John Maddox Prize for Promoting Science & Evidence in the Public Interest

A great science advocacy group from the UK called Sense About Science offers annual prize to recognize individuals who are publically promoting the importance and use of science and evidence. Here is how they describe the award:

2015 John Maddox Prize

The John Maddox Prize rewards an individual who has promoted sound science and evidence on a matter of public interest. Its emphasis is on those who have faced difficulty or hostility in doing so. Nominations of active researchers who have yet to receive recognition for their public-interest work are particularly welcomed.

The prize is open to nominations for any kind of public activity, including all forms of writing, speaking and public engagement, in any of the following areas:

Addressing misleading information about scientific or medical issues.

Bringing sound evidence to bear in a public or policy debate.

Helping people to make sense of a complex scientific issue.

Nominations can be made here. There are MANY great individuals out there working in this area, so pick your favorite and nominate them (even if it’s not a certain awesome veterinary blogger!) 😉

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In addition to my work on this blog, I do write for the professional veterinary literature and lay press as well, so I thought I’d list some of those publications for anyone who is interested.

Professional Literature

McKenzie, BA. Evidence-based veterinary medicine: What is it and why does it matter? Equine Vet Edu. 2014;26(9):451-452.

McKenzie, BA. Veterinary clinical decision-making: cognitive biases, external constraints, and strategies for improvement. J Amer Vet Med Assoc. 2014;244(3):271-276.

McKenzie, BA. Is complementary and alternative medicine compatible with evidence-based medicine? J Amer Vet Med Assoc. 2012;241(4):421-6.

McKenzie, BA. Evaluating the benefits and risks of neutering dogs and cats. CAB Reviews: Persp in Agricul, Vet Sci, Nutr, Nat Res. 2010;5(45).

McKenzie, BA. What’s the Evidence? Glucosamine and chondroitin for canine osteoarthritis. J Amer Vet Med Assoc. 2010;237(12):1382-3.

General Media

Evidence, Communication Key to Evaluating Veterinarian
SF Gate online: January, 2014

How Much Rawhide is too Much for Dogs?
SF Gate online: February, 2012

McKenzie, BA. (2012). Protecting public health is the responsibility of the government. In: Engdahl, S. (Ed.), Alternative Therapies (Current Controversies) (pp.130-7). Farmington Hills: Greenhaven Press. Adapted from “CAM and the Law, Part I: Introduction to the Issues,”, November 9, 2010.

McKenzie, BA. (2012). The popularity of alternative medicine is exaggerated. In: Zott, LM. (Ed.), Alternative Medicine (Opposing Viewpoints) (pp.90-7). Detroit: Greenhaven Press. Adapted from “How Popular is Acupuncture?”, March 25, 2011.

How to Help Elderly Dogs with Degenerative Conditions
San Jose Mercury News online: June, 2011

Why is my Cat Sneezing?
San Jose Mercury News online: April, 2011

Can Dry Cat Food Cause Kidney Problems?
San Jose Mercury News online: April, 2011

Don’t Pamper Pets with Halloween Candy
San Jose Mercury News online: November, 2010


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Science Through the Looking Glass- The Integrative Veterinary Care Journal

While much of so-called complementary and alternative medicine (CAM), also referred to by the latest marketing buzzword “integrative medicine,” is clearly inconsistent in theory and practice with science and science-based medicine, nevertheless practitioners of CAM like to assume the trappings of legitimate medical science. From copying the title of Doctor for professions like chiropractic, naturopathy, and “Oriental Medicine” which have little to do with science-based healthcare, to holding “scientific” conferences and conducting research studies (sometimes legitimate, often pure propaganda), proponents of CAM try to look as much like practitioners of science-based healthcare as possible even while simultaneously denigrating it and claiming to have entirely different and superior methods. Another element to this effort is the publication of CAM-centered journals.

Legitimate research into plausible therapies, such as dietary supplements and herbal remedies, is often published in mainstream medical journals. But much of CAM research is so clearly ridiculous or so methodologically sloppy that it cannot be accepted into scientific journals. This has led to the creation of a parallel system of journals with all the trappings of real medical journals but willing to publish almost anything that makes CAM therapies look like they work.

In the past, I have written about articles appearing in some of these publications, including the Journal of the American Holistic Veterinary Medical Association journal of the Academy of Veterinary Homeopathy. I recently had an opportunity to look at the current issue of another example of this genre, the Integrative Veterinary Care Journal (IVC).

Despite the title, this is really more of a magazine than a journal, publishing opinion pieces and anecdotes primarily rather than formal research studies. It is also dense with advertising, some of which is cleverly formatted to look like articles rather than ads, apart from the small label of “Advertorial” or “Product Profile” in the header. Legitimate journals, of course, also employ sometimes excessive or ethically questionable use of advertising, but there is an added layer of hypocrisy in the blatant commercialism of the IVC given the tendency of CAM advocates to attack science-based medicine for financial ties to healthcare product industries. This reminds us that practitioners of alternative therapies have every bit as much financial interest in their products and services, and in the industries that support them, as conventional practitioners.

The Advisory Board for the IVC includes many familiar individuals associated with the AHVMA and other pro-CAVM organization. I have previously discussed statements made by Dr. Richard Palmquist (1, 2, 3, 4, 5) Dr. Jean Dodds (1, 2), Dr. Barbara Fougere (1), Dr. Joyce Harman (1) and Dr. Christina Chambreau (1), and all have staked out positions incompatible with a science-based approach to veterinary medicine. Dr. Steve Marsden is a well-known practitioner of so-called Traditional Chinese Veterinary Medicine (TCVM), which is a soundly mystical, pseudoscientific practice, and he is a driving force behind the Cured Cases database and forum, a project for collecting anecdotes to generate the impression of evidence in favor of alternative therapies and for providing a forum in which talking about disease being caused and treated by alterations of Heat, Wind, Ying, Yang, Chi and so on is taken seriously. So it is not surprising to find that the contents of the IVC reflect the disdain for the scientific approach to medicine these folks often express.

While there are certainly reports and ads for mainstream medical practices in the IVC, these are “integrated” with some pretty egregious pseudoscience and nonsense. No effort is made to distinguish legitimate science from outright magic. This illustrates a serious problem with the whole concept of integrative medicine. It gives the appearance of legitimacy to nonsense while degrading the overall quality of veterinary medicine. Or as Mark Crislip colorfully puts it, “If you integrate fantasy with reality, you do not instantiate reality. If you mix cow pie with apple pie, it does not make the cow pie taste better; it makes the apple pie worse.”

