There is a very good chance that you will feel worse after seeing a chiropractor.
According to a new systematic review, serious complications of spinal manipulation are rare, but 33-60% of patients experience milder short-term adverse effects such as increased pain, radiation of pain, headaches, vertigo and even loss of consciousness. The study, published in the journal Spine, involved searching PubMed and the Cochrane Library for the years 1966 to 2007. They identified additional studies by hand searching. They looked for all articles that reported adverse effects associated with chiropractic irrespective of type of design. They omitted any reports where patients had underlying diseases (osteogenesis imperfecta, expansive vertebral hemangioma, osteoporotic fracture, etc.) that predisposed them to complications with manipulation.
They found 46 pertinent studies:
- One randomized controlled trial
- Two case-control studies
- Six prospective studies
- Twelve surveys
- Three retrospective studies
- 115 case reports
They recognized that “the heterogeneity of the study designs did not allow conducting a formal meta-analysis.” But they did the best they could to make sense out of what they found. (more…)
Unfortunately, a frequent topic on SBM has been the anti-vaccine movement, personified these days by celebrity spokesmodel for Generation Rescue Jenny McCarthy and her dimmer than dim boyfriend comedian and actor Jim Carrey. Unfortunately, it is a topic that is unlikely to go away. We’ve all speculated why the anti-scientific emotion-based notion that vaccines somehow must cause autism persists in spite of mountains of evidence to the contrary, but I think the question goes much deeper than that because it’s not just about vaccines. The anti-vaccine movement is but one of the most visible components of a much deeper problem in our public discourse, a problem that values feelings and personal experience over evidence, compelling stories and anecdotes over science.
I’m referring to the Oprah-fication of medicine in America.
An Anesthesiologist’s Perspective
The late John Bonica (1917-1994), one of the great anesthesiologists of the 20th century, has been called “The Founding Father of the Pain Field.” He developed this interest while treating wounded soldiers at Fort Lewis, Washington, during WW II. Shortly thereafter he became a pioneer of epidural analgesia and other forms of safe pain relief for labor and delivery. In 1947 he created the first multidisciplinary pain clinic, at Tacoma General Hospital, and in 1960 brought it to the University of Washington School of Medicine when he became the founder and first chairman of its Department of Anesthesiology. In 1953 he published the first comprehensive textbook on the subject of pain, the 1500 page Management of Pain. In 1973 he founded what is now the largest professional organization devoted to pain relief, the International Association for the Study of Pain (IASP).
Dr. Bonica was born in Italy. He came to New York City with his family when he was 11. His father died four years later and he became the major breadwinner for the family. He competed in wrestling while in high school and won both the New York City and state championships. Later he worked his way through college and medical school by wrestling professionally under the pseudonym ‘Johnny (Bull) Walker’, and according to several sources he was the “Light Heavyweight Wrestling Champion of the World.” He continued to wrestle while in the army but concealed his military identity by becoming, in the ring, the “Masked Marvel.”
At the time of the burgeoning Western interest in acupuncture in the early 1970s, Dr. Bonica became the Chairman of the Ad Hoc Committee on Acupuncture of the National Institutes of Health (NIH). In 1973 he was “selected by the Committee on Scholarly Communication with the People’s Republic of China of the National Academy of Sciences to be a member of the first official American medical delegation to visit the People’s Republic of China, and was given the responsibility of evaluating acupuncture and anesthesia as practiced in that country.”
In the three prior posts of this series I tried to analyze some of the defects in the randomized clinical rials (RCTs) of homeopathic remedies for childhood diarrhea. The first entry showed that the first two RCTs’ (done in Nicaragua) methods could not produce a meaningful result because of the way the RCTs were set up (methods.) The second entry showed that the results obtained in the first two trials were meaningless clinically even if assumed to have resulted from more legitimate methods. The same applied to the third trial in Nepal, analyzed in the third entry.
This entry will suggest that the authors’ fourth paper (Jacobs J, Jonas WB, Jimenez-Perez M, Crothers D. Homeopathy for childhood diarrhea: combined results and metaanalysis from three randomized, controlled clinical trials. Pediat Inf Dis J, 2005;22:229-234.)- a meta-analysis (MA) of the data from the three RCTs resulted in conclusions equally as meaningless as those of the three trials.
The MA authors – several of the same workers from the three RCTs – begin by agreeing that the data from the RCTs, taken individually, were of borderline significance:
In our previous three studies, we evaluated the use of individualized homeopathic treatment of childhood diarrhea … The results of the two larger studies (n = 81, n = 116) were just at or near level of statistical significance. Because all three studies followed the same basic study design , […] we analyzed the combined data from these three studies to obtain greater statistical power. In addition we conducted a meta-analysis of effect-size difference […] to look for consistency of effects.
MAs and systematic reviews (SRs) are the two consensus methods for summarizing data from multiple individual studies. The inclusion and search methods of RCTs for SRs and MAs are similar, but the objectives of the two are a bit different, as are the forms of the reports. In SRs, the results are summarized in more in narrative form, whereas in MAs the data are treated mathematically and the results are defined in statistical terms. Thus authors of SRs are freer to speculate on the degree of confidence that a method is effective based on what is shown by the numbers of positive and negative RCTs collected. Authors of MAs usually limit their comments to what the mathematical formulation of the summarized data show.
An audience member at a recent NYC Skeptics meeting asked me how I handled conflict surrounding strongly held beliefs that are not supported by conclusive evidence. As a dentist, he argued, he often witnessed professionals touting procedure A over procedure B as the “best way” to do X, when in reality there are no controlled clinical trials comparing A and B. “How am I to know what’s right in these circumstances?” He asked.
And this is more-or-less what I said:
The truth is, you probably can’t know which procedure is better. At least, not at this point in history. The beauty of science is that it’s evolving. We are constantly learning more about our bodies and our environment, so that we are getting an ever-clearer degree of resolution on what we see and experience.
It’s like having a blurry camera lens at a farm. At first we can only perceive that there are living things moving around on the other side of the lens – but as we begin to focus the camera, we begin to make out that the animals are in the horse or cattle family. With further focus we might be able to differentiate a horse from a cow… and eventually we’ll be able to tell if the horse has a saddle on it, and maybe one day we’ll be able to see what brand of saddle it is. Each scientific conundrum that we approach is often quite blurry at the onset. People get very invested in their theories of the presence or absence of cows, and whether or not the moving objects could in fact be horses. Others say that those looking through the camera contradict one another too much to be trusted – that they must be offering false ideas or willfully misleading people about the picture they’re describing.
In fact, we just have different degrees of clarity on issues at any given point in time. This is not cause for alarm, nor is it a reason to abandon our cameras. No, it just gives us more reason to continue to review, analyze, and revise our understanding of the picture at hand. We should try not to make more out of photo than we can at a given resolution – and understand that contradicting opinions are more likely to be evidence of insufficient information than a fundamental flaw of the scientific method.
The Centers for Disease Control (CDC) currently recommends that children 6 month to 18 years old receive an annual flu vaccine. There are two types of flu vaccines used in the US: a live attenuated virus (LAIV) and a trivalent inactivated virus (TIV) vaccine. Both are safe and effective – while efficacy varies from year to year, they are 70-90% effective in healthy adults. Efficacy is young children appears to be slightly less, about 66%.
There remains, however, many sub-questions about the flu vaccines and by the time researchers have thoroughly explored them vaccine technology is likely to have progressed, and therefore any new vaccines will have to be tested all over again.
One of those sub-questions about vaccine safety and efficacy is the net effect of the flu vaccine in children with asthma. Some have raised concerns that the vaccine may exacerbate asthma, a 1-2% increased wheezing and 3% increased hospitalizations have been reported, although so far the bulk of the data suggests that both types of flu vaccines are safe in children with asthma. There is evidence to suggest that the LAIV may be superior to the TIV in children, particularly with asthma.
Last month I wrote about a book on evolutionary medicine that I could not recommend. Now I’ve found one I can recommend. Marlene Zuk, an evolutionary biologist at the University of California, Riverside, has written a delightful book entitled Riddled with Life: Friendly Worms, Ladybug Sex, and the Parasites That Make Us Who We Are. She describes how our parasites and diseases co-evolved with us: as we developed better defenses, they developed better weapons. “We do not choose to have them, but our lives are unimaginable without them, and for better or worse, they have made us who we are.” Parasites have altered our bodies in ways that science fiction filmmakers could never have imagined. She even suggests that we can thank parasites for the fact that we reproduce sexually rather than asexually.
She advocates an evolutionary medicine that “places diseases and defects in an evolutionary framework to make sense of the apparent mismatch between the way our bodies often work and the way we would like them to.” Evolution did not design our bodies for health, but to maximize reproduction.
“Just because our species evolved in a different environment does not mean …that following the ways of the past is automatically going to free us from the illnesses of modern life.” She incisively debunks the myth of the Paleolithic diet and points out that if we wanted to copy our hunter-gatherer ancestors we would have no way of deciding which ones to copy – the ones from 10,000 years ago or the ones from 100,000 years ago; the Inuits or the Kalahari Bushmen. She also points out that evolution explains why humans vary and why one diet won’t suit everyone. (more…)
We’ve written a lot about anti-vaccine zealotry on this blog, as Steve and I take a particular interest in this particular form of dangerous pseudoscience for a number of reasons. One reason, of course, is that the activities of antivaccine groups like Generation Rescue and its spokesmodel since 2007 (Jenny McCarthy, a frequent topic on this blog) have started to frighten parents about vaccines enough that vaccination rates are falling well below that required for herd immunity in some parts of the country. Indeed, McCarthy, at the behest of her handlers in Generation Rescue, serves up a regular “toxic” brew of misinformation and nonsense about vaccines, most recently in a video that was the subject of a post by Val Jones about her unbelievably pseudoscience-laden blather. Truly, it has to be seen to be believed. Meanwhile, Generation Rescue has sent McCarthy on a media propaganda tour for her latest antivaccine pro-quackery book and set up a misinformation-laden propaganda site called Fourteen Studies (blogged about by Steve Novella, Mark Crislip, and, of course, yours truly) in which they attack well-designed studies that have failed to confirm their pet idea that somehow, some way, vaccines must be the cause of autism. And, when their pseudoscience is criticized, the antivaccine movement has a tendency to launch vicious ad hominem attacks, as they recently did against Steve Novella and have done multiple times in the past against me.
However, there is one other consequence of the antivaccine movement, however, and it is at least as important as the public health implications of the potential dimunition of herd immunity caused by the fear mongering of groups like Generation Rescue. That consequence is the cottage industry of “biomedical” treatments to which desperate parents subject their children. Gluten-free diets, chelation therapy (which has caused deaths), hyperbaric oxygen chambers (a recent story described a child getting severely burned when one of these caught fire), autistic children have been subjected to it all. But of all the biomedical woo to which autistic children have been subjected, one form of woo stands out as being particularly heinous. Indeed, I agree with our fearless leader Steve in characterizing it as an “atrocity.”
I’m referring to Mark and David Geier’s favored “treatment” for autistic children, namely a drug called Lupron.
It had once been suggested in the comments section of the blog that homeopathy is useful in the treatment of diseases that are not self limited. Homeopathy is effective therapy for diseases that do not get better on their own, that homeopathy has a real effect on real diseases.
One example given was for the treatment of sepsis.
“Frass M, Linkesch, M, Banjya, S, et al. Adjunctive homeopathic treatment in patients with severe sepsis: a randomized, double-blind, placebo-controlled trial in an intensive care unit. Homeopathy 2005:94;75–80. At a University of Vienna hospital, 70 patients with severe sepsis were enrolled in a randomized double-blind, placebo-controlled clinical trial, measuring survival rates at 30 days and at 180 days. Those patients given a homeopathic medicine were prescribed it in the 200C potency only (in 12 hour intervals during their hospital stay). The survival rate at day 30 was 81.8% for homeopathic patients and 67.7% for those given a placebo. At day 180, 75.8% of homeopathic patients survived and only 50.0% of the placebo patients survived (p=0.043). One patient was saved for every four who were treated.”
I am, as I have mentioned before, but I mention again for those who might be new to the blog, an Infectious Disease physician. My job is to diagnosis and treat infectious diseases and sepsis is up there at the top of the list of diseases I take of. Sepsis butters my bread, and I consider myself knowledgeable about sepsis.
I’ve been fairly quiet about Jenny McCarthy’s campaign against childhood vaccinations, partly because Dr. David Gorski has covered the issue so thoroughly already, and partly because of my “do not engage” policy relating to the deeply irrational (i.e. there’s no winning an argument with “crazy.”) But this week I was filled with a renewed sense of urgency regarding the anti-vaccinationist movement for two reasons: 1) I received a personal email from a woman who is being treated with hostility by her peers for her pro-science views on vaccines and 2) a friend forwarded me a video of Jenny McCarthy speaking directly to moms, instructing them to avoid vaccinating their kids or giving them milk or wheat because of their supposed marijuana-like addictive properties.