When I wrote about colonoscopy in 2010, colonoscopy was thought to be the best screening test for colorectal cancer because it could visualize the entire colon and could remove adenomas that were precursors of cancer. But only fecal occult blood testing (FOBT) and sigmoidoscopy had been proven to decrease colorectal cancer incidence and mortality (by 16% and 28%, respectively). Observational evidence suggested that colonoscopy would reduce the incidence and the number of deaths from colorectal cancer, but there were no randomized controlled trials, and the reduction in incidence of cancer after colonoscopy screening seemed to be restricted to left-sided colon cancers, which didn’t make sense.
We still don’t have any randomized controlled trials of colonoscopy, but a 2013 case-control study from Germany compared patients with and without colorectal cancer and found that those who reported having had a colonoscopy were less likely to develop colon cancer for up to 10 years after the procedure. And now two studies published in the New England Journal of Medicine in September 2013 have shed more light on the subject.
Can neck manipulation cause strokes? Most MDs and many chiropractors agree that it can, but some chiropractors disagree. The subject has been covered on SBM before: here, here, here, here, here, here, here, here, and here. We keep returning to the subject not because it is a common problem (it isn’t), but because it is such a devastating one, and because the general public is still not aware of the risk.
A 2012 study published in the International Journal Of Clinical Practice “Assessing the risk of stroke from neck manipulation: a systematic review” concluded:
Conclusive evidence is lacking for a strong association between neck manipulation and stroke, but is also absent for no association.
Despite the uncertainty, they thought the association was strong enough to recommend informed consent be obtained and patients be warned that neck manipulation “may” increase the risk of a rare type of stroke.
A new study in the same journal, “Chiropractic and Stroke: Association or Causation?” applies Hill’s criteria of causation to the evidence and concludes that causality has not been determined. The author is Peter Tuchin, a senior lecturer in chiropractic at Macquarie University in Australia, and a known apologist for chiropractic. I agree with him that the existing evidence is inadequate to conclusively determine causality, but I think it supports a high probability of causality, and the alternate explanations he offers to exonerate chiropractors are questionable. And other factors should be considered, like the many “smoking gun” cases and whether there is any conclusive evidence of benefit to set against the possibility of risk. (more…)
There is a new book critical of chiropractic: Chiropractic Abuse: An Insider’s Lament. The author, Preston Long, DC, PhD, is a chiropractor who says he made a big mistake when he chose chiropractic as a career. He has written an intriguing book explaining his mistake and the experiences that resulted from it during 3 decades as a chiropractor and a critic of chiropractic.
Chiropractic encourages self-delusion, and those who break free of delusion have two choices: to fight or run. Preston Long chose to fight, to keep the baby and throw out the bathwater polluted with pseudoscience and quackery, to try to practice rationally and ethically, and to try to reform chiropractic from within. He soon learned that it was next to impossible for a chiropractor to make a living with a science-based, ethical practice. He eventually found his niche and put his knowledge of chiropractic to good use. He evaluates chiropractic cases for disability and fraud, has worked with the FBI, and has testified at over 200 trials. He has written two previous books, The Naked Chiropractor (2002) and The P.R.E.S.T.O.N. Protocol for Back Pain (2006). This new book tells the story of his life and exposes the delusions and misbehaviors of his chiropractic colleagues.
He reveals “20 things most chiropractors won’t tell you”: (more…)
Recently a correspondent asked me for advice about his parents. He said they use things like homeopathy, acupuncture, and copper bracelets. They use conventional medicine too, but it seems to be a 50/50 approach that gives each an equal weighting. He has tried to talk to them about things like homeopathy and the placebo effect, but the shutters come down hard and fast. He tries to criticize the alternative treatment itself without offending or attacking the person, but his mother still sees it as a personal attack. He worries that as they get older and in need of more medical care, his parents may not make the best decisions. He asks about how to tactfully have these conversations and perhaps change their point of view.
That’s a very tough question that gets asked a lot, and I don’t have any good answers; but I do have some thoughts and untested ideas that could serve as the starting point for a discussion, and I hope readers will pipe up in the comments and tell us what has or hasn’t worked for them. (more…)
Chiropractors would like to reinvent themselves as family doctors. I’ve written about that before and Jann Bellamy has written about it here, here, here, and here. A new study in The Journal of Chiropractic Education alleges that the National University of Health Sciences is nearing its institutional goal of training chiropractic students as primary care practitioners. The data they collected don’t even begin to support that assertion. The study is not only meaningless, it demonstrates a gross misunderstanding of the education required to practice competent primary care. (more…)
A friend asked me, “What do you know about biotin?”
I said, “Not much. Why do you ask?”
She explained that the woman who cuts her hair at the hair salon recommended she take biotin to strengthen her nails and improve hair growth. She tried it, and within a couple of months, her nails looked better than they ever had in her whole life: the ridging was gone and they were no longer splitting or bending. And her hair, which had begun to thin, was noticeably thicker again.