Essential Oils and Chinese Medicine
The first example of nonsense in this issue of IVC is an article discussing the use of essential oils according to the principles of Chinese Medicine. The article is written by Dr. Cynthia Lakenau, a “holistic” veterinarian, and Jeffrey Yuen, a Chinese Medicine practitioner. Dr. Lakenau practices the usual hodgepodge of mutually inconsistent methods which are unified only by their opposition to science-based medicine. She also has some of the usual uncharitable views of conventional veterinary medicine:

I am very encouraged by the acceptance in some corners of the conventional world, enough to truly hope and believe that every veterinary college in the future will offer training in all alternative modalities, minimize drug use, and truly practice wellness maintenance medicine.  But I see two problems both created from greed.  I am nervous that when the conventional world realizes the loss of income from animals being truly healthy, they might wage an aggressive smear campaign. [I imagine that is how she’ll categorize this article if she sees it]

Mr. Yuen has no conventional medical training but describes his credentials this way:

Jeffrey C. Yuen comes from two Daoist lineages. He is an 88th generation Daoist master of the Yu Qing Huang Lao Pai (Jade Purity Yellow Emperor Lao Zi School) and a 26th generation Daoist Master of the Quan Zhen Long men Pai (Complete Reality Dragon Gate School)… Having a strong resonance with Daoist teachings ever since childhood, Jeffrey studied extensively under Master Yu Wen and was allowed to openly practice and serve the community when he was 16 years old… Mr. Jeffrey C. Yuen also studied Chinese herbal medicine with Master Gong Song-Liu, a eunuch for the last two emperors of the Qing Dynasty who apprenticed with the imperial medical physicians. As a friend of Master Yu Wen, Gong was persuaded to teach Jeffrey, imparting his deep knowledge of Chinese medicine over a period of 8 years. ..Today Jeffrey Yuen is recognized internationally as a master scholar, teacher and practitioner of Classical Chinese Medicine. This includes Acupuncture, Herbal Medicine, Nutrition/Dietetics, the therapeutic use of Stones and Essential Oils, Tai Qi, Qi Gong and Daoism. Indeed, as a Daoist priest, Jeffrey is at the forefront of the restoration of the spiritual roots of Chinese Medicine. His teachings rooted in the spiritual tradition of Daoist mysticism bring a clarity, wisdom and depth to Chinese Medicine rarely found today.

This resume illustrates the explicitly religious nature of TCM and TCVM. The health practices employed in TCM are fundamentally spiritual practices based in a faith-based ideology, not medical practices aimed at curing physical ills or based on modern scientific principles. Despite the use of herbal remedies and the recent adoption of acupuncture among mainstream medical professionals, at its core TCM has more in common with Christian Science, Voudou, and other forms of faith healing than it has with scientific medicine. Sadly, it is often presented to patients and veterinary clients as a medical rather than a religious practice.

The mystical nature of this approach is evidence in the IVC article concerning essential oils.

Essential oils represent the genetic unfolding of the plant, the Jing, the essence of the plant. They therefore have potential effects on physical developmental problems as well as the mental and spiritual…The plant’s Jing will resonate with the body’s Jing. As a result, a vast degree of possible healing can occur when essential oils are applied to acupuncture meridians..

The article goes on to suggest that if children and animals fear needles or do not willingly ingest Chinese herbal concoctions, one can achieve similar effects by applying essential oils to magic locations on the body (despite the problem that acupuncture points cannot be shown to exist or be consistently identified and agreed upon by acupuncturists).

And while it is claimed that scientific sounding rationales for the use of such oils can be found (what the authors call “the chemotype theory”), this is not considered essential to evaluating the safety or efficacy of such products. Instead, TCM categorizes these agents in term of the mystical system it employs for other interventions, “law of signatures, five elemental associations, nature or temperature, taste, aroma, relationship to neighboring plants and channel (or meridian) affiliation.” This collection of mystical theoretical constructs, and the associated diagnostic practices employed in TCM, renders even potentially plausible interventions like herbal medicine unreliable when they are employed according to what is essentially a system of magic.

Additionally, according to Lakenau and Yuen, essential oils are categorized and employed according to their “notes.”

High Notes- Oils that evaporate rapidly, influence the Wei Qi (defensive immune system or external) level, Primarily used for acute conditions. “They awaken the senses, serving as the first invitation for a patient to change.”

Middle Notes- “used for more sub-acute problems that tend to be in the Ying level, which affects plasma in the blood…useful for circulatory issues (movement of Qi moving blood), to regulate digestion…and for cognitive function (digesting and assimilating the information around us and eliminating that which is not needed” [which, presumably, includes biochemistry, physiology, and clinical trials]

Base Notes- “for chronic, constitutional issues at eh Yuan level (which can influence genetic tendencies)”

While the theory here is fanciful, the fact that it is suggested employing these remedies in this manner is actually a responsible way to treat serious disease is outrageous.

…if you have a dog with an autoimmune joint disease such a rheumatoid arthritis, you could use a top note…to help with his ability to rest during any acute situations; a middle note…to help clear the heat of the latent infection; and a base note…to help treat the fascial pain

Since rheumatoid arthritis is a serious, painful disease which is not due to the “heat of a latent infection” and does not involve the fascia, following this advice would be gross malpractice.

Finally, the authors suggest topical application of essential oils for “bodywork and cranial-sacral work,” thus merging the theoretical nonsense of certain manipulative therapies with the nonsense of TCM. They also suggest deciding where to apply the oils based on acupuncture points (which are, of course, as objectively real as constellations in the night sky) or which “humors” you want to affect. Apparently, the ears affect the nervous system whereas the paws effect circulation. At this point, I suspect no one will be shocked to learn that no scientific research is cited to support any of the claims or recommendations in this article.

Treating Canine Lipomas
Another article in this issue addresses the treatment of a common benign tumor called a lipoma. These are aggregations of fat which typically occur in middle-aged and older dogs. The exact cause is not known. They are more common in certain breeds and possibly in overweight dogs. Research in humans suggests possible genetic risk factors, but the definitive cause is not known. This, of course, provides an open field for rampant speculation of how to treat and prevent these benign tumors.

Conventional medicine recommends no treatment unless they cause clinically important problems, based on size and location, and then surgical removal. However, the author of this article, Dr. Christina Chambreau, who is predominantly a homeopath (meaning, she believes in magic) has a different perspective.

The holistic perspective looks at all symptoms as clues to an underlying vibrational imbalance (Qi, vital force, etc.). Most integrative practitioners see lipomas as the body’s way of exteriorizing toxins…TCVM lists lipomas as stagnation of body fluids.

This paragraph manages, completely without irony, to lump together a variety of mutually incompatible theories that share only the feature of being nonsense incompatible with actual science. Qi, vital force, etc. (by which she means other alternative medicine constructs such as chiropractic’s “innate intelligence,” Ayurveda’s “prana,” and so on) are mystical forces that are fundamentally spiritual in nature. These are undetectable, unmeasurable, magical energies that apparent cause all disease and can be manipulated to cure disease, but only if you are willing to believe in them with no actual evidence. Once again, this illustrates the fundamentally religious nature of much alternative medicine.

The notion that disease is caused by mysterious, unidentified “toxins” is another popular alternative medicine trope. It is theoretically inconsistent with the notion of spiritual imbalances causing disease, but this never seems to bother alternative practitioners. In any case, it shares at least the quality of being arrant nonsense.

Stagnation of body fluids is a reference to the humoral theory of health and disease. This is a popular concept in pre-scientific folk medicine. It was the basis for all the bloodletting and purging that European and early North American physicians used to practice, but these ideas and associated practices were abandoned by conventional medicine when science proved them to be untrue an ineffective. TCVM and other holdovers from pre-scientific medical practice retain such notions despite the evidence against them and the dramatic improvement in health that accompanies abandoning these ideas.

