The carotid artery in the neck is a common site of atherosclerosis. As plaque builds up, it leaves less room for blood flow and can cause strokes through clotting or embolization. Carotid stenosis is defined as a greater than 70% narrowing of the lumen (the space through which the blood flows in an artery). It can cause symptoms, including transient ischemic attacks (TIAs) and minor strokes; but it is frequently asymptomatic. It can be treated with carotid endarterectomy (CEA) or carotid angioplasty and stenting (CAAS). There has been much discussion about which procedure is better and when it is better not to do either. (more…)
Ponce de Leon is said to have been looking for the Fountain of Youth when he explored Florida. That’s only a myth. Now there’s a new myth, that testosterone supplements are a Fountain of Youth for aging men. Men are urged to get their testosterone levels checked if they have any of a long laundry list of vague symptoms. Anti-aging clinics promote testosterone supplementation in many forms: prescription, bioidenticals from compounding pharmacies, natural remedies, testosterone boosters, and precursors. There are highly inflated estimates of the number of men who need supplementation, often relying on broadened criteria for diagnosis or non-standard lab tests. Testimonials abound: “My depression symptoms disappeared in 20 minutes when I started using Androgel.” (That one’s particularly hard to believe. Suggestion can be powerful.)
Until recently, evidence for the benefits of testosterone supplements was scanty, and there was concern about increased cardiovascular and prostate risks and other side effects. A 2013 study found that while testosterone was clearly indicated for younger men with classic hypogonadism caused by known diseases, a general policy of testosterone replacement in all older men with age-related decline in testosterone levels was not justified. In 2003 an Institute of Medicine panel called for a set of coordinated clinical trials to determine whether testosterone would benefit older men who had low testosterone levels for no known reason other than age and who had clinical conditions to which low testosterone might contribute. The results of those trials are starting to come in. The findings to date were covered in an article in the New England Journal of Medicine in February 2016. The full text is available online.
Last year I reviewed Tomasz Witkowski and Maciej Zatonski’s book Psychology Gone Wrong where they pointed out that many of psychology’s accepted beliefs and therapies were not based on good evidence. Now Witkowski has written a new book, to be published later this year, Psychology Led Astray: Cargo Cult in Science and Therapy, that is certain to ruffle a lot of feathers. He compares psychology to cargo cults. He says, “the cargo cult phenomenon is virtually absent in physics, chemistry, and mathematics, yet it runs rampant in both psychology and sociology.” He uncovers cargo cult practices in psychology, unmasking therapies that are devoid of science, dangerous, and even cruel, especially those directed at children.
Richard Feynman was the first to compare the contemporary social sciences, including psychology, to a cargo cult. For those not familiar, the term “cargo cult” originates with the natives in Melanesia, who were awestruck by the planes that landed on their islands during WWII bringing all kinds of supplies. They had no understanding of what airplanes were or where they came from. Magical thinking led them to create bamboo replicas of planes and control towers in the superstitious belief that it would attract planes and bring them material goods. Similarly, many psychology researchers have been imitating the methods of science without really understanding how science is supposed to work. They go through the motions, but their research designs are so poorly thought out and the methodology so poor that their results are meaningless. And then they use those meaningless results to guide therapy. They have been led astray, have deceived themselves, and have harmed patients. (more…)
A recent article in The New England Journal of Medicine by Andrew L. Mammen, MD, PhD, reviewed statin-associated myopathies. Reading his article prompted me to revisit the subject of statin side effects.
It can no longer be disputed that statins statistically benefit patients who have cardiovascular disease or who are at high risk of cardiovascular disease. But there are still disputable issues. Which patients should be treated? The recent treatment guidelines have been widely criticized. And the actual magnitude of the benefit is small, although we know the benefits are greater for patients at higher risk. It has been argued that as many as 99% of patients who take statins will take them unnecessarily, risking side effects for no benefit. The problem is that we can’t identify which patients those are. Until we learn more, we are stuck treating the many to help the few. As with any medication, there are risks to be balanced against the benefits. What do we really know about the side effects of statins?
Lots of anecdotes, conflicting evidence
It’s very hard to pin down the truth. The Internet is full of anecdotal reports of devastating side effects from statin drugs, including cancer, dizziness, depression, anemia, acidosis, pancreatitis, cataracts, heart failure, hunger, nausea, sleep problems, memory loss, ringing in the ears, “a sense of detachment,”… the list goes on. When symptoms such as these have been evaluated in controlled studies, they have not been shown to occur more often with the drug than with placebo.
The doubling time for E.coli bacteria is 20 minutes. With uncontrolled growth, it would take a mere two days for the weight of bacteria to equal the weight of the Earth. What rules determine the actual numbers of bacteria? Why is the world green; why don’t insects eat all the leaves? How does the body maintain homeostasis? What determines the uncontrolled growth of cancers? What happens when you remove natural predators from an ecosystem?
You can find the answers in Sean Carroll’s new book The Serengeti Rules: The Quest to Discover How Life Works and Why It Matters.
Everything is regulated: every kind of molecule, cell, and process in the body is maintained in a specific range and governed by a specific substance or set of substances. Diseases are mostly abnormalities of regulation. Too little insulin = diabetes. Uncontrolled cell multiplication = cancer. To intervene in disease, we need to understand the rules of regulation.
