The SkeptVet on Science-Based Medicine: BARF Diets

I just wanted to let everyone know that I have a guest post out today on the Science-Based Medicine blog, Raw Meat and Bones Diet for Dogs: It’s Enough to make you BARF. I have followed SBM for a long time, and I consider it the premier site for reliable, scientific analysis of alternative medical approaches, so I’m very pleased to have this opportunity to bring science-based veterinary medical information to a wider audience, and to illustrate the relationship between unscientific approaches in both human and veterinary medicine. Hopefully, if the response is positive I’ll be contributing additional articles in the future.

Posted in Nutrition | 11 Comments

From ACVIM Forum 2010– Poster: Injectable nutraceutical for cats

Systemic Effects of a Commercial Preparation of Chondrotin Sulfate, Hyaluronic Acid and N-Acetyl-D-Glucosamine When Administered Parenterally to Healthy Cats

M.R. Lappin; J.K. Veir; C.B. Webb

This poster investigated an injectable nutraceutical containing glucosamine, chondroitin, and hyaluronic acid. I’ve written about glucosamine/chondroitin before, and despite the fact that oral products are almost universally recommended and used in both human and veterinary medicine, there is very little reason to think they are helpful. There is slightly better hope for injectable products, thought the evidence is still pretty lackluster given how long and widely used these products are. Still, with the lack of safe and effective therapies for arthritis in cats, I understand the desire to keep trying these things in the hopes that one of them will eventually be clearly shown to be of some benefit. The cynic in me also recognizes that they are a lucrative area in the pet care market, and that any evidence supporting a new product could translate into better sales.

In this study, the investigators injected the product into 8 healthy cats 5 times over 4 months and measured a number of indices of inflammation, oxidative stress, and anti-oxidation ability (a total of 14 measures alltogether) as well as routine bloodwork and urinalysis at 4 different measurement points.

No change was observed in routine bloodwork or urinalysis. The measure of oxidative stress decreased at 1/4 measurement points. The measure of blood anti-oxidant ability did not change significantly. Of the 12 measures of inflammatory cells and signaling molecules, 4 showed changes. Two types of inflammatory cell counts decreased, one at 1/4 time points, the other at 4/4 time points. Two inflammatory signaling molecules increased,  both at 2/4 time points.

Overall, the study suggests some systemic response to the injection, though only a few of the variables measured exhibited any change. The nature of the change was inconsistent, since some markers of inflammation decreased and others increased. Likewise, the anti-oxidant effects were not robust, with one marker unchanged and the other changed only at 1/4 time points. There was, of course, no control group given that this was a small pilot project, but this makes it impossible to know whether the changes that did occur were strictly due to the product or just the injection process. Also, these clinical laboratory tests are only markers of activity within the body’s inflammatory and anti-oxidant systems, and they do not necessarily indicate any positive or negative clinical effect.

While it is important to conduct such small scale trials to look for safety concerns and to justify further, more clinically relevant research, the data generated here does not strongly suggest the product is likely to have a big impact on inflammatory disease. The authors conclude that, “Some of the findings (decreased oxidative stress, increased anti-oxidant capability, and increased IL10 concentrations) could be of potential benefit to cats with inflammatory diseases and suggest that controlled studies of clinically affected cats are indicated.” This is appropriately qualified (“could be of potential benefit”), but such equivocal findings hardly seem a reason for great optimism, especially given the existing literature on glucosamine/chondroitin products, which is extensive and generally not impressive in terms of supporting a clinical benefit. There’s nothing wrong with further research, of course, and it is true that we lack good therapies for inflammatory urinary tract and joint diseases in cats, but I can’t help but feel this isn’t the most fruitful use of limited research resources, especially given the number of times I’ve had to hear lecturers today say, “At this time, there is no clinical research to support….” with regard to equally or even more pressing problems.

Posted in Herbs and Supplements | Leave a comment

From ACVIM Forum 2010–Poster: Antibodies to Feline Vaccines

I’m currently attending the American College of Veterinary Internal Medicine (ACVIM) continuing education forum, followed by the Evidence-Based Veterinary Medicine Association (EBVMA) symposium, and between lectures, labs, and other events I’m going to try and post tidbits of interest I come across.

This morning I looked at the poster presentations. Posters at scientific meetings are like mini journal articles. They usually report on small studies, often with significant methodological limitations, and they are considered a lower level of evidence than peer-reviewed papers in the journals. This is not a criticism of them as they are a very important starting point for deciding whether to pursue new ideas. It is just important to recognize their limitations and to take a cautious approach to both positive and negative findings presented as posters.

Some researchers are looking at a possibility that leftover bits of feline kidney proteins in vaccines manufactured using cat kidney cells might be a risk factor for immune-mediated diseases which are relatively common in the cat, especially some types of kidney disease and inflammatory liver and intestinal diseases. A couple of papers (1, 2, 3) have shown that cats do form antibodies to some of these proteins after receiving vaccines, but no conclusive evidence has linked this to clinical disease. The concern is a significant one. If it is true, then changes need to be made in vaccine manufacture and use, and there is the potential to reduce significantly an important set of cat diseases. However, if it is not true, then suggestive but inconclusive research on the possibility will only serve to fuel anti-vaccine fears unnecessarily.

