The placebo response might be important in clinical practice, but it is certainly difficult to study and the findings of such investigations can be confusing. This seems to be exemplified by two new trials.
The first study examined the possibility of using theatrical performance tools, including stage directions and scripting, to reproducibly manipulate the style and content of a simulated doctor-patient encounter and influence the placebo response (defined as improvement of clinical outcome in individuals receiving inactive treatment) in experimental pain.
A total of 122 healthy volunteers were exposed to experimental pain using the cold pressor test and assessed for pain threshold and tolerance before and after receiving a placebo cream from a “doctor” impersonated by a trained actor. The actor alternated between two distinct scripts and stage directions. One script emulated a standard doctor-patient encounter (scenario A), while the other emphasized elements present in ritual healing such as attentiveness and strong suggestion (scenario B).
The placebo response size was calculated as the % difference in pain threshold and tolerance after exposure relative to baseline. Subjects demonstrating a ≥30% increase in pain threshold or tolerance relative to baseline were defined as responders. Each encounter was videotaped in its entirety.
Inspection of the videotapes confirmed the reproducibility and consistency of the distinct scenarios enacted by the “doctor”-performer. Furthermore, scenario B resulted in a significant increase in pain threshold relative to scenario A. This increase derived from the placebo responder subgroup; as shown by two-way analysis of variance (performance style, F = 4.30; p = 0.040; η(2) = 0.035; style × responder status interaction term, F = 5.21; p = 0.024) followed by post hoc analysis showing a ∼60% increase in pain threshold in responders exposed to scenario B (p = 0.020).
Performance style and response size in placebo responders and non-responders. Bars represent mean ± SE of % change in CPT threshold of 60 subjects in scenario A: 53 non-responders vs. 7 responders and 62 subjects in scenario B: 51 non-responders and 11 responders. Two-way ANOVA by performance style and responsiveness revealed significant effects of doctor’s performance (F = 4.30; p = 0.040; η2 = 0.035) and responsiveness (F = 134.71; p < 0.001) as well as a significant interaction term (F = 5.21; p = 0.024). ∗p = 0.020, Fisher’s least significant difference post hoc test.
The authors concluded that these results support the hypothesis that structured manipulation of physician’s verbal and non-verbal performance, designed to build rapport and increase faith in treatment, is feasible and may have a significant beneficial effect on the size of the response to placebo analgesia. They also demonstrate that subjects, who are not susceptible to placebo, are also not susceptible to performance style.
In the second study, the authors investigated if an implicit priming procedure, where participants were unaware of the intended priming influence, affected placebo analgesia.
In a double-blind experiment, healthy participants (n = 36) were randomized to different implicit priming types; one aimed at increasing positive expectations and one neutral control condition. First, pain calibration (thermal) and a credibility demonstration of the placebo analgesic device were performed. In a second step, an independent experimenter administered the priming task; Scrambled Sentence Test. Then, pain sensitivity was assessed while telling participants that the analgesic device was either turned on (placebo) or turned off (baseline). Pain responses were recorded on a 0-100 Numeric Response Scale.
Overall, there was a significant placebo effect (p < 0.001), however, the priming conditions (positive/neutral) did not lead to differences in placebo outcome. Prior experience of pain relief (during initial pain testing) correlated significantly with placebo analgesia (p < 0.001) and explained 34% of placebo variance. Trait neuroticism correlated positively with placebo analgesia (p < 0.05) and explained 21% of placebo variance.
The authors concluded that priming is one of many ways to influence behaviour, and non-conscious activation of positive expectations could theoretically affect placebo analgesia. Yet, we found no SST priming effect on placebo analgesia. Instead, our data point to the significance of prior experience of pain relief, trait neuroticism and social interaction with the treating clinician.
The two studies are similar but generate somewhat contradictory results. In the discussion section, the authors of the first paper stress that “replication of our findings in clinical populations; employing professional physicians of both sexes, are necessary in order to establish their generality and possible application in medical training, with the aim of improving patient outcome across diseases and treatment modalities.” This is certainly true. They continue by stating that “future studies using performance tools in clinical trial settings could demonstrate the potential of borrowing performance principles and techniques from traditional healing and applying them to physician–patient encounters in Western medicine, following certain necessary modifications. Performance tools could thus eventually be incorporated into the systematic training of physicians and medical students, possibly to complement programs in Narrative Medicine and Relational Medicine.”
These ideas are not dissimilar to what we have been discussing on this blog repeatedly. For instance, I have previously tried to explain that “the science and the art of medicine are essential elements of good medicine. In other words, if one is missing, medicine is by definition not optimal. In vast areas of alternative medicine, the science-element is woefully neglected or even totally absent. It follows, that these areas cannot be good medicine. In some areas of conventional medicine, the art-element is weak or neglected. It follows that, in these areas, medicine is not good either.”
The fact that the two studies above show contradictory findings is not easy to interpret. Possibly, this shows how fragile the placebo response can be. It can be influenced by a multitude of factors related to an experiment or the clinical setting. If that is so, and placebo effects are truly unreliable, it would be yet another argument for not relying on them in clinical routine. In my view, clinicians should try to maximize them where they can. Yet placebo effects are not normally a justification for employing placebo therapies in clinical practice. In other words, the fact that a bogus treatment can generate a placebo response is not a good reason for using it on patients who need help.
