Evidence Update: Dodds Study on Vaccine Dose in Small Breed Dogs

I have been able to get a look at the published paper for the study I recently discussed by Dr. Jean Dodds investigating  giving lower doses of vaccine to small breed dogs. There is nothing in the published report that changes my earlier conclusion. This study adds nothing of substance to our understanding of optimal vaccination practices. In design and execution, it is simply a marketing tool to promote a set of pre-existing beliefs about vaccination, and in itself does not help to clarify what optimal vaccination practices might be.

The argument Dr. Dodds seems to be making contains a number of elements I agree with and believe to be supported by good science:

  1. The effectiveness and duration of immunity vary by vaccine type and with many other factors, but in general core canine vaccines are very effective at preventing illness and likely most pets who receive the initial vaccine series at the appropriate time are well-protected for at least 3 years and probably much longer.
  2. Vaccines can have adverse effects, and while these are rare they can be potentially serious. The precise factors that make some individuals more susceptible to such reactions than others are unclear, but size appears to be a factor, with small-breed dogs reporting more reactions that larger breeds. (this is quite a bit more restrained than previous statements she has made about “vaccinosis” in small animals)
  3. Avoiding unnecessary vaccination in animals already immune to particular infectious diseases is a desirable goal.
  4. Titers can often tell us if an animal is already immune, depending on the disease in question, though they generally cannot tell us if the animal is vulnerable to a disease since they only reflect part of the overall immune response.

She adds to these a number of claims which are not supported by good evidence, including most of the claims related to this specific study.

The dose of canine distemper virus (CDV) and canine parvovirus vaccine (CPV) vaccines can be reduced to 50%, but not more, for small breed and small mixed breed type dogs, based on body weight, and still convey full duration of immunity.

She states this in the introduction, indicating it is a pre-existing belief she intends to buttress with this study. However, her citations for this very clear and specific claim include three of her other papers expressing this opinion and an editorial from 1999 discussing concerns among practitioners about vaccination practices. No specific research is cited that supports this claim. And elsewhere in the paper, she makes it clear that the claim is actually based primarily on her personal experience, aka anecdotal evidence.

In the informed consent sheet for clients, she says “Clinical experience has shown…” and “One of the principal investigators has nearly five decades of clinical and research experience with vaccinations in companion animals. This experience has shown…” and then repeats this claim. It is not a claim supported by research evidence but simply something she has come to believe based on patients she has seen, and it should be clearly presented as such, as mere opinion appropriate for generating a hypothesis but not for making confident claims.

The only relevant research she cites is one study in which children were shown to have an adequate protective response to a lower quantity of Hepatitis B vaccine. This was tested primarily to reduce the cost of vaccination and make vaccination available to more people, not to avoid adverse effects. But in any case, it doesn’t validate the general concept that vaccines should be dosed by body weight, which is not accepted vaccine science in human or veterinary medicine.

As for the study itself, it suffers from many serious flaws that likely would have prevented publication in an ordinary veterinary journal, which may be part of why it appears in the journal of the AHVMA.

The first issue is selection bias. The subjects were recruited by an announcement on Dr. Dodds’ web page and emails to “holistic veterinarians.” This does not appear to have been very successful since only 13 animals were recruited. But in any case, these likely represent an unusual patient population, since “holistic” veterinarians, and of course Dr. Dodds, recommend quite different approaches to preventative and therapeutic healthcare than most vets, including different vaccination practices. These animals may not be sufficiently similar to pets that receive standard veterinary care, including with respect to their vaccine history. This would limit the ability to generalize any results to other populations.

Another problem was the lack of any standard definition for “a half dose of vaccine,” which is what participating vets were told to give. While all used the same specific vaccine, this vague description of the main intervention being tested allows for a lot of unpredictable variation from subject to subject, and makes it hard to compare with any other research that may be done. The specific antigenic load given would be much more useful information at this stage of research.

A core problem with the study is that it did not address any of the underlying issues of whether giving a half dose of vaccine would protect dogs as well from disease or reduce the number of adverse vaccine reactions. Neither of these subjects was evaluated in any of the study dogs. All that was done was that antibody levels were measured before vaccination and at 4 and 6 months later. Here are the main results:

DODDS - J Am Hol Vet Med Assoc  table 1

All dogs had titers considered indication of immunity before being vaccinated. Most, but not all, dogs had an increase in their titer after vaccination at 4 months (9/13 for CPV and 11/13 for CDV) and 6 months (6/8 for CPV and 3/8 for CDV). This tells us, at most, that a smaller amount of a vaccine than usually given promotes some increase in antibody levels for CPV and CDV for some dogs. This, unfortunately, tells nothing about how to best vaccinate dogs to protect them from these diseases while minimizing any adverse health effects.

(The difference in the number of samples at 4 and 6 months reflected that while all dogs had blood samples taken at both times, “5 dogs had samples drawn at 6 months but these were inadvertently discarded.” Accidentally throwing out nearly ¼ of your samples is a pretty serious error in any study, and raises questions about the validity of the data as well as the conclusions.)

These data, even if accepted as legitimate, do not answer any of the pertinent questions, such as whether dogs receiving half of the usual vaccine dose would be protected as well long-term or healthier and less likely to experience health problems than dogs receiving the usual vaccine dose. The study doesn’t, in other words, provide any real evidence to support or refute the claims Dr. Dodds and many other “holistic” vets make about the best vaccination practices. And given she has admitted that she had no intention of following these dogs further or conducting any larger trials based on this “pilot” study, it is pretty clear that the only purpose of this study was to generate ammunition for a marketing campaign to promote ideas about vaccination that Dr. Dodds has developed entirely based on personal experience and belief.

I have addressed both the evidence concerning risks and benefits of vaccination and the issue of using titers to help make vaccination decisions. Limitations in the available evidence make a variety of different practices equally justifiable. While I probably vaccinate less than many conventional vets, I refrain from making definitive statements beyond the evidence about the effects of various approaches to vaccination. Dr. Dodds’ position is somewhat intermediate between the rabidly anti-vaccine views of some holistic vets and the unthinking annual vaccination too often still recommended by many conventional vets, and she and I are probably not too far apart in principle. However, she chooses to emphasize the risks of vaccination (especially in places where, unlike this article, she talks about nonsense like “vaccinosis”), and she makes confident claims about the best vaccination approach that she presents as science-based but which really are simply her opinion.

In this study, she has provided the illusion of scientific evidence to support these claims, but the reality is that this study is too flawed in design and execution to add anything useful to the question. Unfortunately, Dr. Dodds and others are already promoting it widely as evidence that their preferred vaccination approaches are better for patients than those of others, including the current most evidence-based guidelines. This is a misleading misuse of science consistent, unfortunately, with her approach in many other areas.

Posted in Vaccines | 1 Comment

“Traditional Chinese” Emergency and Critical Care Medicine?

I ran across this article recently with a board-certified specialist in veterinary emergency medicine recommending so-called Traditional Chinese Veterinary Medicine (TCVM) for critically ill patients.

As I’ve discussed in detail, there is some very limited evidence for a few potentially useful effects from passing electricity through acupuncture needles. However, the bulk of TCVM practice, and all of the theories behind it, is pure folk mythology and pseudoscience. It is always amazing and disappointing to see someone with an advanced scientific education treating such beliefs systems, and the therapies associated with them, as if they were in any way equivalent to science-based medicine or legitimate to experiment with on our sickest patients without good research evidence to support the claims made for them.

Such individuals would never tolerate the same near complete absence of evidence for a conventional drug or therapy. They are willing to give untested chemicals (herbs) and needle patients based solely on individual clinical experience and the belief that these practices have been used historically with success (which is often untrue).

Ultimately, it comes down to believing that a therapy is helpful based on individual clinical experience not only in the absence of high-quality evidence but in the absence of any controlled evidence or even a plausible theory. The history of medicine is one long lesson in why uncontrolled clinical observation is a very, very poor second to scientific research in evaluating the efficacy of our therapies. From bloodletting to internal mammary artery ligation, from Lourdes water to antibiotics for cats with interstitial cystitis, every ineffective therapy ever tried has appeared to work sometimes based on trial-and-error use. Either every possible treatment works for some patients, or clinical observation is an unreliable way to validate our treatments. Personally, I think the case is much stronger for the latter conclusion than the former.

I also think it is more than a question of whether or not we have clinical trial evidence. Of course we lack that for many of our treatments. But even therapies based on sound basic physiology and pre-clinical in vitro and animal model testing fail most of the time when subjected to clinical studies. Isn’t even less likely that a therapy based on Tonifying Yang or Releasing Wind is going to be truly effective? The rationale matters, especially in the absence of good controlled evidence.

Of course, in challenging these beliefs, I am immediately subjected to accusations that I am “closed-minded.” An open mind means not judging automatically and without regard to evidence, but it doesn’t mean not judging. We all have to make judgments about the safety and efficacy of the therapies we use. There is nothing inherently better or fairer about a positive judgment. If someone chooses to believe TCVM or bloodletting, or any other unscientific approach works based on the weak evidence on uncontrolled personal observation, they are not being more fair or open-minded than a critic who asks for better evidence than this before accepting such therapies. They are simply applying a different, looser standard of evidence.

I don’t claim with certainty that these therapies do not work, only that their theoretical foundations are unscientific, which makes the prior probability of their working very low, and that there is no good reason to believe they work in the absence of good-quality evidence to raise this probability. This is not being closed-minded, merely applying the principles of science and evidence-based medicine, which it seems to me have proven their worth quite dramatically compared with history, tradition, and anecdotes.

While this vet is usually careful to recommend these treatments with conventional care or instead of it only if the owner declines conventional treatment, I still can’t help feel it is unethical for a specialist to promote and legitimize such pseudoscience. We are essentially experimenting on sick patients without acknowledging this and claiming to have effective treatments when they are both implausible and not properly tested. We are giving a special pass to something to avoid the usual scientific testing we require of all our other therapies only because someone has slapped the label “alternative” on it.
Here are some examples of the comments in the article that I find disturbing:

If you have a patient that is bleeding post-operatively (post-op spay) or an unstable hemoabdomen that needs to go to the operating room, you can try dry needling Tian-Ping.

One indication for acupuncture could be in a post-op soft palate resection in a brachycephalic dog. By injecting B-12 at An-Shen to help calm a patient instead of writing an order for Acepromazine PRN

there are six typical Traditional Chinese Veterinary Medicine (TCVM) patterns for heart failure….If an owner is unwilling to do MV and the pet has collapse of Yang Qi, points for shock can be used as well.

If you have a feline patient with megacolon, and the owner is unwilling ? or it is too risky ? to place a pet under anesthesia for a de-obstipation, then enemas, lactulose, intravenous fluids and acupuncture can be used. There are 2 typical patterns for the Eastern diagnosis of megacolon, it is either Qi deficiency, or Yin and Blood deficiency. The acupuncture points would be selected based on what pattern they were exhibiting.

We treat many primary IMHAs and when they respond quickly it is great, but often we have patients that do not respond to the typical immunosuppressives. The traditional Chinese medicine pattern would need to be identified since there are different patterns. Typically for an extravascular hemolysis case, the main issues tend to be spleen Qi deficiency/blood deficiency. So selecting acupuncture points that would tonify the Qi/Blood, support the spleen, and immunomodulating points such as (LI-4, LI-10, LI-14, ST-36, GV-14) would be best. If the patient has evidence of intravascular hemolysis, clearing the heat and damp would be important and thus direct your acupuncture approach. The use of herbal therapy is becoming more popular and for a non-responding, primary ITP case Gui Pi Tang may be helpful.

the cat that is having an acute asthma attack that is not responding to typical interventions such as oxygen, steroids, and bronchodilators. Knowing LI-20, Bi-tong and Lung-hui acupuncture points can come in very handy. There are really countless uses for dry needling, aqua and electrical acupuncture in the CCU and it will likely become a more routine treatment in the critical care veterinary setting.

Posted in General | 13 Comments

Alternative Standards for Alternative Continuing Education Courses

I have written several times about the efforts of alternative vets to circumvent the systems intended to ensure quality and scientific legitimacy in continuing education for veterinarians. In brief, most states require vets to regularly take a certain number of hours of continuing education. The idea is that scientific and medical knowledge grows and changes over time. Since states give vets an exclusive monopoly on practicing veterinary medicine, they want to ensure the public is protected against veterinarians who have outdated or inaccurate knowledge and skills.

Such requirements are meaningless if there is no control over the kinds of education vets can use for this license requirement. If I can take a class in origami or a Renaissance poetry, that’s great fun but it doesn’t help ensure I am an up-to-date and competent vet. So most states require continuing education (or CE) courses be accredited to be used for licensure. Vets can still take any courses they want in any subject, they just can’t get credit for them for licensing purposes unless they are accredited.

The American Association of Veterinary State Boards (AAVSB) is the main organization recognized as accrediting CE courses, through its RACE group. Appropriately, RACE requires the content of CE courses have some minimal scientific evidence or compatibility with science.

[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.

This category includes all conventional medical and surgical sub-categories that are evidence based… Based on scientific principles, there must be an established “probability” of success that conforms to the medically accepted and scientifically supported standards of experimental design, data collection and analysis.

  1. Content of a Category One: Scientific Program must be supported by:
  2. Availability of beneficial evidence (peer reviewed journal) OR
  3. Three peer reviewed studies OR

iii. Study review – Case control studies leading to the benefit of the patient OR

  1. Evidence based studies OR
  2. Proven usefulness /effectiveness OR
  3. Evidence of rigorous scientific research OR

vii. FDA (animal approved) objective information/about the product (safety) plus one of the categories above.

RACE does approve some CE offerings involving alternative therapies, but many do not qualify for accreditation due to lack of compliance with RACE requirements for scientific validity. Organizations of alternative medicine providers have often responded to the denial of RACE approval not by producing better scientific support for the disputed content but by circumventing the approval process. The American Holistic Veterinary Medical Association (AHV MA) and other groups have advocated bypassing RACE and getting CE approval directly through the states. Smaller numbers of individuals are better able to influence the political process at the state level, so this has often been a successful strategy.

Also, since the AHVMA has now qualified for a seat in the AVMA House of Delegates, some states automatically accept their content as legitimate CE regardless of scientific validity or RACE approval. House of Delegate membership essentially only requires only a certain number of members who also belong to the AVMA, so it is not a mark of any kind of legitimacy to the mission of the organization. However, it is a useful component to an overall campaign to market alternative medicine, and in this case it facilitates bypassing the usual standards veterinary CE courses must meet.

The Academy of Veterinary Homeopathy (AVH) actually sued AAVSB over denial of RACE approval, unsuccessfully. (1,2)

But the CAVM community has gone even further, creating an alternative CE accreditation board specifically to approve alternative medicine content, RAIVE. As they state on their web site:

The CAVM community now relies on RAIVE to validate their educational meetings. We urge all state boards to do the same for CAVM courses. The opinion of the RACE committee is no longer valid.

Failing to approve every element of their CE offerings, regardless of scientific validity, apparently invalidates the entire CE approval process. The AHVM, RAIVE and other CAVM organizations are now attempting to get state veterinary medical boards to accept RAIVE accreditation as comparable to RACE approval. Washington state, for example, is currently accepting input on a proposal to do just this (The proposal)

The RAIVE web site argues there is no need to demonstrate scientific validity for CE offerings, only that CAVM should be taught by “experts” in that field. As I have pointed out before, that by definition requires that any judgment of CAVM be made by individuals who already believe in its safety and efficacy and have committed themselves to practicing and teaching specific modalities. This effectively eliminates any possibility for falsifying or even significantly challenging these methods, and makes the standard of validity not scientific evidence but expert opinion. It is the perfect closed shop.

The site further specifically states that scientific evidence is a secondary consideration and need only be developed if the methods they advocate are already accepted and taught:

RAIVE recognizes that evidence based medicine does not define the practice of veterinary medicine, but is a process of clinical decision-making, and veterinarians can also benefit from education in emerging subjects with little scientific support. In these cases, RAIVE approved CE must incorporate experts with advanced training or deep clinical experience in these subjects.

RAIVE recognizes that not all CAVM modalities meet the currently accepted standards of evidence. However, RAIVE also recognizes that in order for the evidence to be produced, CE in these modalities must be encouraged in order to develop and strengthen skills in practitioners of these modalities.

So we should teach people to use these methods first, and then maybe test them scientifically later? This effort to avoid the usual standards of evidence that conventional veterinary CE offerings are expected to meet, and to specifically reject scientific testing as the primary standard in favor of individual expertise, reflects the common view often manifest in the CAVM community that science is useful only for proving what one already “knows” from personal experience or for convincing others of the validity of such knowledge. The issue is not whether CAVM methods are or can be scientifically validated. Some practices might meet this standards, and others clearly do not. As I’ve said repeatedly, many aspects of CAVM can and should be investigated scientifically. But others, like Chinese Medicine and Reiki, cannot be because they are belief systems not scientific hypotheses. Others, like homeopathy, have already been evaluated and proven not to work. And CAVM proponents themselves often claim scientific evaluation is unnecessary or inappropriate for their methods. Is it really appropriate for a vet to maintain their license, their legal monopoly to practice veterinary medicine, by study things that are inherently unfalsifiable or incompatible with science or that have already been proven false?

The core issue is that the ethos of the CAVM community views scientific evidence as, at most, a nice extra to add on after one has already figured things out by trial and error and, at worst, completely irrelevant to the evaluation of the treatments we use on our patients. This is not just a disagreement about the evidence for specific practices, but an attempt to fundamentally alter the epistemological foundations of veterinary medicine.

 

 

Posted in General | 4 Comments

SH#$ Homeopaths Say

I have provided many examples over the years of the ridiculous and dangerous things veterinarians practicing homeopathy say. The fact that such individuals are allowed to practice this form of witchcraft as if it were a legitimate medical approach, and that they are protected under the legal monopoly licensed veterinarians have to practice veterinary medicine, is an embarrassment to the profession and a disservice to animal owners.

I recently ran across yet another example of the amazing ability of homeopathic vets to blame anything they don’t understand on vaccines or conventional veterinary medicine without the slightest supporting evidence or even plausible logic. Courtesy of Dr. Michael Dym:

Just to explain to animal guardians the difference from a holistic/homeopathic perspective on chronic vaccinosis, vs a more conventional perspective, where such information is not taught, and where reactions are only seen as occurring rarely within minutes or hours of a vaccination.

The “information that is not taught” is, of course, the completely unproven and unlikely information homeopaths believe about vaccines. There is no reason, or even excuse, for teaching such nonsense to veterinary students.

A 16.5 year old presented today after a sudden onset of what sounded like what is known as a neuroembolic event; the kitty presented with a sudden onset of hind leg stiffness/weakness, with staring behind him like something was there that was not. The kitty has been diabetic for many years. Most recent vet exam was back in first week of December 2015 where guardian had been concerned about odor coming from the cat’s mouth. He had not been to vet in a few years prior to that visit. That day, the kitty was given a rabies vaccination, and had its teeth cleaned on the same day. On careful review of the notes, it was noted that the kitty had an unsteady weakness and wobbliness for 3 days after the December visit, prompting a phone call of concern by the guardian, before “supposedly” normalizing back to prior status. However today’s sudden embolic, unexplained event, would be potentially seen as a chronic complication from the rabies vaccination from the prior visit in December.

“Would be potentially seen” actually means “homeopaths believe vaccines are responsible for any bad thing they don’t understand.” There is no evidence or sound pathophysiologic reasoning connecting these symptoms to the vaccine that was given. There are many potential explanations, and without detailed information and a good physical examination, I can’t diagnose the patient (unlike Dr. Dym, who apparently requires neither). However, blaming them on the rabies vaccination is not more reasonable than blaming them on the position of the planets at the time of the animal’s birth. Both explanations are purely arbitrary and faith-based.

These clinical situations, which typically go under the radar when assessing chronic immune or neurological effects from a conventional perspective, are far more common than is typical recognized by the conventional veterinary community, however, there is enough clinical evidence and even studies that do show the potential chronic effects on the brain and nervous system in pets vaccinated, especially with rabies, and when in a a [sic] geriatric or immune compromised state.