The same research group behind the previous papers presented a poster at the ACVIM forum looking for associations between bloodwork values and the presence of antibodies to several feline kidney proteins of concern.

Association Between Feline Antibody Responses to Crandell Rees Feline Kidney (CRFK) Cell Lysates, Alpha-Enolase, and Annexin A2 and Biochemical Abnormalities in 1,477 Privately-owned Cats. J.C. Whittemore; J.R. Hawley; S.V. Radecki; M.R. Lappin

 

 

In this project, blood submitted to a commercial laboratory from 1,477 cats was analyzed. No information about age, sex, vaccination or medical history, or health status was available for specific patients. 16 biochemical measures were compared with the presence of antibodies against 3 feline kidney proteins known to be present in some vaccinated cats. The results were fairly inconsistent and not supportive of the hypothesis that antibodies against feline kidney antigens in vaccines is a cause of disease. For one antigen (CRFK) there was a positive association with one of the 16 measured values, bilirubin (a measure of possible liver disease, among other things). There was also a significant negative association with 2 of the 16 values, creatinine (a measure of kidney function) and alkaline phsophatase (a measure of possible liver disease). The other two antibodies examined both had negative associations with blood sugar, a common blood protein and, for one of them, alkaline phosphatase.

In general, then, these results don’t suggest a strong association between chemistry abnormalities in the blood and the production of antibodies against feline kidney proteins found in vaccines. There was no association with most of the values measured, and most of the associations that were found were negative, which if they were clinically significant might suggest the antibodies somehow protected against liver and kidney diseases, which is highly unlikely.  Given all the limitations of the study, especially the lack of any information about the cats the blood came from, this by no means rules out the possibility that the underlying theory is correct, it simply provides a tiny bit of low-level evidence against it. Undoubtedly, this group and others will continue investigating the problem and will hopefully eventually amass sufficient information for a strong conclusion one way or the other. In the meantime, though, it is appropriate to reassure cat owners that the hypothesis is a real but so far unproven concern, and it is not yet appropriate to alter vaccination practices on the basis of it.

Posted in Vaccines | 6 Comments

Evidence-Based Canine Allergy Treatment

Allergies are an incredibly common, and frustrating, problem in pet dogs. Unlike humans, respiratory manifestations of environmental allergies are not usually very noticeable. Dogs with allergies get itchy skin, and they scratch like crazy as a result. The underlying inflammation and the scratching both lead to secondary infections, especially of the ears and skin.

There are several categories of skin allergies, including allergy reactions to fleas, to foods, and to general environmental allergens such as pollen, dust mites, and so on. There are, not surprisingly, a lot of myths about allergies, and a lot of CAM treatments recommended, as is always the case with chronic disease science does not yet have definitive cures for.  In the future I hope to address some of these, but right now I want to discuss some evidence-based recommendations for treatment of atopic dermatitis (AD: environmental allergies, as distinguished from flea or food allergies).

The veterinary dermatology community seems to have adopted not only the rhetoric but the actual practice of evidence-based medicine more effectively than the profession as a whole. There are a number of published evidence-based reviews of therapies for various skin diseases, and a new review recently appeared titled Treatment of canine atopic dermatitis: 2010 clinical practice guidelines from the International Task Force on Canine Atopic Dermatitis. (Olivry T, Deboer DJ, Favrot C, Jackson HA, Mueller RS, et al; for the International Task Force on Canine Atopic Dermatitis. Treatment of canine atopic dermatitis: 2010 clinical practice guidelines from the International Task Force on Canine Atopic Dermatitis. Vet Dermatol. 2010 Apr 23 [Epub ahead of print].) After discussing what is known about the cause and mechanisms of AD, the report reviews various treatments for acute and chronic atopy and grades the evidence and strength of the recommendations for them. I have reproduced the grading scales for evidence and recommendations and then collated the findings in the chart below.

Table 1. Categories of evidence and strengths of recommendation

Category of evidence

Ia. Evidence from meta-analysis or systematic reviews
Ib. Evidence from at least one randomized controlled trial
IIa. Evidence from at least one controlled study without randomization
IIb. Evidence from at least one other type of quasi-experimental study
III. Evidence from non-experimental descriptive studies, such as comparative studies, correlation studies, and case-control studies
IV. Evidence from expert committee reports or opinions or clinical experience of respected authorities or both
LB. Evidence from laboratory-based studies

Strength of recommendations

A. Directly based on category I evidence
B. Directly based on category II evidence or extrapolated from category I evidence
C. Directly based on category III evidence or extrapolated from category II evidence
D. Directly based on category IV evidence or extrapolated from category III evidence
E. Directly based on category LB evidence
F. Based on consensus from Specialty Task Forces
Modified from: Leung DYM et al. Ann Allergy, Asthma, Immunol 2004; 93:S1–21.

