Benefits and Risks of Neutering, an Evidence Update: Study Investigates Effects of Neutering in Golden Retreivers

Given that I recently presented a couple of evidence-updates on the subject the health effects of neutering, the timing was excellent for the release last week of a new research study looking at the same issue.

Torres de la Riva G, Hart BL, Farver TB, Oberbauer AM, Messam LLM, et al. (2013) Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers. PLoS ONE 8(2): e55937. doi:10.1371/journal.pone.0055937

This was a retrospective cohort study in which records were searched to identify Golden Retrievers who had been patients at the UC Davis veterinary school, were between 12 months and 8 years of age, and who could be classified as having been neutered “early” (before 12 months of age), “late” (after 12 months of age), or not at all. The occurrence of a number of diseases common in Golden Retrievers was then evaluated to see if it differed between dogs in these three categories. There are several reasons to be cautious in how we interpret the results of this study, but let’s start by looking at what those results were.

The authors looked at the occurrence of hip dysplasia (HD), elbow dysplasia (ED), cranial cruciate ligament rupture (CCL), and a number of cancers com including lymphosarcoma (LSA), hemangiosarcoma (HSA), mast cell tumor (MCT), osteosarcoma (OSA) and mammary cancer (MC). The figures below illustrate the relative occurrence of some of these diseases in males and females by neuter status (the diseases not shown did not occur often enough to be included in the analyses).

 ucdstudygoldensneuteringfig1

 

Figure 1. Percentages and number of cases over the total sample size for each neutering status group; intact and neutered early or late for male Golden Retrievers (1–8 years old) diagnosed with hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and/or mast cell tumor (MCT) at the Veterinary Medical Teaching Hospital of the University of California, Davis, from 2000–2009.

For HD and LSA, the differences between early-neutered and intact or late-neutered groups were statistically significant (K-M), as were differences for CCL between intact and early-neutered groups.

ucdstudygoldensneuteringfig2

 

Figure 2. Percentages and number of cases over the total sample size for each neutering status group; intact and neutered early or late for female Golden Retrievers (1–8 years old) diagnosed with hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and/or mast cell tumor (MCT) at the Veterinary Medical Teaching Hospital of the University of California, Davis, from 2000–2009.

For CCL the difference between intact and early-neutered was statistically significant (K-M). For HSA, the differences between early and late-neutered and intact and late-neutered groups were statistically significant (RR), as were differences for MCT between early and late-neutered groups. A similar statistical comparison for late neutering and intact groups was not possible for MCT because there were 0 cases in the intact group.

doi:10.1371/journal.pone.0055937.g002

These results suggest that there is a complex and inconsistent pattern of associations between neuter status and these diseases. In general, there was a tendency for neutered animals to have higher rates of these diseases than intact animals and for early neutered animals to have higher rates than late neutered animals. However, there are many cases in which differences were not statistically significant or the difference was significant in one sex but not the other, and a few in which the direction of the difference was opposite that expected (for example with HAS occurring more often in late-neutered females than either intact or early neutered females).

The difficulty lies in knowing what these results mean in terms of predicting the risks for individual pets and making decisions about neutering in general. The natural tendency will be to look at these data and conclude that not neutering, or neutering after 12 months of age, is safer than the common current practice of neutering most animals before 12 months. However, this is not a conclusion we can reliably draw from these data.

To begin with, this is a group of dogs that are, in many ways, very different from most dogs neutered by veterinarians. Apart from only representing one breed, and a breed known to have higher rates of the diseases studied than most other breeds, the subjects were patients at a university veterinary hospital. In general, only the sickest animals with the most unusual or serious diseases are seen at universities. Most healthy animals or those with typical illness are seen at general veterinary practices. So it is uncertain if neutering will have the same effects as in this study on dogs of other breeds or those healthy enough to have never seen the inside of a university hospital.

The population also contained small numbers of intact and “late” neutered dogs. This makes it more likely that small, random differences in the health of individual dogs in the study group could alter the apparent effects of neutering on health.  And the authors chose to limit the study population to dogs between 12 months and 8 years of age. Quite a few Golden Retrievers live past 8 years, and the rates of cancer generally go up dramatically with age. If the proportion of these diseases among intact and neutered animals over 8 years old are at all different from those in dogs under 8, then the direction and statistical significance of the differences between groups seen in this study could easily be altered.

And it’s important to consider the absolute risk and benefit numbers when making decisions about whether to neuter. If, in fact, neutering is strongly protective against a common cancer (as it is thought to be for mammary cancer) but also slightly increases the risk of a rare cancer, it may still make sense to neuter early depending on the unique situation of an individual patient.

Finally, two of the major diseases against which neutering is thought to be protective in females, uterine infection and mammary cancer, did not occur often enough to be included in the analysis. This may be because relatively few of the dogs were intact or because of the age cutoff. Obviously, if there really is a protective effect of neutering on these diseases that didn’t show up in this study, that might influence the interpretation of the results.

Overall, this is a useful piece of research adding to the information we have about the pros and cons of neutering and the possible role of age in the effect of neutering on disease. It should be over-interpreted as the final word by itself, but it should be incorporated into a broad analysis of all the available evidence.

As it stands, there is reason to believe early neutering has significant benefits in females, though as the recent systematic reviews pointed out the evidence behind this belief is not strong. There is also reason to be concerned about possible risks, though the evidence for this is also not robust yet. On balance, one can make a reasonable case on both sides, and the risk profile for individual dogs, as well as larger issues such as the problems associated with unwanted reproduction. Anyone who says there is an absolute and universal right answer concerning if and when to neuter female dogs is exaggerating by quite a bit.

For males, I believe the evidence of benefits from neutering, especially before 12 months of age, is not compelling, and I don’t see a strong reason to neuter earlier in the case of owned dogs with owners willing to commit to preventing roaming and unwanted reproduction and in the absence of intolerable interdog aggression. For large breeds in particular, delaying neutering of males seems reasonable, though we very much need better evidence to have confidence in such a recommendation. It is encouraging that more attention is now being paid to the complexities of neutering and the risks and benefits associated with it, and I am optimistic that this will lead us to more reliable guidelines in the future.

 

Posted in Science-Based Veterinary Medicine | 12 Comments

The Myth of Antioxidants?

I have written often about the popular notion that vitamins, dietary supplements, herbs, and other things which can be identified as “antioxidants” based on in vitro laboratory studies must automatically be good for our pets. This sort of simplistic reasoning is rarely justified in biology, and there is ample reason to doubt the hype that free radicals and oxidation are always bad and that antioxidants are always good.

In terms of specific supplements, there is large-scale clinical research evidence showing that even essential antioxidant vitamins, such as Vitamin E and Vitamin C, are not only not beneficial in excess but can increase the risk of cancer, heart disease, and other serious ailments and interfere with some medical treatments, such as chemotherapy. The common alternative medicine mantra that such supplements prevent cancer and other diseases, or help “boosting the immune system” in patients with serious illness, is inaccurate and potentially dangerous.

A recent review in Scientific American magazine does a nice job of summarizing the growing research evidence of the last decade showing that the theory of oxidative damage as a primary driver of aging and disease is deeply flawed, and that antioxidant supplements (as opposed to fruits and vegetables in their whole form) can often do more harm than good.

Moyer, M.W. The Myth of antioxidants: The hallowed notion that oxidative damage causes aging and that vitamins might preserve our youth is now in doubt. Scientific American. February, 2013. 64-67.

Though intended for the general public, and thus not a systematic review, this article does a good job of identifying several areas in which theories about the role of free radicals and antioxidant appears to have failed to hold up. The first is the notion that oxidative damage is a key component of aging and that reducing oxidation and supplementing antioxidant should lengthen life. The article cites a number of laboratory studies in invertebrates and mammals showing that animals genetically engineered to have reduced activity of natural antioxidant systems do, in fact, have increases in free radicals. However, these animals live longer than animals with better antioxidant function! And supplementing these subjects with antioxidants reduces their life expectancy to that of animals with normal anti-oxidative functions.

The author also reviews some of the early studies produced by the first proponents of the oxidative damage theory, and points out that attempts to replicate these have usually failed. There are even studies showing that application of an herbicide which increases free radical production can increase lifespan in some laboratory species, and again antioxidant supplementation eliminates this increase in life expectancy.

More nuanced theories suggest that, as is usually the case, the truth is complex and depends on context and many factors. There are undoubtedly situations in which free radicals and oxidative damage are harmful. But there may also be situations in which increases in free radicals may be beneficial. Such oxidative compounds increase as a consequence of exercise, for example, and antioxidant vitamins appear in some research to attenuate the benefits of exercise. And oxidative damage is one mechanism by which the immune system and some medicines destroy infectious organisms and cancer cells. Antioxidant that interfere with these beneficial activities can actually cause harm.

There is much work yet to be done to refine our understanding of the positive and negative effects of oxidation and antioxidants, but one thing is clear. Simplistic notions of antioxidant supplements as automatically beneficial are nonsense and not a sound basis on which to recommend supplements, herbal remedies, or other preventative or therapeutic products.

Posted in Herbs and Supplements, Science-Based Veterinary Medicine | 10 Comments

Benefits and Risks of Neutering, an Evidence Update: Neutering and Mammary Cancer in Female Dogs

This is another in my series of evidence updates on the risks and benefits of neutering in dogs and cats. I will be updating the evidence and conclusions of my original 2010 review based on a series of systematic reviews being produced by a research group in the UK. The first such update concerned the effect of neutering and age at neutering on urinary incontinence in female dogs. This update concerns one of the most important reasons to considering neutering female dogs: mammary cancer.

