An abstract presented at this year’s American College of Veterinary Internal Medicine reports on a study hypothesizing that low level laser therapy would shorten recovery times in dogs having back surgery for ruptured intervertebral disks and hind limb paralysis.

C.C. Williams; G. Barone. Is Low Level Laser Therapy an Effective Adjunctive Treatment to Hemilaminectomy in Dogs with Acute Onset Parapleglia Secondary to Intervertebral Disc Disease? Proceedings, American College of Veterinary Internal Medicine Forum, Denver, CO. June, 2010.

I’ve reviewed the evidence for cold laser therapy before, and it is generally of low quality and mixed. Overall, it is possible this therapy could have beneficial effects, but it is far from convincingly demonstrated at this point.

I would have expected this small study to find positive results. Of course most studies do regardless of the truth of the underlying hypothesis, which is why preclinical evidence and replication are so critical to effective evaluation of medical interventions. And unfortunately, many investigators and journal editors are reluctant to publish negative results, even though these are the most useful results. So I give these authors great credit for having the intellectual integrity to publish results that do not support their original hypothesis. That is how good science should be done. (Of course, they conclude by suggesting that the negative results were merely an artifact of the small size of the study not truly evidence that their hypothesis was incorrect. Such attempts to put the most positive possible spin on negative results are ubiquitous and probable unavoidable, so that shouldn’t be held against them).

The study involved 17 dogs with naturally occurring disease, ruptured intervertebral disks leading to partial or complete hind limb paralysis. All dogs had surgery (hemilaminectomy). They were divided into a group that also received 4 days of laser therapy following surgery and a group that did not. It is not clear if this allocation was random, or if there were any significant differences in the composition of the two groups. These are very important factors in evaluating the meaning of the results.

There is also no mention of any blinding, placebo control, or other attempt to control for possible bias beyond utilizing the same pain medication protocol for both groups. This significantly raises the risk of bias in the study. Such bias would almost certainly favor a positive result.

In any case, the investigators found no difference in recovery time between the two groups. Given the limited bias controls in the study, this is a bit surprising. Certainly, this small study cannot be taken as definitive regardless of the results. But it is one more bit of evidence to consider in the overall evaluation of the possible uses of cold laser therapy, and a bit which shifts the balance slightly in the negative direction.

Update: After this post was published, I became aware of a second, very similar study with different results:

W.E. Draper; T.A. Schubert. Low Level Laser Therapy as an Adjunctive Therapy to Thoracolumbar Decompression for Canine Intervertebral Disk Disease.

This study followed 36 dogs with acute hind limb weakness or paralysis due to intervertebral disk rupture. These dogs were assigned by alternating allocation to receive standard surgical therapy and post-operative laser therapy or standard treatment only. There was, again, no blinding or placebo control. The outcome measure assessed was the average time until the dogs in each group could walk. Those dogs receiving laser therapy were ambulatory after an average of about 6 days, compared to about 12 days for those not in the laser treatment group.

These positive results conflict with those of the other study. Again, positive results are what I would expect from an unblinded and uncontrolled trial, so they must be interpreted cautiously. Though the outcome measure itself is appropriate, it can involve some subjective judgments, and without randomization, blinding, and placebo controls, it is impossible to be certain that the treatment and control groups did not differ in some relevant way other than the treatment under investigation.

So from the point of view of an evidence-based analysis of the preponderance of the data, these two studies do little to settle the question of what if any value cold laser therapy might have in intervertebral disk disease. Their different results may be due to differences in patient population, laser treatment technique, or some other factor that obscures the true benefit of laser therapy in the first study. Or, they may differ because the second study was subject to some uncontrolled bias that did not operate in the first. I any case, the question is still an open one, and hopefully as more evidence accumulates we will be able to answer it more clearly.

I initially wrote about Evolution Diet, and its promoter Eric Weisman, in 2009. In my first article, I primarily addressed the  irresponsible and false advertising for the product, and I only touched briefly on Mr. Weisman’s bogus academic credentials and anti-scientific philosophy. Then a few months ago, thanks to information from a reader, I wrote an update which specifically addressed Mr. Weisman’s long history of violating the laws governing his work as a chiropractor as well as those regulating the practice of veterinary medicine. Beyond simply having a unscientific and utterly false set of beliefs about pet health and nutrition, and an egregiously misleading and inappropriate approach to marketing his products, Mr. Weisman was also clearly a scam artist with no regard for the reasonable and appropriate laws governing veterinary and human medicine.

Fortunately, it now appears that finally, almost 30 years after the first action taken against Mr. Weisman in 1982 by the Minnesota Board of Chiropractic, Mr. Weisman will face criminal charges for his actions. According to news reports, he will face 58 counts, including practicing human and veterinary medicine without a license and animal cruelty. I have argued before that the legal system does not effectively control even dramatic cases of quackery and medical fraud, and it is disappointing the Mr. Weisman has been able to continue to profit from taking advantage of sick people and the owners of sick animals for so many decades. But it is encouraging to see him face at least some consequences at last.

The news reports contain some quite horrific examples of Mr. Weisman’s conduct. He allegedly prescribed nutritional and supplement “treatments’ for people with cancer, diagnosed and treated animals with cancer (including some who did not actually have cancer), and consistently falsely represented himself as trained and qualified to diagnose and treat both human and animal illness.

Perhaps the most disturbing story for me as a veterinarian was of a cat Mr. Weisman brought to the veterinary hospital at the University of Minnesota.

Weisman brought in a cat he suspected had kidney failure and cancerous lesions, the complaint said. According to the U’s veterinarian, the cat had neither – it died of pneumonia, was unable to absorb nutrients from the food it ate and had broken bones in each of its front legs. The suspected cancerous lesions, the veterinarian said, were actually scabs caused by the cat walking on its joints instead of its broken feet, the complaint said.

That someone capable of such cruelty could present himself as a public benefactor and a martyr seems inconceivable, but Mr. Weisman’s delusions include just such a perception of himself.

[I am] being attacked because I try to help make a better, more just society. I try to help those that do not have help or are not getting good assistance.

This case illustrates quite starkly the real harm and suffering that can result from irrational and unscientific beliefs about health and disease, and from the actions of individuals who are so blindly committed to such beliefs that they are capable of inflicting terrible harm on those who come to them for help while still seeing themselves as heroes and victims of government and the conventional medical profession.

As promised, here is the first tidbit out of Massimo Pigliucci’s Nonsense on Stilts that I want to share. (Technically, it’s not Dr. Pigliucci’s tidbit since he is summarizing part of another book, John Casti’s Paradigms Lost. But Piglucci’s book is where I found it.) These red flags make a nice addition to the various signs of medical nonsense I’ve discussed before (1, 2, 3). Since I have not read the original source for these qualities of pseudoscience, and they were listed but not discussed in detail by Dr. Pigliucci, I may not be interpreting them in precisely the same way as Dr. Casti intended, but they do resonate with my own experiences dealing with proponents of pseudoscience.

1. Anachronistic Thinking: I take this to mean both an inappropriate reverence for the supposed historical longevity of an idea as well as ways of looking at health and disease that come from historical eras before a scientific understanding was possible and that are essentially mythological. Claiming that Traditional Chinese Medicine or acupuncture or some other therapy are thousands of years old (which often isn’t true anyway), and implying that this says something positive about the effectiveness of the approach is an example of anachronistic thinking. So is employing mystical, pre-scientific models of health and disease, such as referring to unmeasurable “energies” as the source of health or illness and the like.

2. Glorification of Mysteries: A mystical perspective often requires that the core truth about something be ultimately unknowable. While science accepts that there is much we do not know, and that there may be things we cannot know, it is fundamentally based on the premise that we can and should try to understand the natural world. If someone tells you health and disease are dependent on mysterious spiritual essences that can never be rationally understood or empirically examined, then you are dealing with pseudoscience.

3. Appeal to Myths: Myths are central to the justification of many pseudoscientific ideas. Fables and other narratives that are unproven or manifestly untrue lie behind non-medical pseudoscience, such as the study of UFOs and cryptozoology, as well as many pseudoscientific theories in medicine. The stories told about toxins in our environment, the mythology about how the natural history of dogs and cats requires them to eat raw diets, the stories about how vaccines and conventional medicines damage the immune system or otherwise do more harm than good, are all examples of myths that are used to justify pseudoscientific approaches to medicine.

4. A Cavalier Approach to Evidence: It is becoming more popular for advocates of pseudoscientific theories, such as homeopathy and homotoxicology for example, to pretend that they are approaching their ideas in an evidence-based manner. However, a closer inspection of their arguments finds an excessive and inappropriate reliance on testimonials, traditions, and other low-quality narrative forms of evidence along with a disdain for clinical trials and pre-clinical evidence. This is not surprising since testimonial narratives are far more likely to appear to validate such approaches than are higher quality forms of evidence.

This goes along with two other characteristics cited by Dr. Pigliucci which seem closely related, “explanation by scenario” and “‘literary’ rather than empirically based interpretations of facts. Pseudoscience is very much an enterprise which tells compelling stories and dresses them up to look like science but which fails to adhere to the methodological core of science, which is objective and systematic collection and analysis of empirical data intended to validate or invalidate the specific predictions of coherent theories about the natural world.