Therapy Recommendation Strength of Recommendation
Acute Flareup    
Identify & avoid allergens Treat for fleas, rule out food allergies, avoid known environmental allergens, beneficial  D
Antibiotics, Antifungals Topical or oral drugs for identified secondary bacterial or yeast infections beneficial  D
Bathing Probably washing more important than shampoo used, beneficial  B
Topical glucocorticoids Short courses very beneficial A
Oral glucocorticoids Short courses if symptoms too severe for topicals, beneficial  A
Antihistamines Not beneficial
EFA (e.g. fish oil) Not beneficial
Tacrolimus Not beneficial
Cyclosporin Not beneficial
     
Chronic Treatment    
Diet trial for food allergy Beneficial if food allergy part of problem  D
Flea Control Beneficial D
Allergy testing Skin or blood testing may detect allergens (not foods) that can be avoided or guide immunotherapy  C
Dust mite control Theoretically beneficial but unlikely to clinically help most dogs  C
Antibiotics, Antifungals Topical or oral drugs for identified secondary bacterial or yeast infections beneficial  D
Bathing Probably washing more important than shampoo used, weekly, beneficial  D
EFA (e.g. fish oil) Helpful in conjunction w/ other therapies, not alone, no particular dose or product, oral only; mildly beneficial  B
Topical glucocorticoids, tacrolimus Beneficial, some adverse effects especially older products  A
Oral glucocorticoids, cyclosporin Beneficial, lowest effective dose to minimize side effects  A
Injectable interferon Beneficial A
Immunotherapy (allergy shots) Beneficial  A
Phytopica (herbal) Steroid sparing effect Ib(evidence)
Antihistamines Not beneficial
Pentoxifylline Minimal benefit, risk too high Ia(evidence)
Misoprostil Minimal benefit Ia(evidence)
Tepoxalin Minimal benefit Ib(evidence)
Leukotriene inhibitors Not beneficial Ia(evidence)
Dextromethorphane Not beneficial Ia(evidence)
Capsaicin Not beneficial Ia(evidence)

Obviously, the text of the review discusses the details of these interventions and the supporting evidence (or lack thereof). The evidence is often of low quality and quantity, but the Task Force has effectively followed the principles of evidence-based medicine in basing recommendations on the best evidence that is available and acknowledging the shortcomings of this evidence where appropriate. Obviously, the strength of their recommendations, and the confidence we as practitioners place in them, should be proportional to the quality of the supporting evidence.

The therapies with the best-documented efficacy, glucocorticoids and cyclosporin, are of course those with the best understood side effects. There is no free lunch in physiology! However, it is also notable that the supposedly safer therapy almost universally recommended in general practice, antihistamines, have little to no evidence of meaningful benefit. It seems likely we give these out mostly in response to the pressure, from the owner and from ourselves, simply to do something. The evidence seems pretty clear that we need to give up this unsupported practice.

Essential fatty acid supplements (EFA, usually fish oils) do have some demonstrable efficacy, but their effects are relatively small and best used to reduce the need for other therapies, such as glucocorticoids, not as primary therapeutic agents. One herbal preparation seemed to have a steroid sparing effect based on a single well-designed clinical trial (Phytopica), but the Task Force was careful to state clearly “Whether or not similar observations would be made with other nutritional supplements has not been established, and care must be taken to not extrapolate these findings to other untested products.”

Such a review is very helpful for the ordinary vet in practice, and while the quality of the evidence is not what we would desire, having it reviewed and explicitly graded in this way is a fine example of how evidence-based medicine can and should be applied in the veterinary field even with the limitations we face.

Posted in Science-Based Veterinary Medicine | 42 Comments

Uncertainty-What It Means and What It Doesn’t

It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesn’t get confined, permanently blocked, as it has so many times before in various periods in the history of man.
Richard P. Feynman

I’ve written before about uncertainty and how it affects medical decision making and also about why pet owners often prefer simple, unambiguous answers to the messy uncertainties of reality. But I’d like to take a slightly different perspective on the issue of uncertainty in science and medicine. The fact that science is incomplete and imperfect is undeniable. Unfortunately, some people take this fact as justification for throwing out the whole enterprise of trying to understand and acquire real facts and knowledge. If vaccines don’t protect us completely, this means they are useless. If science doesn’t know everything, than anything must be possible. These naïve arguments ignore the very clear fact that uncertainty and the impossibility of knowledge are not the same thing.

There are different kind of uncertainty in science. One is the uncertainty of what we don’t know. A big part of what makes science fun is that the universe is so vastly more complex than our little brains that we are never going to be in danger of running out of new things to learn and discover. I like to imagine my own ignorance as a vast abyss yawing before me. Every day I throw in a few grains of sand, but it shows no sign of being filled in. So there is no denying that the surprising and unexpected is out there waiting for us.

But that is not the same thing as saying anything we can imagine is likely to be true. Most of our guesses about the nature of reality turn out to be wrong. Until science came along, this left us fighting over belief systems and led to a bewildering proliferation of different, interesting, and usually mutually incompatible mythologies to explain the world. Now, science is creating the kind of knowledge that works everywhere, in every culture, and that endures through time. Sure, such secure knowledge is only tidbits compared to the vastness of reality, and there is plenty that falls by the wayside. But never before have we been able to have even this much enduring knowledge. Barring the complete collapse of human civilization, we are always going to know that the heart circulates blood, that emotions live in the brain not the heart, that smallpox used to be caused by a bacterium, and so on. What we don’t know is an opportunity, not an invalidation of what we do know.

Another kind of uncertainty, though, is the uncertainty about what we know. Scientists like to say that all knowledge is provisional, tentative and subject to revision. This is true, but non-scientists tend to overread this and believe it means all knowledge is ultimately just opinion and is unreliable. Sure, theories of gravity have changed from Newton’s day to our, but if you have to leave your 8th floor apartment, you can rely confidently on the knowledge that it is better to do so by the stairway than the window. It is possible that gravity will stop working tomorrow, but I wouldn’t bet on it. So while proponents of bizarre ideas like to make much of the fact that scientific explanations are “only theories,” they ignore the fact that those ideas that endure and are refined over time can reach a point where having confidence in their truth makes a lot more sense than doubting them.

A different flavor of uncertainty about the known is statistical or probabilistic uncertainty. I recently put my age, gender, total cholesterol level, and a few other factors into a nifty little calculator that told me I have a 3% chance of dying of a heart attack in the next 10 years. So does anyone know if I’m going to die of a heart attack or not? Can anyone tell me with certainty that I will if I stop taking my fish oil and baby aspirin every day, but I’m safe if I keep taking them? No, of course not. Much scientific research generates knowledge and conclusions that are statistical, that apply reliably to groups but don’t give precise predictions for individuals. So, does this mean such knowledge is worthless for helping us decide what to do as individuals? Of course not.

If you go to a casino in Vegas and play roulette, the odds are you’re going to lose. Sure, you could win. Some people do. But most people don’t. This is a truth, though it is only a statistical or probabilistic truth. So is it worthless in helping you decide whether or not to bet the farm on red? Not at all. Casinos make lots of money betting against you, and you’re a lot more likely to be able to afford that Winnebago when you retire if you play the odds and don’t play roulette. Even though statistical truths apply imperfectly to the individual, they are real and useful guides for our choices. The uncertainty of probabilities does not justify ignoring the odds and doing whatever we like.

Uncertainty is inevitable, in science as in all areas of human life. But this doesn’t mean knowledge is an illusion and blind belief is as good as facts in deciding what to do or not to do. Human beings have changed our planet and our own lives, both for the better and for the worse, through the power of discovering and applying knowledge about the physical world. Such knowledge is limited, incomplete, tenuous, and a damn site better than guessing or hoping. And science has generated more reliable, trustworthy knowledge in the past couple centuries than hunches, guesses, and trial-and-error managed in all the rest of human history. Place your bets, ladies and gentlemen. I’m placing mine on science.

Posted in General | Leave a comment

The Placebo Effect In Song

Happy Birthday, SketpVet! 🙂

Today marks the first anniversary of this blog. Not a momentous event for the world at large, but yet another reminder of the fleeting nature of time for me. Apparently, in the last year I have put up 135 posts and the site has been visited 7468 times. I’ve certainly learned a great deal, about medicine and about writing, and I’ve met a number of interesting people. I hope it has been interesting and useful to at least a few of you.

As an anniversary post, I thought I’d put up something I started on near the beginning but never actually posted.

Last summer, I spent a week at Lark Camp, a folk music workshop/festival/party in the Mendocino Woodlands. I tend to refer to it, affectionately, as Hippie Drum Camp, mostly because I went with the idea of learning to play the bodhran (hence the “drum” part; the “hippie” part should be self-evident). Apart from a brief and agonizing (for me and everyone around me) flirtation with the clarinet in grade school, I have never played an instrument. But I’ve always gone to Celtic cultural events (and pubs) and I know all the songs, so I wanted to learn more about the music. It was a fantastic experience, and I’ve spent the last year trying to learn a couple of instruments so I can go back this summer and participate more fully.

One of the folks I met there was a fiddle player who shared a song he had written called The Placebo Effect. We had a very interesting conversation about his experiences with managing his own diabetes and trying to avoid medication, and about all of the things he had investigated or tried as part of this experience. I had just started this blog, and I thought the song offered some eloquent and funny insight into the issue of placebo effects and unproven or alternative therapies from the perspective of an intelligent, educated non-scientist. At the time, I wasn’t certain he would welcome my making the lyrics public, but I recently found he did so some time ago on his own blog so hopefully he won’t mind.

Apart from the internal merit of the wit and humor, the song illustrates how someone can come to look at the complex relationship between individual experience and scientific knowledge. It is always difficult to argue with someone who feels better after using a therapy, even if the facts are pretty clear that the therapy doesn’t work. Feeling better is real whether or not it means what the person thinks it does or has any relationship to actual physical health.

In trying to promote science-based medicine, my ultimate goal is always to steer people toward what will truly help them or their pets and to steer them away from false hope and the harm that comes from mistaken ideas about cause and effect. But I try always to remember that CAM is popular because it meets a need. It provides hope, even false hope, and it addresses the psychological dimensions of illness in ways that mainstream medicine doesn’t always (though I think this is less true in veterinary medicine for a variety of reasons). I think we can have the best of both worlds–effective science-based medicine and humane, affirming care. But to do this we have to try and understand what appeals to people about CAM and what about scientific medicine pushes them away even when it is the more likely to help them.