Of course, the fantastical theories are merely a way of introducing equally fantastical treatments that are equally lacking in any evidence of efficacy other than the testimony of the faithful. Though Dr. Chambreau admits that most integrative practitioners report being able to predictably cure lipomas with their therapies, she nevertheless uses anecdotes of responses to treatment as the basis for recommending specific therapies. Of course, she recommends minimizing the use of “chemicals and drugs in medical treatment” and of flea and tick preventatives. There is no evidence that these are risk factors for lipomas, of course, but Dr. Chambreau is willing to overlook this lack of evidence of causality, as well as the evidence of beneficial effects from medicines and parasite prevention, in order to imply that avoiding these substances will somehow reduce the risk of lipomas. Why work to prove something you can simply imply without evidence?

She also suggests looking out for her Early Warning Signs of Internal Imbalances, a dog’s breakfast of random clinical findings that she suggests, again without evidence, are somehow related to mysterious “imbalances” that might lead to actual disease. To this she adds the suggestion that some alternative vets believe lipoma risk can be reduced by “natural rearing,” a philosophy I’ve discussed before which is consists of an irrational hodgepodge of unproven or quack practices. And, not surprisingly, raw foods are mentioned as possibly preventing lipomas, just one among the many miraculous, and as yet unproven, claims for raw diets.

Speaking of miracles, Dr. Chambreau discussed one treatment for lipomas that really can’t be characterized in any other way. She reports the case of a dog who somehow managed to get lipomas despite “being raised naturally with few to no vaccines, a great diet, and no chemical exposure.” (Not that this casts any doubt, of course, on the value of these preventative strategies). He was treated with “Tui Na…Chinese massage to enhance Qi and lymph flow…[using] acupressure points on the meridians above and below each lump.” And as we all know, “Pericardium 8 is a spot in the center of a person’s hand that emits a significant amount of chi, so [the acupressure practitioners] held their palms on the lipoma. The lumps would resolve within a few days…” So by literally laying on of hands, we can supposedly make lipomas go away using the chi we project from a point in our palms named after the sack around the heart? Amazing!

Apparently, as the dog aged, this magic ritual didn’t entirely make the lumps go away anymore, but Dr. Chambreau confidently reports that “they were much less problematic than they would have been if not treated.”

The article goes on to suggest that some lipomas have been shrunk or cured using acupuncture, Chinese herbs, “a high fiber macrobiotic diet,” homeopathy, colostrum, flower bud therapy, probiotics, and chiropractic. No evidence other than anecdotes is provided for any of these claims. She does also mention liposuction, steroid injections, and surgery, all of which actually do have scientific research evaluating their effects.

With regard to surgery, however, Dr. Chambreau suggests that the most common and clearly effective treatment for lipomas is actually a bad idea, and buttresses this claim with a mishmash of sloppy reasoning and mystical ideology:

Several surgeons stated that removing one lump resulted in multiple lumps appearing later in the dog’s life. [And we know the surgery is the cause of the subsequent tumors how?]

This is because surgery removes only the tip of the iceberg. Surgery will do nothing to address the toxins causing the fatty tumor, and will leave scar tissue behind; this blocks the point of discharge the body needs to release those toxins. Once scar tissue is created, the toxins feeding the tumor are forced deeper into the patient’s body, causing damage to deeper organ systems. [A frightening prospect made less disturbing by the fact that it’s completely made up and that these “toxins” have not been shown to actually exist or cause any of the terrible consequences Dr. Chambreau proposes]

Reiki for Shelter Animals
Reiki is another form of spiritual healing in which a healer directs a mysterious form of spiritual “energy” to heal physical disease. It has the advantage over some alternative therapies of being benign in itself since it relies on magic rather than plant chemicals or needles. Nevertheless, no reliable scientific evidence has demonstrated any actual healing effects. If magic is real, then perhaps someday we will be able to demonstrate such effects, but as Tim Minchin has pointed out, “Throughout history, every mystery ever solved has turned out to be—not magic.”

The process of performing Reiki, however, might have some actual behavioral and physical effects on animals. It does, after all, involve quiet, gentle interaction and sometimes touch from a human. Anyone who has ever shared a bed or petted a dog or cat will be unsurprised by the idea that animals might enjoy this sort of interaction and find it comforting. It seems gratuitous to take ordinary kind and comforting interaction that might help shelter animals and load it down with a pile of mystical baggage and then claim that is why the animals benefit.

In this issue of IVC, however, Ms. Kathleen Prasad makes some pretty dramatic claims for Reiki in shelter animals, some of which may be actual effects of the interaction (though claiming this would require controlled research) and others are farfetched at best.

Despondent cats and dogs become more social and seem happier

I wouldn’t be at all surprised if this is true. I just would like to see some evidence it has anything to do with “spiritual energy” instead of loving human contact.

Sick animals are aided in their recovery

This kind of claim needs to be proved to be taken seriously

…Animals who have been here for a long time often get adopted shortly after treatments…One of the amazing benefits of Reiki is the inner transformation it creates in these animals..[who] can release their stress and get back in touch with their true essence. Once they remember who they are, their sweet spirits can shine through so potential adopters can see…

Clearly, these folks haven’t heard of confirmation bias or any of the other ways we fool ourselves into thinking our actions have effects they really don’t. While gentle human interaction may indeed relieve stress, all of this spiritual and psychological language is merely the projection of humans’ feelings and beliefs onto animals. And the idea that there is a direct relationship between being treated with Reiki and getting adopted is an empirical claim which needs to be demonstrated before being made.

[Some Reiki believers] often speak of how Reiki transforms the hospice experience…Since learning Reiki and using it to help with animal care during hospice, [they] report that all the deaths they have witnessed are extremely peaceful.

The use of spiritual practices in animal hospice care is something I have written about before, and it does come with significant risks. While the humans involved may find such practices comforting, and that is a good thing, there is no reason to think our animals share any of our many specific and often incompatible spiritual beliefs. I have personally seen animals who are suffering be denied appropriate pain control and human euthanasia by owners whose spiritual beliefs precluded the use of these therapies. While animal owners are entitled to these beliefs, veterinarians have a duty to advocate for the welfare and interests of our patients. It is all too easy for psychologically comforting rituals like Reiki, acupuncture, homeopathy, and so on to fool us into thinking we have done something real to reduce an animal’s suffering when we actually have not. We must rely on objective scientific evidence to help us determine if what we are doing is truly comforting our patients and not just us.

The article also claims that Reiki can help people working with shelter animals cope with stress. Again, I suspect this is true. People are often surprised to learn that I meditate and find it helpful personally. That is quite a different thing, however, from claiming that one can channel a spiritual energy force to improve physical health and the chances of a pet being adopted!

Evidence-based Chinese Herbs for Horses?
Dr. Kendra Pope contributed an article to this issue of IVC which makes use of a popular buzzword in both conventional and alternative veterinary medicine, “evidence-based.” I have been deeply involved in the promotion of evidence-based veterinary medicine (EBVM) for years, and unfortunately I often find that when people use the term I am reminded of the movie the words of Inigo Montoya in the move The Princess Bride, “You keep using that word. I do not think it means what you think it means.”

Evidence-based medicine is a set of principles and practices that extend the basic epistemological principles and methods of science to the development and use of scientific knowledge in medicine. It involves explicit and structured incorporation of scientific research evidence into clinical practice. Merely citing case reports or methodologically weak and biased studies in support of your claims and announcing “QED!” is not evidence-based medicine.

