Bordetella pertussis is the bacterium that causes whooping cough – the main clinical feature of which is a severe lingering cough that can last for weeks or even months. Right now we are in the midst of an epidemic of pertussis cropping up in pockets throughout the US, most notable California. According to the CDC:
During January 1– June 30, 2010, a total of 1,337 cases were reported, a 418% increase from the 258 cases reported during the same period in 2009. All cases either met the Council of State and Territorial Epidemiologists definitions for confirmed or probable pertussis or had an acute cough illness and Bordetella pertussis–specific nucleic acid detected by polymerase chain reaction from nasopharyngeal specimens.
In addition, if the trends continue through the end of this year, which they are likely to do, this will be the highest incidence of pertussis in almost 50 years. These numbers are not in question, but there is some discussion about what, exactly, is causing it.
There is an interesting controversy raging in the Multiple Sclerosis (MS) world that reflects many of the issues we discuss at science-based medicine. Dr. Paolo Zamboni, and Italian vascular surgeon, has now published a series of studies claiming that patients with clinically defined MS have various patterns of chronic cerebrospinal venous insufficiency (CCSVI). Further Dr. Zamboni believes CCSVI is a major cause of MS, not just a clinical side-consequence, and is exploring treatment with venous angioplasty or stenting.
The claims have captured the attention of MS patients, many of whom have a progressive course that is only partially treated by currently available medications. There are centers popping up, many abroad (such as India), providing the “liberation procedure” and anecdotes of miraculous cures and spreading over the internet. There is even a Facebook page dedicated to CCSVI, and you can read the anecdotes for yourself. Many profess dramatic improvement immediately following the procedure, which seems unlikely even if Zamboni’s hypothesis is correct.
Zamboni is also getting attention from neurologists and MS specialists, who remain skeptical because Zamboni’s claims run contrary to years of research and thousands of studies pointing to the current model of MS as an autoimmune disease.
Here is the conclusion quoted from a recent New England Journal of Medicine (NEJM) review article on acupuncture for back pain:
As noted above, the most recent wellpowered clinical trials of acupuncture for chronic low back pain showed that sham acupuncture was as effective as real acupuncture. The simplest explanation of such findings is that the specific therapeutic effects of acupuncture, if present, are small, whereas its clinically relevant benefits are mostly attributable to contextual and psychosocial factors, such as patients’ beliefs and expectations, attention from the acupuncturist, and highly focused, spatially directed attention on the part of the patient.
Translation – acupuncture does not work. Why, then, are the same authors in the same paper recommending that acupuncture be used for chronic low back pain? This is the insanity of the bizarro world of CAM (complementary and alternative medicine). Yesterday David covered the same article, which I had also covered on NeuroLogica, but we both thought this issue important enough to document our thoughts and objections on SBM.
A new study published in The American Journal of Clinical Nutrition is reporting an association with eating meat and weight gain. This is a fairly robust epidemiological study, but at the same time is a good example of how such information is poorly reported in the media, leading to public confusion.
The data is taken from the European Prospective Investigation into Cancer and Nutrition–Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home and Obesity (EPIC-PANACEA) project. This is a long term epidemiological study involving hundreds of thousands of individuals, and is therefore a great source of data. We are likely to see many publications from from it. This one looked at the association of meat eating – poultry, red meat, and processed meat – with total weight. From the methods:
A total of 103,455 men and 270,348 women aged 25–70 y were recruited between 1992 and 2000 in 10 European countries. Diet was assessed at baseline with the use of country-specific validated questionnaires. A dietary calibration study was conducted in a representative subsample of the cohort. Weight and height were measured at baseline and self-reported at follow-up in most centers. Associations between energy from meat (kcal/d) and annual weight change (g/y) were assessed with the use of linear mixed models, controlled for age, sex, total energy intake, physical activity, dietary patterns, and other potential confounders.
Homeopathy is having a bad year. From a scientific point of view, it has had a couple of bad centuries. The progress of our scientific understanding of biology, chemistry, and physics has failed to confirm any of the core beliefs of homeopathy. Like does not cure like (this is a form of superstition known as sympathetic magic, with no basis in science). Diluting substances does not make them stronger – a notion that violates the chemical law of mass action and the laws of thermodynamics. And countless clinical studies have shown that homeopathic preparations are nothing more than placebos. That homeopathy cannot work and does not work is settled science, as much as it is possible for science to be settled.
Despite the science, homeopathy has persevered through a combination of cultural inertia and political support. But in the last year there are signs that this trend may be reversing. In the UK The House of Commons Science and Technology Committee (STC) released a report, Evidence Check 2: Homeopathy, in which they conclude that homeopathy is failed science and should be completely abandoned – no further support in the NHS and no further research.
Following that the British Medical Association has openly called for an NHS ban on homeopathy, calling the practice “witchcraft.”
Now German politicians are starting to echo the same sentiments. (more…)
One of my goals in writing for this blog is to educate the general public about how to evaluate a scientific study, specifically medical studies. New studies are being reported in the press all the time, and the analysis provided by your average journalist leaves much to be desired. Generally, they fail to put the study into context, often get the bottom line incorrect, and then some headline writer puts a sensationalistic bow on top.
In addition to mediocre science journalism we also face dedicated ideological groups who go out of their way to spin, distort, and mutilate the scientific literature all in one direction. The anti-vaccine community is a shining example of this – they can dismiss any study whose conclusions they do not like, while promoting any horrible worthless study as long as it casts suspicion on vaccines.
Yesterday on Age of Autism (the propaganda blog for Generation Rescue) Mark Blaxill gave us another example of this, presenting a terrible pilot study as if we could draw any conclusions from it. The study is yet another publication apparently squeezed out of the same data set that Laura Hewitson has been milking for several years now - a study involving macaque infants and vaccinations. In this study Hewitson claims a significant difference in brain maturation between vaccinated and unvaccinated macaque infants, by MRI and PET analysis. Blaxill presents the study without noting any of its crippling limitations, and the commenters predictably gush.
Last week at TAM8 some SBM colleagues (David Gorski, Kimball Atwood, Harriet Hall, Rachel Dunlop) and I gave two workshops on how to find reliable health information on the web. As part of my research for this talk I came across a recent and interesting study that I would like to expand upon further – Quality and Content of Internet-Based Information for Ten Common Orthopaedic Sports Medicine Diagnoses.
The fact that the article focuses on orthopedic diagnoses is probably not relevant to the point of the article itself, which was to assess the accuracy of health information on the web. They looked at 10 orthopedic diagnoses and searched on them using Google and Yahoo, and then chose the top results. They ultimately evaluated 154 different sites with multiple reviewers for quality of content and also for their HON rating.
For background, the HON rating comes from an independent organization, the Heath on the Net Foundation, that rates health care sites on a number of criteria. These include assessment of how authoritative the sources are, the level of transparency, and if opinions expressed are justified with evidence and references. While generally reasonable, the HON assessment does not necessarily involve a thorough assessment of the quality of the science on a given website, and many sites with what I would consider dubious information have earned the HON seal of approval.
Last year Ben Kavoussi published an interesting article on SBM called Astrology with Needles in which he purported a historical connection between acupuncture and bloodletting. I had previously thought that bloodletting was a uniquely Western cultural invention – part of Galenic medicine involving the balancing of the four humors, one of which being blood. (In the West bloodletting faded away with the advent of science-based medicine in the 19th century.) I was intrigued by this connection and have since been doing my own reading on the topic. It turns out that bloodletting was common throughout ancient cultures and not unique to the west.
In fact acupuncture was originally a form of bloodletting – the “needles” were really lances and the acupuncture points locations over veins to be opened. Chi, or the Chinese concept of the life force, was believed to be partly in the blood, and blood letting could be used to free the flow of chi. This was closely related to the Galenic concept of using bloodletting to free the flow of static blood in the tissue.
For example, in the ancient medical text of Suwen, we find:
When heaven is warm and when the sun is bright,
then the blood in man is rich in liquid
and the protective qi is at the surface
Hence the blood can be drained easily, and the qi can be made to move on easily…
Mark Hyman, a proponent of so-called “functional medicine” promoting himself over at the Huffington Post (an online news source that essentially allows dubious medical infomercials to pass as news) has posted a particularly egregious article on personalized medicine for dementia. In the article Hyman distorts the modern practice of medicine, the current state of genetic science, and the very notion of “disease.” It is, as usual, a fine piece of medical propaganda sure to confuse many a reader.
Hyman starts with some standard epidemiology of dementia – it is a common and growing disorder – but then descends quickly into distortion and pseudoscience.
Conventional Medicine Strawman.
Hyman creates what readers are likely to recognize by now as the standard straw man of conventional or science-based medicine, and then uses that caricature to create a false dichotomy with his “functional” medicine. He writes:
The International Society for Stem Cell Research (ISSCR) is a professional organization of stem cell researchers. I am happy to see that they see it as their responsibility to respond to the growth of dubious stem cell clinics offering unproven treatments to desperate patients.
In a recently published handbook for patients, they write:
The International Society for Stem Cell Research (ISSCR) is very concerned that stem cell therapies are being sold around the world before they have been proven safe and effective.
Stem cell therapies are nearly all new and experimental. In these early stages, they may not work, and there may be downsides. Make sure you understand what to look out for before considering a stem cell therapy.
Remember, most medical discoveries are based on years of research performed at universities and companies. There is a long process that shows first in laboratory studies and then in clinical research that something is safe and will work. Like a new drug, stem cell therapies must be assessed and meet certain standards before receiving approval from national regulatory bodies to be used to treat people.
This is good advice for any new treatment.