3 years ago I wrote an article critical of “evolutionary medicine” as it was presented in a new book. Recently a correspondent asked me if I thought another book, Why We Get Sick: The New Science of Darwinian Medicine, by Randolph M. Nesse, MD and George C. Williams, PhD, was a more reasonable approach to the subject. It was published in 1994 and got good reviews from respected scientists like Richard Dawkins (“Buy two copies and give one to your doctor.”) and E.O. Wilson (“bringing the evolutionary vision systematically into one of the last unconquered provinces…”). I was able to obtain a copy through interlibrary loan.
The book was interesting and gave me some things to think about, but it didn’t convince me that “Darwinian medicine” is a new science, that its existence as a separate discipline is justified, or that its unique approach offers any real practical benefits for improving medical care.
Why do we get sick? A simplistic view of evolution holds that it systematically eliminates any factors that decrease fitness for survival. So why does disease persist? Why didn’t we evolve to be “fit” enough to never get sick? Because evolution is not a straightforward process.
The term “evidence-based medicine” first appeared in the medical literature in 1992. It quickly became popular and developed into a systematic enterprise. A book by Ulrich Tröhler To Improve the Evidence of Medicine: The 18th century British origins of a critical approach argues that its roots go back to the 1700s in Scotland and England. An e-mail correspondent recommended it to me. Can’t remember who, but I would like to thank him.
Francis Bacon (1561-1626) differentiated between “ordinary experience” (chance observations) and more objective “ordered experience” (methodological observations). Both of these involved empirical knowledge. It’s hard to get back into the mindset of his time, when most physicians rejected empiricism as the sphere of quacks and surgeons. Tröhler helps us understand why they did:
…since antiquity, the mark of distinction of a learned man had been the certainty of his knowledge. A doctor knew — he did not need to test his kind of knowledge empirically because this would imply acknowledgement of uncertainty.
For decades Consumer Health: A Guide to Intelligent Decisions was the only textbook available for college classes on the subject, and it is still the best: the most comprehensive and the most reliable. It was first published in 1976, and it has clearly had staying power. An updated 9th edition has just been released. The authors have changed over the years: this edition’s authors are Stephen Barrett, William London, Manfred Kroger, Harriet Hall, and Robert Baratz. It’s an invaluable compendium of information that would be useful to any consumer, and it’s unfortunate that McGraw-Hill is marketing it as an expensive textbook ($163).
What exactly is “consumer health”? The book’s preface and the table of contents are available here. They will provide the long answer to that question. The short answer is:
The book’s fundamental purpose is to provide trustworthy information and guidelines to enable people to select health products and services intelligently. (more…)
I usually rely on the Secret. Every two weeks or so the Universe offers up some bit of wacky whimsey and I have a topic for an SBM blog entry. This week the Universe has failed me. Nothing has crossed my LCD so I have no studies to evaluate and I have been unusually busy at work preventing my browsing the Interwebs for material. But try telling that to the Managing Editor. I write half to amuse myself, half to learn about the topic, and half to clarify in my own mind the topics at hand (1). So this week is content free idle thoughts for my own benefit.
I have been reading 13 Things That Don’t Make Sense by Michael Brooks. The book concerns topics in science that are unexplained by the current understanding of the laws of the universe or contradict the dominant paradigm. Well, almost. His final topic is homeopathy, and it is the one topic whose conclusions, while qualified, belong on Failblog. The first chapter concerns dark matter and dark energy and how what we can see makes up only a small fraction of the content of the universe. (more…)
Eric Topol, MD, has written a book about the convergence of the digital revolution and medicine. It is full of fascinating information and prognostication, but I wish he had given it a better title. He called it The Creative Destruction of Medicine: How the Digital Revolution Will Create Better Health Care. Medicine will not and cannot be “destroyed.” It will be improved and transformed, perhaps, but not destroyed. And any new developments will have to be evaluated for safety and effectiveness by the good old time-tested methods of science.
The future world of medicine is really exciting: science fiction is becoming real. As I read Topol’s book I serendipitously found it paraphrased by a character in another book I was reading, Chop Shop, by Tim Downs.