Good clinicians have probably always been good ‘performers’. Alternative practitioners tend to be excellent ‘performers’, and I am sure their success is mainly due to this ability. I see little reason why conventional practitioners should not (re-)learn the skills that once upon a time were called ‘good bed-side manners’. Maximizing the placebo effect in this way might maximize the benefit patients experience – and for that we do not require the placebo-therapies of alternative medicine.
Stable angina is a symptom of coronary heart disease which, in turn, is amongst the most frequent causes of death in developed countries. It is an alarm bell to any responsible clinician and requires causal, often life-saving treatments of which we today have several options. The last thing a patient needs in this condition is ACUPUNCTURE, I would say.
Yet acupuncture is precisely the therapy such patients might be tempted to employ.
Because irresponsible or criminally naïve acupuncturists advertise it!
Take this website, for instance; it informs us that a meta-analysis of eight clinical trials conducted between 2000 and 2014 demonstrates the efficacy of acupuncture for the treatment of stable angina. In all eight clinical trials, patients treated with acupuncture experienced a greater rate of angina relief than those in the control group treated with conventional drug therapies (90.1% vs 75.7%)….
I imagine that this sounds very convincing to patients and I fear that many might opt for acupuncture instead of potentially invasive/unpleasant but life-saving intervention. The original meta-analysis to which the above promotion referred to is equally optimistic. Here is its abstract:
Angina pectoris is a common symptom imperiling patients’ life quality. The aim of this study is to evaluate the efficacy and safety of acupuncture for stable angina pectoris. Clinical randomized-controlled trials (RCTs) comparing the efficacy of acupuncture to conventional drugs in patients with stable angina pectoris were searched using the following database of PubMed, Medline, Wanfang and CNKI. Overall odds ratio (ORs) and weighted mean difference (MD) with their 95% confidence intervals (CI) were calculated by using fixed- or random-effect models depending on the heterogeneity of the included trials. Total 8 RCTs, including 640 angina pectoris cases with 372 patients received acupuncture therapy and 268 patients received conventional drugs, were included. Overall, our result showed that acupuncture significantly increased the clinical curative effects in the relief of angina symptoms (OR=2.89, 95% CI=1.87-4.47, P<0.00001) and improved the electrocardiography (OR=1.83, 95% CI=1.23-2.71, P=0.003), indicating that acupuncture therapy was superior to conventional drugs. Although there was no significant difference in overall effective rate relating reduction of nitroglycerin between two groups (OR=2.13, 95% CI=0.90-5.07, P=0.09), a significant reduction on nitroglycerin consumption in acupuncture group was found (MD=-0.44, 95% CI=-0.64, -0.24, P<0.0001). Furthermore, the time to onset of angina relief was longer for acupuncture therapy than for traditional medicines (MD=2.44, 95% CI=1.64-3.24, P<0.00001, min). No adverse effects associated with acupuncture therapy were found. Acupuncture may be an effective therapy for stable angina pectoris. More clinical trials are needed to systematically assess the role of acupuncture in angina pectoris.
In the discussion section of the full paper, the authors explain that their analysis has several weaknesses:
Several limitations were presented in this meta-analysis. Firstly, conventional drugs in control group were different, this may bring some deviation. Secondly, for outcome of the time to onset of angina relief with acupuncture, only one trial included. Thirdly, the result of some outcomes presented in different expression method such as nitroglycerin consumption. Fourthly, acupuncture combined with traditional medicines or other factors may play a role in angina pectoris.
However, this does not deter them to conclude on a positive note:
In conclusion, we found that acupuncture therapy was superior to the conventional drugs in increasing the clinical curative effects of angina relief, improving the electrocardiography, and reducing the nitroglycerin consumption, indicating that acupuncture therapy may be effective and safe for treating stable angina pectoris. However, further clinical trials are needed to systematically and comprehensively evaluate acupuncture therapy in angina pectoris.
So, why do I find this irresponsibly and dangerously misleading?
Here a just a few reasons why this meta-analysis should not be trusted:
- There was no systematic attempt to evaluate the methodological rigor of the primary studies; any meta-analysis MUST include such an assessment, or else it is not worth the paper it was printed on.
- The primary studies all look extremely weak; this means they are likely to be false-positive.
- They often assessed not acupuncture alone but in combination with other treatments; consequently the findings cannot be attributed to acupuncture.
- All the primary studies originate from China; we have seen previously (see here and here) that Chinese acupuncture trials deliver nothing but positive results which means that their results cannot be trusted: they are false-positive.
My conclusion: the authors, editors and reviewers responsible for this article should be ashamed; they committed or allowed scientific misconduct, mislead the public and endangered patients’ lives.
Antrodia cinnamomea (AC) is a fungus which is used in Taiwan as a remedy for cancer, hypertension, hangover and other conditions. There are several commercial AC products and the annual market is worth over $100 million in Taiwan alone.
Several studies have suggested anti-cancer properties in vitro but few clinical trials have been reported. Now Taiwanese researchers published a double-blind, randomized clinical study to investigate whether AC had acceptable safety and efficacy in advanced cancer patients receiving chemotherapy.