Carroll calls them the Serengeti Rules because of the ecological rules that regulate the predator/prey ratios in Africa. But the same rules apply everywhere, at every level of biology. (more…)
My local newspaper is a constant source of topics to blog about. It regularly features ads for untested dietary supplements and for chiropractors who offer non-chiropractic treatments and don’t identify themselves as chiropractors. Recently, a full-page ad for NW Pain Relief Centers trumpeted “Stem Cell Technology Takes Joint Treatment to the Next Level.” It said stem cell treatments could heal and regenerate tissue in conditions such as knee osteoarthritis, carpal tunnel, peripheral neuropathy, spinal stenosis, hip pain, and tendinitis. A table titled “Consider these facts” compared stem cell therapy to surgery, saying stem cell treatments involve no known side effects, little or no pain, and immediate recovery; whereas surgery involves complications, poor outcomes, addiction to pain medications, severe pain for months, and a prolonged recovery over months and years. It said, “Call now if you experience any degree of joint pain or discomfort…Space is limited to the first 30 callers!”
A few days later there was another full-page ad for NW Pain Relief Centers, this time for hyaluronic acid injections into the knee for osteoarthritic knee pain. It reprinted the same table of comparisons with surgery, with an additional line comparing costs (that didn’t actually compare costs, but only vaguely mentioned insurance coverage, deductibles, copays, and time off work. It featured the same “Call now, space limited” ploy.
These ads reminded me so much of chiropractic ads that I had to wonder what was going on. They mentioned an “allied team of health professionals.” I guessed there must be at least one MD on their team if they were injecting stem cells and hyaluronic acid into joints. I guessed chiropractors were a prominent part of the team. I guessed right. (more…)
It dates back at least to Galileo. A scientist finds evidence that contradicts a cherished popular belief. Instead of a rational examination of his evidence, he is subjected to vicious personal attacks. Alice Dreger examines the phenomenon in her book Galileo’s Middle Finger: Heretics, Activists, and the Search for Justice in Science. She is eminently qualified to do so. She is a professor of clinical medical humanities and bioethics, a historian, a gifted writer, an activist for patient rights, and an indefatigable investigative journalist who has herself been a victim of the kind of persecution she describes.
The histories she recounts are horrifying. She gives example after example of activists using lies and personal attacks to suppress evidence they don’t like. She reveals dirty linen in the most unexpected places. (more…)
The Puritan’s Pride website has a Vitamin Advisor that claims to provide a personalized supplement plan, with expert recommendations chosen just for you. In my opinion it is deceptive, designed not to provide evidence-based personalized health advice, but to sell their products; and one can only wonder what kind of “experts” would support such ill-advised recommendations. Stephen Barrett and I have just co-authored an article on the Quackwatch site analyzing the Vitamin Advisor’s advice. I wanted to share what we found with our SBM readers, with some further comments.
Their recommendations are based on a series of questions like age, sex, health concerns, whether you are exposed to cigarette smoke, etc. The full list can be found in our Quackwatch article. The one-size-fits-all questions are useless because “eye concerns” might mean anything from needing glasses to glaucoma. (more…)
When I was pregnant, I obediently took the iron pills and prenatal vitamins prescribed by my obstetrician. And I prescribed them for every pregnant patient I took care of as a family physician. I never questioned the practice. It seemed intuitively obvious that it was a good thing; we know pregnancy makes extra nutritional demands and depletes iron stores. It never occurred to me to question what I had been taught, because it seemed perfectly logical. I did question other things I was taught that didn’t seem so logical. In my internship, we were ordered to do episiotomies on every patient (the rationale was that it made birth less traumatic for the baby and prevented uncontrolled perineal tearing in the mother). I was severely chastised for omitting an episiotomy on a patient who begged me not to do one. She had had several babies and was stretchy enough to deliver easily without an episiotomy. In this case, my common-sense clinical judgment was vindicated by further research in the years after my internship; new evidence showed that routine episiotomies were of no benefit, practice changed in response to the new evidence, and episiotomies are no longer done routinely.
That was a long time ago. I have long since learned that even the most reasonable assumptions can be wrong. I happened to be right about episiotomies, but I might just as well have been wrong; and the only way to know whether a belief is true is to test it in controlled scientific trials. As Will Rogers said, “It isn’t what we don’t know that gives us trouble, it’s what we know that ain’t so.” It turns out that routine multivitamin and iron supplementation is not supported by any convincing evidence from scientific studies. And practice is changing. Recently, when one woman asked her OB what she should do about prenatal vitamins he pulled his wastebasket out from under his desk and said “put them there.” (more…)
In a recent post, Dr. Gorski criticized two articles by Jo Marchant on placebos and alternative medicine. He mentioned that she had a book coming out and suggested I might want to review it. The title is Cure: A Journey into the Science of Mind Over Body.
I don’t know of any evidence that the mind has ever cured a disease, so I would have been prejudiced against this book just from its title, and Dr. Gorski’s post prejudiced me even more. But I was willing to give it a fair trial. The publisher sent me a review copy of the book and I read it. I was expecting to hate it, but I was pleasantly surprised. I enjoyed reading it. I found it fascinating. I found myself agreeing with much of what Marchant says, and I was intrigued by some of the recent research she reports that I was not yet aware of. Preliminary studies, to be sure, but thought-provoking. The book challenged me to think more deeply about placebos, alternative medicine, and patient comfort. (more…)