I see a world where no one ever dies from an adverse drug reaction; where physicians have an entire range of medicines to choose from to treat a deadly disease; where medications target tumors like smart bombs and leave surrounding tissues unharmed; where genetic susceptibility to disease can be determined in childhood, and possibly even prevented.
(If you haven’t yet discovered Downs’ hilarious “Bug Man” detective series about a crazy forensic entomologist, you have a treat in store.)
But back to non-fiction. Our world is changing almost too rapidly to comprehend: the Internet reaches everywhere, and there are far more mobile phones in the world today than toilets. We have hardly begun to tap the current potential of new technologies, and unimagined further developments await us. Topol is a qualified guide to this new world: he is a respected cardiologist and geneticist who ha s been on the forefront of wireless medicine and who was a major whistleblower in the Vioxx fiasco. He knows whereof he speaks, and he writes lucidly and accessibly.
A brief reference on the web site The Quackometer recently drew my attention to a very short book (really more of a pamphlet, in the historical sense) by Dr. Worthington Hooker, Lessons from the History of Medical Delusions, which I thought might be of interest to readers of this blog. Though published in 1850, the book contains many eloquent observations that are just as relevant to understanding how pseudoscience and quackery persist and even flourish in what we otherwise assume to be an age of scientific medicine. The book is available online as a Google eBook, and relatively cheap printed facsimiles are available as well.
Dr. Hooker was a physician, a professor at Yale, and an outspoken critic of homeopathy in it’s early days. His critique of homeopathy still resonates today, and has long drawn the ire of Hahneman loyalists, such as this one who makes reference to Dr. Hooker’s, “periodical fulminations for the destruction of Homoeopathy that have appeared like locusts or cholera at certain dates.” Though Dr. Hooker wrote an entire book discussing homeopathy, Homeopathy: An Examination of its Doctrines and Evidences, he does spare a few words here for this less-than-venerated practice:
The error I have been illustrating is carried to an extreme by the Homeopathist. He attributes palpable results to doses of medicine which are so small that they cannot produce any perceptible effect except by miracle.
Consider these statements:
…there is an evidence base for biofield therapies. (citing the Cochrane Review of Touch Therapies)
The larger issue is what constitutes “pseudoscience” and what information is worthy of dissemination to the public. Should the data from our well conducted, rigorous, randomized controlled trial [of 'biofield healing'] be dismissed because the mechanisms are unknown or because some scientists do not believe in the specific therapy?…Premature rejection of findings from rigorous randomized controlled trials are as big a threat to science as the continuation of falsehoods based on belief. Thus, as clinicians and scientists, our highest duty to patients should be to investigate promising solutions with high benefit/risk ratios, not to act as gatekeepers of information based on personal opinion.
–Jain et al, quoted here
Touch therapies may have a modest effect in pain relief. More studies on HT and Reiki in relieving pain are needed. More studies including children are also required to evaluate the effect of touch on children.
Touch Therapies are so-called as it is believed that the practitioners have touched the clients’ energy ﬁeld.
It is believed this effect occurs by exerting energy to restore, energize, and balance the energy ﬁeld disturbances using hands-on or hands-off techniques (Eden 1993). The underlying concept is that sickness and disease arise from imbalances in the vital energy ﬁeld. However, the existence of the energy ﬁeld of the human body has not been proven scientiﬁcally and thus the effect of such therapies, which are believed to exert an effect on one’s energy ﬁeld, is controversial and lies in doubt.
—Cochrane Review of Touch Therapies, quoted here
Science is advanced by an open mind that seeks knowledge, while acknowledging its current limits. Science does not make assertions about what cannot be true, simply because evidence that it is true has not yet been generated. Science does not mistake absence of evidence for evidence of absence. Science itself is fluid.
When people became interested in alternative medicines, they asked me to help out at Harvard Medical School. I realized that in order to survive there, one had to become a scientist. So I became a scientist.
—Ted Kaptchuk, quoted here.
…It seems that the decision concerning acceptance of evidence (either in medicine or religion) ultimately reflects the beliefs of the person that exist before all arguments and observation.
—Ted Kaptchuk, quoted here.
