I have repeatedly stressed that herbal remedies can cause harm in a range of ways. Indian rheumatologists recently enforced this point by publishing a case-report of adrenal suppression caused by herbal remedies.
A 49-year-old male presented with polyarthritis from which he had suffered for more than 10 years. His serum cortisol levels were extremely low, he had vitamin D deficiency, and his rheumatoid factor was negative. He revealed symptoms of adrenal suppression, mainly muscle weakness and suicidal tendency, and few other psychiatric disturbances.
The patient eventually discontinued his herbal medicine. Then, he was put on deflazacort for 12 weeks at 12 mg twice daily and later the dose was tapered to 6 mg/day. Deflazocort, an intermediate-acting corticosteroid, was prescribed to minimize the probable withdrawal symptoms due to the probable presence of dexamethasone or betamethasone (long-acting steroids) presumably from the herbal medication.
The herbal samples of used by the patient was analysed by mass spectrometry. It showed the presence of steroidal compounds by the mass 393.81, which may be dexamethasone or betamethasone.
The authors of this paper believe that the symptoms of adrenal suppression could have precipitated or exacerbated the neuropsychiatric disturbances due to Hypothalamus-Pituitary-Adrenal (HPA) suppression. In their view, adrenal suppression following ingestion of herbal remedies is of major concern. Abrupt withdrawal of such products could precipitate adrenal failure which can be fatal.
It should be added, I think, that such illegal adulterations of herbal remedies have been reported with some regularity, particularly in Indian (and Chinese) preparations. Our systematic review showed that this problem has caused serious harm. The most severe documented adverse effects include agranulocytosis, meningitis, multi-organ failure, perinatal stroke, arsenic, lead or mercury poisoning, malignancies or carcinomas, hepatic encephalopathy, hepatorenal syndrome, nephrotoxicity, rhabdomyolysis, metabolic acidosis, renal or liver failure, cerebral edema, coma, intracerebral haemorrhage, and death.
As under-reporting can be suspected to be huge, we do currently not know how frequent these events are.
There are things that cannot be said too often. In medicine, these are often related to issues that can save lives. In alternative medicine, it is worth remembering that there is nothing that can save more lives than the following rule: EVEN AN APPARENTLY HARMLESS REMEDY WILL BECOME LIFE-THREATENING, IF IT IS USED AS AN ALTERNATIVE TO AN EFFECTIVE THERAPY FOR A SERIOUS CONDITION.
Here is a publication that serves as a very sad reminder of this important axiom.
Japanese physicians recently published a case-report of 2-year-old girl who died of precursor B-cell acute lymphoblastic leukaemia (ALL), the most common cancer in children. She had no remarkable medical history. She was transferred to a hospital because of respiratory distress and died 4 hours after arrival.
Two weeks before her death, she had developed a fever of 39°C, which subsided after the administration of a naturopathic herbal remedy. Subsequently, she developed jaundice one week before death, and her condition worsened on the day of death.
Laboratory test results on admission showed a markedly elevated white blood cell count. Accordingly, the cause of death was suspected to be acute leukaemia. Forensic autopsy revealed the cause of death to be precursor B-cell ALL.
With advancements in medical technology, the 5-year survival rate of children with ALL is nearly 90%. However, in this case, the deceased’s parents preferred alternative medicine to evidence-based medicine and had not taken her to a hospital for a medical check-up or immunisation since she was an infant. The authors state that, if she had received routine medical care, she would have a more than 60% chance of being alive 5 years after diagnosis. Therefore, we conclude that the parents should be accused of medical neglect regardless of their motives.
Alternative practitioners who treat their patients in this way, are in my experience often full of good intentions. They remind me of something Bert Brecht one wrote: THE OPPOSITE OF GOOD IS NOT EVIL, IT IS GOOD INTENTIONS.
A new study of homeopathic arnica suggests efficacy. How come?