No such evidence exists, apart from “case reports” such as this by homeopaths making stuff up. Chronic medical problems associated with vaccination such as Dr. Dym describes could possibly occur, but these haven’t been detected or proven, simply assumed to happen because they fit the anti-science belief system of homeopathy.

Many disease conditions are considered miasmatic in animals. Niasms [sic] refer to inherent defects or inherent tendencies towards disease which can be genetically endowed. These underlying predispositions towards disease are often expressed after excessive vaccination or suppressive long term allopathic treatment. Our pets are clearly abused by allopathic overtreatment, with antibiotics corticDsteroiUs, and hormones. Vaccinations are given much Coo [sic] frequently, in excessive combination with one another. and without regard to need or potential exposure of the animal to these disease agents.

A fascinating combination of mischaracterization and outright falsehoods about conventional medicine with imaginary explanations for disease that come straight out of the 18th century. Homeopaths are perversely proud of having learned nothing about biology or the basis of health and disease since their founding father established the discipline over 150 years ago. And while they object strongly to any criticism of their methods, they feel perfectly comfortable announcing that pets are “clearly abused” by scientific medicine. ….vaccination can result in certain sensitive in­dividuals a chronic disease state one that is long-lasting, indeed in some cases a life-long condition. In human children there is increasing evidence of linkage between vac­cination and chronic illnesses such as autism, juvenile diabetes, and asthma.

Actually, there is increasing evidence, consistent across many years and millions of children, that these are not caused by vaccination. These false and dangerous belief actually injure and kill children when their parents are inappropriately frightened into avoiding appropriate vaccination.

This state of “vaccinosis” is under­stood as the disturbance of the life force that results in mental, emotional and physical changes induced by the laboratory modification of a viral disease to make a vaccina­tion. In other words, instead of seeing acute expressions of viral disease, we are, instead seeing symptoms of chronic ill­ness which are actually documented to occur in rabid animals. Symptoms of rabies includes Restlessness; viciousness; avoid­ance of company; unusual affection; desire to travel; inability to be restrained; self biting; strange cries and course howls; inability to swallow resulting in gagging whom eating/drinking; staring eyes; swallows wood ,stones, in-edibles; destruction of blankets, clothing; convulsive seizures; throat spasms; increased sexual desires; disturbed heart function; excited and jerky breathing. My biggest con­cern with pets are the changes in behavior after being vaccinated. This is usually along the limes of aggression, ‘`suspicion, unusual fears, etc.

The key words here are “life force.” Homeopathy is effectively a religion, not a system of medicine, and it relies on unprovable assumptions about the spiritual world to explain disease and how homeopathy is supposed to work.

It also relies on a simplistic idea about cause and effect that is often referred to as “sympathetic magic.” Superficial resemblances are assumed, without evidence, to represent deep functional connections.  Any symptoms that one could conceivably associate with rabies and that occur in any animal ever vaccinated for rabies are attributed to the vaccine.

However, even this slim thread of logic is abandoned in order to blame virtually any abnormality or problem on vaccination.

The essential aspect [of vaccinosis] is a lack of control of impulses. Many pets may exhibit any or many of the above behaviors indefinitely such as “reverse sneezing” and increased mounting seen in neutered pets. Conventional medicine does not explain these odd symptoms, but homeopathically these pets may be exhibiting symptoms of rabies vaccinosis and occur fairly commonly in my opinion.

There is no evidence or plausible rationale connecting “reverse sneezing” or mounting behavior with rabies vaccination, we are simply expected to take homeopaths’ word for the relationship and distrust a vaccine which has saved literally millions of human and animal lives.

It is a sad comment on how veterinary medicine is regulated that such nonsense is permissible under color of practicing veterinary medicine. And it is a sad comment on our profession that so few veterinarians are willing to openly challenge such baseless claims and fear mongering and acknowledge the overwhelming evidence that homeopathy is a worthless superstition, not a legitimate healthcare practice.

Posted in Homeopathy | 8 Comments

Skeptvet’s Acupuncture Adventure- Part 7: Emerging Themes

I haven’t updated my acupuncture adventure in a while, largely because I’m past the part of the course making general claims and justifications of acupuncture and into the portion that consists mostly of memorizing individual points and associated anatomical and functional elements. The details don’t matter a great deal if the general principles and the evidence related to them don’t hold up, and I remain unconvinced on that count. I appreciate the absence of mystical explanations concerning energy fields and extensive empty metaphors about Heat, Wind, Yin/Yang, and so on. However, the themes that are emerging in place of these concepts still seem quite problematic. I thought I would summarize some of the major principles being expounded in this course, and my concerns about them.

  1. Evidence of anatomical connection is taken as evidence of functional connection.

The instructors seem to feel that if any sort of physical connection can be traced between an acupuncture point and some other part of the body, it is fair to assume that stimulation at that point should influence that part. For example, if a point on a limb has sympathetic innervation that can be traced back to sympathetic nervous system (SNS) centers in the brain, it is assumed stimulation of that point can influence SNS.

There are several problems with this assumption. To begin with, as I discussed earlier, one can stick a needle almost anywhere on the body and find a nerve, muscle, blood vessel, or some other organ that it is claimed responds to needle stimulation. There is little evidence to suggest the particular points identified in traditional acupuncture, and still used in supposedly scientific acupuncture, are anatomically or functionally special. The assumption that they are underlies all the use of these, but the case for that assumption is weak and contradicted by abundant research showing that needling location makes little if any difference in the response to needling.

The other problem with the idea that because one can trace a nerve or blood vessel at one location back to other parts of the nervous or circulatory system one can manipulate the distant structures by needling this point is similar. In the body, everything is connected to everything else. There is almost no part of the body that can’t be connected in some way to any other part. Without showing that particular points used to cause specific effects, such as modulation of the SNS, have unique or specific connections that should cause those effects which other points don’t have, you are just arbitrarily identifying some locations as more special or connected than others in a way that isn’t evidence-based.

2. Any stimulus provided is assumed to result in the desired effect.

There seems to be another unproven assumption that when one stimulates a point believed to have special influence over some body organ or system that the stimulation will result only in the desired effect. Again as an example, if you needle a point that influences the SNS, it is assumed the influence will be what you want for the patient, increasing or decreasing SNS activity as desired. The main evidence for this seems to be the historical use of particular points for particular purposes. But if you can stimulate the SNS by needling a given muscle point, why isn’t it just as likely to cause undesired change? If point X downregulates SNS and point Y upregulates the parasympathetic nervous system (PNS), why couldn’t it be the other way around?

While the instructors acknowledge that acupuncture can have negative effects, these are mostly described as errors in needling, such as puncturing blood vessels, internal organs, or other structures one does not intend to puncture. It is also acknowledged that the needling itself can be painful. But the idea that correctly stimulating a particular point could have effects other than those desired has not, so far, been mentioned. This implies only beneficial effects with no side effects, which violates McKenzie’s Law.

3. Myofascial trigger point theory.

Dr. Robinson is an osteopath as well as a veterinarian, and a common element of osteopathic training is myofascial trigger point theory. This is the theory that pain and dysfunction, both locally and at distant parts of the body, can be caused by “knots” or “taut bands” of tension in muscles, which one can relieve by manipulation of these trigger points with massage, laser therapy, and needling. Dr. Robinson seems to suggest in her course that perhaps the most important way to identify which acupuncture points to treat in a given patient is to look for these trigger points and focus on relieving them locally, as well as treating the patient’s problem through other effects of acupuncture at points elsewhere on the body.

The problem is that trigger point theory is itself not much better supported by scientific evidence than acupuncture. It is widely believed and utilized among osteopaths, massage therapists, chiropractors, physical therapists, and others in both conventional and alternative medicine who treat musculoskeletal problems, but there is plenty of controversy and not a robust body of evidence to show the theory is correct or the effects of manipulative treatments occur through trigger point release. So it isn’t helpful to explain the unproven benefits of acupuncture using a similarly unproven, though somewhat more widely accepted, theory.

4. Vague terms with little specific evidence for their meaning

There is a lot of use of scientific and general terminology in ways that are not always defined very specifically and which seems to cover up the lack of evidence for implied clinical effects. For example, many purported effects of acupuncture are explained in terms of “neuromodulation.” I discussed this briefly earlier in the course, and the explanation or evidence presented for this concept hasn’t gotten a lot more detailed. Again, the assumption seems to be that if a point is connected to part of the nervous system then stimulation of that point will have desirable effects on that part of the nervous system. Calling this “neuromodulation” doesn’t explain or prove it to be true.

Similar problems pertain to other terms like “stimulating,” “releasing,” and so on. These may be descriptions of real actions and effects, but often they seem not to have very specific meaning or much evidence behind them.

Ultimately, I think Dr. Robinson and the other instructors are sincere in their belief that acupuncture can and should be scientific in its principles and validation. However, I also think they tend, as we all do, to interpret the limited and ambiguous evidence in ways that support beliefs they hold primarily based on clinical experience and habit. The tendency to gloss over evidence that contradicts our experiences and beliefs and to put the best possible face on evidence that supports them, even when it is weak, is universal. Unfortunately, even with the best intentions, that phenomenon can leave us with a firm commitment to our beliefs without a sound, scientific basis for them.

Posted in Acupuncture | 6 Comments

It’s the Law

mckenzie's law

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Another Study Shows Acupuncture is a Placebo Treatment

One consistent theme in acupuncture research is that it has proven very difficult to show any difference between the effects of acupuncture intended to treat a symptom or disease and the effects of various kinds of fake or sham acupuncture intended as a placebo control. Often, pretending to do acupuncture (inserting needles at places not thought to be acupuncture points or just pretending to insert needles) has as much of an apparent effect as “real” acupuncture treatment. (e.g. 1, 2, 3). The evidence also strongly suggests that where one places the needles during acupuncture treatment is largely irrelevant since the effect, such as it is, will be the same.

The most reasonable interpretation of this evidence is that acupuncture functions primarily a s a placebo. It is the therapeutic ritual, and possibly some small, non-specific counterirritant effects, that influence the patient. This means that all the theorizing about points and channels and both Chinese Medicine explanations of acupuncture (Five Elements, Yin/Yang, Qi, etc.) and conventional scientific attempts to explain it (endorphins, nerve stimulation, etc.) are just rationalizations for placebo effects.

The strength of this conclusion is, as always in science, proportional to the strength of the evidence. One more small piece of evidence has recently been released that supports this understanding of acupuncture.

Carolyn Ee, MBBS; Charlie Xue, PhD; Patty Chondros, PhD; Stephen P. Myers, PhD; Simon D. French, PhD; Helena Teede, PhD; and Marie Pirotta, PhD. Acupuncture for Menopausal Hot Flashes: A Randomized Trial. Ann Intern Med. Published online 19 January 2016.

This study randomly assigned 327 women with menopausal hot flashes to either acupuncture as guided by TCM principles or fake acupuncture with non-inserted needles. The bottom line was that both groups improved about 40%, but there was no difference between targeted acupuncture treatment and fake acupuncture. This is exactly what one would expect for a placebo therapy, ,and it is consistent with the growing body of evidence indication acupuncture is no more than a placebo for most uses.

 

 

 

Posted in Acupuncture | 4 Comments

What’s the Right “Dose” of a Vaccine for Small-Breed Dogs?

There’s a common misconception out there about vaccines that small animals should have lower “doses” of a vaccine than larger animals. This is a natural assumption stemming, most likely, from our familiarity with how medicines are dosed. However, while there are some differences in the amount of a vaccine given in different species, it is far less of a difference than would be expected if vaccines worked like drugs.

An analogy I often use to explain this is that drugs work like a dimmer switch for a lamp. You get some light with a small movement of the switch. The farther you push the switch, the brighter the light gets. There is a minimum movement below which the light stays off and a maximum above which the light won’t get any brighter. In between, however, the amount of light is proportional to the amount you move the switch. This is much like a drug, which often will have more effects the larger the dose given (though, of course, the reality is much more complicated since different drugs work in different ways, and in the real world pharmacokinetics and pharmacodynamics are highly complex and variable).

Since the dose of the drug is really the concentration in the blood or tissues, the larger an animal, the more drug has to be given to get the same amount in each milliliter of blood or each gram of body tissue. Assuming the simplest kind of drug dosing relationship, the size of the animal is directly proportional to the dose needed, meaning a dog that is 10kg will need twice as much drug as a dog that weighs 5kg. Again, reality is much more complicated, but as a basic starting point, we often dose drugs in milligrams per kilogram of body weight to reflect this kind of relationship.

However, vaccines don’t work this way. A better analogy for vaccines is a traditional light switch rather than a dimmer switch. There is a critical point at which the light goes from all off to all on. Movement below the threshold yields no light, and additional movement above the threshold gives no more light. For vaccines, there is a minimum immunizing dose (MID), a threshold at which the immune response is fully stimulated. Vaccines don’t work by being distributed throughout the body at a certain concentration, like drugs, but by triggering an essentially all-or-nothing immune response through interacting with special cells in the immune system.

The MID does vary a little by size, but not much. A horse, for example, will get complete protection form rabies after receiving only about twice as much vaccine as a dog, though the dog may be much less than half the size of the horse.

The same logic applies to any adverse effects from drugs and vaccines. In general, harmful effects get worse as the tissue or blood concentration of a drug goes up, which is very closely related to the dose given. With vaccines, adverse effects are unpredictable and not clearly related to dose. It is true that smaller dogs are more prone to allergic reactions to vaccines than larger breeds, but this likely has to do with genetic differences between breeds, not size. Smaller individuals within a breed have not been shown to be more prone to such reactions than larger individuals. The difference in size between members of the same species is almost never great enough to affect the MID, and the idea that a 10lb dog needs half the vaccine of a 50lb dog simply isn’t consistent with the biology of vaccines and the immune system.

Nevertheless, alternative medicine advocates frequently recommend smaller “doses” of vaccine for smaller dogs. There is not yet any real evidence to indicate that this would be an effective strategy to maintain immunity while reducing the risk of adverse effects. A recent “study” by Dr. Jean Dodds claims to provide some such evidence. However, this research has been supported by the American Holistic Veterinary Medical Foundation (AHVMF), and it bears many of the characteristic features of that group’s approach to research. As I’ve pointed out before, the AHVMF and associated groups and individuals seem to feel the purpose of scientific research is not to uncover the truth but to convince others of claims they already “know” are true based on personal experience or simple belief. Dr. Dodds herself has certainly shown this to be her approach before.

While Dr. Dodds’ study is only a pilot trial, and thus isn’t intended to prove anything, it is already being used as if it were evidence for giving smaller doses of vaccine to smaller dogs. The study has been published in the AHVMA journal, which is not accessible except to AHVMA members. From the information reported on her web site, it isn’t possible to evaluate completely what, if anything, we can reasonably conclude from it. But it is clear even from this limited information that the study does not provide a reason to change vaccination practices.

Thirteen dogs under 12lbs who had not been vaccinated in at least three years were enrolled in the study. Over a two-year period, antibody titers for distemper and parvovirus were taken for each dog at enrollment and then 4 months and 6 months after vaccination with a parvo/distemper vaccine. The vaccine was given as a “half dose,” though exactly what this means or how it was determined isn’t clear. The results reported were only that antibody levels went up in all of the dogs after vaccination and stayed higher than initial levels through the 6-month check.

This tells us almost nothing of relevance to the question of whether lower doses of vaccine can protect small dogs and reduce their risk of adverse events. Is the Hemopet titer a validated titer test with meaningful cutoff levels? What were the original titer levels? Were they already protective? How much did they increase, and would this make a difference between immunity and susceptibility? What vaccine history did the dogs have? Were any even susceptible to these diseases and, if so, would the vague half dose have protected them? Did any have adverse reactions? Had they had any adverse reactions to full-dose vaccination? Would they be less likely to have such reactions at the lower dose?

The unanswered questions are nearly endless, and many of them are crucial to the actual question. While a pilot trial, again, is only intended to test whether a real study is feasible and safe, the reality is that this trial is already being used to imply that giving less of a vaccine to smaller dogs is safer and just as effective as giving the intended dose. Dr. Dodds implies that on her site, and others reporting her results elsewhere do the same. Nothing about this trial justifies that claim.

Hopefully, more rigorous and transparent research will be done, but I am not optimistic. The goal is clearly to convince others of something Dr. Dodds and most of the AHVMA members already believe on faith, not to find out if this belief is actually true. As is often said about politicians, alternative medicine proponents often use science the way a drunk person uses a streetlamp: for support, not for illumination.

 

 

 

 

 

 

Posted in Vaccines | 13 Comments

Evidence Update: Pheromone Therapy for Stress in Cats

Back in 2010, I reported on a systematic review evaluating the use of pheromones to treat stress or other undesirable behaviors in cats and dogs. Of the 7 studies in cats and 7 in dogs that were of sufficient quality to be reviewed, no convincing benefit was seen in cats, and only one study showed a possible small effect in dogs. In another dog study published later that year, a few of the behaviors measured seemed to be affected by the pheromone, but there wasn’t any compelling evidence of a meaningful benefit. Now, another cat study has been published looking at the effect of a widely available pheromone product on physical and behavioral response to handling stress in cats both at home and in a veterinary hospital.

Conti, LMC. Champion, T. Guberman, UC. et al. Evaluation of environment and a feline facial pheromone analogue on physiologic and behavioral measures in cats. J of Feline Med and Surg. 2015. Epub before print.

This was a quite nicely done study in which 30 cats were evaluated at home and in a veterinary clinic for responses to pheromone (Feliway) or a placebo. Objective measures, such as heart rate, respiratory rate, blood pressure, and so on were taken, as well as more subjective measures, such as struggling. Cats were tested in response to routine handling at home and in the clinic after environmental treatment with either the pheromone or a placebo containing the vehicle (ethanol).

The results were pretty clear. While the clinic environment is generally more stressful than the home (reflected in differences in heart rate and respiratory rate), cats tolerate being handled and restrained in an unfamiliar environment better than in their own home (reflected in behavioral differences). In neither environment did the pheromone make any difference in the cats’ responses compared with placebo. The authors concluded that the pheromone had no influence on the markers of stress evaluated in this study.

Given the consistency of results across a number of studies, it is pretty clear at this point that pheromone products are unlikely to have any beneficial effects for dogs and cats.

Posted in General | 24 Comments

Make Medicine Better: Support Registration of All Trials in Veterinary and Human Medicine

Scientific research is the most powerful tool we have to discover and improve the therapies we offer our patients. However, research only helps us if the studies are well-conducted and the results are available for other researchers and clinicians to evaluate. As doctors, as owners of veterinary patients, and as patients ourselves, we need to know how medical research studies are conducted, and we need access to all the data they produce so that we can make effective and informed decisions.

Unfortunately, sometimes medical researchers make good plans for their studies but fail to follow through with them. And all too often research results, especially negative results showing a new treatment doesn’t work or has risks, aren’t published at all. This reduces the value of the research done; it wastes money and resources and places patients at risk.

One way to improve the quality of research and to make sure all the results are available is through clinical trial registries. When the plan for a research study is published in advance, it is more likely to be followed, and any weaknesses can be identified. And when government agencies, funding sources, and journals require advance registration and full publication of results, medical trials are of better quality and more vital information is available to the research community, doctors, and patients.

All Trials is an initiative to encourage registration and publication of results in human medical research. This initiative is having dramatic success. There has been significant progress in bring the pharmaceutical industry and other commercial research companies on board, as well as convincing government regulators, scientific journals, and organizations funding research to support registration. This initiative will make medicine research better and more transparent and will ultimately benefit both doctors and patients.

In veterinary medicine, clinical trial registration is almost non-existent. There are no registries available for most studies, and no mechanism to encourage or require advance registration. The evidence is clear that there are significant deficiencies in the quality and reporting of veterinary clinical trials, and the extent of negative publication bias is largely unknown. A system for clinical trials registration in veterinary medicine is even more critical than in human medical research.

Vet All Trials is a consortium working towards developing an effective veterinary clinical trial registry. Please consider learning more about the work of All Trials and the Veterinary All Trials Initiative and getting involved. Help make veterinary medicine better, for veterinarians, animal owners, and most of all veterinary patients.

You can go to our web sites to get more information and to sign the All Trials and Veterinary All Trials petitions.

Here is a short message you can share to raise awareness about this important issue.

 

Thank You!

 

Posted in Science-Based Veterinary Medicine | Leave a comment