This song touches on the issues of uncertainty in medicine, on the fact that general data can’t always predict what will help or harm the individual, and that the slow process of scientific progress, though it is far more likely to reach the right answer in the end, is often too slow to help those who are suffering right now. None of this justifies unproven or outright bogus medicine, but it does explain a bit why even ineffective therapies can be popular, and it reminds us of some of the limitations to scientific medicine that we have to deal with in the effort to guide people towards the best, real therapies available. It also reminds us that CAM is not the sole province of the ignorant, gullible, or stupid. I don’t necessarily agree with the writer’s take on science and knowledge, but from our conversation and his blog I have no doubt he is smart and well-informed. We must be careful not to make the mistake of caricaturing or patronizing those who don’t see the issues around CAM the way we think they are best seen. This blog is as much about learning for me as it is about trying to teach others, and from this fellow and his song I think I have learned a few valuable things.

Oh, and did I mention it’s funny?

In the woods on a sunny day late in July,
all the air was abuzz with mosquito and fly.
In an effort to cope I was spraying some DEET
on my arms, elbows, shoulders,
legs, ankles, and feet,
when a fiddler came by and said
“Don’t waste your time —
there’s no evidence that that stuff
works worth a dime”.
I explained to him I wouldn’t
care if there was,
’cause it helps me so long as
I think that it does.

Chorus:
I would never reject any fake remedy;
the placebo effect is what works best on me.

If I take enough fish oil, I
need not grow old,
if I take echinacea I won’t
catch a cold.
And if I should come down with a
cold anyway,
a few doses of zinc will soon
make it okay.
Now as far as I know there’s no
clinical study
showing zinc really makes you feel
one bit less cruddy.
So it might not be true, yet
I’ve heard that it’s so.
In such matters as this there is
no way to know.

I would never reject any fake remedy;
the placebo effect is what works best on me.

If you can’t afford insulin,
I have heard tell
that ground cinnamon does the job
perfectly well.
There are herbs with strange nicknames
in English and Latin
which I’ve heard are as useful
as Pfizer’s new statin.
I suppose that some day we will
know for a fact
how a body exposed to such
cures will react.
By the time that these answers are
finally found,
I’m afraid I’ll already be
under the ground.

I would never reject any fake remedy;
the placebo effect is what works best on me.

All this week in a tent, yet my
back feels just fine
I assume all that yoga
protected my spine.
And it seems my blood pressure has
come down a bit;
I conclude making music can
help me stay fit.
These are only assumptions, they
may not be true,
and if I wanted proof, well,
my options are few.
For, to test your health habits, there’s
one thing to try:
life your life over different
and see if you die.

I would never reject any fake remedy;
the placebo effect is what works best on me.

And it really is not just good
health that’s at stake,
for the thoughts that we live by
are most of ’em fake,
and we get through each day by
accepting as right
every half-assed conception
we dreamed up last night.
If I master this dance, then it
means I’m no fool,
if I wear the right clothes it will
mean that I’m cool,
and if I could play well every
tune on this list,
it would prove to me I have a
right to exist.

I would never reject any fake remedy;
the placebo effect is what works best on me.

Though to say it out loud here takes
plenty of gall,
I think music’s the greatest
placebo of all.
For as long as we’re playing we
think life is fine
and the wide world around us is
not run by swine.
Through a skeptic might ask what
this fake joy is worth,
at least fake joy’s the kind you can
have here on earth.
So that moral that I would leave
with you is this:
do not seek tragic wisdom
where bullshit is bliss!

I would never reject any fake remedy;
the placebo effect is what works best on me.

Posted in General, Humor | 4 Comments

JAVMA Article on Electroacupuncture for IVDD

A couple of readers have asked me to comment on a study that appears in this month’s Journal of the American Veterinary Medical Association, Comparison of decompressive surgery, electroacupuncture, and decompressive surgery followed by electroacupuncture for the treatment of dogs with intervertebral disk disease with long-standing neurologic deficits.

The study was performed in Brazil at the School of Veterinary Medicine and Animal Science in Sao Paulo, where a similar study published last year and another in 2007 were also performed. The authors created 3 study groups, all of which consisted of dogs that had severe neurological disease of >48 hours duration attributed to intervertebral disk disease (IVDD). Group 1 (DSX) was a group of dogs (N=10) selected retrospectively from patients that had undergone surgery for IVDD at the authors’ hospital between 2003 and 2006. Group 2 (dogs treated with electroacupuncture-EAP, N=19) and Group 3 (dogs treated with both surgery and electroacupuncture-DSX+EAP, N=11) consisted of dogs seen at the hospital between 2006 and 2008, and patients were assigned to these groups based on their owners’ choice.

All dogs were treated with oral steroids. Dogs in Group 1 were treated surgically with a couple of different techniques and presumably with whatever unspecified medical treatment and post-surgical care the individual surgeon elected. Dogs in Group 2 were treated surgically (and again presumably with additional unspecified followup care) and were also treated with electroacupuncture. This treatment consisted of the insertion of metal electrodes into the body at points determined by “traditional Chinese theory.” Electrical current was passed through these electrodes for 20 minutes weekly for from 1-6 months. Scores were assigned to quantify the level of neurologic dysfunction initially and at 6 months after the beginning of treatment. Improvement was judged based on decrease in neurologic score and regaining the ability to walk unassisted.