Subjects scheduled for rhinoplasty surgery with nasal bone osteotomies by a single surgeon were prospectively randomized to receive either oral perioperative arnica or placebo in a double-blinded fashion. A commercially available preparation was used which contained 12 capsules: one 500 mg capsule with arnica 1M is given preoperatively on the morning of surgery and two more later that day after surgery. Thereafter, arnica was administered in the 12C potency three times daily for the next 3 days (“C” indicates a 100-fold serial dilution; and M, a 1000-fold dilution)
Ecchymosis was measured in digital “three-quarter”-view photographs at three postoperative time points. Each bruise was outlined with Adobe Photoshop and the extent was scaled to a standardized reference card. Cyan, magenta, yellow, black, and luminosity were analyzed in the bruised and control areas to calculate change in intensity.
Compared with 13 subjects receiving placebo, 9 taking arnica had 16.2%, 32.9%, and 20.4% less extent on postoperative days 2/3, 7, and 9/10, a statistically significant difference on day 7. Color change initially showed 13.1% increase in intensity with arnica, but 10.9% and 36.3% decreases on days 7 and 9/10, a statistically significant difference on day 9/10. One subject experienced mild itching and rash with the study drug that resolved during the study period.
The authors concluded that Arnica montana seems to accelerate postoperative healing, with quicker resolution of the extent and the intensity of ecchymosis after osteotomies in rhinoplasty surgery, which may dramatically affect patient satisfaction.
Why are the results positive? Pervious systematic reviews confirm that homeopathic arnica is a pure placebo. First, I thought the answer lies in the 1M potency. It could well still contain active molecules. But then I realised that the answer is much more simple: if we apply the conventional level of statistical significance, there are no statistically significant differences to placebo at all! I had not noticed the little sentence by the authors: a P value of 0.1 was set as a meaningful difference with statistical significance. In fact, none of the effects called significant by the authors pass the conventionally used probability level of 5%.
So, what so the results of this new study truly mean? In my view, they show what was known all along: HOMEOPATHIC REMEDIES ARE PLACEBOS.
Ayurvedic medicine has become highly popular in Western countries; it originates, of course, from India, and is considered to be one of the world’s oldest health care systems. Its adherents claim to create harmony between the body, mind, and spirit, maintaining that this balance prevents illness, treats acute conditions, and contributes to a long and healthy life. In India Ayurveda is mainstream and more than 90% of the population are said to use it. Outside India, Ayurveda is usually classified as an alternative therapy.
Ayurvedic treatments can consist of a range of modalities, including herbal remedies taken by mouth. These preparations have often been reported to be contaminated with toxic metals. Despite several case reports of poisoning from such contamination, the epidemiological evidence is still limited. A new paper on this important topic is therefore welcome. It reports on a cluster of lead and mercury toxicity cases which occurred 2011 among a community of users of Ayurvedic remedies in the US.
Following the identification of the index case, adherents of Ayurveda were offered heavy metals screening. The results showed that 46 of 115 participants (40%) had elevated blood lead levels (BLLs) of 10 μg/dl or above, with 9.6% of BLLs at or above 50 μg/dl.
The authors issued the following warning: this is the largest cluster of lead and mercury toxicity following use of Ayurvedic supplements described in the literature in the US. Contamination of herbal products is a public health issue of global significance. There are few regulations addressing contamination of “natural” products or supplements.
Rasa shastra, the practice of adding metals, minerals or gems to herbal preparations, is a well-documented part of Ayurveda. Adverse reactions to herbs are described in traditional Ayurvedic texts, but practitioners tend to be reluctant to admit that their remedies could be toxic and that reliable information on their risks is not readily available.
Already in 1990, a study on Ayurvedic medicines in India found that 41% of the products tested contained arsenic, and that 64% contained lead and mercury. A 2004 study found toxic levels of heavy metals in 20% of Ayurvedic preparations sold in the Boston area. A 2008 study of more than 230 products found that approximately 20% of remedies (and 40% of rasa shastra medicines) purchased over the Internet from U.S. and Indian suppliers contained lead, mercury or arsenic.