Patients with advanced and/or metastatic adenocarcinoma, performance status (PS) 0-2, and adequate organ function who had previously been treated with standard chemotherapy were randomly assigned to receive routine chemotherapy regimens with AC (20 ml twice daily) orally for 30 days or placebo. The primary endpoint was 6-month overall survival (OS); the secondary endpoints were disease control rate (DCR), quality of life (QoL), adverse event (AE), and biochemical features within 30 days of treatment.
A total of 37 subjects with gastric, lung, liver, breast, and colorectal cancer (17 in the AC group, 20 in the placebo group) were enrolled in the study. Disease progression was the primary cause of death in 4 (33.3 %) AC and 8 (66.7 %) placebo recipients. Mean OSs were 5.4 months for the AC group and 5.0 months for the placebo group (p = 0.340), and the DCRs were 41.2 and 55 %, respectively (p = 0.33). Most hematologic, liver, or kidney functions did not differ significantly between the two groups, but platelet counts were lower in the AC group than in the placebo group (p = 0.02). QoL assessments were similar in the two groups, except that the AC group showed significant improvements in quality of sleep (p = 0.04).
The above figure shows the survival curves for both groups.
The authors concluded as follows: Although we found a lower mortality rate and longer mean OS in the AC group than in the control group, AC combined with chemotherapy was not shown to improve the outcome of advanced cancer patients, possibly due to the small sample size. In fact, the combination may present a potential risk of lowered platelet counts. Adequately powered clinical trials will be necessary to address this question.
I agree, the survival curve looks promising. But we must not get carried away: this was a tiny sample size and a relatively short treatment period. Thus the difference could be a coincidence or an artefact.
The investigators are sufficiently cautious in the interpretation of their findings, and most of us would probably agree that it is necessary to submit such traditional remedies to proper scientific tests. Yet, I feel a sense of unease when I read such articles.
On the one hand, it is possible that such investigations meaningfully contribute to progress. On the other hand, I wonder whether they merely end up providing a significant boost to the trade of bogus remedies sold at high prices to desperate patients. Do the benefits really out-weigh the risks? We will probably never know.
But to minimize the risk, the authors should now swiftly conduct a more definitive trial and create some clarity about the value or otherwise of this traditional cancer remedy.
A new study tested the efficacy of chiropractic spinal manipulative therapy (CSMT) for migraine. It was designed as a three-armed, single-blinded, placebo -controlled RCT of 17 months duration including 104 migraineurs with at least one migraine attack per month. Active treatment consisted of CSMT (group 1) and the placebo was a sham push manoeuvre of the lateral edge of the scapula and/or the gluteal region (group 2). The control group continued their usual pharmacological management (group 3).
The RCT began with a one-month run-in followed by three months intervention. The outcome measures were quantified at the end of the intervention and at 3, 6 and 12 months of follow-up. The primary end-point was the number of migraine days per month. Secondary end-points were migraine duration, migraine intensity and headache index, and medicine consumption.
The results show that migraine days were significantly reduced within all three groups from baseline to post-treatment (P < 0.001). The effect continued in the CSMT and placebo groups at all follow-up time points (groups 1 and 2), whereas the control group (group 3) returned to baseline. The reduction in migraine days was not significantly different between the groups. Migraine duration and headache index were reduced significantly more in the CSMT than in group 3 towards the end of follow-up. Adverse events were few, mild and transient. Blinding was strongly sustained throughout the RCT.
The authors concluded that it is possible to conduct a manual-therapy RCT with concealed placebo. The effect of CSMT observed in our study is probably due to a placebo response.
Chiropractors often cite clinical trials which suggest that CSMT might be effective. The effects sizes are rarely impressive, and it is tempting to suspect that the outcomes are mostly due to bias. Chiropractors, of course, deny such an explanation. Yet, to me, it seems fairly obvious: trials of CSMT are not blind, and therefore the expectation of the patient is likely to have major influence on the outcome.
Because of this phenomenon (and several others, of course), sceptics are usually unconvinced of the value of chiropractic. Chiropractors often respond by claiming that blind studies of physical intervention such as CSMT are not possible. This, however, is clearly not true; there have been several trials that employed sham treatments which adequately mimic CSMT. As these frequently fail to show what chiropractors had hoped, the methodology is intensely disliked by chiropractors.
The above study is yet another trial that adequately controls for patients’ expectation, and it shows that the apparent efficacy of CSMT disappears when this source of bias is properly accounted for. To me, such findings make a lot of sense, and I suspect that most, if not all the ‘positive’ studies of CSMT would turn out to be false positive, once such residual bias is eliminated.
This new study is amazing in several respects. It was conducted in Spain by otolaryngologists, and one of its authors is an employee of Boiron, the world’s biggest manufacturer of homeopathic products. It was designed as a double blind, placebo-controlled RCT. Patients aged 2 months to 12 years suffering from otitis media with effusion (OME), as diagnosed by pneumatic otoscopy (PNO) and tympanometry, were randomized into two groups. Both groups received aerosol therapy (mucolytics and corticosteroids). In addition, the experimental group received a homeopathic remedy of Agraphis nutans 5CH, Thuya Occidentalis 5CH, Kalium muriaticum 9CH and Arsenicum iodatum. The placebo group received placebos instead. Both of the treatments were continued for 3 months. Patients were evaluated by PNO examination and tympanometry at baseline, at 45 and 90 days.