I know what you’re going to say: this is nothing but a testimonial, and she could have been mistaken: post hoc ergo propter hoc and all that. Hair salons are not reliable sources of health advice, and perhaps not even a very reliable source of hair advice. I am leery of their recommendations for expensive shampoos and gimmicky conditioners. They offer things I don’t want, like hair coloring (I consider my gray hairs hard-earned badges of honor), waxing, eyebrow arch threading, scalp massage, and facials. Some of them have tanning beds in a back room. Incredibly, several of them in my area even offer ear candling! (more…)
Last week I posted a list of 30 rebuttals to many of the recurrent criticisms that are made by people who don’t like what we say on SBM. I thought #30 deserved its own post; this is it. At the end, I’ve added a few items to the original list.
What’s the harm in people trying CAM? Science-based medicine has been criticized for being too rigid and intolerant. Why do we insist on randomized placebo-controlled trials to prove that a treatment is safe and effective? Isn’t it enough that patients tell us they feel better? Isn’t that what we all want, for our patients to feel better? Even if the treatment only works as a placebo, isn’t that a good thing? What’s the harm in that?
The albuterol/placebo study
I would argue that we don’t just want our patients to think they are better, we want them to actually be better. A study that illustrates that principle has been discussed on this blog before, here and here.
A group of patients using an effective albuterol asthma inhaler was compared to 2 placebo groups (a placebo inhaler group and a sham acupuncture group), and to a group that got no treatment at all. Patients reported the same relief of symptoms with each of the two placebo controls as with the albuterol inhaler; all three groups reported feeling significantly better than the no-treatment group. It could be argued that placebos are an effective treatment for the subjective symptoms of asthma. (more…)
Some people don’t like what we have to say on Science-Based Medicine. Some attack specific points while others attack our whole approach. Every mention of complementary and alternative medicine (CAM) elicits protests in the Comments section from “true believer” users and practitioners of CAM. Every mention of a treatment that has been disproven or has not been properly tested elicits testimonials from people who claim to have experienced miraculous benefits from that treatment. In previous articles I have compiled the criticisms of what I wrote about Protandim and Isagenix. It’s instructive to read through them. We welcome rational and substantive criticism, but most of these comments are neither.
Our critics keep bringing up the same old memes, and it occurred to me that rather than try to answer them each time, it might be useful to list those criticisms and answer them here. In future, when the same points are raised, we could save time and effort by linking to this page and citing the reference number. I know this list is not comprehensive, and I hope our readers will point out anything I’ve omitted. Here are some of the criticisms we keep hearing:
1. Big Pharma is paying you to promote their products and discredit CAM.
No it isn’t. We are not Pharma shills. We are not paid anything for writing this blog. We do not get money from pharmaceutical companies. We do not accept gifts from drug companies. We do not get kickbacks for prescribing certain drugs. We have no incentive to favor drugs over other treatments. Incidentally, critics who prefer natural remedies to pharmaceuticals should note that many CAM diet supplements are sold by subsidiaries of Big Pharma. (more…)
Until recently, the moment of birth was a surprise. We anxiously awaited the obstetrician’s announcement: “It’s a boy!” or “It’s a girl!” Then we checked to see if any crucial parts were missing and we counted the fingers and toes. We had to wait for a baby to be born before we could know its sex and whether it was normal. Today, thanks to prenatal testing, we can know the sex of a fetus, diagnose a number of genetic abnormalities and malformations, and we can even operate on the fetus in utero to correct certain problems before birth. I had amniocentesis for my two pregnancies because of the higher risk of Down syndrome at my age (37 and 39). It was reassuring to know the baby didn’t have Down syndrome, and it was fun for my husband to point to my burgeoning belly and introduce it to people as “our daughter Kristin.”
Amniocentesis is invasive, carries risks, and can’t be done until the 15th to 20th week of pregnancy. Now there is a safe, noninvasive, accurate blood test that can be done as early as the 9th week. It analyzes cell-free fetal DNA (cfDNA) circulating in the mother’s blood. It sounds ideal, but there are some caveats. It’s not yet appropriate to recommend it to all pregnant women. An editorial in The New England Journal of Medicine expressed concern that pressures are promoting diffusion of cfDNA testing beyond the boundaries of available evidence. (more…)
A Swedish researcher, Staffan Lindeberg, has been studying the inhabitants of Kitava, one of the Trobriand Islands of Papua New Guinea. He claims that sudden cardiac death, stroke, and exertion-related chest pain never occur in Kitava; and he attributes this to their eating a Paleolithic diet.
2,250 people live on Kitava. They are traditional farmers. Their dietary staples are tubers (yam, sweet potato and taro), fruit, fish, and coconut. They don’t use dairy products, alcohol, coffee, or tea. Their intake of oils, margarine, cereals, and sugar is negligible. Western foods constitute less than 1% of their diet. Their activity level is only slightly higher than in Western populations. 80% of them smoke daily and an unspecified number of them chew betel. The macronutrient composition of the Kitavan diet was estimated as 21% of total calories from fat, 17% from saturated fat, 10% from protein, and 69% from carbohydrates.
Lindeberg’s Kitava study examined a sample of 220 Kitavans aged 14-87 and compared them to healthy Swedish populations. They found substantially lower diastolic blood pressure, body mass index, and triceps skinfold thickness in the Kitavans. Systolic blood pressure was lower in Kitava than in Sweden for men over 20 and women over 60. Total cholesterol, LDL cholesterol, and apolipoprotein B were lower in men over 40 and in women over 60. Triglycerides were higher in Kitavans aged 20-39 than in Swedes of the same age. HDL was not significantly different. (more…)