My 2002 systematic review summarised all the available evidence and concluded that heavy metals, particularly lead, have been a regular constituent of traditional Indian remedies. This has repeatedly caused serious harm to patients taking such remedies. The incidence of heavy metal contamination is not known, but one study shows that 64% of samples collected in India contained significant amounts of lead (64% mercury, 41% arsenic and 9% cadmium). These findings should alert us to the possibility of heavy metal content in traditional Indian remedies and motivate us to consider means of protecting consumers from such risks.
Despite these concerns, Ayurveda-fans continue to believe that the toxicity of these remedies is reduced through the purification processes of Ayurvedic remedy preparation. Bizarrely, they may involve prayers as well as physical pharmacy techniques.
The Indian government ruled that Ayurvedic products must be labelled with their metallic content. However, one Indian expert, has been quoted claiming that “the absence of post-market surveillance and the paucity of test laboratory facilities [in India] make the quality control of Ayurvedic medicines exceedingly difficult at this time”. In the US, most Ayurvedic products are marketed without having been approved by the FDA. Since 2007, the FDA has placed an import alert on some Ayurvedic products in order to prevent them from entering the US.
Protecting consumers from heavy metal poisoning by Ayurvedic remedies is certainly not easy – but, in the interest of public health, it is a task that we must tackle with some ungency.
One of the UK’s most ardent promoters of outright unproven and disproven therapies must be Dr Michael Dixon. He has repeatedly and deservedly received a mention on this blog. Steven Novella even called him once a ‘pyromaniac in a field of (integrative) straw men’. This is because Steven felt that Dixon uses phony arguments to promote dodgy therapies. If you find this hard to believe (after all Dixon is a GP who heads important organisations such as the NHS Alliance and the College of Medicine), just look at him dabbling in spiritual healing. Unusual, to say the least, I’d say. If you want to learn more about the strange Dr Dixon, you should read my memoir where he makes several remarkable appearances.
I always delight when I stumble over something that one of my former co-workers (yes, Dixon and I did collaborate for many years) has said to the press. This is why an otherwise silly article in the Daily Mail (yes, I know!) caught my attention; here is the relevant section: Dr Mike Dixon, a GP in Cullompton, Devon, and chairman of the College of Medicine, says he is a ‘fan’ of herbal medicines because they are ‘safe, help to encourage self-care by patients and, in cases such as mint and aloe vera, can be grown by the patients themselves, making them virtually free’.
As I already pointed out, Dixon does tend to promote bizarre concepts. The generalisation that herbal remedies are safe is not just bizarre, it also put the public at risk. One does not need to search long to find an article that makes this clear:
Various reports suggest a high contemporaneous prevalence of herb-drug use in both developed and developing countries. The World Health Organisation indicates that 80% of the Asian and African populations rely on traditional medicine as the primary method for their health care needs. Since time immemorial and despite the beneficial and traditional roles of herbs in different communities, the toxicity and herb-drug interactions that emanate from this practice have led to severe adverse effects and fatalities. As a result of the perception that herbal medicinal products have low risk, consumers usually disregard any association between their use and any adverse reactions hence leading to underreporting of adverse reactions. This is particularly common in developing countries and has led to a paucity of scientific data regarding the toxicity and interactions of locally used traditional herbal medicine. Other factors like general lack of compositional and toxicological information of herbs and poor quality of adverse reaction case reports present hurdles which are highly underestimated by the population in the developing world. This review paper addresses these toxicological challenges and calls for natural health product regulations as well as for protocols and guidance documents on safety and toxicity testing of herbal medicinal products.
Dixon once told me that GPs do not any longer read scientific papers. I think, however, that he should start doing so before the next time he misinform the public and endangers the health of vulnerable people.