A total of 97 patients were enrolled in this study. In the homeopathy group, 61.9% of individuals were cured according to PNO results by the 3rd visit compared with 56.8% of patients treated with placebo. 4.8% of patients in the homeopathy group suffered a recurrence (positive PNO in the 2nd visit changed to negative in the 3rd visit), while 11.4% did in the placebo group. These inter-group differences were not statistically significant. Adverse events were distributed similarly, except in the case of upper respiratory tract infections, which were less frequent in homeopathic group.
The authors of this new RCT concluded that the homeopathic scheme used as adjuvant treatment cannot be claimed to be an effective treatment in children with OME.
No surprises then – we already know that homeopathic remedies are placebos!
Sure, but at least two amazing features need to be pointed out:
- I am delighted that the authors did not try to spin the results such that they appear to be positive. Some investigators might have emphasised the fact that there was a (non-significant) trend in favour of homeopathy, and that, for a secondary outcome measure (upper respiratory infections), it even reached the level of statistical significance.
- Considering that this study was obviously Boiron-sponsored and its list of authors included an employee of this firm, such honesty can’t have been easy to maintain.
- The design of this RCT is also worth a mention: most alt med proponents seem to think that ‘adjunctive’ use of alt med needs to be tested via the infamous ‘A+B vs B’ design which fails to control for placebo effects and therefore invariably produces false positive findings. The authors of this trial did the right thing by randomising their patients into usual care + homeopathy vs usual care + placebo. This is very simple and has the advantage to actually provide a meaningful result.
In view of all this, I raise my hat to the Spanish researchers: very well done!!!
If all trials of homeopathy were conducted and reported in this honourable fashion, the collective evidence would be in a much better state and far less confusing.
In a recent PJ article, Michael Marshall from the ‘Good Thinking Society’ asked “WHY ON EARTH IS THE NHS SPENDING EVEN A SINGLE PENNY ON HOMEOPATHY?”. A jolly good question, given the overwhelmingly negative evidence, I thought – but one that must be uncomfortable to homeopaths. Sure enough, a proponent of homeopathy, Jeanette Lindsay from Glasgow, has objected to Marshall’s arguments in a short comment which is a fairly typical defence of homeopathy; I therefore take the liberty of reproducing it here (the 12 references in her text were added by me and refer to my footnotes below):
I wonder if people such as Michael Marshall (The Pharmaceutical Journal 2016;297:101), who would refuse  patients the option of NHS homeopathic treatment, have considered the plight of people failed by evidence-based medicine ?  Where are those with chronic, disabling conditions to turn when the medicines available on the NHS do not work, or worse, are positively harmful? 
Take the instance of a woman with multiple drug allergies who has no means of treating her severe inflammatory arthritis and no suitable analgesia.  It has been demonstrated that disease states with immune system involvement are particularly susceptible to the placebo effect but how does one induce this? Current thinking precludes treatment with placebo medicines but it so happens that homeopathic remedies would appear, from the results of clinical trials , to be a good substitute.  Used properly, there is a good chance that in this case homeopathic treatment may achieve a real therapeutic effect. 
Patients who cannot tolerate allopathic  treatment do not just go away because they cannot take the prescribed medicine.  They suffer and surely deserve a better range of options  than those provided by the current obsession with evidence-based medicine.  The availability of homeopathic treatment is important and should not be denied until better alternatives become commonplace.  Michael Marshall does not ‘refuse’ homeopathy on the NHS; that is not in his power. He merely questions whether NHS funds should not be spent on treatments that demonstrably do more good than harm.  I am sure he as carefully considered such patients.  Depending on the exact circumstances, such patients have many options: for instance, they could change their physician, have their diagnosis re-considered, or try a non-drug treatment.  An allergy to one drug is rarely (I would even say never) associated with allergies to all drugs for any given condition. Even if this were the case, there are several non-drug treatments for arthritis or other diseases.  I think this is fantasy; there is no good evidence from clinical trials to show that homeopathy is efficacious for either inflammatory or degenerative arthritis.  Is this an admission that homeopathic remedies are placebos?  I am not aware of sound evidence to support this statement.  ‘Allopathic’ is a derogatory term introduced by Hahnemann to defame conventional medicine.  I have never seen a patient who could not tolerate any prescription medicine. I suspect this is fantasy again.  Patients deserve the optimal therapy available for their conditions – that is a therapy that demonstrably generates more good than harm. Homeopathy is clearly not in this category.  An obsession? Yes, perhaps it is an obsession for some dedicated healthcare professionals to provide the best possible treatments for their patients. But the way it is put here, it sounds as though this was something despicable. I would argue that such an ‘obsession’ would be most commendable.  For practically all conditions, symptoms, illesses and diseases that afflict mankind, better alternatives than homeopathy have been available since about 150 years.
It seems to me that Jeanette Lindsay has been harshly disappointed by conventional medicine. Perhaps this is why, one day, she consulted a homeopath and received the empathy, understanding and compassion that she needed to get better. Many homeopaths excel at these qualities; and this is the main reason why their patients swear by them, even though their remedies are pure placebos.