In this article, a number of citations are made in support of specific claims. These include the claims that acupuncture can effectively treat lameness and that a variety of Chinese herbal remedies, presumably applied according to the mystical system of TCM, can effectively treat tendonitis, acute and chronic respiratory disease, chronic sinusitis, colic, seizures, infertility, hepatitis, fibrous osteodystrophy, and other maladies. Since published literature is cited to support these claims, it is tempting to simply assume they have been proven and accept them at face value.

This ignores, however, the critical element of known as critical appraisal, the explicit evaluation of published research to determine the degree of confidence it is appropriate to have in the conclusions of research studies and their applicability to particular patients. A closer look at the citations in this article revealed some interesting facts. For one thing, of the 27 publications cited, 24 were in journals or textbooks devoted exclusively to TCM or alternative therapies. Of the remaining 3 articles, two were narrative reviews (essentially individual opinion pieces), and only one was a report of a clinical research study. And guess what this one study found? “Treatment with the composite did not result in statistically significant changes in any of the parameters evaluated.” That’s right! The only study cited that wasn’t from an alternative medicine journal found the remedy didn’t work! Yet it was cited in support of this practice. How’s that for evidence-based medicine?

The bulk of the studies come from the American Journal of Traditional Chinese Veterinary Medicine, and when reviewed most of these are either narrative reviews and opinion pieces, case reports and case series, or uncontrolled trials at high risk of bias. This is typical of the reports in journals dedicated to alternative veterinary therapies. They create the impression of real science by borrowing the terminology and some methodological features of scientific research but ignore the fundamental principles and key controls for bias and error that make science and science-based medicine work. This is part of the reason why a recent systematic review of veterinary homeopathy written by full-time advocates for the method was unable to find convincing evidence of real clinical effects despite many hundreds of published reports. The quality is nearly always so poor as to render the results unreliable.

Bottom Line
The IVC journal is a classic example of the effort of alternative medicine advocates to have their cake and eat it too. They want to have the legitimacy and the marketing value of being seen as scientific without giving up those beliefs and practices which are fundamentally incompatible with science. They want scientific evidence to support their beliefs but never see it as an adequate reason to abandon any therapy. And they want to be seen as open-minded doctors “integrating” alternative therapies into accepted conventional medical practice while at the same time portraying conventional medicine as frequently misguided, ineffective, dangerous, and subordinate to malign financial interests.

If CAVM proponents want scientific legitimacy, they should earn it through real, rigorous research published in real veterinary journals, and through a willingness to treat their methods as scientific hypotheses open to testing and even rejection rather than tents of an essentially religious faith that can be justly accepted without evidence on the basis of belief alone. Products like IVC are merely marketing masquerading as science, and this is fundamentally deceptive.
















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FDA Reviews Its Regulation of Homeopathy-Now is Your Chance to Comment!

The FDA is reviewing its regulation of homeopathic products, both prescription and over-the-counter. The current regulatory structure essentially no evidence of safety or efficacy since the products were grandfathered into the legislation in 1938 by its author, a Senator who had practiced homeopathy . The FDA considers homeopathic remedies for animals to be unapproved drugs but has generally declined to enforce regulations concerning their veterinary use.

Despite this regulatory loophole, the FDA does not recognize homeopathic drugs as effective, and states on its website, “FDA is not aware of scientific evidence to support homeopathy as effective.” The evidence, which I have reviewed here many times, is overwhelmingly clear that homeopathy is nothing more than a placebo. (1, 2, 3, 4)

The FDA is asking for input from the public concerning this regulatory system. It will be holding a public hearing April 20 and 21 in Silver Spring, MD and also accepting written comments electronically and by post. I encourage anyone interested in seeing the regulation of these products rely on evidence rather than history and politics to consider attending or offering a comment.

I have submitted a comment, along with a document of supporting information. Anyone who wishes to post a similar comment is welcome to use any or all of this text for that purpose:

The Food and Drug Administration (FDA) Proposed Rule: Homeopathic Product Regulation: Evaluating the Food and Drug Administration’s Regulatory Framework After a Quarter-Century; Public Hearing

ID: FDA-2015-N-0540-0001

I wish to offer my perspective on the regulation of homeopathic remedies by the FDA. As both a healthcare consumer and as a practicing veterinarian, I see the marketing and use of homeopathic products without legitimate scientific evidence of safety and efficacy as a danger to human and animal health. These products should be held to the same standards of evidence as any other drug if they are to be marketed with claims that they can treat or prevent disease in humans or animals.

The current regulatory structure effectively allows most homeopathic products to be marketed and used in humans and animals, with or without the guidance of a physician or veterinarian, without any of the scientific evidence of safety and efficacy required of most drugs regulated by the agency. This is a result of historical and political factors, but it leaves the public without the scientific information and guidance needed to make effective and informed decisions about the use of these products. The FDA itself acknowledges that “FDA is not aware of scientific evidence to support homeopathy as effective.” (

Even National Center for Complementary and Alternative Medicine (NCCAM) of the National Institutes of Health, which is specifically charged with investigating alternative therapies, acknowledges the lack of scientific evidence for efficacy:

“Most rigorous clinical trials and systematic analyses of the research on homeopathy have concluded that there is little evidence to support homeopathy as an effective treatment for any specific condition.”

The scientific evidence is overwhelming and unequivocal that homeopathy provides no therapeutic benefit beyond the placebo effect of the consultation with a homeopath. Despite over 150 years of use and extensive research, no convincing evidence of a specific treatment effect has been produced. And there is also evidence that despite containing no active ingredients, homeopathic remedies can be harmful. When such products are mislabeled as homeopathic when they actual contain biologically active chemicals, or when they are used to treat serious illness in lieu of effective medical care, they can cause injury and death. Attached I have provided a brief overview of this robust scientific evidence concerning homeopathy.

The evidence that homeopathic remedies are ineffective is an internationally accepted scientific consensus rejected only by dedicated practitioners of homeopathy and those they have misled. Given this consensus, it is an abrogation of the FDA’s responsibility to protect human and animal health to allow therapeutic and prevention claims to be made for these products. I recommend the agency take the following steps.

  1. Draft and submit to Congress a report identifying homeopathy as ineffective and recommending changes in the agency’s authorizing legislation to prohibit the marketing and use of homeopathy without fulfillment of the same new drug licensing requirements applied conventional drugs.
  2. Produce educational materials for healthcare providers and patients in both human and animal health fields identifying the ineffective nature of homeopathy for the treatment or prevention of human and animal disease.
  3. Require all OTC homeopathic products to carry a label similar to that required for dietary supplements under DSHEA, “This/these statement(s) have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.”
  4. Vigorously enforce regulations in both human and animal health fields prohibiting treatment and prevention claims for homeopathic remedies without fulfillment of the requirements of a NDA.

Regulation of Homeopathy [Docket No. FDA–2015–N–0540] Supporting Evidence Document


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Evidence Update- Ocu-GLO for Prevention of Cataracts in Diabetic Dogs

About a year ago, I wrote a review of Ocu-GLO, an oral supplement marketed for a variety of purposes:

Ocu-GLO Rx™ is needed when your dog is showing any of the following signs:

– Diminished vision at night or in dim conditions – Diminished vision at all times – Cloudy appearance to eyes – Pupils that do not constrict – Obvious cataracts Or… -Your dog is generally healthy, but you want him or her to be placed on an excellent lifetime antioxidant supplement to help support and enhance ocular health and also general health.