The Telegraph today reports that, despite relentless lobbying from the Prince of Wales, UK herbalists will not, after all, be regulated by statute. Here are the most important statements from this article:
Prof David Walker, deputy chief medical officer, said he had taken the decision because there was insufficient evidence that the alternative therapy works, making it impossible to set standards of good practice. Three years ago ministers had pledged to bring in an official register of practitioners of herbal and Chinese medicines, which would see therapists regulated alongside other health workers, such as physiotherapists and speech therapists…But ministers blocked the proposals, instead setting up a new committee, led by the NHS deputy chief medical officer – which has now ruled against statutory regulation. The decision came despite lobbying from Prince Charles, a keen advocate of complementary medicines, and a supporter of regulation, who held a meeting with Jeremy Hunt in 2013 in which his concerns were raised…Prof Walker said that although most herbal practitioners were in favour of regulation, those opposed to it feared it would “confer an inappropriate level of legitimacy on herbal practice which was poorly supported by scientific evidence.” He said the decision to rule against regulation was “undoubtedly the most contentious area” addressed by the working party, which also looked at the safety of herbal medicine products. Instead, the report calls for a review of all ingredients sold in such medicines, to check their safety, with a “voluntary register” for practitioners who use them. It says there is too little evidence to show that herbal medicines improve health outcomes, making it “difficult to establish the boundaries of good practice” in regulating practitioners. It also says there is very little understanding of the risks posed to patients from current practices in herbal medicine…Prof Walker’s recommendation has triggered an immediate rift among the 26 members of his working party. Twelve members of the working party have written to Dr Dan Poulter, health minister, alleging that the decision will put the safety of the public at risk, because anyone will be able to promote themselves as an expert in herbal medicine, without any training. Research suggests around three million Britons a year consult herbal practitioners, operating in shops, online and in private clinics, with up to one in 12 of all adults using a herbal medicine at some stage. Michael McIntyre, chairman of the European Herbal and Traditional Medicine Practitioners Association, said the decision not to regulate practitioners could put the public at risk from rogue operators, with no training. The herbal practitioner, who was a member of the DoH working party, said: “We are deeply disappointed by this. We feared this issue was going to be kicked into the long grass, by quietly putting something out just before the election – and that is exactly what has happened.” He said the public needed the reassurance of statutory regulation, to know that any herbal doctor who is practising had received some training. The association disputed claims there was insufficient evidence to show that herbal medicines worked, saying that several trials had shown its impact for a number of conditions, but that the sector had less money than the pharmaceutical industry had to undertake mass research. The report says that although ministers promised “some form of regulation of herbal practitioners” this only committed the working party to consider the options, and that the introduction of regulation would require the sector to be “more science and evidence-based”.
Perhaps I should first state that I was not involved in any way in this process. Furthermore, I must say that I do think it is the right decision. To understand it better, I need to refer to several previous posts: yes, some herbal medicines are demonstrably effective. But the regulation in question is NOT about herbal medicines; it is about herbal practitioners, and the two are not necessarily related. UK herbal practitioners practice within a range of traditions including traditional European herbalism, TCM, or other schools of thought. They differ vastly but have one characteristic in common: they individualise their prescriptions according to the specific characteristics of the patient. Thus they would rarely prescribe the evidence-based herbal medicines but mix up prescriptions composed of several herbal ingredients. The problems with this approach are numerous:
- there is no good evidence that this approach of individualised herbalism is effective;
- the safety of the herbs used by traditional herbalists is often unknown;
- traditional herbalists tend to use obsolete diagnostic techniques, false-positive and false-negative diagnoses are thus inevitable;
- some of the herbal mixtures have been shown to be contaminated with toxic ingredients;
- some mixtures are adulterated with powerful prescription drugs;
- the herbal ingredients could interact with each other in an unpredictable manner;
- the herbal mixtures might interact with prescribed drugs.
The long and short of it is that nobody knows whether the treatments of traditional herbalists generate more good than harm. Regulating these professions by statute would merely give them a level of credibility that they do not deserve. As with the regulation of chiropractors or osteopaths in the UK, the regulation of herbalists would simply misled the public about the value of traditional herbalism, and it most likely would have prompted the herbalists to happily rest on their assumed merits claiming that their effectiveness and safety has been officially acknowledged and is therefore no longer in doubt.
