an RCT, that this or that “prestigious” organisation recommends acupuncture for stroke patients, that it would be wrong not to give acupuncture a try etc. etc. I would counter that the reliable evidence available to date is sufficiently conclusive to stop claiming that acupuncture is effective and thus give false hope to severely suffering, vulnerable patients. Moreover, I would advocate using the sparse available resources to help stroke victims with treatments that demonstrably work.
One of the best-selling supplements in the UK as well as several other countries is evening primrose oil (EPO). It is available via all sorts of outlets (even respectable pharmacies - or is that supposedly respectable?), and is being promoted for a wide range of conditions, including eczema. The NIH website is optimistic about its efficacy: “Evening primrose oil may have modest benefits for eczema.” Our brand-new Cochrane review was aimed at critically assessing the effects of oral EPO or borage oil (BO) on the symptoms of atopic eczema, and it casts considerable doubt on this somewhat uncritical view.
Here is what we did: We searched six databases as well as online trials registers and checked the bibliographies of included studies for further references to relevant trials. We corresponded with trial investigators and pharmaceutical companies to identify unpublished and ongoing trials. We also performed a separate search for adverse effects. All RCTs investigating oral intake of EPO or BO for eczema were included.
Two experts independently applied eligibility criteria, assessed risk of bias, and extracted data. We pooled dichotomous outcomes using risk ratios (RR), and continuous outcomes using the mean difference (MD). Where possible, we pooled study results using random-effects meta-analysis and tested statistical heterogeneity.
And here is what we found: 27 studies with a total of 1596 participants met our inclusion criteria: 19 studies tested EPO, and 8 studies assessed BO. A meta-analysis of results from 7 studies showed that EPO failed to improve global eczema symptoms as reported by participants and doctors. Treatment with BO also failed to improve global eczema symptoms. 67% of the studies had a low risk of bias for random sequence generation; 44%, for allocation concealment; 59%, for blinding; and 37%, for other biases.
Our conclusions were clear: Oral borage oil and evening primrose oil lack effect on eczema; improvement was similar to respective placebos used in trials. Oral BO and EPO are not effective treatments for eczema.
The very wide-spread notion that EPO is effective for eczema and a range of other conditions was originally promoted by the researcher turned entrepreneur, D F Horrobin, who claimed that several human diseases, including eczema, were due to a lack of fatty acid precursors and could thus be effectively treated with EPO. In the 1980s, Horrobin began to sell EPO supplements without having conclusively demonstrated their safety and efficacy; this led to confiscations and felony indictments in the US. As chief executive of Scotia Pharmaceuticals, Horrobin obtained licences for several EPO-preparations which later were withdrawn for lack of efficacy. Charges of mismanagement and fraud led to Horrobin being ousted as CEO by the board of the company. Later, Horrobin published a positive meta-analysis of EPO for eczema where he excluded the negative results of the largest published trial, but included results of 7 of his own unpublished studies. When scientists asked to examine the data, Horrobin’s legal team convinced the journal to refuse the request.
The evidence for EPO is negative not just for eczema. To the best of my knowledge, there is not a single disease or symptom for which it demonstrably works. Our own review of the data concluded ” EPO has not been established as an effective treatment for any condition”
Our new Cochrane review might help to put this long saga to rest. In my view, it is a fascinating tale of a scientist being blinded by creed and ambition. The results of such errors can be dramatic. Horrobin misled all of us: patients, health care professionals, scientists, regulators, decision makers, businessmen. This caused unnecessary expense and set back research efforts in a multitude of areas. I find the tale also fascinating from other perspectives; for instance, it begs the question why so many ‘respectable’ manufacturers and retailers are still allowed to make money on EPO. Is it not time to debunk the EPO-myth and say it as clearly as possible: EPO helps only those who financially profit from misleading the public?