Beauvais W, Cardwell JM, Brodbelt DC. The effect of neutering on the risk of mammary tumours in dogs–a systematic review.J Small Anim Pract. 2012 Jun;53(6):314-22.

In my 2010 review, I found evidence suggesting that mammary cancer is very common in intact female dogs, that it is malignant about half the time, and that neutering dramatically reduces the risk of this disease. I also found evidence suggesting that neutering is most effective in preventing mammary cancer if performed before the first heat, and that the benefit disappears after the third estrus cycle. This is a major reason why I still recommend neutering young female dogs.

The UK group found only 4 research reports that addressed the question of the impact of neutering on mammary cancer risk and that met the minimum quality criteria for review. One of these also addressed the issue of whether age at neutering was associated with mammary cancer risk. They reported the following results: 

  1. All studies had significant methodological flaws, and none provided information that could be confidently generalized to the general dog population.
  2. One study found a strong protective effect of neutering. Another found some protective effects but these were inconsistent. The remaining two studies found no association between neutering and mammary cancer risk.
  3. The one study that evaluate age at neutering found a significant decrease in the protective benefits of neutering with each of the first three heats, and no benefit after the third heat.

Once again, the general conclusions are consistent with the current consensus, that neutering young female dogs likely has a meaningful beneficial effect on reducing the risk of mammary cancer later in life. However, the existing evidence is extremely weak, and this conclusion has to be viewed as tentative. While current evidence does not justify a change in the common practice of recommending neutering to prevent mammary cancer, we cannot view our current conclusion with any great confidence, and we desperately need more and better quality research to determine if the current evidence is correct or if a significant change in our recommendations is called for.

As always, the decision to neuter must be based on the entirety of the known risks and benefits, with a clear understanding of the uncertainty involved, as well as on the unique circumstances of each individual. The value of this review is not so much in answering our questions about the subject, which it cannot do, but in making it clear what the strengths and weaknesses are in the evidence behind our current recommendations and in guiding us in the development of better evidence that will permit more confident conclusions.

 

 

Posted in Science-Based Veterinary Medicine | 11 Comments

Benefits and Risks of Neutering, an Evidence Update: Neutering and Urinary Incontinence in Female Dogs

A couple of years ago, I wrote a review of the risks and benefits of neutering. This handout, originally intended for clients, was also turned into a journal article for veterinarians:

Evaluating the benefits and risks of neutering dogs and cats CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources 2010 5, No. 045

This was a narrative review, not a systematic review. This means that I found as many research reports as possible related to the subject and informally evaluated their conclusions. I did not conduct a formal appraisal of the level and quality of the research evidence according to predetermined and standardized criteria, as would be done in a systematic review.

There are pros and cons to each format. A narrative review is more likely to reach pragmatic conclusions based on the existing evidence, whereas a systematic review is more likely to end with no useful conclusion if the quality of the evidence examined is less that perfect, which it almost always is. However, a systematic review is likely to be more thorough and provides a better picture of how strong the existing evidence is so that it is possible to gauge how much confidence we ought to have in the conclusions we base on it.

As a practicing clinician, I need to make practical decisions even when the evidence isn’t perfect, so a narrative review was more suited to my goals. However, as a strong supporter of the practice of evidence-based veterinary medicine, I believe systematic reviews and a clear understanding of the limitations of the available evidence on specific subjects is critical to making fully informed decisions. So I am thrilled to see that a research group in the U.K. has begun producing a series of systematic reviews of the evidence concerning the risks and benefits of neutering in dogs. I intend to evaluate these reviews as they appear to help update and appraise the evidence on this important subject and provide a bit of context for veterinarians and pet owners trying to make practical decisions about neutering. The first subject reviewed was the potential effect of neutering on the risk of urinary incontinence.

Beauvais W, Cardwell JM, Brodbelt DC.The effect of neutering on the risk of urinary incontinence in bitches – a systematic review.J Small Anim Pract. 2012 Apr;53(4):198-204.

In my 2010 narrative review, I was only able to report research suggesting urinary incontinence was common in spayed female dogs and that the research was conflicting on whether incontinence was more common in dogs spayed at younger ages. I did not identify specific research comparing the occurrence of incontinence in intact and spayed females.

The UK group identified only one research study evaluating the relative risk of incontinence in neutered and intact dogs, and three studies evaluating the effect of age at neutering on incontinence risk. The authors concluded the following:

1. All the evidence was weak, with a significant risk of error

2. The one study that evaluated risk of incontinence with neutering found that neutering significantly increased the risk of incontinence.

3. Two of the three studies found no association between age at neutering and incontinence and one found that incontinence was more likely the younger dogs were when neutered.

So the conclusions are consistent with the current consensus, that neutering female dogs does increase the risk of urinary incontinence and that age at neutering probably does not affect this risk significantly. There is, of course, significant uncertainty because the evidence is quite weak. That does not mean, however, we cannot reach a conclusion or make recommendations. If this were the case, we would almost never be able to decide anything in medicine since the evidence is often imperfect. It simply means that we have to acknowledge the uncertainty and recognize that our conclusions are provisional and might need to change as new evidence emerges.

Any decision about neutering should not, of course, be based solely on this single issue. Urinary incontinence, while inconvenient, is a relatively minor and highly treatable clinical problem. And there are a large number of other risks, benefits, and personal considerations involved in making a decision about neutering. The important thing is that we make informed decisions and that we understand the strengths and weaknesses in the available evidence. The reviews produced by this group will be invaluable in facilitating this.

Posted in Science-Based Veterinary Medicine | 1 Comment

Measuring Arthritis Pain in Dogs: Are Owner Surveys as Good as Force Plate Analysis?

I have written about a wide variety of conventional and alternative therapies for arthritis pain in dogs. A recurring issue in evaluating these therapies is how we know whether or not interventions designed to reduce pain in animals are effective. While I do not think dogs have beliefs or expectations about their treatment, and so do not experience the kind of direct placebo effect people can, they can manifest differences in both the objective features of their illness and in the symptoms they exhibit when given placebo therapies, due to a variety of effects others have described (e.g. classical conditioning, human interaction, etc.).  The indirect placebo effect of a therapy on the vets and owners involved in studying a pain control treatment for dogs are well-documented, and these frequently lead us to believe such therapies are effective when they aren’t. So finding a reliable, repeatable, and accurate measure of the effect of a pain medication is critical.

The gold standard for testing arthritis medications in dogs is force plate analysis. This tool involves having a dog walk across a plate that records the amount of weight carried on each limb. As pain is decreased with treatment, lameness improves and the amount of weight the dog can carry on the affected limb increases. This is a technically challenging tool, but the most accurate and objective way we have of knowing if we have successfully diminished pain in a dog’s limb.

A subjective measure of some kind is often used in arthritis treatment studies instead of force plate analysis because such tools are easier and less expensive to use. With proper blinding and controls, subjective evaluations by owners and veterinarians can have some value in measuring response to pain treatment. However, the results of such evaluations are often inconsistent, and the risk of uncontrolled placebo effects is high.

A new study has attempted to validate a subjective owner rating tool by comparing the results of this survey to force plate analysis in dogs with newly diagnosed arthritis given a NSAID or a placebo.

Brown DC, Boston RC, Farrar JT.
Comparison of force plate gait analysis and owner assessment of pain using the canine brief pain inventory in dogs with osteoarthritis. J Vet Intern Med. 2013 Jan;27(1):22-30.

The dogs in this study were assessed by force plate gait analysis the first day, and the owners completed a previous validated questionnaire about pain and the degree to which it interfered with their pets’ activities. The dogs were then randomly assigned to either a placebo or NSAID treatment and re-assessed in 2 weeks.

As expected, the dogs on NSAID therapy showed a significantly greater increase in the weight placed on their arthritic limbs than those placed on the placebo. This objectively showed that the medication improved their lameness, and presumably their pain. The two measures of effect in the client questionnaire also showed significant improvement in dogs on NSAID compared to dogs taking placebo. This would seem to show that the questionnaire also accurately identified the improvement in pain on the medication..

However, the authors also found that there was no correlation or concordance between the survey measures and the force plate analysis. In other words, while overall the survey scores changed in the expected way, the survey scores and force plate analysis measurements for individual dogs didn’t seem to be related or to change together.

What does this mean? Well, the authors argue that both the survey and force plate analysis are measuring real improvements in pain, but the force plate specifically measures the change in lameness associated with treating pain while owners are measuring more general signs of comfort and normal activity at home. This is certainly a plausible explanation, but it doesn’t entirely make sense.

If the drug reduces pain, and pain is causing the lameness, then as pain decreases the lameness should decrease. The force plate results show that this is what is happening. However, if the surveys are also measuring accurately the reduction in pain, even if they are not measuring lameness, then the decrease in pain and the improvement in lameness should occur together and the two measures should correlate.

Think of it this way. Let’s say we want to measure the effect of a drug in reducing nausea and vomiting. If we count the number of episodes of vomiting, and the drug clearly reduces how often a person throws up, then that is an objective, though indirect, measure of nausea (analogous to force late analysis evaluating pain by measuring lameness). And if we ask people about their nausea, and if they say they are less nauseated when taking the drug, that is another way to measure nausea and the effect of the drug (analogous to asking clients about their dogs’ pain). But if both tests are measuring the same thing, then the results should correlate. People who say they feel less nauseated should vomit less than people who say they don’t feel any better.