In a nutshell: THE ‘PROPER’ REGULATION OF NONSENSE GENERATES PROPER NONSENSE
Chinese proprietary herbal medicines (CPHMs) are a well-established and a hugely profitable part of Traditional Chinese Medicine (TCM) with a long history in China and elsewhere; they are used for all sorts of conditions, not least for the treatment of common cold. Many CPHMs have been listed in the ‘China national essential drug list’ (CNEDL), the official reference published by the Chinese Ministry of Health. One would hope that such a document to be based on reliable evidence – but is it?
The aim of a recent review was to provide an assessment on the potential benefits and harms of CPHMs for common cold listed in the CNEDL.
The authors of this assessment were experts from the Chinese ‘Centre for Evidence-Based Medicine’ and one well-known researcher of alternative medicine from the UK. They searched CENTRAL, MEDLINE, EMBASE, SinoMed, CNKI, VIP, China Important Conference Papers Database, China Dissertation Database, and online clinical trial registry websites from their inception to 31 March 2013 for clinical studies of CPHMs listed in the CNEDL for common cold.
Of the 33 CPHMs listed in the 2012 CNEDL for the treatment of common cold, only 7 had any type of clinical trial evidence at all. A total of 6 randomised controlled trials (RCTs) and 7 case series (CSs) could be included in the assessments.
All these studies had been conducted in China and published in Chinese. All of them were burdened with poor study design and low methodological quality, and all had to be graded as being associated with a very high risk of bias.
The authors concluded that the use of CPHMs for common cold is not supported by robust evidence. Further rigorous well designed placebo-controlled, randomized trials are needed to substantiate the clinical claims made for CPHMs.
I should state that it is, in my view, most laudable that the authors draw such a relatively clear, negative conclusion. This does certainly not happen often with papers originating from China, and George Lewith, the UK collaborator in this article, is also not known for his critical attitude towards alternative medicine. But there are other, less encouraging issues here to mention.
In the discussion section of their paper, the authors mention that the CNEDL has been approved by the Chinese Ministry of Public Health and is currently regarded as the accepted reference point for the medicines used in China. They also explain that the CNEDL was officially launched and implemented in August 2009. The CNEDL is now up-dated every 3 years, and its 2012 edition contains 520 medicines, including 203 CPHMs. The CPHMs listed in CNEDL cover 137 herbal remedies for internal medicine, 11 for surgery, 20 for gynaecology, 7 for ophthalmology, 13 for otorhinolaryngology and 15 for orthopaedics and traumatology.
Moreover, the authors inform us that about 3,100 medical and clinical experts had been recruited to evaluate the safety, effectiveness and costs of CPHMs. The selection process of medicines into CNEDL was strictly in accordance with the principle that they ‘must be preventive and curative, safe and effective, affordable, easy to use, think highly of both Chinese and Western medicine’. A detailed procedure for evaluation is, however, not available because the files are confidential.
The authors finally state that their paper demonstrates that the selection of CPHMs into the CNEDL is less likely to be ‘evidence-based’ and revealed the sharp contrast between the policy and priority given to by the Chinese government to Traditional Chinese Medicine(TCM).
This surely must be a benign judgement, if there ever was one! I would say that the facts disclosed in this review show that TCM seems to exist in a strange universe where commercial interests are officially allowed to reign supreme over patients’ interests and public health.
Poor sleep quality during pregnancy is a frequent problem. Drug treatment can be problematic due to possible adverse effects for mother and embryo/foetus. Many pregnant women prefer natural treatments and assume that ‘natural’ equals harmless.