5. Extreme Resistance to Revising One’s Position: Cognitive dissonance is a powerful force in all of us. But pseudoscience as a collaborative social activity is often deliberately focused on maintaining and buttressing beliefs, whereas science is specifically intended to continuously updated and, when necessary, replace its own theories. Science may often be wrong, but as Pigliucci points out, it is always scientists who discover and reveal the errors of other scientists, not those who criticize the scientific enterprise from outside. This emphasis on disproving gives science, unfortunately, an aura of negativity which hampers its public relations. But this is to some extent a function of the very nature of the activity, which is to disprove rather than validate ideas. Negative results are more reliable because our cognitive biases are designed to support and maintain our beliefs. So if a particular medical approach is designed to be self-sustaining and criticism of it is viewed with great hostility (which can so easily and often be seen in the comments posted on this blog), then that approach is likely to be pseudoscience.

6. A Tendency to Shift the Burden of Proof: It is axiomatic in scientific discourse that those who make extraordinary claims bear the burden of providing evidence for these claims. Since pseudoscientific approaches to medicine often lack the support of compelling empirical evidence, advocates for them frequently attempt to shift this burden to critics. It makes no sense, however, to demand that critics prove an implausible idea untrue. If I claim to be the President of the United States, should that claim be automatically accepted unless a skeptic collects sufficient evidence to disprove it, or should I be expected to be the one to prove such an unlikely assertion before it is accepted?

7. Sympathy for a Theory Just Because It’s New or Daring: Pseudoscience is often centered on supposedly new ideas (though these often turn out to be recycled) which lone geniuses claim to have discovered and which mainstream science has somehow overlooked. Often these ideas are dramatic departures from conventional understanding which, if true, would replace the dominant paradigm. It is natural to see such unexpected and dramatic claims as appealing. In America in particular, I think, we have a sympathy for the rebel and the outsider. However, the less exciting reality is that most new ideas, conventional or unconventional, turn out to be wrong. And dramatic revolutions in scientific thinking are uncommon. We simply forget all the new and daring ideas that turned out to be wrong, and remember those few that were eventually validated. This gives us an inaccurate sense of how likely such paradigm shifts are. A hallmark of pseudoscience, then, is what I have elsewhere called the Galileo Complex, in which ideas are viewed positively because they seem new and dramatic.

There are different ways to employ alternative medical therapies. Sometimes they are used in place of conventional, scientific medicine. More commonly, they are used along with conventional therapy and simply given the credit for any improvement. However, in either case there is frequently little or no research data to show whether or not such therapies are beneficial or harmful. A couple of recent studies addressing this issue have appeared which found no benefit to so-called integrative use of CAM therapies and significant harm to the replacement of conventional cancer treatment with these alternative approaches.

Han E, Johnson N, Delamelena T, Glissmeyer M, Steinbock K. Alternative therapy used as primary treatment for breast cancer negatively impacts outcomes. Ann Surg Oncol 2011;Jan 12 [Epub ahead of print].

The first study looked at 61 patients with treatable breast cancer who either declined or delayed conventional therapy in favor of alternative approaches. The mortality was significantly increased and the success of treatment greatly decreased in these patients. Those who declined conventional therapy altogether did especially poorly.

Judson P, Dickson E, Xiong Y, Peterson J, Geller M, Ghebre R et al. A prospective, randomized trial of complementary/alternative medicine for women with ovarian cancer [Abstracts Presented for the 41st Annual Meeting of the Society of Gynecologic Oncologists, Annual Meeting of the Society of Gynecologic Oncologists]. Gynecol Oncol 2010; 116(S2):S142-S143.

The second study looked at 43 women with ovarian cancer who were treated with chemotherapy alone or chemotherapy with hypnosis, healing touch, and massage. No differences in objective measures nor in quality of life were found between the standard care and the “integrative” care groups.

Obviously, these studies only involved a limited number of patients with particular conditions and particular CAM approaches, so they cannot be viewed as anything like a definitive statement on the value, if any, of alternative therapies alone or in combination with conventional cancer treatment. However, these alternatives are often marketed with confident pronouncements about their value that go well beyond any claims that could be justified by the available evidence. If CAM proponents wish to see their therapies used as replacements for conventional treatment or even as adjuncts to it, the onus is on them to demonstrate the safety and the benefits of such approaches.

These studies clearly do not support the use of these therapies, particularly when substituted for established treatments. Instead they show that there is a great danger in replacing treatments with known risks and benefits with treatments that have not demonstrated their worth, and that we cannot simply assume that even benign therapies like massage will necessarily benefit patients with cancer.