My advice to such patients is: find a physician who has time, empathy and compassion. They do exist! Once you have found such a doctor, you can benefit from the compassion and empathy just as you may have benefitted from the homeopath’s compassion and empathy. But in addition to these benefits (and contrary to what you got from your homeopath), you will also be able to profit from the efficacy of the treatments prescribed.
To put it simply: homeopaths can help patients via non-specific therapeutic effects; responsible physicians can help patients via non-specific therapeutic effects plus the specific effects of the treatments they prescribe.
WARNING: THIS MIGHT MAKE YOU LAUGH OUT LOUDLY AND UNCONTROLLABLY.
Deepak Chopra rarely publishes in medical journals (I suppose, he has better things to do). I was therefore intrigued when I saw a recent article of which he is a co-author.
The ‘study‘ in question allegedly examined the effects of a comprehensive residential mind–body program on well-being. The authors describe it as “a quasi-randomized trial comparing the effects of participation in a 6-day Ayurvedic system of medicine-based comprehensive residential program with a 6-day residential vacation at the same retreat location.” They included 69 healthy women and men who received the Ayurvedic intervention addressing physical and emotional well-being through group meditation and yoga, massage, diet, adaptogenic herbs, lectures, and journaling. Key components of the program include physical cleansing through ingestion of herbs, fiber, and oils that support the body’s natural detoxification pathways and facilitate healthy elimination; two Ayurvedic meals daily (breakfast and lunch) that provide a light plant-based diet; daily Ayurvedic oil massage treatments; and heating treatments through the use of sauna and/or steam. The program includes lectures on Ayurvedic principles and lifestyle as well as lectures on meditation and yoga philosophy. The study group also participated in twice-daily group meditation and daily yoga and practiced breathing exercises (pranayama) as well as emotional expression through a process of journaling and emotional support. During the program, participants received a 1-hour integrative medical consultation with a physician and follow-up with an Ayurvedic health educator.
The control group simply had a vacation without any of the above therapies in the same resort. They were asked to do what they would normally do on a resort vacation with the additional following restrictions: they were asked not to engage in more exercise than they would in their normal lifestyle and to refrain from using La Costa Resort spa services. They were also asked not to drink ginger tea or take Gingko biloba during the 2 days before and during the study week.
Recruitment was via email announcements on the University of California San Diego faculty and staff and Chopra Center for Wellbeing list-servers. Study flyers stated that the week-long Self-Directed Biological Transformation Initiative (SBTI) study would be conducted at the Chopra Center for Wellbeing, located at the La Costa Resort in Carlsbad, California, in order to learn more about the psychosocial and physiologic effects of the 6-day Perfect Health (PH) Program compared with a 6-day stay at the La Costa Resort. The study participants were not blinded, and site investigators and study personnel knew to which group participants were assigned.
Participants in the Ayurvedic program showed significant and sustained increases in ratings of spirituality and gratitude compared with the vacation group, which showed no change. The Ayurvedic participants also showed increased ratings for self-compassion as well as less anxiety at the 1-month follow-up.
The authors arrived at the following conclusion: Findings suggest that a short-term intensive program providing holistic instruction and experience in mind–body healing practices can lead to significant and sustained increases in perceived well-being and that relaxation alone is not enough to improve certain aspects of well-being.
This ‘study’ had ethical approval from the University of California San Diego and was supported by the Fred Foundation, the MCJ Amelior Foundation, the National Philanthropic Trust, the Walton Family Foundation, and the Chopra Foundation. The paper’s first author is director of research at the Chopra Foundation. Deepak Chopra is the co-founder of The Chopra Center for Wellbeing.
Did I promise too much?
Isn’t this paper hilarious?
Just for the record, let me formulate a short conclusion that actually fits the data from this ‘study’: Lots of TLC, attention and empathy does make some people feel better.
This is hardly something one needs to write home about; and certainly nothing to do a study on!
But which journal would publish such unadulterated advertising?
On this blog, I have mentioned the JACM several times before. Recently, I wrote about the new man in charge of it. I concluded stating WATCH THIS SPACE.
I think the wait is now over – this paper is from the latest issue of the JACM, and I am sure we all agree that the new editor has just shown us of what he is made and where he wants to take his journal.
Just as I thought that this cannot get any better, it did! It did so in the form of a second paper which is evidently reporting from the same ‘study’. Here is its abstract unaltered in its full beauty:
The effects of integrative medicine practices such as meditation and Ayurveda on human physiology are not fully understood. The aim of this study was to identify altered metabolomic profiles following an Ayurveda-based intervention. In the experimental group, 65 healthy male and female subjects participated in a 6-day Panchakarma-based Ayurvedic intervention which included herbs, vegetarian diet, meditation, yoga, and massage. A set of 12 plasma phosphatidylcholines decreased (adjusted p < 0.01) post-intervention in the experimental (n = 65) compared to control group (n = 54) after Bonferroni correction for multiple testing; within these compounds, the phosphatidylcholine with the greatest decrease in abundance was PC ae C36:4 (delta = -0.34). Application of a 10% FDR revealed an additional 57 metabolites that were differentially abundant between groups. Pathway analysis suggests that the intervention results in changes in metabolites across many pathways such as phospholipid biosynthesis, choline metabolism, and lipoprotein metabolism. The observed plasma metabolomic alterations may reflect a Panchakarma-induced modulation of metabotypes. Panchakarma promoted statistically significant changes in plasma levels of phosphatidylcholines, sphingomyelins and others in just 6 days. Forthcoming studies that integrate metabolomics with genomic, microbiome and physiological parameters may facilitate a broader systems-level understanding and mechanistic insights into these integrative practices that are employed to promote health and well-being.
Now that I managed to stop laughing about the first paper, I am not just amused but also puzzled by the amount of contradictions the second article seems to cause. Were there 65 or 69 individuals in the experimental group? Was the study randomised, quasi-randomised or not randomised? All of these versions are implied at different parts of the articles. It turns out that they randomised some patients, while allocating others without randomisation – and this clearly means the study was NOT randomised. Was the aim of the study ‘to identify altered metabolomic profiles following an Ayurveda-based intervention’ or ‘to examine the effects of a comprehensive residential mind–body program on well-being’?
I am sure that others will find further contradictions and implausibilites, if they look hard enough.
The funniest inconsistency, in my opinion, is that Deepak Chopra does not even seem to be sure to which university department he belongs. Is it the ‘Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA.’ as indicated in the 1st paper or is it the ‘Department of Family and Preventive Medicine, University of California San Diego, La Jolla, California, USA’ as listed in the 2nd article?
Does he know from which planet he is?
After > 200 years of existence, homeopathy still remains unproven – in fact, most rational thinkers would call it disproven. Today only homeopaths doubt this statement; they work hard to find a water-tight proof that might show the doubters to be wrong.
What is better suited for this purpose than a few rigorous animal experiments?
Engystol® is a popular homeopathic product promoted as an anti-viral agent manufactured by Heel GmbH, Baden-Baden, Germany. In several in vivo and in vitro studies, it apparently affected an immune response. This new study was to “evaluate the innate and adaptive immuno-modulatory effects of oral Engystol® (1 or 10 tablets/L water consumed), prior to and post antigenic challenge in a mouse model with a well-characterized and clinically measureable immune system.”
The investigators first evaluated the murine immune response when oral Engystol® was given alone for 28 days. to mice. The animals were then challenged with an antigen-specific H5N1 HA vaccine while on Engystol® for an additional 33 days. Serum and supernatants from cultured splenic lymphocytes were collected and screened with a 32-cytokine panel. Serum vaccine epitope-specific IgG titers plus T cell and B cell phenotypes from splenic tissue were also evaluated.
The results showed that Engystol® alone did not alter immunity. However, upon vaccine challenge, Engystol® decreased CD4+/CD8+ ratios, altered select cytokines/chemokines, and anti-H5N1 HA IgG titers were increased in the group of mice receiving 10 tablet/L.
The authors concluded that “these data suggest that Engystol® can modulate immunity upon antigenic challenge.”
Engystol is being advertised as “a homeopathic preparation which has been scientifically proven to significantly reduce the duration and severity of symptoms during an acute viral infection and help protect from subsequent infections.” I was unable find good evidence for this claim and therefore have to assume that it is bogus. The only human trial I was able to locate was this one:
To compare the effects of a complex homeopathic preparation (Engystol; Heel GmbH, Baden-Baden, Germany) with those of conventional therapies with antihistamines, antitussives, and nonsteroidal antiinflammatory drugs on upper respiratory symptoms of the common cold in a setting closely related to everyday clinical practice.
Nonrandomized, observational study over a treatment period of maximally two weeks.
Eighty-five general and homeopathic practices in Germany.
Three hundred ninety-seven patients with upper respiratory symptoms of the common cold.
Engystol-based therapy or common over-the-counter treatments for the common cold. Patients receiving this homeopathic treatment were allowed other short-term medications, but long-term use of analgesics, antibiotics, and antiinflammatory agents was not permitted. Patients were allowed nonpharmacological therapies such as vitamins, thermotherapies, and others.
MAIN OUTCOME MEASURES:
The effects of treatment were evaluated on the variables fatigue, sensation of illness, chill/tremor, aching joints, overall severity of illness, sum of all clinical variables, temperature, and time to symptomatic improvement.
Both treatment regimens provided significant symptomatic relief, and this homeopathic treatment was noninferior in a noninferiority analysis. Significantly more patients (P < .05) using Engystol-based therapy reported improvement within 3 days (77.1% vs 61.7% for the control group). No adverse events were reported in any of the treatment groups.
This homeopathic treatment may be a useful component of an integrated symptomatic therapy for the common cold in patients and practitioners choosing an integrative approach to medical care.
Let me comment on the human study first. It is an excellent example of the bias that can be introduced by non-randomization. The patients in the homeopathic group obviously were those who chose to be treated homeopathically. Consequently they had high expectations in this therapy. Consequently they reported better results than the control group. In other words the reported outcomes have nothing to do with the homeopathic remedy.
But what about the animal study? Animals, we hear so often, do not exhibit a placebo response. Does that render this investigation any more reliable?
The answer, I am afraid is no.
The animal study in question had no control group at all. Therefore a myriad of factors could have caused the observed result. This study is very far from a poof of homeopathy!
But even if the findings of the two studies had not been the result of bias and confounding, I would be more than cautious about viewing them as anything near conclusive. The reason lies in the nature of this particular homeopathic remedy.
Engystol® contains Vincetoxicum hirundinaria (D6), Vincetoxicum hirundinaria (D10), Vincetoxicum hirundinaria (D30), sulphur (D4) and sulphur (D10). In other words, it is one of those combination remedies which are not sufficiently dilute to be devoid of active molecules. Sulphur D4, for instance, means that the remedy contains one part of sulphur in 10 000 parts of diluent. It is conceivable, even likely that such a concentration might affect certain immune parameters, I think.
And my conclusion from all this?
The proof of homeopathy – if it ever came – would need to be based on investigations that are more rigorous than these two rather pathetic studies.
The aim of a new meta-analysis was to estimate the clinical effectiveness and safety of acupuncture for amnestic mild cognitive impairment (AMCI), the transitional stage between the normal memory loss of aging and dementia. Randomised controlled trials (RCTs) of acupuncture versus medical treatment for AMCI were identified using six electronic databases.
Five RCTs involving a total of 568 subjects were included. The methodological quality of the RCTs was generally poor. Participants receiving acupuncture had better outcomes than those receiving nimodipine with greater clinical efficacy rates (odds ratio (OR) 1.78, 95% CI 1.19 to 2.65; p<0.01), mini-mental state examination (MMSE) scores (mean difference (MD) 0.99, 95% CI 0.71 to 1.28; p<0.01), and picture recognition score (MD 2.12, 95% CI 1.48 to 2.75; p<0.01). Acupuncture used in conjunction with nimodipine significantly improved MMSE scores (MD 1.09, 95% CI 0.29 to 1.89; p<0.01) compared to nimodipine alone. Three trials reported adverse events.
The authors concluded that acupuncture appears effective for AMCI when used as an alternative or adjunctive treatment; however, caution must be exercised given the low methodological quality of included trials. Further, more rigorously designed studies are needed.
Meta-analyses like this one are, in my view, perfect examples for the ‘rubbish in, rubbish out’ principle of systematic reviews. This may seem like an unfair statement, so let me justify it by explaining the shortfalls of this specific paper.
The authors try to tell us that their aim was “to estimate the clinical effectiveness and safety of acupuncture…” While it might be possible to estimate the effectiveness of a therapy by pooling the data of a few RCTs, it is never possible to estimate its safety on such a basis. To conduct an assessment of therapeutic safety, one would need sample sizes that go two or three dimensions beyond those of RCTs. Thus safety assessments are best done by evaluating the evidence from all the available evidence, including case-reports, epidemiological investigations and observational studies.
The authors tell us that “two studies did not report whether any adverse events or side effects had occurred in the experimental or control groups.” This is a common and serious flaw of many acupuncture trials, and another important reason why RCTs cannot be used for evaluating the risks of acupuncture. Too many such studies simply don’t mention adverse effects at all. If they are then submitted to systematic reviews, they must generate a false positive picture about the safety of acupuncture. The absence of adverse effects reporting is a serious breach of research ethics. In the realm of acupuncture, it is so common, that many reviewers do not even bother to discuss this violation of medical ethics as a major issue.
The authors conclude that acupuncture is more effective than nimodipine. This sounds impressive – unless you happen to know that nimodipine is not supported by good evidence either. A Cochrane review provided no convincing evidence that nimodipine is a useful treatment for the symptoms of dementia, either unclassified or according to the major subtypes – Alzheimer’s disease, vascular, or mixed Alzheimer’s and vascular dementia.
The authors also conclude that acupuncture used in conjunction with nimodipine is better than nimodipine alone. This too might sound impressive – unless you realise that all the RCTs in question failed to control for the effects of placebo and the added attention given to the patients. This means that the findings reported here are consistent with acupuncture itself being totally devoid of therapeutic effects.
The authors are quite open about the paucity of RCTs and their mostly dismal methodological quality. Yet they arrive at fairly definitive conclusions regarding the therapeutic value of acupuncture. This is, in my view, a serious mistake: on the basis of a few poorly designed and poorly reported RCTs, one should never arrive at even tentatively positive conclusion. Any decent journal would not have published such misleading phraseology, and it is noteworthy that the paper in question appeared in a journal that has a long history of being hopelessly biased in favour of acupuncture.
Any of the above-mentioned flaws could already be fatal, but I have kept the most serious one for last. All the 5 RCTs that were included in the analyses were conducted in China by Chinese researchers and published in Chinese journals. It has been shown repeatedly that such studies hardly ever report anything other than positive results; no matter what conditions is being investigated, acupuncture turns out to be effective in the hands of Chinese trialists. This means that the result of such a study is clear even before the first patient has been recruited. Little wonder then that virtually all reviews of such trials – and there are dozens of then – arrive at conclusions similar to those formulated in the paper before us.
As I already said: rubbish in, rubbish out!
What a silly question! At least this is what most sceptics would say: if we are not sure that it works, we do not need to spend any thoughts on a potential mechanism!
However, in the realm of acupuncture, the potential mode of action remains a hotly debated and fundamentally relevant issue.
The TCM folks, of course, ‘knew’ all along how acupuncture works: it re-balances the life-forces yin and yang. This is a nice theory – it has but one disadvantage: it has no bearing whatsoever on reality. Vitalistic ideas such as this one have long been proven to be nothing but fantasy.
Meanwhile, several more plausible hypotheses have been developed, and hundreds of papers have been published on the subject. One recent article, for instance, suggests a range of mechanisms including microinjury, increased local blood flow, facilitated healing, and analgesia. Acupuncture may trigger a somatic autonomic reflex, thereby affecting the gastric and cardiovascular functions. Acupuncture may also change the levels of neurotransmitters such as serotonin and dopamine, thereby affecting the emotional state and craving… By affecting other pain-modulating neurotransmitters such as met-enkephalin and substance P along the nociceptive pathway, acupuncture may relieve headache. Acupuncture may affect the hypothalamus pituitary axis and reduce the release of the luteinizing hormone…
Another article states that the Western explanation for acupuncture effectiveness is based upon more than half a century of basic and clinical research, which identified the activation of sensory system and the subsequent activity-dependent regulation of neurotransmitters, neurohormones, and several classes of neuromodulators as plausible mechanism for the acupuncture‘s therapeutic properties. The regulation of neurotrophins’ expression and activity is one of the possible neurophysiological mechanisms underlying acupuncture‘s effects on neuropathic pain, nerve injury, neurodegeneration, and even in the regulation of gonadal functions…
Recently Burnstock proposed that mechanical deformation of the skin by needles and application of heat or electrical current leads to release of large amounts of ATP from keratinocytes, fibroblasts and other cells in skin; the ATP then occupies specific receptor subtypes expressed on sensory nerve endings in the skin and tongue; the sensory nerves send impulses through ganglia to the spinal cord, the brain stem, hypothalamus and higher centres; the brain stem and hypothalamus contain neurons that control autonomic functions, including cardiovascular, gastrointestinal, respiratory, urinogenital and musculo-skeletal activity. Impulses generated in sensory fibres in the skin connect with interneurons to modulate (either inhibition or facilitation) the activities of the motoneurons in the brain stem and hypothalamus to change autonomic functions; specifically activated sensory nerves, via interneurons, also inhibit the neural pathways to the pain centres in the cortex.
A brand-new article in the journal SCIENTIFIC AMERICAN puts the hypothesis in perspective:
…scientists have been studying a roster of potential biological pathways by which needling might relieve pain. The most successful of these efforts has centered on adenosine, a chemical believed to ease pain by reducing inflammation. A 2010 mouse study found that acupuncture needles triggered a release of adenosine from the surrounding cells into the extracellular fluid that diminished the amount of pain the rodents experienced. The mice had been injected with a chemical that made them especially sensitive to heat and touch. The researchers reported a 24-fold increase in adenosine concentration in the blood of the animals after acupuncture, which corresponded to a two-thirds reduction in discomfort, as revealed by how quickly they recoiled from heat and touch. Injecting the mice with compounds similar to adenosine had the same effect as acupuncture needling. And injecting compounds that slowed the removal of adenosine from the body boosted the effects of acupuncture by making more adenosine available to the surrounding tissue for longer periods. Two years later a different group of researchers went on to show that an injection of PAP, an enzyme that breaks other compounds in the body down into adenosine, could relieve pain for an extended chunk of time by increasing the amount of adenosine in the surrounding tissue. They dubbed that experimental procedure “PAPupuncture.”
Both sets of findings have excited researchers—and for good reason. The current options for treating pain are limited and rely mostly on manipulating the body’s natural pain-management system, known as the opioid system. Opioid-based painkillers are problematic for several reasons. Not only does their efficacy tend to wane over time, but they have been linked to an epidemic of addiction and overdose deaths across the U.S.—so much so that the Centers for Disease Control and Prevention has recently advised doctors to seriously restrict their use. The available nonopioid pain treatments are few; many of them require multiple injections or catheterization to work; and they often come with side effects, such as impaired movement. Adenosine offers an entirely new mechanism to exploit for potential treatments—one that may come with fewer side effects and less potential for addiction. What is more, adenosine can be made to circulate in the body for prolonged stretches. Pharmaceutical companies are actively investigating adenosine-related compounds as potential drugs.
But however promising adenosine may be as a treatment, the findings from this research do not prove that acupuncture itself “works.” For one thing, the researchers did not show that the release of adenosine was specific to acupuncture. Acupuncture needles might cause adenosine to flood the surrounding tissue, but so might a hard pinch, or applied pressure, or any number of other physical insults. In fact, both of the studies found that when adenosine was turned on in mouse tissue by other mechanisms, the pain response was equal to or better than the response generated by acupuncture. For another thing, the study results offered no support for the use of acupuncture to treat any of the other conditions for which the procedure is often advertised. A localized adenosine response may mitigate localized pain. That does not mean it can also cure insomnia or infertility.
It may well be that the reams of research scientists have done on acupuncture have lit the path toward improved understanding of—and eventually better treatments for—intractable pain. But it may also be time to take whatever bread crumbs have been laid out by that work and move on.
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As we see, there is no shortage of potential explanations as to HOW acupuncture works. The most plausible theory still is that it works largely or even exclusively via a placebo effect.
Due to this type of mechanistic research, acupuncture has gained much credibility. The question is, does it deserve it? In my view, it would be much more fruitful to first make sure THAT acupuncture works (beyond a placebo response) and, if so, for what conditions. The question HOW it works is unquestionably interesting but in the final analysis it probably is secondary.