In the present study, the sedative effects of Bryophyllum pinnatum were investigated. This remedy is a phytotherapeutic medication predominantly used in anthroposophic medicine. In previous clinical studies on its tocolytic effect, B. pinnatum showed a promising risk/benefit ratio for mother and child. A recent analysis of the prescribing pattern for B. pinnatum in a network of anthroposophic physicians revealed sleep disorders as one of the most frequent diagnosis.
In this prospective, multi-centre, observational study, pregnant women suffering from sleep problems were treated with B. pinnatum (350mg tablets, 50% leaf press juice, Weleda AG, Arlesheim, dosage at physician’s consideration). Sleep quality, daily sleepiness and fatigue were assessed with the aid of standardised questionnaires, at the beginning of the treatment and after 2 weeks. Possible adverse effects perceived by the patients during the treatment were recorded.
The results show that the number of wake-ups, as well as the subjective quality of sleep was significantly improved at the end of the treatment with B. pinnatum. The Epworth Sleeping Scale decreased, indicating a reduction in tiredness during the day. There was, however, no evidence for a prolongation of the sleep duration, reduction in the time to fall asleep, as well as change in the Fatigue Severity Scale after B. pinnatum. No serious adverse drug reactions were detected.
From these data, the authors concluded that B. pinnatum is a suitable treatment of sleep problems in pregnancy. The data of this study encourage further clinical investigations on the use of B. pinnatum in sleep disorders.
Clinical trials of anthroposophic remedies, i.e. remedies which are based on the school of medicine founded by Rudolf Steiner, are very rare. Therefore this trial could be important.
B. pinnatum is a plant used in traditional Tai medicine against hypertension, and to some extend this makes sense: it contains cardiac glycosides which might help lowering elevated blood pressure. The reason for its use as a hypnotic, however, is not clear.
So, is B pinnatum really a ‘suitable treatment of sleep problems in pregnancy’? I doubt it for the following reasons:
- the effects documented in this study are far from convincing,
- we would need much more solid data to issue such a general recommendation,
- cardiac glycosides can cause very serious adverse effects,
- the sample size of the study is at least one dimension too small for assuming that it is safe,
- we know nothing about its potential to cause harm to the foetus.
Personally, I find it irresponsible to draw conclusions such as the ones above on the basis of data which are flimsy to the extreme. I ask myself, to what extend wishful thinking might be a regrettable characteristic for the entire field of anthroposophic medicine.
Dietary supplements (DS) are heavily promoted usually with the claim that they have stood the test of time and that they are natural and hence harmless. Unsurprisingly, their use has become very wide-spread. A new study determined the use of DSs, factors associated with DS use, and reasons for use among U.S. college students.
College students (N = 1248) at 5 U.S. universities were surveyed. Survey questions included descriptive demographics, types and frequency of DS used, reasons for use and money spent on supplements. Supplements were classified using standard criteria. Logistic regression analyses examined relationships between demographic and lifestyle factors and DS use.
Sixty-six percent of college students surveyed used DS at least once a week, and 12% consumed 5 or more supplements a week. Forty-two percent used multivitamins/multiminerals, 18% vitamin C, 17% protein/amino acids and 13% calcium at least once a week. Factors associated with supplement use included dietary patterns, exercise, and tobacco use. Students used supplements to promote general health (73%), provide more energy (29%), increase muscle strength (20%), and enhance performance (19%).
The authors of this survey concluded that college students appear more likely to use DS than the general population and many use multiple types of supplements weekly. Habits established at a young age persist throughout life. Therefore, longitudinal research should be conducted to determine whether patterns of DS use established early in adulthood are maintained throughout life. Adequate scientific justification for widespread use of DS in healthy, young populations is lacking.
Another new study investigated the use of DSs in 334 dancers from 53 countries, who completed a digitally based 35-question survey detailing demographic information and the use of DSs. Supplement use was prevalent amongst this international cohort, with 48% reporting regular DSs use. Major motives for supplement use were to improve health, boost immunity, and reduce fatigue. Forty-five percent believed that dancing increased the need for supplementation, whilst 30% recognized that there were risks associated with DSs.