But what happens if we give the drug and on average the group reports they feel less nauseated and overall they vomit less, but the individual responses on the survey don’t match the frequency of vomiting? People who say the feel better might or might not vomit less. And people might show less vomiting even when they say they don’t feel any less nauseated. Are the survey and the frequency of vomiting both measuring nausea? And which is more important? Do we primarily want people to report feeling better but still vomit just as much, in which case the survey might an appropriate tool? Or is it more important to reduce the amount of vomiting even if some people who vomit less say they don’t feel better?

In the case of arthritis pain in dogs, it is difficult to picture a situation in which reducing the signs of pain perceptible by the owner is more important than reducing the lameness caused by the pain. This raises the question not only of what the owner survey is actually measuring but also the question of when would it be an appropriate tool to use to measure the efficacy of an analgesic therapy. If animal owners report their pets have less pain but we don’t have an objective measure such as force plate analysis, it seems likely that the intervention is changing something about the dogs’ behavior which the owners are detecting, but it isn’t clear that something is pain.

Posted in Science-Based Veterinary Medicine | 4 Comments

Repeat After Me: “Dogs are not Wolves”

It should be obvious that there is a difference between acknowledging domestic dogs evolved from wolves (which is a widely accepted theory with strong supporting evidence) and saying that dogs essentially are wolves (which is nonsense). Try to picture a pack of pugs or Bichon Frise brining down and savaging an elk, and the impact of artificial selection ought to be quite clear.

Unfortunately, people all too often misconstrue the ancestry of dogs as a justification for extrapolating from what they know (or think they know) about wolves and applying that knowledge to our canine companions. The infamous “alpha roll,” is an example of this. Attempting to establish a healthy, smoothly functioning relationship with your dog by periodically tackling and pinning him or her to the ground, preferably while growling ferociously, is a ludicrous idea that nevertheless managed to gain some popularity at one time on the basis of the argument (grossly oversimplified) that that is how wolves establish stable dominance relationships.

The most prevalent form of this kind of phylogenic fallacy today are some of the canine dietary fads, including raw meat-based or BARF diets, grain-free diets, and so-called “biologically appropriate” feeding. I’ve written about BARF diets, and the fallacious reasoning behind then, before. And I have written numerous times about raw diets and all the reasons why the have no proven benefits and at least some undeniable risks (for example). While the statement that the dietary needs of dogs may be similar to those of wolves in some ways, based on their phylogenetic relationship, is perfectly reasonable, the claim that one can accurately predict the optimal diet for dogs based on what wolves eat in the wild is simply nonsense. The dietary needs of dogs have been shaped by many factors, not least among them their long association with humans, and they need to be worked out through thorough and rigorous scientific research, not speculation and the appeal to nature fallacy.

An example of the kind of research that we need, which also shows in specific and relevant ways that dogs are not wolves, is a recent study reported in the journal Nature:

Erik Axelsson,Abhirami Ratnakumar,Maja-Louise Arendt, Matthew T. Webster,Michele Perloski,Olof Liberg,Jon M. Arnemo,Kerstin Lindblad-Toh.. The genomic signature of dog domestication reveals adaption t a starch rich diet. Published online January 23, 2013. doi:10.1038/nature11837

The study consisted of a thorough comparison of dog and wolf genomes, identifying a number of differences related to the domestication process. Many of these differences have to do with genes involved in brain development and function, which will hopefully help us to better understand the behavioral differences between dogs and wolves related to domestication. But a significant subset of the genes found to be different between dogs and wolves involve the digestion of starch. Starch was an important energy source for humans at the time of the domestication of the dog, and so dogs adapted to the available food in ways that distinguish them from their more carnivorous ancestors.

Our results show that adaptations that allowed the early ancestors of modern dogs to thrive on a diet rich in starch, relative to the carnivorous diet of wolves, constituted a crucial step in early dog domestication…The results presented here demonstrate a striking case of parallel evolution whereby the benefits of coping with an increasingly starch-rich diet during the agricultural revolution caused similar adaptive responses in dog and human.

This genetic information, and the already well-known anatomic differences between dogs and wolves, make it clear that domestication has dramatically altered the structure and function of the dog body. Extrapolating from the natural diet of wolves to the nutritional needs of dogs is not reasonable nor supported by the data, which instead indicates that dogs are more suited to an omnivorous diet. The current fad that identifies carbohydrates in general, and grains in particular, as inappropriate and harmful for dogs is irrational and contrary to the clear evidence that dogs are well-adapted to such food sources.

Posted in Nutrition | 35 Comments

New Review of Complemetary and Alternative Therapies for Arthritis

I’ve written extensively about alternative arthritis therapies, largely because that is one of the most common conditions for which complementary and alternative treatments are used. While a few are promising (such as fish oils), there is little good evidence to support most such practices. A detailed and very useful new review of alternative therapies for arthritis in humans has just been released. And while extrapolation from humans to pets has dangers and has to be viewed with some skepticism, this at least gives us some guidance as to whether such therapies have proven their value for people, a question for which the evidence is usually much greater in quantity and quality than we often get for veterinary uses.

The review, produced by the non-profit group Arthritis Research UK, is divided into two reports:

Complementary and alternative medicines for the treatment of rheumatoid arthritis, osteoarthritis and fibromyalgia

Practitioner-based complementary and alternative therapies for the treatment of rheumatoid arthritis, osteoarthritis, fibromyalgia and low back pain

I won’t go through all the findings, but in terms of the therapies I’ve covered before, the review pretty much confirms the evidence to date, with a couple of exceptions.

Glucosamine
The review assigns a score of 2/4 for glucosamine sulphate, which is defined as:

There’s only a little evidence to suggest the compound might work. The evidence in this category often comes from a single study which has reported positive results, and there are therefore important doubts about whether or not it works.

The evidence for glucosamine hydrochloride is not even as strong as this.

My own assessment is slightly more pessimistic that this based largely on these two findings:

There’s some evidence that more recent trials and those using higher?quality methods are less likely to show a benefit.Trials that used the best methods to make sure that participants didn’t know which treatment they were getting didn’t show significant benefits in pain relief and improved physical function.

So while there is some positive clinical trial evidence the better the controls for bias and error, the less likely positive results will be found, which is usually a signs that the therapy is not actually effective.

No significant risks appeared in the trials evaluated.

Chondroitin
This supplement, like glucosamine, is assigned a score of 2/4, indicating claims of a meaningful benefit are dubious.

Overall, evidence from trials with a good study design in allocating participants to treatment groups and trials that used the most appropriate statistical methods had lower estimates of effectiveness of chondroitin, particularly in terms of reduction in joint pain.In the most recent review, the authors concluded that chondroitin (or its combination with glucosamine) didn’t reduce joint pain to any clinically meaningful extent or change clinical aspects of the joint.

Chondroitin appears to have no significant risks.

Fish Oil
The evidence is limited, but it is pretty strong for a benefit of fish liver oil in treatment of rheumatoid arthritis. However, the evidence is not sufficient to determine if there is benefit from the more common fish body oil for non-rheumatoid osteoarthritis.

There’s good evidence that fish body oil can result in improvement in the symptoms of rheumatoid arthritis and some unconfirmed evidence that the combined treatment of fish body and liver oils might also be of long-term benefit, particularly in reducing daily NSAID use. Evidence for the use of fish liver oil for osteoarthritis is based on insufficient data.

Side effects appear to be mild, though high-dose or prolonged use of fish liver oil can lead to serious overdoses of Vitamin A.

Homeopathy
Despite the fact that there is no plausible reason to believe homeopathy could be an effective therapy for anything, this review took the slightly naïve approach of review the clinical trial research without regard to prior plausibility. Nevertheless, the score for arthritis was a 1/5 for both osteoarthritis and rheumatoid arthritis:

Overall, there’s no evidence to suggest that the compound works or only a little evidence which is outweighed by much stronger evidence that it doesn’t work.

The score for fibromyalgia was a 2/5, and detailed discussion of some of this research can be found here and here.

SAMe
The review only found a couple of studies looking at use of SAMe for osteoarthritis, but it found them to be consistently positive and of reasonable quality, earning a score of 4/5.

There’s some consistency to the evidence, which will come from more than one study, to suggest that the compound works. Although there are still doubts from the evidence that it works, on balance we feel that it’s more likely to be effective than not.Evidence from RCTs suggests that SAMe is effective in reducing functional limitations and, to a lesser extent, pain in osteoarthritis.

Generally, SAMe is believed to be safe, but severe side effects (mania and anxiety) have been seen in some individuals with depression.

Acupuncture
The report was very favorable for a positive effect of acupuncture on osteoarthritis. However, the authors based their conclusion mostly on a 2010 Cochrane Review which found < 5% difference in pain scores between real and fake acupuncture:

Pain after 8 weeks:-People who had acupuncture rated their pain to be improved by about 4 points on a scale of 0 to 20. -People who received sham acupuncture rated their pain to be improved by about 3 points on a scale of 0 to 20.-People who received acupuncture had a 1 point greater improvement on a scale of 0-20. (5% absolute improvement).Pain after 26 weeks:-People who had acupuncture rated their pain to be improved by slightly more than 3 points on a scale of 0 to 20. -People who received sham acupuncture rated their pain to be improved by slightly less than 3 points on a scale of 0 to 20.-People who received acupuncture had under a 1 point greater improvement on a scale of 0-20. (2% absolute improvement). Physical function after 8 weeks :-People who had acupuncture rated their function to be improved by about 11 points on a scale of 0 to 68. -People who received sham acupuncture rated their function to be improved by about 8 points on a scale of 0 to 68.-People who received acupuncture had about a 3 point greater improvement on a scale of 0-68. (4% absolute improvement) Physical function after 26 weeks :-People who had acupuncture rated their function to be improved by about 11 points on a scale of 0 to 68. -People who received sham acupuncture rated their function to be improved by about 10 points on a scale of 0 to 68.-People who received acupuncture had about a 1 point greater improvement on a scale of 0-68. (2% absolute improvement)

Not very compelling results. And the other studies the authors reviewed included one large trial, which showed no benefit, and 7 very small trials, two of admittedly poor quality, which showed small but inconsistent benefits. Given this evidence, the score seems excessively positive. And given the concern about significant placebo effects involved in acupuncture therapy, even if this tiny difference is real, it is unlikely to be of real benefit to veterinary patients but very likely to be subject to the caregiver placebo effect.

Chiropractic
Only 1 trial was identified, which was not well controlled, so this intervention received a score of 2/5, indicating no compelling evidence of effectiveness. And unlike most of the therapies reviewed, chiropractic received only an intermediate “amber” grade for safety:

Therapies with an amber rating have commonly reported side-effects (even if they’re mainly minor symptoms) or more serious side-effects.

 

 

 

Posted in General | 37 Comments

Response to Comments from the American Holistic Veterinary Medical Association on the AVMA Homeopathy Resolution

Detailed evidence supporting the AVMA resolution on homeopathy is available in The Case Against Homeopathy, and the Academy of Veterinary Homeopathy’s attempted counter arguments are examined in detail in The Evidence for Homeopathy-A Close Look. What is presented here is a response to a more abbreviated commentary on The Case Against Homeopathy produced by the American Holistic Veterinary Medical Association (AHVMA).

Comments on Resolution 3-2013 Homeopathy, from Connecticut
Nancy Scanlan, DVM, Executive Director
American Holistic Veterinary Medical Association

While the AVMA has models, such as their model practice act, the actual practice of veterinary medicine is a legal matter for state veterinary boards. The AVMA model practice act (AVMA2012) and a number of state practice acts include homeopathy specifically, as a reflection of this. The AAVSB comments on its model practice act definition of the practice of veterinary medicine: “The definition in Section 104 [Practice of Veterinary Medicine] is purposely broad in order to provide substantial latitude to the Board in the adoption and implementation of rules.” (AAVSB 2009)

This is irrelevant. The resolution has no binding legal force and specifically states that “veterinarians may legally employ any therapy that complies with the applicable laws and regulations governing the practice of veterinary medicine.” The fact that some state governments have recognized homeopathy as part of the practice of veterinary medicine has no bearing on whether or not it is an effective therapy. Just as there is political pressure from a passionate minority on the AVMA to reject Resolution 3, so similar pressure has been applied to other organizations to ignore the science showing homeopathy doesn’t work.

AHVMA maintains that one must include an expert in any discussion of a treatment modality, whether it be those taught in the core curriculum of veterinary schools or those taught as electives or special training outside of the core courses. Experts are those who use the modality in practice, and who are invited by practitioners of CAVM to lecture and write about its use. No one person can be an expert in all things, and so the person’s expertise should be specific to the subject being discussed. This resolution should be sent to a task force with representatives from both sides of the argument to in order to create a balanced document for delegates to base their decision upon. As a beginning, this document is accompanied by a White Paper supported by the Academy of Veterinary Homeopathy, which presents the rest of the evidence not present in the paper accompanying the Connecticut resolution.

This essentially says that only homeopaths are qualified to evaluate the validity of homeopathy.

However, homeopathy is not a recognized medical specialty in veterinary or human medicine, and the expertise homeopaths claim is self-determined. If a committee of believers in homeopathy is formed to evaluate the scientific evidence for homeopathy, the outcome is a forgone conclusion.

Homeopaths have a vested interest in declaring their own practice to be legitimate. The delegates and other veterinarians who may choose to evaluate the scientific literature concerning homeopathy have no “horse in the race,” as it were. If homeopathy were effective, conventional veterinarians would simply adopt it and offer it to their patients like any other therapy. This has not happened in the two centuries since the invention of homeopathy because a compelling scientific case for the theories and practices of homeopathy has not been made. It is not necessary that the delegates, or rest of the profession, rely on homeopaths to interpret the scientific evidence concerning homeopathy for us.

And finally, the White Paper in support of this resolution contains numerous misstatements and so cannot be used reliably to judge the resolution. It only addresses one part of homeopathic practices and by and large ignores others (such as less highly diluted remedies, different methods of diagnosis, etc.) that do not fit the items it is addressing. It ignores hundreds of legitimate research papers. And it relies in part on the 275 page House of Commons Science and Technology Committee (HOC Committee) report on Homeopathy (HOC Committee 2010), which may have been accepted physically by the Chief Scientific Advisor to the British government. However it was  NOT accepted by the British government. Part of the reasoning for not accepting the report was:

“our  continued position on the use of homeopathy within the NHS is that the local NHS and clinicians, rather than Whitehall, are best placed to make decisions on what treatment is appropriate for their patients -including complementary or alternative treatments such as homeopathy -and provide accordingly for those treatments.”  (Secretary of State for Health 2010) This is an essentially political question, and again the resolution does not in any way prohibit veterinarians from choosing to employ homeopathy. It expresses the opinion of the AVMA that the scientific evidence does not support homeopathy to be effective. This is the same conclusion reached by the House of Commons Science and Technology Committee and the science-based medical professions in general. It is up to politicians and courts to decide what implications the scientific consensus has for government health insurance and other matters of public policy, but that again has no bearing on the assessment of the scientific evidence concerning homeopathy.

The HOC Committee is a Parliamentary committee consisting of elected officials (laymen), similar to our House and Senate Committees. Like our congressional committees, the attitudes of the members of the committee influence the choice of witnesses called, the evidence accepted, weight given to evidence, and final conclusions. The HOC committee stated “It is not necessary for Scientific evidence to be absolutely uniform in order to establish that a practice is ineffective or unsafe.” One might say the same for establishing that a practice is effective or safe.

The citation of the HOC committee was simply to illustrate that bodies with far greater resources than the AVMA House of Delegates have investigated this matter and drawn a clear conclusion about the state of the science. The Case Against Hoemompathy does not rely on the HOC findings but evaluates the scientific evidence itself and merely uses the HOC hearings to help illustrate points that are rooted in this evidence.

Few of those called as witnesses by the HOC committee were practicing homeopaths: in the Memorandum submitted by David Tredinnick MP, Chairman, Parliamentary Group for Integrated and Complementary Healthcare , he stated:“ Only one doctor using homeopathy gave oral evidence, and none are scheduled for Monday. No doctors using homeopathy in a primary care setting have been asked. Dr David Reilly from the Glasgow Homeopathic Hospital is regarded as a leading expert on this subject and should have been called. In addition, the Society of Homeopaths, which was discussed both directly and indirectly as the principal organisation representing non-medical homeopaths, should have had the opportunity to put its views forward. I believe that the Committee should have ensured that all the experts in this field were given the opportunity to give oral evidence.”

The HOC did give homeopaths an opportunity to send a representative to present their position, but it did not defer to their expertise because only the homeopathic profession recognizes this as legitimate.

The White Paper accompanying this response from the AHVMA addresses the specific concerns about homeopathic theory and homeopathic research that are raised in the Connecticut White Paper. The following is a critique of the sections of the Connecticut White Paper which contain misleading statements:

Page 1 “There is no consistent body of in vitro or animal model research evidence  showing the presence of any biologically active factor in homeopathic remedies or a meaningful biological effect of homeopathic treatment beyond placebo. 

(Homeopathic remedies come in 4 groups of dilutions: X, C, L, and M. The X and C dilutions not only have demonstrable factors, some can be tasted. Dilutions made by compounding pharmacies of drugs used for cats and small dogs are in the X range. This includes items such as Humulin U-100 diluted to 10 U/ml, or interferon eyedrops diluted to 30 U/ml. Any veterinarian who uses Interferon as an oral medication and dilutes it as recommended has created a dilution that is the same concentration as a 6X dilution.)

It is disingenuous to suggest that homeopathy is not primarily concerned with the use of ultradilute remedies that do not contain measurable active ingredients. Insulin diluted to 10U/mL is not a homeopathic remedy; it is simply off-label use of a pharmaceutical. And herbal preparations which contain pharmacologically active ingredients are part of herbal medicine, not homeopathy.

According to the Academy of Veternary Homeopathy, “ A homeopathic remedy is a single substance derived from a plant, animal or mineral. This is then subjected to a special procedure called potentization….Dr. Hahnemann discovered that the effect of homeopathic medicines is strengthened dramatically upon successive dilutions and vigorous shaking between each dilution. The final dilution can be very high…These substances are specially prepared so that they have no toxic “side effects”…Homeopathy is a safe form of treatment in that there are no chemicals or drugs in the remedies so there are no side effects.” By their own definition, a homeopathic remedy no longer contains any chemicals from the original substance used.

Furthermore, the AVH specifically discourages the use of remedies containing conventional pharmaceuticals or herbal ingredients: “Drugs, herbs and other forms of treatment prevent cure and cause ultimate harm to the patient. Hahnemann states that only the medicine homeopathic to the patient’s condition is to be used in treatment…Drugs and methods of treatment which are not homeopathic to the case are to be avoided because of the possibility of interference with the progress of cure.”

Even the AVH white paper states, “medicines used in homeopathy are often administered in highly diluted form…their mode of action differs from substances given in pharmacologic doses and having direct agent-dependent actions on the body.” The document then goes to great lengths to defend the theory that ultradilute substances can have biologic effects, and all but a few of the papers cited relate to the investigation of ultradilute homeopathic remedies. Ultradilute remedies make up the vast majority of homeopathic treatment, and if these are ineffective (as the evidence clearly shows they are), then homeopathy is no more than a placebo therapy.

“While some apparently positive studies exist, published almost exclusively in journals dedicated to the promotion of homeopathy and other alternative therapies”

I have a 65 page list of references to published homeopathic articles, which includes the following journals in just the first 6 pages:

Immunology Today
Exp Biol Med
Comptes-Rendus de l’Académie des Sciences de Paris
Journal of Allergy and Clinical Immunology
Inflamm.Res.
Micron.
Nature
European Journal of Pharmacology
Biophys
Annals of the New York Academy of Sciences
Immunol Invest.

“some apparently positive trials exist, but these are of low -quality and highly subject to bias. Systematic reviews of the clinical trial literature consistently find no evidence of an effect beyond placebo” 

An implication that journals such as Immunology Today, Exp Biol Med, Journal of Allergy and Clinical Immunology, Annals of the New York Academy of Sciences, etc. publish inferior work

The level of evidence within the hierarchy of evidence-based medicine, and the quality of controls for chance, bias, confounding, and other errors, are determined by specific established criteria, including study design, sample size, randomization, blinding, control groups, and many others. The level and quality of a study, and the reliability of the results, is determined by these features, not by the journal in which the report is published. Even highly respected journals can publish results that are clearly false. A paper by Andrew Wakefield suggesting a relationship between vaccination and autism was published in the Lancet in 1998, and it was retracted in 2010 and Dr. Wakefield stripped of his license for the fraudulent and unethical study. The journal Nature published a paper reporting an effect of a homeopathic preparation on basophil degranulation in 1988, and then published a followup title “’High-dilution’ experiments a delusion” showing the results to be due to inadequate blinding. Even high-quality journals can, and often do, publish poor quality research. And the evidence in such journals cited by homeopaths in the AVH white paper did not even approach a compelling case for the efficacy of hoemopathy, as can be seen in The Evidence for Homeopathy-A Close Look, in which I review these citations in detail.

There is ample evidence for a publication bias in homeopathy journals and other journals devoted to alternative medicine. In 1995, only 1% of studies published in alternative medicine journals reported negative results, and in 2001 95% of such studies reported positive results (Schmidt, K., Pittler, M.H., Ernst, E., (2001a) A profile of journals of complementary and alternative medicine Swiss Med Weekly Vol. 131 pp. 588-591; Schmidt, K., Pittler, M.H., Ernst, E., (2001b) Bias in alternative medicine is still rife but is diminishing British Medical Journal Vol. 323 no. 7320 p. 1071)

A study published in 2005 (in an alternative medicine journal) found that 69% of homeopathy studies in mainstream journals reported negative results whereas only 30% of studies in alternative journals reported a negative result. (Caulfield, T., and DeBow, S., 2005 A systematic review of how homeopathy is represented in conventional and CAM peer reviewed journals BMC Complementary and Alternative Medicine Vol. 5 no. 12) 

Of the 16 veterinary studies listed in the CVMA white paper that reported positive results, 11 were published in journals dedicated to homeopathy or alternative medicine. Of the 15 veterinary studies listed in the CVMA white paper that reported negative results, only 2 were published in such alternative journals.

And while some positive studies have been reported in mainstream journals, it is still true that the vast majority are found in dedicated journals with a clear bias. And the systematic reviews cited in the CVMA white paper also demonstrate clearly that the higher level and quality and the better control for bias in a study, the less likely the results are to be positive, consistent with homeopathy being a placebo therapy. Only when low-level and low-quality studies are given equal weight (as in the Swiss homeopathy report) can one manufacture the appearance of strong research support for an effect above placebo.

Also on page 2: the first of several citations from the 2010 report from the House of Commons Science and Technology Committee, which was notaccepted by the British government

The conclusions were accepted by the Scientific Advisor to the government, but for political reasons (including pressure from the Royal Family, who are believers in homeopathy, the official policy of the government has not yet moved into alignment with the position of the scientific and medical communities that the NHS should not offer an ineffective therapy. However, two of the five homeopathic hospitals funded under the NHS (Liverpool and Tunbridge Wells) have closed in the last year, as well as numerous other facilitieg offering homeopathy in the UK. The politics are catching up to the science.

Page 7, item II G cites the AAVSB’s stance that “CE programs that advocate unscientific modalities of diagnosis or therapy are not eligible for RACE approval,” implying that they never approve CE on homeopathy. On page 14 item IIA states that “Since 2009, the Registry for Approved Continuing Education (RACE) has denied approval for continuing education offerings involving the teaching of homeopathy.” RACE approved the following 3 lectures on homeopathy at the 2009 AHVMA annual conference:

Pointers to Case Taking andCase Organization

Some Methods for Handling and Understanding Complex Cases

Dealing with the End Stage and Hospice Patient

All 3 were presented by Larry Bernstein, VMD, who uses homeopathy extensively in his practice, as well as teaching and lecturing regularly on the subject.

In 2011, the AVH sued the American Association of Veterinary State Boards because its RACE committee had begun denying approval for homeopathy CE course which had previously been approved despite not meeting the requirements for RACE approval, which sate:

[approved courses must] build upon or refresh the participant in the standards for practice and the foundational, evidence-based material presented in accredited colleges or schools of veterinary medicine or accredited veterinary technician programs…CE programs that advocate unscientific modalities of diagnosis or therapy are not eligible for RACE approval…All scientific information referred to, reported or used in RACE Program Applications in support or justification of an animal-care recommendation must conform to the medically accepted and scientifically supported standards of experimental design, data collection and analysis.

The AHVMA went so far as to set up an alternative CE approval organization, Registry of Alternative and Integrative Veterinary Medical Education (RAIVE), in order to skirt the mainstream process. This organization is not recognized by any mainstream veterinary group, just as the alternative board certification in homeopathy created by the AVH is not recognized by the AVMA as a legitimate specialty board. These are all examples of the AVH attempted to force homeopathy to be judged by different standards from scientific medicine, standards set by homeopaths. The lawsuit was dismissed by the court in 2012, and RACE does not currently accept homeopathy course as approved CE.

Page 7, item III A: The statement from NCCAM that “Rigorous, well-designed clinical trials for many CAM therapies are often lacking; therefore, the safety and effectiveness of many CAM therapies are uncertain” also applies to the 50% (about 1500) of conventional therapies that are also of unknown effectiveness because of lack of well-designed research. (Clinical Evidence editors, HOC committee 2010) In addition, NCCAM still includes homeopathy in its list of Complementary and Alternative Medicine research that it will fund. (NCCAM)

Simply untrue. While there is rarely perfect evidence for any practice, the evidence base is far stronger for conventional medicine than for homeopathy. (Imrie, R. Ramey, D. The evidence for evidence-based medicine. Complementary Therapies in Medicine (2000), 8, 123-126.) A survey of the literature shows that in the following areas of conventional medicine, the majority of practices are based on compelling scientific evidence:

96.7% of anesthetic interventions (32% by RCT, UK)

approximately 77% of dermatologic out-patient therapy (38% by RCT, Denmark)

64.8% of ‘major therapeutic interventions’ in an internal medicine clinic (57% by RCT, Canada)

95% of surgical interventions in one practice (24% by RCT, UK)

77% of pediatric surgical interventions (11% by RCT, UK)

65% of psychiatric interventions (65% by RCT, UK)

81% of interventions in general practice (25.5% by RCT, UK)

82% of general medical interventions (53% by RCT, UK)

55% of general practice interventions (38% by RCT, Spain)

78% of laparoscopic procedures (50% by RCT, France)

45% of primary hematology-oncology interventions (24% by RCT, USA)

84% of internal medicine interventions (50% by RCT, Sweden)

97% of pediatric surgical interventions (26% by RCT, UK)

70% of primary therapeutic decisions in a clinical hematology practice (22% by RCT, UK)

72.5% of interventions in a community pediatric practice (39.9% by RCT, UK)

Thus, published results show an average of 37.02% of interventions are supported by RCT (median = 38%). They show an average of 76% of interventions are supported by some form of compelling evidence (median = 78%).

We also wish to note:

the Banerji protocol (using homeopathic remedies) Best Case Series on cancer was accepted by NCCAM and NCI at NIH. It was presented to the Cancer Advisory Panel for Complementary and Alternative Medicines. NCI is devising “Practice Outcomes Monitoring and Evaluation Systems Study for Bronchogenic Carcinoma” at their  clinic, with a goal of designing a protocol for treatment of these cases at institutions in the US. (Banerji 2007) The NIH has asked for animal studies before final approval, and currently a board-certified veterinary oncologist is working with the proponents of the Protocol to develop a design for the study.

After 200 years, the best homeopathy can show is a “best case series?” It is well-established that case reports and case series are useful for generating hypotheses, not proving or disproving them. And NCCAM has a long history of funding ridiculous homeopathy research which identifies no benefits but doesn’t discourage homeopaths either.

The Case Against Homeopathy cites numerous systematic reviews of clinical trials, a much higher level of evidence, which shows homeopathy does not work.

In conventional science, radical ideas are proven or disproven, and accepted or rejected accordingly, much more quickly. The notion that Helicobacter caused GI ulcers was radical when proposed in 1982 and had won a Nobel prize by 2005. This was because compelling evidence at all levels, including high-quality clinical trials, was developed. Homeopathy has failed to do this but proponents refuse to accept this and continue to argue for more research. How long is it reasonable to continue investigating despite persistent failure when the notion is theoretically impossible and incompatible with established science to begin with? As the House of Commons Committee concluded, “There has been enough testing of homeopathy and plenty of evidence showing that it is not efficacious. Competition for research funding is fierce and we cannot see how further research on the efficacy of homeopathy is justified in the face of competing priorities.”

Page 8:

Thefourth paragraph describing “sympathetic magic” has nothing whatsoever to do with the way that homeopathic remedies are selected.

Sympathetic magic is a term from cultural anthropology. The theory of sympathetic magic was first developed by Sir James George Frazer in The Golden Bough. He further subcategorised sympathetic magic into two varieties: that relying on similarity, and that relying on contact or ‘contagion’ (emphasis added):

“If we analyze the principles of thought on which magic is based, they will probably be found to resolve themselves into two: first, that like produces like, or that an effect resembles its cause; and, second, that things which have once been in contact with each other continue to act on each other at a distance after the physical contact has been severed. The former principle may be called the Law of Similarity, the latter the Law of Contact or Contagion. From the first of these principles, namely the Law of Similarity, the magician infers that he can produce any effect he desires merely by imitating it: from the second he infers that whatever he does to a material object will affect equally the person with whom the object was once in contact, whether it formed part of his body or not.”

Homeopathy is a classic example of this variety of pre-scientific superstition.

The paragraph describing what one is able to buy in a homeopathic preparation also has nothing to do with the homeopathic idea of “like cures like.”

These examples illustrate the fact that homeopathic remedies are produced from starting materials that have no plausible connection to any disease etiology. The basis for such choices is pre-scientific superstition, including the notion that anything which causes symptoms of illness in a healthy person can be used to combat those same symptoms, regardless of their cause, in a patient.

Vaccines and some conventional medications, such as nitroglycerin for angina, stimulants for attention-deficit hyperactivity disorder, and digoxin for congestive heart failure match the “like cures like” principle.

Again, untrue. Vaccination doesn’t work because of the “like cures like” principle. Vaccine antigens stimulate a specific immune response to a particular antigen from a pathogen by a mechanism that has been intensively investigated and characterized in detail. There are many different kinds of vaccines (whole cell, protein-based, DNA-based, killed and modified live, etc) which are developed and which function to treat or prevent specific diseases according to the pathogenesis of those diseases.

This is drastically different from a magical principle of “like cures like” that is applied to every medical condition regardless of the etiology or pathogenesis. The superficial similarity of vaccines using small (but measurable and highly specific) doses of an antigen and homeopathy using small (and usually non-existent) doses of a starting material is not a true correspondence between the theories behind the two interventions, nor does it demonstrate that homeopathy works. Even so-called “nosodes” homeopathic “vaccines” made from material gathered from a sick individual and diluted and shaken until nothing remains then used to treat or prevent that illness in a real patient, have been proven not to work (e.g. Larson L., Wynn S., and Schultz R.D. A Canine Parvovirus Nosode Study. Proceedings of the Second Annual Midwest Holistic Veterinary Conference 1996.)

Page 14, Item II B states “The AVMA requires specialty boards to demonstrate “a substantial body of scientific  knowledge, ” and does not recognize the Academy of Veterinary homeopathy certification process due to the failure to meet this requirement.” The Academy never applied forspecialtyboard certificationand so has never been judged by AVMA or the ABVS for any body of scientific knowledge. (This was verified by both the Academy of Veterinary Homeopathy and by the American Board of Veterinary Specialties in November 2012.)

The AVH has not applied because they know they cannot meet the standard. Human homeopathy is also not recognized as a medical specialty. Unless homeopaths can meet these standards and obtain this status, they have no legitimate claim to any specialized expertise that must be acknowledged or deferred to.

Page 15, item IIA quotes items about the British Medical Association dating from an anti-homeopathy campaign in that countryduring the year of 2010. The statements attributed to the British Medical Association are not found on their website. Instead their websitesuppliesinformation about the Society of Homeopaths, the Faculty of Homeopathy, and the regulation of homeopathic medicines, as well as the Complementary and Natural Healthcare Council which informally regulates homeopathy as well as other modalities.In addition, a recent article in the Sept 14 isue of the British Medical Journal was favorable, stating “Modern medicine has real capacity to do harm but often minimal good; homeopathy has minimal capacity to do harm but real capacity to do good. Homeopathy is an easy target; we would be better to focus on the failings of conventional medicine. Homeopathy is bad science but good medicine.” (Spence, 2012)

A small number of individual physicians, like individual veterinarians, may support homeopathy, but it is not accepted as legitimate medicine by the BMA or mainstream medicine. At a BMA conference in 2010 voted overwhelmingly in favour of banning homeopathic remedies being funded by the NHS and withdrawing backing for the UK’s four homeopathic hospitals. They added that NHS doctors should not be given homeopathy training and remedies should be taken off shelves “labelled medicines” and put on shelves “labelled placebos”.( http://www.nursingtimes.net/whats-new-in-nursing/primary-care/bma-votes-against-homeopathy-funding/5016611.article, http://www.telegraph.co.uk/health/healthnews/7861240/Chemists-should-be-forced-to-label-homeopathic-remedies-as-placebos-say-doctors.html )

One general comment about foreign organizations(cited starting on page 15):

The EU recognizes homeopathy. Germany, France, and India incorporate homeopathy as part of their health systems. The British government has pointed out to the HOC Committee that if they were to enact their recommendations, it would breach their treaty with the EU.(Secretary of State for Health, 2010)

Numerous veterinary and human medical groups have acknowledged that homeopathy is not a legitimate therapy. Political pressure to refrain from such a declaration is stronger in some places than others, but this has nothing to do with the state of the scientific evidence or the truth of the matter.

As examples:

In the UK, in December 2011, the Veterinary Medicines Directorate (VMD) in the Department for the Environment Food and Rural Affairs (Defra) – which governs the use of medicines in animals – made clear that homeopathic treatments could only be classed as medicines, and thus prescribed by vets, if they were able to demonstrate efficacy. In the past year the British Medical Association has adopted an extremely robust approach on the issue, rejecting the use of homeopathy by the British National Health Service and calling for homeopathic products to be stored away from medicines in pharmacies and chemist shops on shelves marked “placebos”. In Sweden, veterinarians are prohibited from prescribing homeopathic remedies. In November 2005 the Federation of Veterinarians in Europe (FVE) issued a strategy document including the statement that the veterinary profession is rooted in science and evidence-based veterinary medicine. In the explanatory discussion of this strategy document it was explicitly stated that the FVE rejects non-evidence based medicines such as homeopathy. Earlier in 2005 the European Board of Veterinary Specialisation (EBVS) made a clear statement with regard to alternative modes of treatment: The EBVS only recognises scientific, evidence-based veterinary medicine complying with animal welfare legislation. Specialists or colleges practising or supporting implausible treatments with no proof of effectiveness run the risk of withdrawal of their specialist status. No credit points can be granted for education or training in these so-called supplementary, complementary and alternative modes of treatment. In October 2006, the general assembly of the Royal Netherlands Veterinary Association agreed to discontinue the official status of the group of veterinarians working with homeopathy.

page 16: Item IIIC “the FDA …  has made no attempts to regulate their use or require any evidence of safety and efficacy”

ignores the fact that the proper preparation of homeopathic remedies is recognized by the FDA and is part of their Pharmacopoeia.

You can read FDA regulations regarding homeopathic remedies here: http://www.fda.gov/ICECI/ComplianceManuals/CompliancePolicyGuidanceManual/ucm074360.htm(accessed 10/29/2012)

Homeopathy was grandfathered into the 1938 law establishing the FDA because it was proposed by a Senator who was also a homeopath. What this means is that homeopathic remedies do not have to prove safety and efficacy through scientific testing as conventional medicines do. This exception to the usual standards of scientific evidence is a historical and political one, but it is not an endorsement of homeopathy by the FDA. As the National Center for Complementary and Alternative Medicine states, “FDA does not evaluate the remedies for safety or effectiveness.” The FDA’s own web site state, “FDA is not aware of scientific evidence to support homeopathy as effective.”( http://labels.fda.gov/)

As for veterinary homeopathy, the FDA has stated that the grandfathering of homeopathic remedies for human use into drug laws do not apply to veterinary medicine. In a 2006 statement regarding regulation of milk pasteurization, for example, the agency stated, “Homeopathy is an alternative therapeutic modality developed in the late 1700’s by a German physician for use in humans. Homeopathic medicine is considered an unconventional form of veterinary practice. FDA can find no justification for regulating veterinary homeopathic drugs any differently from other drugs subject to the FFD&CA. There are currently no FDA approved homeopathic drugs for veterinary use.” The FDAs CVM has chosen not to enforce this law, as yet another  political concession to homeopaths, but this by no means constitutes FDA approval of homeopathic remedies as effective the way a drug approval does. (www.homeopathicpharmacy.org/pdf/articles/vet_drugs.pdf)

“The FDA CVM identifies all drugs intended for animal use which have not passed the new drug approval process as unapproved animals drugs, and this is true for homeopathic remedies as well (http://www.fda.gov/AnimalVeterinary/ResourcesforYou/ucm268128.htm). Use of such drugs are tolerated, but veterinary use of homeopathy is not approved or endorsed by the FDA.”

Page 16, Item III D:

European regulations (the regulations in question are from DIRECTIVE 2001/83/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 6 November 2001 on the Community code relating to medicinal products for human use.)

Despite what is implied, those regulations were established for “clinical trials, to provide a special, simplified registration procedure for those homeopathic medicinal products which are placed on the market without therapeutic indications.” (Emphasis is the author’s.) In other words, instead of labeling them “for hepatitis” the labelwould have no indications. They also have to be in a form “which do(es) not present a risk for the patient.”

“The smallest dose that results in the obligation to submit a doctor’s prescription”does not mean inactive. Advil is active, as is prescription-level amounts of ibuprofen, but Advil does not need a doctor’s prescription.

In addition “acknowledged to have no recognized therapeutic use” is for those remedies eligible for the simplified procedure. The rest of the regulations say “The usual rules governing the authorization to market medicinal products should be applied to homeopathic medicinal products placed on the market with therapeutic indications.”Despite the implications, the rest of the regulations make it clear that these regulations recognize that there are homeopathic remedies with therapeutic use.

Nonsense. The language of these regulations is intended to allow homeopathic remedies to be marketed despite having no proof of efficacy for specific clinical indications. The caveat is that they cannot claim such an indication on the label. This is one more political accommodation for homeopaths that exempts homeopathy from the standards of evidence to which conventional medicine is held, and the AVMA should not continue to tacitly approve of such a double standard by refraining from stating the obvious: that homeopathy has failed the standards of proof expected of legitimate scientific medical therapies.

“3. The label indicates the absence of any recognized therapeutic use” is describing the label, not the remedy.

Labels are regulated in both Europe and the U.S. as a way of ensuring that false claims are not made regarding safety and efficacy. If a product cannot be labeled as having a specific effect, that is because it has not been scientifically shown to have that effect. That’s the whole purpose of a drug label.

Page 17, III E

“NHMRC’s position is that it is unethical for health practitioners to treat patients using homeopathy,”

The current Homeopathic Working Committee, working until June 30 2013, is creating an information paper and position statement on homeopathy. The draft is not published on their website and the 2010 paper cannot be considered an official representation of their opinion.(NHMRC 2012)

While not yet official policy, it indicates that before the application of outside political pressure, groups like the Homeopathic Working Committee of the NHMRC and the House of Commons Science and Technology Committee consistently come to the conclusion, when evaluating the evidence, that homeopathy is ineffective. Whether these conclusions are then adopted as official policy depends, as in the case of Resolution 3, on political factors as well as scientific evidence.

Page 17, item IV A discussing “The dangers of homeopathy” states “There have been some reports of detectable heavy metal contamination of homeopathic remedies.”

There is a single citation which reports contamination of products from Croatia. Products used in the US are of American and British origin.This was cited by the flawed HOC Committee report.

That was simply one example. There is ample evidence of the harm from the use of homeopathy, both direct and indirect.

For example, Posadzki P, Alotaibi A, Ernst E. Adverse effects of homeopathy: a systematic review of published case reports and case series. Int J Clin Pract. 2012 Dec;66(12):1178-88 states:

“In total, 38 primary reports met our inclusion criteria. Of those, 30 pertained to direct AEs of homeopathic remedies; and eight were related to AEs caused by the substitution of conventional medicine with homeopathy. The total number of patients who experienced AEs of homeopathy amounted to 1159. Overall, AEs ranged from mild-to-severe and included four fatalities. The most common AEs were allergic reactions and intoxications. Rhus toxidendron was the most frequently implicated homeopathic remedy. Conclusion:? Homeopathy has the potential to harm patients and consumers in both direct and indirect ways. Clinicians should be aware of its risks and advise their patients accordingly.”

Similarly, Freckelton I. Death by homeopathy: issues for civil, criminal and coronial law and for health service policy. J Law Med. 2012 Mar;19(3):454-78 states:

“In India, England, New South Wales and Western Australia civil, criminal and coronial decisions have reached deeply troubling conclusions about homoeopaths and the risk that they pose for counter-therapeutic outcomes, including the causing of deaths. The legal decisions, in conjunction with the recent analyses of homoeopathy’s claims, are such as to raise confronting health care and legal issues relating to matters as diverse as consumer protection and criminal liability. They suggest that the profession is not suitable for formal registration and regulation lest such a status lend to it a legitimacy that it does not warrant.”

Page 18 states “not all homeopathic medicines are administered at a high dilution.” This istrue for a wide variety of homeopathic medicines. This negates the general representation of the Connecticut white paper that homeopathic remedies have no effect because of their ultra-high dilutions.

Yet the vast majority are, and the remainder have been exempted from demonstrating safety and efficacy by scientific investigation by the label “homeopathic.” If they are truly effective, there should be clinical trial evidence to show this, and there is not.

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Evidence Update-Most Homemade Cancer Diets for Dogs are Inadequate

I have often discussed the problems with homemade pet diets, which are frequently recommended in books and websites that complain about commercial food or proclaim some magic method for preventing or curing disease. Raw diets, grain free diets, and other fads often involve making pet food at home from recipes from self-proclaimed experts in nutrition, though there are also commercial versions of each fad available not long after it takes hold. Of course, the only real experts in pet nutrition are those board certified by the American College of Veterinary Nutrition. And while there is ample evidence that homemade diets are often nutritionally inadequate, (e.g. 1, 2) most of the scary claims about commercial diets are just myths and misconceptions.

A recent study has reinforced these already well-established points.

Heinze CR, Gomez FC, Freeman LM. Assessment of commercial diets and recipes for home-prepared diets recommended for dogs with cancer. J Am Vet Med Assoc. 2012 Dec 1;241(11):1453-60. doi: 10.2460/javma.241.11.1453.

This study looked at recipes from books and web sites that recommended diets for dogs with cancer, as well as commercial diets marketed for use in canine cancer patients, and evaluated the nutritional adequacy of the diets based on established AAFCO or NRC guidelines. The findings were quite clear, and the recommendations consistent with those veterinary nutritionists have been making for some time.

Published recipes of home-prepared diets for pets with various health conditions are rarely nutritionally adequate. None of the 27 recipes identified and evaluated met NRC RA or AAFCO nutrient profiles for all essential nutrients. In some cases, the recipes contained excessive, potentially toxic amounts of nutrients.

Recipes formulated or provided by veterinarians were not more nutritionally sound than were recipes formulated or provided by nonveterinarians.

Only 2 of 39 (5.1%) commercial diets had passed AAFCO feeding trials (one for adult maintenance and the other for all life stages). The majority (35/39 [89.7%]) of the diets were formulated to meet AAFCO nutrient profiles for all life stages (27 diets) or adult maintenance (8 diets

There is a paucity of experimental data that support specific nutrient profiles or ingredients for dogs with cancer. Dogs with cancer do not have higher or lower requirements for protein, fat, calories, or any other specific nutrients, compared with requirements for healthy dogs. Therefore, it is of concern that none of the recipes for home-prepared diets met NRC RA or AAFCO nutrient profiles for adult maintenance in dogs… All of these inadequate diets have the potential to cause nutritional disease at a time when nutrition should be optimized to provide maximum metabolic support and immune system function and to help decrease adverse effects attributable to cancer treatments.

Commercial diets and recipes of home-prepared diets reflected the current popularity of grain-free diets. No data support health benefits of non-grain sources of carbohydrate over carbohydrates provided by grains; however, many manufacturers still tout the nutritional superiority of grain-free products.

Grain-free diets are often marketed as lower in carbohydrate content, but this is not a consistent finding. Approximately one-third of the recipes of grain-free home-prepared diets and commercial diets did not meet the defined criteria for low-carbohydrate diets.

Low-carbohydrate diets are commonly recommended for dogs with cancer on the basis that many cancer cells use aerobic glycolysis and fermentation of pyruvate to lactate as a main source of energy… it is theorized that feeding a low-carbohydrate diet could effectively starve cancer cells through a decrease in the supply of glucose. However, despite the fact that this theory has been in existence for nearly a century, minimal data have been published to support the tangible benefits of low-carbohydrate diets for any species of animal with cancer. To our knowledge, there are no published data to support the contention that low-carbohydrate diets are of clinical benefit with regard to tumor growth, disease-free interval, or survival time in dogs, and further studies are required before appropriate recommendations can be made.

The number of recommendations for feeding raw meat diets to cancer patients is a concern because contamination with pathological bacteria has been reported for raw meat for human consumption and for commercial raw diets. Cancer patients, even those not receiving chemotherapy, likely have some degree of altered immunoregulation, and many dogs receiving chemotherapy are clinically immunosuppressed, which dramatically increases the risk of illness or even death from contaminated food sources. In humans, the risk of illness attributable to foodborne bacteria in cancer patients is such a concern that patients receiving chemotherapy are commonly advised to eat raw fruits and vegetables only when at home.

It is possible that feeding a diet that does not meet AAFCO recommendations or NRC RAs for various nutrients may not cause overt clinical disease. Although some nutrient deficiencies (eg, thiamine or taurine) can be evident in adult animals after a food deficient in those nutrients is fed for weeks to months, it can be months to years before clinical signs are evident for other nutrient deficiencies (eg, calcium in an adult animal). The status of many nutrients is not easily determined, and the first clinical signs of deficiency may be catastrophic (calcium deficiency resulting in osteopenia and pathological fractures or taurine deficiency resulting in dilated cardiomyopathy).

Currently, the authors are aware of no evidence to suggest that cancer patients have nutrient needs that differ dramatically from maintenance requirements. Many dog owners change to home-prepared diets because of an overall perception that they are healthier than commercial diets, rather than because they provide specific nutrient profiles. Thus, it appears appropriate that home-prepared diets be formulated to meet nutrient guidelines similar to those of commercial products.

Bottom Line

Homemade diet recipes are almost always nutritionally inadequate, even if formulated by a veterinarian (unless they are a board-certified nutritionist)

There is no evidence for benefits from current nutritional fads such as raw or grain-free diets, but there is the potential for harm from these diets.

Commercial diets are consistently more appropriate nutritionally than homemade diets.

There is little evidence to support the idea that cancer patients should be fed a different diet from healthy dogs (with the possible exception of extra fatty acid supplementation).

Posted in Nutrition | 61 Comments

What “Experts” in Homeopathy are Supposed to Believe

One of the most compelling letters of support for the AVMA resolution on homeopathy came from a source that might seem unexpeted, Dr. Narda Robinson, Assistant Professor of Complementary and Alternative Medicine at the Colorado State University Veterinary School of Veterinary Medicine. Dr. Robinson is that rare bird, a practitioner of some alternative therapies who is also a proponent of taking an evidence-based approach to CAM. I think of her as sort of the Edzard Ernst of veterinary medicine. Dr. Robinson and I disagree (sometimes right in the comments section of this blog) about a number of therapies, but her genuine interest in a rigorous application of real science to the evaluation of CAM is refreshing and desperately needed in the field, and I respect her opinion even when I dont’ agree with it.

And like Dr. Ernst, Dr. Robinson has paid a price for her integrity and willingness to reject pseudoscience like homeopathy despite its affiliation with therapies she uses that are also lumped under the expansive and vague umbrella term of CAM.  She is often upraided as or more harshly even than I am by proponents of practices she challenges.

Dr. Robinson has graciously allowed me to post the letter she submitted in support of AVMA Resolution 3. It refers specifically to the Academy of Veterinary Homeopathy Standards of Practice, which I have written about before. These standards are inherently ridiculous in that they attempt to create the aura of legitimate scientific expertise in a field that is fundamentally incompatible with modern science. However, the are most worrisome in that they reveal the often hidden belief among too many homeopaths that hoemopathic treatment should be seen as an alternative to conventional, sceintific medical care. This attitude places our patients at risk and represents the greatest danger of homeopathy, which of course is rarely directly harmful since it only a placebo.

December 15, 2012
To: AVMA House of Delegates
Re: Comment on Proposed Resolution 3 

Dear Delegates,

I am writing to convey strong support for proposed Resolution 3, which recommends that the AVMA adopt a policy stating that homeopathy is ineffective and should be discouraged as a veterinary therapy.

I find especially telling and disturbing the “Standards of Practice” put forth by the Academy of Veterinary Homeopathy (AVH), the sole certifying body for veterinary homeopathy.1 The AVH stresses that consumers interested in pursuing homeopathic treatment for their animal consult a certified veterinary homeopath (CVH) so that they “will know that the AVH Standards of Practice is (sic) being upheld and that their veterinary homeopath is practicing according to the laws of homeopathy.” In fact, all AVH members must agree to the AVH Standards of Practice.2 3 Considering that the American Holistic Veterinary Medical Association has insisted that so-called “experts” in homeopathy participate in discussions that evaluate the legitimacy or effectiveness of this approach,4 it would be wise to closely examine the standards that homeopathic experts (CVH) are exhorted to uphold.

Of the 15 standards posted by the AVH, the first 8 suffice to highlight the risk of delivering ineffective healthcare to animals. They also illustrate how homeopathy might harm animals and threaten public health by omitting proven, scientifically based, medical and preventive measures designed to treat illness early and effectively as well as limit the spread of infectious disease.

Specifically, the AVH Standards of Practice state:

1) Only the remedy that is homeopathic to the patient is to be used.

2) Drugs and methods of treatment which are not homeopathic to the case are to be avoided because of the possibility of interference with the progress of cure.

With these recommendations, the AVH is essentially advising veterinarians to avoid vaccines, antibiotics, analgesics, cardiac medications, anti-epileptics, anti-inflammatories, chemotherapeutic drugs, immunosuppressant medications, inhalational anesthetics, and more. This denies animals safe, proven, clinically meaningful treatment and risks spreading communicable and preventable diseases to other animals and humans. The AVH cites the basis of this standard from an early 19th century tome: “Drugs, herbs and other forms of treatment prevent cure and cause ultimate harm to the patient.” 6

3) Use of acupuncture and moxa is not compatible with homeopathic treatment because of its effect on the vital force of the patient.

4) Treatment of symptoms by electrical or electromagnetic application is to be avoided because of its tendency to suppress symptoms in the patient. Use of electricity and effects of magnets are suitable in treatment when administered according to homeopathic indications only.

The recommendation to exclude therapies based on an abstract concept of “vital force” interference illustrates how unscientific thought from a bygone era continues to influence those who use homeopathy today.

5) Only one homeopathic medicine is to be given at one time.

In practice, this standard of practice translates into a homeopath guessing at a remedy, treating an animal with a treatment indistinguishable from a placebo for several weeks or months while withholding appropriate medications. If the animal fails to improve, the homeopathic veterinarian attempts to cure with another placebo for several weeks. How long must an animal suffer before known and effective care is offered? Sometimes such “trials” continue for months, thereby diminishing conventional care options

by allowing illnesses to worsen and pain to reach unbearable levels.

6) Medicines are most suitably given by mouth.

This directive, adapted like the others from an early 19th century homeopathic text7, was formulated prior to the development of the modern hypodermic needle in 1853 and the disposable syringe in 1956.

7) The patient should receive nutritious food that does not, in itself, have medicinal effects.

This standard contradicts the advances made by nutritional medicine and the research performed on therapeutic diets for organ failure or nutrient intolerance, posing further harm for animals by denying them preventive and restorative dietary modifications.

8) Symptoms on the skin or surface of the body that have expressed as a localized lesion are not to be treated in a vigorous way with the intent to cause their disappearance or by surgery to remove them. These are to be treated primarily by internal homeopathic treatment.

Recommending that veterinarians allow skin lesions to grow robs the animal of effective treatment for known dermatologic conditions. Cancerous lesions that could have been cured with early intervention may enlarge or metastasize, requiring painful, costly, and invasive care or palliation. This error of omission stems from an early 19th century idea, now perpetuated by the AVH: “Hahnemann explains that local lesions are expressions of internal disease and that eradication of this expression before the internal disease is treated curatively harms the patient and makes curative treatment impossible.”8 As the Iowa Board of Medicine contends, “The public needs to be informed that this practice [homeopathy] may not be useful and that it may divert individuals from other, more efficacious modalities of care while taking precious time for homeopathy to take effect. In addition, patients may spend considerable money for treatments that may not be effective. The Board’s position is ‘buyer beware’.”9

Conclusion

In summary, the Standards of Practice put forth by the AVH to be upheld by all members, including its “most expert” certified veterinary homeopaths, recommend that veterinarians commit serious, potentially life-threatening errors of omission that pose substantial risk to both animal and public health. By upholding this resolution, the AVMA will send a clear message to consumers about the risks to which they expose their animal and, possibly, themselves if they opt for what is essentially placebo medicine in place of effective, modern, scientific healthcare.

Sincerely,

Narda G. Robinson, DO, DVM, MS, FAAMA
Director, CSU Center for Comparative and Integrative Pain Medicine
Assistant Professor of Complementary and Alternative Medicine

 

References

1 The Academy of Veterinary Homeopathy (AVH) web page. Why Should I Become a Certified Veterinary Homeopathy? http://www.theavh.org/certification/index.php .

2 The AVH web page. http://www.theavh.org/referral/index.php.

3 The AVH membership application. http://www.theavh.org/documents/AVH%20Membership%20app.pdf . The application form states, “Our organization is founded on these principles and the preservation of proper application of homeopathic principles is our cornerstone…We have found that the correct application of these principles creates a higher level of success in homeopathic practice…We do not require our members to practice homeopathy to the exclusion of other modalities but we do require that, in cases where homeopathy is used, it be used according to these principles.”

4 American Holistic Veterinary Medical Association website homepage. http://www.ahvma.org .

5 The AVH web page. Standards of Practice and Purpose of the Academy of Veterinary Homeopathy.http://www.theavh.org/referral/sop.php.

6 The AVH membership application. http://www.theavh.org/documents/AVH%20Membership%20app.pdf . Original reference cited by AVH as Hahnemann S. Organon of Medicine, 6th edition, paragraphs 23, 25-45, 69, and 291.

7 Hahnemann S. Organon of Medicine, 6th edition. Denoted in the AVH Standards of Practice as their main source. 1st edition, 1810; 6th edition, completed in 1842. Translated into English by Naude A, 1982.

8 The AVH. Member Application form, available at http://www.theavh.org/documents/AVH%20Membership%20app.pdf .

9 Iowa Board of Medicine. A policy statement on homeopathy. Approved by the Board on June 28, 2001. http://medicalboard.iowa.gov/policies/homeopathy.html

 

 

Posted in Homeopathy | 3 Comments