The results can be summarized as follows:

  DSX EAP DSX+EAP
Score Unchanged 6/10 4/19 3/11
Score Improved 4/10 15/19 8/11

 The text indicates that the proportion of dogs in the DSX group that improved was statistically significantly lower than in the other two groups, and the proportion of DSX dogs that remained unchanged was significantly greater than in the other groups. From this, the authors concluded that “EAP was more effective than DSX for recovery of ambulation and improvement in neurologic deficits in dogs with long-standing severe deficits attributable to thoracolumbad IVDD.”

So is this conclusion justified? I believe not. To begin with, of course, we must decide what if anything this paper has to do with “acupuncture.” Electroacupuncture has been referred to as a bait-and-switch, because it is arguably not acupuncture at all. Obviously, the ancient Chinese lacked electricity, so the theories and guidelines developed for acupuncture in humans are not really relevant to the effects of electricity on the body (there were no specific guidelines for animals, and despite claims to the contrary it does not appear the Chinese routinely practiced acupuncture on animals before the mid 20th century). There is, however, a scientific medical therapy involving electrical stimulation to treat pain, transcutaneous electrical nerve stimulation (TENS). The only difference between TENS and electroacupuncture appears to be the selection of electrode location. TENS places electrodes in locations associated with known nerves, and in electroacupuncture the electrodes are placed at acupuncture points with no consistent relationship to any identifiable anatomic structures. However, by chance or perhaps some trial and error experience, some acupuncture points do happen to coincide with the locations of nerves, so it is possible that electroacupuncture might effectively be the same thing as TENS in some cases. So one might justifiably question whether any benefit seen in this study represents a validation of the theory and practice of acupuncture or an example of TENS with irrational selection of electrode locations.

However, there are other reasons to view the authors’ conclusions skeptically. A major methodological flaw of the paper is the process of selecting and assigning subjects. It is highly likely that there are biases inherent in allowing owners to choose what treatment group their pets should be in and in selecting one group retrospectively from one period of time and another prospectively during a different time period. This process does not allow the owners or researchers to be blinded in any way to the treatment, and it makes it likely that the patients and the treatment they receive in the various groups will differ with respect to many variables other than the one of interest in the study. The lack of blinding is of particular concern since the research center has consistently produced papers showing positive results for electroacupuncture and thus the researchers likely have a strong a priori bias in favor of the approach.

Very little information is presented to allow us to evaluate whether the patients differed in meaningful ways in terms of the medical therapy, surgical care, and post-surgical care they received. We do know that the EAP and DSX+EAP subjects received weekly treatments at the hospital for from 1-6 months after the onset of the study, and it is likely that they received much more intensive followup and post-surgical care (for the DSX+EAP group) as well as better owner compliance due to seeing the doctor so often after the study commenced. It is also quite possible that the differences in outcome were due to any number of differences in the populations of the various groups or the biases of the authors since these were not controlled for effectively.

There are other methodological problems, particularly the small number of subjects, but overall the two factors already discussed are enough to make me question the strong conclusions the authors draw from their results. It is certainly possible that electrical stimulation of some parts of the body could have a beneficial effect on outcome for dogs with neurological deficits attributable to IVDD. Better studies involving random prospective allocation of subjects, more consistency in the treatment of the subjects, blinding of the researchers and owners, and perhaps more precise assessment criteria would be valuable. I would be particularly interested, if there turns out to be some value to so-called electroacupuncture for this condition, in seeing a comparison of this procedure with electrode locations selected according to anatomic structures such as nerves compared with locations selected according to traditional Chinese medicine principles (insofar as such principles can be called “traditional” with respect to treating animals with electricity). It would take a robust and repeatable superiority of treatment at traditional acupuncture points compared with locations selected according to the principles of TENS to convince me that this procedure has anything to do with acupuncture.

Posted in Acupuncture | 19 Comments

Shocking Study! Chiropractors Make Unsubstantiated Medical Claims!

A new study by Edzard Ernst and Andrew Gilbey recently appeared in the New Zealand Medical Journal surveying Internet advertising claims made by individual chiropractors and major chiropractic organizations from Canada, the U.S., New Zealand, and The U.K.

They divided the claims into those for which there is reasonable evidence of some benefit (lower back pain) and those for which no good evidence of efficacy exists (headaches, migraines, colic, asthma, ear infections, neck pain, and whiplash). What is not surprising is that chiropractors, and the professional organizations that represent the profession generally, routinely suggest or outright state that their manipulations can treat conditions which they cannot. 95% of individual chiropractic websites made at least one such claim, and all of the professional associations did as well. 38% of the chiropractors made treatment claims concerning all of the conditions in the survey which chiropractic has not been shown to actually treat.

What is a bit more surprising is that many of the sites and organizations did not promote chiropractic for lower back pain, the one condition for which the evidence of some benefit is decent. Only 28% of the individual sites and 4 out of 9 association web sites specifically mentioned lower back pain. One would think they would be most aggressively advertising their treatments for the diseases for which the best evidence exists that they actually help. But remember, chiropractic is, for the most part,  really a faith-based practice founded on the non-existent subluxation and the vitalist “innate intelligence,” not an evidence-based medical specialty. It is true some individual chiropractors are exceptions to this rule and limit themselves to treating musculoskeletal pain. And there are some signs that the profession may be moving to downplay the subluxation mythology. But in general, the practice of chiropractic is still dominated by 19th century spiritualist notions and isn’t much interested in the verdict of science on its efforts.

So how do we explain the apparent de-emphasizing of the most reasonable claims chiropractic could make? I suspect that there is a deliberate effort on the part of the chiropractic profession to avoid getting limited in the public’s mind to treatment of musculoskeletal pain. Chiropractors want to be seen as an alternative choice to conventional medical providers, and they want to be involved in much more than just the treatment of musculoskeletal pain. So despite the lip service they may pay to the concept of evidence-based medicine, in reality they are convinced their treatments work for all sorts of problems regardless of the lack of evidence, and they want to protect and nurture the false impression the public may have that chiropractic is good for more than just back pain.

Posted in Chiropractic | 22 Comments

Don’t Be Such a Scientist or The Negating Culture of Science and its Costs

I recently finished reading Randy Olson’s book Don’t Be Such a Scientist, and I definitely recommend it. It is an entertaining read and has a number of useful insights into the perennial problem of communicating complex, nuanced, and incomplete scientific information in a way that is engaging and accessible and still in some meaningful sense truthful. I won’t say I agree entirely with Olson’s take on the subject, of course. Sometimes I think he lets the public off too easily, expecting too little from the intelligent lay person. And as always when making generalizations, he seems to stray sometimes into caricature and stereotype. Still, there is no denying that there is currently an enormous divide between mainstream culture and the subculture of science. The days of standing room only public science lectures, such as those of the 19th century, are gone. And the days of scientists being seen as respected and trusted white-coated heroes who invented antibiotics, stopped the scourge of polio, and won the Second World War are over too. There is now a profound suspicion of science, and intellectualism generally, in the U.S., and scientists can no longer take for granted that they will listened to, trusted, or supported by the general public unless they can compete in the busy and bewildering media from which most of us get our understanding of complex issue.

The one concept that struck me most forcefully in Olson’s book, was the image of science as fundamentally a negating enterprise. For all the reading and writing I’ve done on the subject of medical research and the dangers of simply seeking to confirm our preconceptions, I never fully appreciated the implications of this for the appearance of science to non-scientists.

It is very difficult to reliably prove an idea true. Certainly informal assessments of our personal experiences almost always confirm our pre-existing beliefs. Confirmation bias, the availability bias, cognitive dissonance, and a host of other such factors make this inevitable. But even scientific research studies, with all their attempts at controlling personal bias, will almost inevitably prove true whatever investigators set out to prove. The best way to get to the truth is to attempt to prove ideas wrong. A negative finding, especially from a source predisposed in favor of the hypothesis, is worth more than a positive finding. Of course, technically one cannot prove a negative. But the failure to disprove an idea with multiple, vigorous attempts is certainly more reliable an indicator of the idea’s veracity than multiple studies set up to confirm what is already believed to be true.

The implications of this for the culture of science, and the barriers to effective communication between scientists and non-scientists, are profound. Scientists expect criticism and see it as a sign that they and their ideas are being taken seriously. Sure, we are human and so as full of ego and narcissism as anyone else. But by training and experience, most of us acquire relatively thick skins, and we come to see strong challenges to our ideas as a good thing, a kind of intellectual personal trainer that will cause us pain but ultimately make us stronger.

I have been through the peer review process for several publications I have written, and it isn’t pretty. Seeing something I have put months of hard work into torn apart, and facing the prospect of more work to revise what I was sure was perfect to begin with, causes lots of hurt and anger. But at the end of the process, I am generally grateful that the final product is better and that I have been saved the embarrassment of public error. I understand that the criticisms are not personal (the reviews are anonymous, of course, which helps) and I accept the ego bruising as a fair price to pay for weeding out bad work and weak ideas. Likewise, I try as hard as I can to give up beliefs and practices that have been reasonably shown to be wrong, even if I am attached to them and personally convinced of their value. I trust the process, based on the logic of the underlying philosophy and the evidence of history, and this helps me to appreciate the value of the sometimes painful experience of having my ideas and work criticized.

As part of this enculturation, I also feel it normal to respectfully but aggressively criticize the ideas of others. I’ve discussed before how proponents of CAM often resent such criticism and see it as fundamentally unfair and inherently personal. In the culture of faith-based medicine, where truth is judged on the basis of one’s personal experiences or the received wisdom of one’s mentors, challenging someone’s beliefs is the same thing as challenging their intelligence, honesty, or worth. In the culture of science, no one’s beliefs are beyond challenge, at least theoretically (though of course scientists are political animals like all humans, so this principal isn’t always followed). This is one of example of the clash between the negating culture of science and other, non-scientific ways of looking at health and disease.