The most frequently consumed DSs were vitamin C (60%), multivitamins (67%), and caffeine (72%). A smaller group of participants declared the use of whey protein (21%) or creatine (14%). Supplements were mainly obtained from pharmacies, supermarkets, and health-food stores. Dancers recognized their lack of knowledge in DSs use and relied on peer recommendations instead of sound evidence-based advice from acknowledged nutrition or health care professionals.
The authors concluded that this study demonstrates that DSs use is internationally prevalent amongst dancers. Continued efforts are warranted with regard to information dissemination.
Finally, a third study investigated use of DSs in patients in Japan. This survey was completed by 2732 people, including 599 admitted patients, 1154 ambulatory patients, and 979 healthy subjects who attended a seminar about DSs. At the time of the questionnaire, 20.4% of admitted patients, 39.1% of ambulatory patients, and 30.7% of healthy subjects were using DSs, which including vitamin/mineral supplements, herbal extracts, its ingredients, or food for specified health uses.
The primary purpose for use in all groups was health maintenance, whereas 3.7% of healthy subjects, 10.0% of ambulatory patients, and 13.2% of admitted patients used DSs to treat diseases. In addition, 17.7% of admitted patients and 36.8% of ambulatory patients were using DSs concomitantly with their medications. However, among both admitted patients and ambulatory patients, almost 70% did not mention DSs use to their physicians. Overall, 3.3% of all subjects realized adverse effects associated with DSs.
The authors concluded that communication between patients and physicians is important to avoid health problems associated with the use of DSs.
There is little doubt, DSs are popular with all sorts of populations and have grown into a multi billion dollar industry. There is also no doubt that the use of only very few DSs are evidence-based (and if so, in only relatively rare situations). And there can be no doubt that many DSs can do harm. What follows is simple: for the vast majority of DSs the benefits do not demonstrably out-weigh the risks.
If that is true, we have to ask ourselves: Why are they so popular?
The answer, I think, is because of the very phenomenon I am constantly trying to fight on this blog – IRRESPONSIBLE CHARLATANS PULLING WOOL OVER CONSUMERS EYES.
Guest post by Jan Oude-Aost
ADHD is a common disorder among children. There are evidence based pharmacological treatments, the best known being methylphenidate (MPH). MPH has kind of a bad reputation, but is effective and reasonably safe. The market is also full of alternative treatments, pharmacological and others, some of them under investigation, some unproven and many disproven. So I was not surprised to find a study about Ginkgo biloba as a treatment for ADHD. I was surprised, however, to find this study in the German Journal of Child and Adolescent Psychiatry and Psychotherapy, officially published by the “German Society of Child and Adolescent Psychiatry and Psychotherapy“ (Deutsche Gesellschaft für Kinder- und Jugendpsychiatrie und Psychotherapie). The journal’s guidelines state that studies should provide new scientific results.
The study is called “Ginkgo biloba Extract EGb 761® in Children with ADHD“. EGb 761® is the key ingredient in “Tebonin®“, a herbal drug made by “Dr. Wilma Schwabe GmbH“. The abstract states:
“One possible treatment, at least for cognitive problems, might be the administration of Ginkgo biloba, though evidence is rare.This study tests the clinical efficacy of a Ginkgo biloba special extract (EGb 761®) (…) in children with ADHD (…).“
“Eine erfolgversprechende, bislang kaum untersuchte Möglichkeit zur Behandlung kognitiver Aspekte ist die Gabe von Ginkgo biloba. Ziel der vorliegenden Studie war die Prüfung klinischer Wirksamkeit (…) von Ginkgo biloba-Extrakt Egb 761® bei Kindern mit ADHS.“ (Taken from the English and German abstracts.)
The study sample (20!) was recruited among children who “did not tolerate or were unwilling“ to take MPH. The unwilling part struck me as problematic. There is likely a strong selection bias towards parents who are unwilling to give their children MPH. I guess it is not the children who are unwilling to take MPH, but the parents who are unwilling to administer it. At least some of these parents might be biased against MPH and might already favor CAMmodalities.
The authors state three main problems with “herbal therapy“ that require more empirical evidence: First of all the question of adverse reactions, which they claim occur in about 1% of cases with “some CAMs“ (mind you, not “herbal therapy“). Secondly, the question of drug interactions and thirdly, the lack of information physicians have about the CAMs their patients use.
A large part of the study is based on results of an EEG-protocol, which I choose to ignore, because the clinical results are too weak to give the EEG findings any clinical relevance.
Before looking at the study itself, let’s look at what is known about Ginkgo biloba as a drug. Ginkgo is best known for its use in patients with dementia, cognitive impairment und tinnitus. A Cochrane review from 2009 concluded:
“There is no convincing evidence that Ginkgo biloba is efficacious for dementia and cognitive impairment“ .
The authors of the current Study cite Sarris et al. (2011), a systematic review of complementary treatment of ADHD. Sarris et al. mention Salehi et al. (2010) who tested Ginkgo against MPH. MPH turned out to be much more effective than Ginkgo, but Sarris et al. argue that the duration of treatment (6 weeks) might have been too short to see the full effects of Ginkgo.
Given the above information it is unclear why Ginkgo is judged a “possible“ treatment, properly translated from German even “promising”, and why the authors state that Ginkgo has been “barely studied“.
In an unblinded, uncontrolled study with a sample likely to be biased toward the tested intervention, anything other than a positive result would be odd. In the treatment of autism there are several examples of implausible treatments that worked as long as parents knew that their children were getting the treatment, but didn’t after proper blinding (e.g. secretin).
This study’s aim was to test clinical efficacy, but the conclusion begins with how well tolerated Ginkgo was. The efficacy is mentioned subsequently: “Following administration, interrelated improvements on behavioral ratings of ADHD symptoms (…) were detected (…).“ But the way they where “detected“ is interesting. The authors used an established questionnaire (FBB-HKS) to let parents rate their children. Only the parents. The children and their teachers where not given the FBB-HKS-questionnaires, inspite of this being standard clinical practice (and inspite of giving children questionnaires to determine changes in quality of life, which were not found).
None of the three problems that the authors describe as important (adverse reactions, drug interactions, lack of information) can be answered by this study. I am no expert in statistics but it seems unlikely to me to meaningfully determine adverse effects in just 20 patients especially when adverse effects occur at a rate of 1%. The authors claim they found an incidence rate of 0,004% in “700 observation days“. Well, if they say so.
The authors conclude:
“Taken together, the current study provides some preliminary evidence that Ginkgo biloba Egb 761® seems to be well tolerated in the short term and may be a clinically useful treatment for children with ADHD. Double-blind randomized trials are required to clarify the value of the presented data.“
Given the available information mentioned earlier, one could have started with that conclusion and conducted a double blind RCT in the first place!
The trends of this preliminary open study may suggest that Ginkgo biloba Egb 761® might be considered as a complementary or alternative medicine for treating children with ADHD.“
So, why do I care? If preliminary evidence “may suggest“ that something “might be considered“ as a treatment? Because I think that this study does not answer any important questions or give us any new or useful knowledge. Following the journal’s guidelines, it should therefore not have been published. I also think it is an example of bad science. Bad not just because of the lack of critical thinking. It also adds to the misinformation about possible ADHD treatments spreading through the internet. The study was published in September. In November I found a website citing the study and calling it “clinical proof“ when it is not. But child psychiatrists will have to explain that to many parents, instead of talking about their children’s health.
I somehow got the impression that this study was more about marketing than about science. I wonder if Schwabe will help finance the necessary double-blind randomized trial… See more at: http://summaries.cochrane.org/CD003120/DEMENTIA_there-is-no-convincing-evidence-that-ginkgo-biloba-is-efficacious-for-dementia-and-cognitive-impairment#sthash.oqKFrSCC.dpuf