We (Drs. Carmen Colitz and Terri McCalla) are also dispensing Ocu-GLO Rx™ for patients predisposed to primary glaucoma (having lost their first eye to glaucoma) and that already have glaucoma; for Golden Retrievers with pigmentary uveitis (also called “Golden Retriever Uveitis” or GRU); for diabetic dogs in which cataracts are immature or have not yet formed; for dogs with senile retinal degeneration; for dogs post-cataract surgery to help reduce the incidence of PCO and ACO (Posterior Capsular Opacity and Anterior Capsular Opacity) and for any dogs for which owners want to provide the best nutritional support for their pet’s eyes.

At the time, I concluded that the theoretical premise behind the product and the specific ingredients included was plausible but supported only by weak evidence, and there was little direct clinical research in humans, and virtually none in dogs, showing actual benefits. Therefore, no firm conclusion about the safety and efficacy of the product was possible.

I also noted that:

Unlike the marketing for many supplements pitched to pet owners, the claims made by this company are pretty measured and reasonable in light of the limited available evidence…Hopefully, the ophthalmologists behind the product will pursue appropriate research efforts to determine if, in fact, the product has the benefits they suspect and what, if any, risks are associated with its use.

I was pleased, therefore, to see a clinical trial investigating Ocu-GLO published this month which adds to the evidence regarding this product.

Williams, D. Fitchie, A. Colitz, C. An Oral Antioxidant Formulation Delaying and Potentially Reversing Canine Diabetic Cataract: A Placebo-controlled Double-masked Pilot Study. Int J Diabetes Clin Res 2015, 2:1

This trial targeted a specific disease, cataracts developed by diabetic dogs. The process of cataract formation in diabetics is well understood, and there is reason to expect at least some of the ingredients in Ocu-GLO might influence this process, so again there is a plausible potential mechanism here that is consistent with established science.

The study involved giving either the supplement or a control containing antioxidant vitamins but not several of the other ingredients in Ocu-GLO, to 15 dogs each and monitoring them for changes in their lenses that would indicate cataract formation. It was not considered ethical to allow actual cataract development, so once such signs appeared, the treatment was identified and dogs who had been getting the control vitamins were switched to the supplement.

The results were quite impressive.

Mean time without change in lens opacification at the time of writing was 278±184 days with Ocu-GLO Rx™ and 77 ± 40 days in the placebo group. Median duration without lens change was 261 and 84 days, respectively, this difference being statistically significant at p=0.0003.

Twelve of the 15 dogs (80%) taking the placebo developed significant lens changes while on the study protocol. Five of 15 dogs (33%) taking Ocu-GLO Rx™ developed significant cataract, in three of these animals Ocu-GLO Rx™ was not being given as directed…

These differences between the groups is not only statistically significant but, far more important, they are clinically relevant. While the supplement did not absolutely prevent lens changes in treated dogs, it appeared to dramatically delay these changes. In one subject who was switched from the control supplement to the test product, it appeared that the product even reversed changes that had already begun.

Like all research, there are flaws and limitations to this study which require some skepticism about even such dramatic results. To begin with, several key methodological factors were not mentioned in the published report. This is unfortunately extremely common in veterinary research. However, I contacted Dr. Williams, the lead author, and he was kind enough to answer a few questions and provide at least some of this missing information.

There is no mention in the paper of how the subjects were assigned to the two groups. Random assignment, and a process which prevent anyone from intentionally or unconsciously influencing the selection and assignment of patients, is a critical component to reducing bias and error in clinical trials. According to Dr. Williams, the subjects were individually randomized to the two groups. It is not entirely clear, though, how this process was protected from being unintentionally influenced by study personnel or how the exact balance in number between the groups was achieved.

Blinding of investigators and owners to the treatment assignment is another critical element of an effective clinical trial. It appears that investigators were effectively blinded to the treatment each patient received. This is especially important because the outcome being measured was subjective and not very precisely defined as “significant progression of lens opacity, as documented photographically.” It is not clear if the owners could distinguish the two treatments, but this would be less likely to have a significant impact on the results since owners were not involved in assessing the outcome.

A number of other potential limitations exist in this study, including minimal comparison of the two groups before treatment to ensure there were no relevant differences and a small number of subjects, but in general the design and execution seem quite good.

One of the authors, Dr. Colitz, is affiliated with the company marketing Ocu-GLO. This raises the potential of unconscious or overt bias, but this is likely mitigated by the blinding, randomization, and other typical bias-control aspects of the study. Dr. Williams also indicated that there was no financial support of the study from the manufacturer, reducing the risk of any funding bias.

The issue of adverse effects was not specifically addressed in the published report. The company has previously indicated that some unpublished data exist demonstrating the product is safe, and there is no specific evidence to suggest any risk, though unintended effects with long-term use or in particular patients cannot be completely ruled out. With the limited evidence currently available, there seems to be little risk to the use of this product.

I have previously discussed the Decline Effect, which is a well-recognized phenomenon in which small, early studies of a scientific hypothesis give dramatic results which diminish, and sometimes disappear entirely, in subsequent research with better control for bias, confounding, and other sources of error. So it is important to remember that no single study ever definitively proves or disproves a scientific hypothesis. As the researchers themselves acknowledge, further research is not only desirable but necessary to allow confidence in these findings and this treatment.

Bottom Line

This is a small but well-executed clinical trial with a large, clinically relevant difference in the progression of changes in the lens clarity of dogs with diabetes treated with Ocu-GLO compared with a control supplement. The trial is not perfect, of course, and no single trial should ever be viewed as definitive. And this study applies only to the issue of using this supplement to slow the development of cataracts in diabetic dogs. It does not provide good evidence that the supplement can completely prevent or cure cataracts or that it is effective for other uses.

As always in veterinary medicine, however, we must make decisions on the basis of the imperfect evidence we have, while still pursuing more and better evidence. Though the evidence is still limited at this point, I believe it is good enough to recommend the use of this supplement for cataract prevention in diabetic dogs.





Posted in Herbs and Supplements | 3 Comments

What Do Holistic Vets Say About Science and Evidence-based Medicine?

I’ve written several times about how proponents of alternative therapies appear to view science and evidence-based medicine. (1, 2, 3)  I think it is critical in evaluating these practices, as pet owners or  veterinarians, to understand the philosophy and approach behind them. Alternative medicine advocates will frequently talk about their respect for science, and will laud studies that appear to support their claims. But in many cases, they are fundamentally not convinced that science is superior to personal experience or faith as a method of evaluating medical therapies, and they are virtually never willing to abandon a practice they believe they have seen work no matter how clear the evidence against it is. If people wish to apply such practices, of course they are free to make that choice. But they should be fully and honestly informed when they are being asked to choose belief and opinion over science and evidence.

The following are comments veterinarians who are advocates for alternative veterinary therapies and critics of conventional medicine. These illustrate some of the views that should concern those of us committed to a scientific approach to evaluating the treatments we use for our patients and animal companions. I will be adding to this collection of comments over time, just to have examples available of the kinds of misconceptions those of us committed to a science-based approach to medicine need to address in our efforts to educate and to promote evidence-based medicine.