Together they betray a misunderstanding of science that is common not only to “CAM” apologists, but to many academic medical researchers. Let me explain. (more…)
In writing about science-based medicine, we give a lot of attention to medicine that is not based on good science. We use bad examples to show why science is important and how it is frequently misapplied, misinterpreted, misreported, or even wholly rejected. It’s a pleasure, for a change, to write about a straightforward example of the best of science-based medicine in action. The book Heart 411 is such an example.
The medical literature is a jungle of conflicting and complicated studies. It’s difficult for novices and even for sophisticated non-specialists to navigate. It’s useful to have experts as guides who can apply their knowledge, experience, and judgment to analyze the data and put everything into perspective. I can’t imagine anyone more qualified as guides to “matters of the heart” than the authors of this book. Heart surgeon Marc Gillinov and cardiologist Steven Nissen practice at the Cleveland Clinic, which has been ranked as the number one heart hospital by U.S. News & World Report for the last 15 years and is currently ranked 4th best hospital overall. They have treated more than 10,000 heart patients over 30 years of clinical practice and have also done extensive research and published hundreds of articles in peer reviewed journals. Their book contains everything they would like their patients to know about the prevention, diagnosis, and treatment of heart disease. It amounts to an owner’s manual for the heart. (more…)
A Loose End
In the last post I wondered if Ted Kaptchuk, when he wrote the article titled “Effect of interpretive bias on clinical research,” had understood this implication of Bayes’s Theorem: that interpretations of most scientific investigations are exercises in inverse probability, and thus cannot logically be done without consideration of knowledge external to the investigation in question. I argued that if Kaptchuk had
…understood the point when he wrote his treatise, he was dishonest in not explaining it and in not citing at least one pertinent article, such as Steven Goodman’s (which I’m willing to bet he had read). If he didn’t understand the point he should have withheld his paper.
In researching more of Kaptchuk’s opinions I’ve discovered that he had certainly read Goodman’s article, but that he either didn’t understand it or preferred to obscure its implications in deference to his ongoing project in belittling scientific knowledge. In a letter to the editor of the Annals of Internal Medicine in 2001, Kaptchuk opined that even if “more trials of distant healing with increased methodologic rigor” were positive, it still would not “be persuasive for the medical community”:
The situation resembles the predicament with homeopathy trials, another seemingly implausible intervention, where the evidence of multiple positive randomized, controlled trials will not convince the medical community of its validity. Additional positive trials of distant healing are only likely to further expose the fact that the underpinning of modern medicine is an unstable balance between British empiricism (in the tradition of Hume) and continental rationalism (in the tradition of Kant).
…It seems that the decision concerning acceptance of evidence (either in medicine or religion) ultimately reflects the beliefs of the person that exist before all arguments and observation. [Kaptchuk cites the second of the two Goodman articles that I referred to above, discussed here]
“Strong Medicine”: Ted Kaptchuk and the Powerful Placebo
At the beginning of the first edition of The Web that has no Weaver, published in 1983, author Ted Kaptchuk portended his eventual academic interest in the placebo:
A story is told in China about a peasant who had worked as a maintenance man in a newly established Western missionary hospital. When he retired to his remote home village, he took with him some hypodermic needles and lots of antibiotics. He put up a shingle, and whenever someone came to him with a fever, he injected the patient with the wonder drugs. A remarkable percentage of these people got well, despite the fact that this practitioner of Western medicine knew next to nothing about what he was doing. In the West today, much of what passes for Chinese medicine is not very different from the so-called Western medicine practiced by this Chinese peasant. Out of a complex medical system, only the bare essentials of acupuncture technique have reached the West. Patients often get well from such treatment because acupuncture, like Western antibiotics, is strong medicine.
Other than to wonder if Kaptchuk had watched too many cowboy ‘n’ Native American movies as a kid, when I first read that passage I barely blinked. Although the Chinese peasant may have occasionally treated someone infected with a bacterium susceptible to his antibiotic, most people will get well no matter what you do, because most illnesses are self-limited. Most people feel better even sooner if they think that someone with special expertise is taking care of them. If you want to call those phenomena the “placebo effect,” in the colloquial sense of the term, fine. That, I supposed, was what Kaptchuk meant by “strong medicine.”
Turns out I was mistaken. Let’s briefly follow Kaptchuk’s career path after 1983. In the 2000 edition of The Web, he wrote: