Posts Tagged H. pylori
In 1850, one in four American babies died before their first birthday, and people of all ages died of bacterial infections that could have been successfully treated today with antibiotics. Unfortunately, treatments that have effects usually have side effects, and we are seeing problems due to the overuse of antibiotics. They are given to people with viral infections for which they are useless and to food animals to improve their growth. As a result, antibiotic-resistant organisms are evolving and the development of new antibiotics is not keeping up with the threat. This is common knowledge, but we’re starting to realize that there may be other problems with antibiotics even when they are used correctly to save lives.
The rates of obesity, diabetes, asthma, food allergies, hay fever, eczema, inflammatory bowel disease, celiac disease, acid reflux disease, and esophageal cancer are all on the rise. Martin Blaser, MD, director of the Human Microbiome Program at NYU, thinks antibiotics may be to blame, either as a causal or a contributing factor. In his book Missing Microbes: How the Overuse of Antibiotics Is Fueling Our Modern Plagues, he describes some of the fascinating research he and others have been doing to elucidate the role of the more than 100 trillion microbes that live on and in each of us, and the possibility that antibiotics may have a causal role in several of the so-called diseases of civilization. (more…)
One of the themes of SBM has been, since the very beginning, how the paradigm of evidence-based medicine discounts plausibility (or, perhaps more appropriately, implausibility) when evaluating whether or not a given therapy works. One of our favorite examples is homeopathy, a therapy that is so implausible on a strictly scientific basis that, for it to work, huge swaths of well-established science supported by equally huge amounts of experimental and observational evidence would have to be found to be all in serious error. While such an occurrence is not per se impossible, it is incredibly unlikely. Moreover, for scientists actually to start to doubt our understanding of chemistry, biochemistry, pharmacology, and physics to the point of thinking that our understanding of them is in such serious error that homeopathy is a valid description of reality, it would take a lot more than a bunch of low-quality or equivocal studies that show no effect due to homeopathy detectably greater than placebo.
On Friday, Kim Atwood undertook an excellent discussion of this very issue. What really caught my attention, though, was how he educated me about a bit of medical history of which I had been completely unaware. Specifically, Kim discussed the strange case of John Lykoudis, a physician in Greece who may have discovered the etiology of peptic ulcer disease (PUD) due to H. pylori more than a quarter century before Barry Marshall and Robin Warren discovered the bacterial etiology of PUD in 1984. One reason that this story intrigued me is the same reason that it intrigued Kimball. Lykoudis’ story very much resembles that of many quacks, in particular Nicholas Gonzalez, in that he claimed results far better than what medicine could produce at the time, fought relentlessly to try to prove his ideas to the medical authorities in Greece at the time, and ultimately failed to do so. Despite his failure, however, he had a very large and loyal following of patients who fervently believed in his methods. The twist on a familiar story, however, is that Lykoudis may very well have been right and have discovered a real, effective treatment long before his time.
After the previous posting on the Bayesian approach to clinical trial data, several new comments made it clear to me that more needed to be said. This posting addresses those comments and adds a few more observations regarding the unfortunate consequences of EBM’s neglect of prior probability as it applies to “complementary and alternative medicine” (“CAM”).†
The “Galileo gambit” and the statistics gambit
Reader durvit wrote:
A very interesting example, for a number of people, might be estimating the prior probability for Marshall and Warren’s early work on Helicobacter pylori and its impact on gastroduodenal management. I frequently have Marshall quoted to me as a variation on the Galileo gambit, so establishing whether he and Warren would have been helped or hindered by Bayesian techniques would be useful.
This suggestion raises a couple of issues. First, the “Galileo gambit” regarding Marshall and Warren’s discovery is a straw man (as durvit seems to have surmised). (more…)