Evidence-based Medicine
“Remember evidence based science is last to know.”

“#AHVMF strongly supports scientific process, but in seeking real answers we recognize that scientific practice is last to know. #pioneers”

“Since evidence based medicine can’t know what hasn’t been studied, a false separation of proven vs unexamined data fields arises.”

“Evidence based medicine is being miss used according to its creators. It was about integrative informed decision processes.”

“The evidence said the case would die, the people felt otherwise. They tried, they lived, they danced together & finally all died. Life! :-)”

“Evidence should inform decision making but not limit treatment options. Combining experience and evidence is called evidence based practice, an excellent model for advancing veterinary care in areas with less evidence. Patients need access to all options and guardians and clinicians want to know.”

“At the root a healing from placebo IS real healing from the person. How do we improve self healing? Can we align w/ Nature simply powerfully.”

“Perhaps love is the basis of placebo. In that case let’s fill the world and to hell with the research. Ascendant mindfulness finds healing.”

“Stories have an important place in discovery of new approaches and therapies in medicine. No cure? Find the stories and follow those paths.”

“Narrative medicine allows the telling of a story, the discovery of truth, its sharing and consequences. Help write a happy ending.”

Leading integrative veterinarian Richard Palmquist will describe how he went from skeptic to champion of integrative veterinary medicine through witnessing miraculous outcomes from integrative approaches, after conventional options were exhausted.

“I suggested we apply a dose of Caulophyllum 30c…about 45 minutes later a live calf was eased into the world.

I readily accept this is not a scientific experiment that would satisfy the cynically minded, but when one saw this repeatedly over a period of 15 years it held much greater sway for us than any scientific experiment.”

“As a veterinarian now practicing homeopathy and chiropractic almost exclusively,  I have all the proof I need every day in my practice to justify these modalities.”

“It might take science >100-1000 years to categorize and understand some basic healing principles. Pioneers go first, science comes later.”

#RealSearch is actual scientific pursuit of truth without interference in design or reporting of data. It seeks causal discovery. Support it. We don’t look because we believe, we believe because we have seen so many people and animals benefit from integrative therapies. Did you know the word believe means we find truth in or feel affection for an area? It’s an interesting word when we consider its origin. When we find something true, we love. When we love we find truth. These go hand in hand with healing, too. First we look, then we test, then we believe. THEN we LIVE. BE LIVE!”

“Universities exist to provide a circle for the exploration & perfection of love. At their core each subject, each expert is examining this.”

“Pearls of wisdom handed down through the generations, scientific studies, and Chinese terminology bring together knowledge that is most certainly true. Modern science and the trend toward evidence based medicine has many pitfalls, whereas the “tried and true” passed through centuries holds as much truth for me.”

“Science is powerful and wonderful and so important. We must not lose ourselves in the game of science while ignoring healing.”

Alternative Medicine
“Holistic medicine addresses the patient as a whole – body, mind, and SPIRIT. There is a level of reality beyond, and yet enmeshed in, the physical, material universe. If I did not have an appreciation of the spiritual aspects of my patients and their caregivers, they and I would become little more than robots.

Don’t settle for treatment by a robot.”

“There is evidence-based research that holistic medicine works, but many people are quick to dismiss it because the studies are not funded by pharmaceutical companies,” she says, “the research is there if people would just do it.”

“If your veterinarian (or medical doctor for that matter) is relying strictly on published medical information for his prescribed treatment options, then his therapy will be 90% flawed. In other words, he will get it right 10% of the time.”

“Lack of ‘adequate’ research is why alternative medicine is considered alternative and is excluded from EBM. This lack of “evidence” is also an excuse for the rejection and criticism of many helpful alternative therapies by well-meaning, conventional practitioners. This attitude may lead your veterinarian astray.”

“Critics of homeopathy like to throw up the term “evidence based medicine”, as if to suggest that pharmaceutical drugs are more scientifically arrived at. If they are evidence based, why are they always being withdrawn after causing injury and death? Let’s explore the actual evidence.

Bottom line: Drug companies commit fraud in drug testing, lie about drug effectiveness and safety, publish positive articles in peer reviewed journals and then sell those drugs to the public. The FDA redacts the wrong doing from their reports.

Now you know…. pharmaceutical drugs are NOT evidence based… period.”

“How does acupuncture work? We know that it does work from thousands of years of experience.”

“Traditional Chinese Veterinary Medicine (TVCM) has been used in China for about 3000 years. Originally the practice was handed down from father to son and you were only paid if you made your patient well. So you either got good at it or your family line died out. “

“Holistic practitioners believe that vital life energy is the most important factor in the health of the patient…Because medical science has defined itself on a strictly physical basis, it is true that vitalism is unscientific. By definition, vitalism embraces a concept about a nonphysical force that can never be understood within the current scientific, medical paradigm.”



Posted in General | 9 Comments

Evidence Update- Neutering and Cancer Risk in Danish Dogs

One of the “hot topics” in veterinary medicine right now is the balance of risk and benefits to neutering. Even though I completed an extensive review of this subject in 2010, and updated it just last year, the new evidence is rolling in at brisk pace. The latest tidbit I have come across specifically touches on the specific issue of cancer risk.

M.M.E. Larsen, B. Børresen, A.T. Kristensen.  Neuter status and risk of cancer in a Danish dog population.

…From August 2005 to March 2014, 3801 canine neoplasms were reported to the Danish Veterinary Cancer Registry…The overall distribution of malignant neoplasia was 481 (38%) intact male dogs, 157 (12.5%) neutered male dogs, 404 (32%) intact female dogs and 220 (17.5%) neutered female dogs. The distribution was even between male and female dogs (50.5% and 49.5%). Compared to a known standard population of dogs, there was an overall statistically significant association of malignant neoplasia with neuter status in both sexes. For both genders this was significant for lymphoma, mast cell tumors and osteosarcomas. For neutered females, but not males, there was increased risk of hemangiosarcoma, squamous cell carcinoma and malignant melanoma. These findings indicate that there might be an association between neuter status and development of malignant neoplasia but larger prospective studies are needed to evaluate the risk of non-sex hormone dependent cancers in neutered dogs.

This was published as an abstract of a presentation at the European Society of Veterinary Oncology, so the full details of the study are not available. In particular, the breed and age of the dogs involved are factors which have proven critical to evaluating any link between neutering and cancer risk in previous studies. Hopefully, more data will become available in a full-length publication.

This study is in general agreement with some of the previous research in suggesting neutering may increase the risk of some specific cancers, and that this increase will differ between males and females. The tables below summarize previous studies on neutering and lymphoma, mast cell tumors, osteosarcoma, and hemangiosarcoma, so these data can be put in context.

As always, it is critical to evaluate the importance of any change in cancer risk with other health effects, including potential benefits. There is, for example, evidence that mammary cancer rates are decreased by neutering. And there is also some evidence that neutered animals live longer than intact animals, and if this is true it would certainly influence any decision about what action to take based on the new data about neutering and cancer risk. The subject is complex, and simple rules of thumb are unlikely to be very useful in making decisions about what to do for individual pets. Fortunately, as more and more data become available, we should be able to do a better job of making informed decisions about neutering in particular patients.



Table 1: Cited reports examining the relationship between neuter status and risk of osteosarcoma in dogs

Study More Common Neutered More Common Intact No Difference Comments
Ru, G. 1998 OverallOR=2.2 Purebred dogs only, case-control study
Cooley, D. 2002 Males neutered <1yrRR=3.8

(95% CI=1.5-9.2)


Females neutered <1yr


(95% CI=1.1-8.3)

Males neutered 1-3.5yrsRR=1.7

(95% CI=0.7–4.3)


Males neutered >3.5yrs


(95% CI=0.6–3.5)


Females neutered 1-5yrs


(95% CI=0.5–3.8)


Females neutered >5yrs


(95% CI=0.4–3.2)

Rottweilers only, retrospective cohort
Hoffman, J.M. 2013 Overall Multiple breeds/mixed-breeds, retrospective cohort


This study found an increased risk with neutering for both males and females, but no information on age at neutering or breed was provided.
Table 2: Cited reports examining the relationship between neuter status and risk of hemangiosarcoma in dogs

Study More Common Neutered More Common Intact No Difference Comments
Prymak, C. 1988 FemalesOR=2.2

(95% CI=1.2-4.1)


Males Splenic HSA only, retrospective cohort
Ware, W. 1999 FemalesRR=5.33

(95% CI=3.96-7.19)




(95% CI=1.21-1.98)

Differences not found for all breeds, retrospective cohort, cardiac HSA only
Torres de la Riva, G. 2013 Females neutered >12mosRR=6.1

(95% CI=1.18-31.37)

MalesFemales neutered <12mos Golden retrievers only, retrospective cohort
Hart, B.L. 2014 All groups Golden retrievers & Labrador retrievers, retrospective cohort
Zink, M.C. 2014 Males neutered >12mosOR=5.3

(95% CI=1.5-18.2)


Females overall


(95% CI=2.8-29.4)


Females neutered >12mos


(95% CI=3.5-38.5)


Females neutered <6mos


(95% CI=1.7-21.3)

Males overallOR=0.6

(95% CI=0.3-1.4)


Males neutered <6mos


(95% CI=0.6-7.3)

Viszlas only, online owner survey


This study found an increased risk with neutering for females and not for males, but no information on age at neutering or breed was provided.



Table 3: Cited reports examining the relationship between neuter status and risk of lymphosarcoma in dogs

Study More Common Neutered More Common Intact No Difference Comments
Villamil, JA. 2009 Intact Female OR=0.69(95% CI=0.63-0.74) Intact MaleOR=1.32

(95% CI=1.24-1.41)


Neutered Male


(95% CI=0.85-0.97)

Neutered FemaleOR=1.02 (95% CI=0.96-1.08) Multiple breeds, matched case-control study, OR is for development of lymphoma in each sex category
Torres de la Riva, G. 2013 Males neutered <12mos FemalesMales neutered >12mos Golden retrievers only, retrospective cohort
Hoffman, J.M. 2013 Overall Multiple breeds/mixed-breeds, retrospective cohort
Hart, B.L. 2014 Male & Female Goldens neutered 6-11mos  Males and Female Goldens neutered <6mos and >1year 

All Labradors

Golden retrievers & Labrador retrievers, retrospective cohort
Zink, M.C. 2014 OverallOR= 4.3

(95% CI=1.9-9.7)


Neutered <6mos


(95% CI=1.3-9.6)


Neutered 7-12mos


(95% CI=1.0-9.4)


Neutered >12mos


(95% CI=2.2-12.0)

Viszlas only, online owner survey, OR reference category is intact animals


This study found an increased risk with neutering for both males and females, but no information on age at neutering or breed was provided.


Table 4: Cited reports examining the relationship between neuter status and risk of mast cell neoplasia in dogs

Study More Common Neutered More Common Intact No Difference Comments
White, CR. 2011 FemalesOR=4.11

(95% CI=2.19–7.69)


(95% CI=0.90–2.09)

Case/control study, multiple breeds
Hoffman, J.M. 2013 Overall Multiple breeds/mixed-breeds, retrospective cohort
Torres de la Riva, G. 2013 Females2.3% of neutered <12mos

5.7% of neutered >12mos

No cases in intact

Males1.7% of neutered <12mos

4.2% of neutered >12mos

2.8% of intact

Golden retrievers only, retrospective cohort
Hart, B.L. 2014 Female Goldensneutered <6mos & >1yr All Golden MalesAll Labradors Golden retrievers & Labrador retrievers, retrospective cohort
Zink, M.C. 2014 OverallOR=3.5

(95% CI=2.3-5.4)
Neutered <6mos


(95% CI=1.6-5.0)


Neutered 7-12mos


(95% CI=1.1-3.9)


Neutered >12mos


(95% CI=2.9-7.0)

Viszlas only, online owner survey, OR reference category is intact animals


This study found an increased risk with neutering for both males and females, but no information on age at neutering or breed was provided.




Posted in Science-Based Veterinary Medicine | 9 Comments

Longevity & Causes of Death in Pet Cats

Basic epidemiological research, identifying the most common diseases and causes of death and risk factors for these, is the foundation of preventative medicine. Unfortunately, such research is often scarce in veterinary medicine. Collecting data on a large population of animals over an extended period of time is expensive and time-consuming, and since there is generally no direct economic incentive for doing so and little private or government funding for such research, studies like this are seldom done.

Some longitudinal data have been collected by insurance companies, large corporate practices, and some non-profit organizations supporting veterinary research. A recent paper has reported some information from another source, VetCompass. This is an effort of the Royal Veterinary College to collect clinical data from private veterinary practices and use this data to improve our understanding of health and disease in veterinary patients. This is a potentially rich source of information, and such efforts could contribute significantly to the evidence base needed to improve healthcare for our pets.

O’Neill DG, Church DB, McGreevy PD, Thomson PC, Brodbelt DC. Longevity and mortality of cats attending primary care veterinary practices in England. J Feline Med Surg. 2015 Feb;17(2):125-33. doi: 10.1177/1098612X14536176. Epub 2014 Jun 12.

A brief version of the results can be found on the VetCompass site. The study used data from over 100,000 cats at 90 different practices in England, which allowed for some pretty robust statistical analysis. A random sample of cats who had died was used to investigate longevity and causes of death

A couple of interesting patterns emerged from these. The median longevity was 14 years, but this did vary quite a bit by breed, and there were two peaks in mortality—one at 1 year of age and another at 16 years of age (Figure 1). This suggests that cats pass through a period of relative high risk at about 1 year, but those who get through this time have a could chance of living well into their teens.

longevity chart

The leading cause of death is listed as trauma, which I initially found surprising (Table 2). However, when causes of death are broken down by age group, this is the #1 cause for cats under 5 years of age. It is still #6 for cats over 5, which suggests a higher proportion of outdoor cats than I typically see in my area. For the young cats, trauma accounted for 47% of the death (half of these from road accidents), far more than the second-leading cause of death, viral infectious disease, which accounted for only 6.6%.This is a reminder of why an outdoor lifestyle is a very risky one for domestic cats.

For cats over 5 years of age, kidney disease was the leading cause of death, accounting for 13.6% of the deaths evaluated. Unfortunately, the second-leading cause was the rather uninformative category of “non-specific illness.”

mortality cats

The study also used a linear regression analysis to evaluate factors associated with longevity. In addition to finding that mixed-breed lived longer than purebred cats, the data did show a longevity benefit to neutering. Neutered female cats lived roughly six months longer than intact female cats. Intact male cats, however, died nearly two years younger than neutered male cats. The reasons for this difference are likely multiple. While neutering has been associated with greater longevity in a variety of species, and there seems to be some underlying physiological factor that contributes to greater longevity in neutered individuals. However, there are also likely other differences that have more to do with husbandry than biology. If, for example, neutered male cats are less likely to be allowed outside than intact male cats, which is almost certainly the case, then the risk of being an outdoor cat will confound any apparent effect of neuter status on longevity.

There are, as always, limitations to this study. The accuracy of causes of death could not be independently verified, and many were lumped under the vague heading of “non-specific illness.” The evidence that comes out of retrospective studies of medical records is only as good as the information that goes into the records, so there is always a significant risk of error when dealing with a large and diverse group of clinicians who haven’t all been trained in the same way to use the same record-keeping practices.

The results of this study also apply only to the population studies, which means cats of this particular mix of breeds, lifestyles, and those with similar husbandry and environmental circumstances. The results likely would be different in some significant respects from, for example, an urban U.S. cat population. Nevertheless, the accumulation of such information from different sources over time provides valuable knowledge about the factors that influence health, disease, and longevity in our pet cats, and more such research is critical to improving the care we provide and the health of our pets.


Posted in Science-Based Veterinary Medicine | 15 Comments

What You Know that Ain’t Necessarily So: Antibiotics, Endocarditis, & Dentistry

I recently gave a lecture at the Western Veterinary Conference called “What You Know that Ain’t Necessarily So.” The purpose of this was to take some common or controversial beliefs and practices in veterinary medicine and discuss the scientific evidence pertaining to these. This was not intended as a definitive, “final word” on these subjects, but as an illustration of how weak and problematic the evidence often is even behind widely held beliefs. In some cases, these practices or ideas may actually be valid, but without good quality scientific evidence, we should always be cautious and skeptical about them.

Eventually, I will post recordings of the presentations themselves, but for now I am posting a summary of each topic.

Each starts with a focused clinical question using the PICO format.

P– Patient, Problem Define clearly the patient in terms of signalment, health status, and other factors relevant to the treatment, diagnostic test, or other intervention you are considering. Also clearly and narrowly define the problem and any relevant comorbidities. This is a routine part of good clinical practice and so does not represent “extra work” when employed as part of the EBVM process.

I– Intervention Be specific about what you are considering doing, what test, drug, procedure, or other intervention you need information about.

C– Comparator What might you do instead of the intervention you are considering? Nothing is done in isolation, and the value of most of our interventions can only be measured relative to the alternatives. Always remember that educating the client, rather than selling a product or procedure, should often be considered as an alternative to any intervention you are contemplating.

O– Outcome What is the goal of doing something? What, in particular, does the client wish to accomplish. Being clear and explicit, with yourself and the client, about what you are trying to achieve (cure, extended life, improved performance, decreased discomfort, etc.) is essentially in evidence-based practice.

This is then followed by a summary of the evidence available at each of the levels in the following pyramid (which is a pragmatic reinterpretation of the classical pyramid of evidence that is a bit more useful for general practice veterinarians).

evidence pyramid

Finally, I list the Bottom Line, which is my interpretation of the evidence.

Antibiotics, Endocarditis, & Dentistry

  1. Clinical question

P- dogs & cats with periodontal disease

I- prophylactic antibiotics with dentistry

C- no antibiotics with dentistry

O- incidence of bacterial endocarditis

2. Synthetic Veterinary Literature

a. No systematic reviews:
b. No critically appraised topics

c. Guidelines-

…use of a systemically administered antibiotic is recommended to reduce bacteremia for animals that are immune compromised, have underlying systemic disease (such as clinically-evident cardiac, hepatic, and renal diseases) and/or when severe oral infection is present.

American Veterinary Dental College

3. Primary Veterinary Literature

Retrospective review of records for ~59,000 dogs with periodontal disease

periodontal disease was associated with cardiovascular-related conditions, such as endocarditis and cardiomyopathy.

  • Concerns about diagnostic criteria
  • Many data inconsistent with previous findings
  • Study design not appropriate to establish causal relationship

Glickman, L.T. (2009)

  • Retrospective case (70)/control(80) study
  • No association between dental disease or Tx and endocarditis

Peddle, G.D. (2009)

4. Human Literature

a. Systematic Reviews

There remains no evidence about whether antibiotic prophylaxis is effective or ineffective against bacterial endocarditis in people at risk who are about to undergo an invasive dental procedure. It is not clear whether the potential harms and costs of antibiotic administration outweigh any beneficial effect.

Glenny, A.M. (2013)

b. Clinical Practice Guidelines

Today, antibiotics before dental procedures are only recommended for patients…who have:

  • A prosthetic heart valve or who have had a heart valve repaired with prosthetic material.
  • A history of endocarditis.
  • A heart transplant with abnormal heart valve function
  • Certain congenital heart defects

American Heart Association

Antibiotic prophylaxis against infective endocarditis is not recommended:

  • for people undergoing dental procedures
  • for people undergoing non-dental procedures at the following sites:
  • upper and lower gastrointestinal tract
  • genitourinary tract
  • upper and lower respiratory tract

Chlorhexidine mouthwash should not be offered as prophylaxis against infective endocarditis to people at risk of infective endocarditis undergoing dental procedures.

National Institute for Health & Care Excellence

Bottom Line

  • Endocarditis is rare
  • Dental treatment is probably not a major risk factor for endocarditis
  • Antibiotics with dentistry are probably not useful in preventing endocarditis

Fun Fact!

  • Antibiotics with dentistry are probably not useful in preventing endocarditis
  • Overall bacteremia in 6 blood samples-
  • Extraction + amoxicillin- 56%
  • Extraction + placebo- 80%
  • Toothbrushing- 32%

Although amoxicillin has a significant impact on bacteremia resulting from a single-tooth extraction, given the greater frequency for oral hygiene, toothbrushing may be a greater threat for individuals at risk for infective endocarditis.

Lockhart, P.B. (2008)

Glenny AM, et al. Antibiotics for the prophylaxis of bacterial endocarditis in dentistry. Cochrane Database Syst Rev. 2013 Oct 9;10:CD003813.

Lockhart, PB. et al. Bacteremia Associated With Toothbrushing and Dental Extraction. Circulation. 2008; 117: 3118-3125.

Peddle GD, et al. Association of periodontal disease, oral procedures, and other clinical findings with bacterial endocarditis in dogs. J Am Vet Med Assoc. 2009 Jan 1;234(1):100-7.

Glickman LT, et al. Evaluation of the risk of endocarditis and other cardiovascular events on the basis of the severity of periodontal disease in dogs. J Am Vet Med Assoc. 2009 Feb 15;234(4):486-94.



Posted in General | 1 Comment

Jimmy Kimmel Gets Hate Mail (I feel your pain, Jimmy)

I review my own hate mail here from time to time (I’m actually overdue for another summary, so stay tuned). I totally get what Jimmy’s dealing with here!



Posted in Humor | Leave a comment