Olson also makes a big point of talking about how unlikeable scientists can seem to the rest of the world. This is particularly a concern for an endeavor like this blog, which is to a great extent devoted to identifying ideas which are not true and therapies which don’t work. It is far more pleasant to hear proclamations of hope and optimism than to hear all the reasons why something which purports to offer hope really doesn’t. Debunking is inherently negating, and it is easy to see why this leads to the image of skeptics as sour, curmudgeonly, and willfully choosing not to believe in anything. Of course, anyone the least bit of a skeptic themselves knows this isn’t true, just as anyone who actively practices science knows how positive and affirming it can be. The sense of wonder and discovery and the joy of figuring things out is a big part of the rewards in doing science, but for some reason they are less often communicated to the public than the contempt many scientists feel for bad ideas supported by wishful thinking, sloppy logic, and few facts. Science communicators, one might even say science entertainers, like Carl Sagan and Neil deGrasse Tyson are notable exceptions.  

So I agree with Olson that in many ways the culture of science is built on negation, on aggressive intellectual attack and defense of ideas, on a disrespect for those who make stuff up, botch their facts, and show more concern for what they wish to be true than for what really is true. This kind of negativism is not a bad thing, of course, since it is what enables the discovery or real, practical truths that benefit us all. And the negating aspects of science are not all there is to the enterprise. There is a great deal of awe and wonder, creativity, community, and true hope for meaningful progress and improvement in the world. But the negating aspects of the scientific approach do present a public relations problem. Most people seem to take a pretty quick dislike to dispassionate, cerebral, fact-based exposition and to the negation of hopeful, feel-good ideas no matter how nonsensical.

So what do we do about this? Abandoning reality for wish fulfillment doesn’t strike me as a good choice, so we are stuck having to challenge bad ideas no matter how popular. But as Olson suggests, this can at least sometimes be done with humor and humility and with frequent reminders of the elegance, wonder, and real benefit inherent in pursuing and defending the truth. While I think Olson sometimes goes too far in the degree to which he seems to suggest we simplify our messages and make them more entertaining and less instructive, nevertheless his underlying point is valid. The positions staked out by science and reason must compete in a marketplace of ideas, and some of the competitors they face are much more marketable.

The advances of science are often more complex and less obvious than the early triumphs of vaccination and antibiotics, which make them less self-evidently proof that the approach is the right one. And the misuses of scientific knowledge and technological progress are better understood, which further tarnishes the image of science. But the fundamental nature of science as a method which relies on challenge and disproof is itself a weakness from a public relations point of view. And the cultural reverence for factual accuracy and distaste for excessive, hyperbolic, and ultimately unjustified claims also sets those of us promoting science-based medicine at something of a disadvantage. Yet all of these marketing weakness are strengths from the point of view of discovering real and useful truths, so we cannot give them up.

We must strive to make what we do and what we stand for as engaging and accessible as possible without cutting the heart out of it. Being open about our own joy and passion for the truth and the scientific path to reach it is an important step, and being always clear that the truth, even when it may not be what we might wish it to be, is the only way to really better all our lives. Millennia of faith and wishful thinking have failed to accomplish what science has wrought in a few generations, and we must not allow the public to forget that. We must being humble, but at the same time not afraid to be definitive where it is justified. Homeopathy doesn’t work, vaccines don’t cause autism, and we needn’t tiptoe around those assertions to satisfy an excessive epistemological caution. And as always in life, we must make the effort to maintain our sense of humor, about ourselves as well as our ideological adversaries. This will not only make our own efforts more enjoyable to us, but it will do a lot to dispel the myth of the emotionless scientist out of touch with ordinary human feelings. We are as driven by our own feelings as anyone, we simply trust in a method of inquiry which diminishes the danger of these feelings misleading us, and hopefully we can succeed at illustrating that and thus humanizing science and scientists.

Posted in Book Reviews, General | 4 Comments

GAO Report on Deceptive Marketing and Contamination of Herbal Products

The GAO today released a report to Congress that had previously been reported on in the New York Times. The report investigated deceptive or illegal marketing practices among sellers of herbal remedies and dietary supplements. Under the Dietary Supplement Health and Education Act of 1994  (DSHEA), there is precious little restriction on manufacturers and marketers of these products. All supplements are presumed to be safe without any pre-marketing evidence required, and the FDA can only restrict such products or their sale if post-marketing surveillance, which is haphazard at best, indicates a health threat. Marketers of such products can technically only make vague claims about their products, not claiming that they prevent or treat any specific disease unless they pass the stringent standards of evidence applied to pharmaceuticals. However, this report shows that even these weak limits are being widely ignored.

Many examples of deceptive and illegal marketing practices were identified. GAO employees posing as elderly consumers were told that herbal products could cure several diseases, including cancer, that they could be substituted for prescription medications, and that they could be used safely along with medications even when there is evidence this is untrue.

The GAO also tested 40 supplements for heavy metal and pesticide contamination and found contaminates in 37 of them. The levels were low, but because such products are under-regulated, clear standards for safe levels of these substances have not been established, so it is impossible to know how much risk this poses to the consumer. Certainly, the claim that such products are “all natural” and thus safer than pharmaceuticals is belied by these test results. Can you imagine what the alternative medicine folks would say if lead or pesticides were found in prescription drugs? Yet the manufacturers of these products express no concern, and they have effectively blocked attempts by Sen. John McCain and others to strengthen the regulation of their products. So much for the David and Goliath Myth. Big Herb and his buddy Big Supplement are playing the same game as Big Pharma, they just don’t have any referee watching to see if they play by the rules.

Posted in Herbs and Supplements, Law, Regulation, and Politics | 2 Comments