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Confusing overdiagnosis for an “epidemic” of thyroid cancer in Japan after Fukushima

A Japanese girl being screen for thyroid cancer.

A Japanese girl being screen for thyroid cancer.

One of my favorite topics to blog about for SBM is the topic of overdiagnosis and overtreatment. These are two interrelated phenomena that most people are blissfully unaware of. Unfortunately, I’d also say that the majority of physicians are only marginally more aware than the public about these confounders of screening programs, if even that.

Overdiagnosis has long been appreciated to be a major impediment to translating programs to screen for disease into better outcomes in a number of diseases but has only recently really seeped into the public consciousness, beginning in particular in 2009 when the United States Preventative Services Task Force (USPSTF) issued mammography recommendations that pushed back the recommended age to start screening to 50. Certainly, the concept of overdiagnosis is counterintuitive. After all, why do we screen for disease in asymptomatic people? The reason is simple—and maddeningly intuitive. We screen for disease based on the belief that catching potentially deadly diseases like cancer early, before they produce clinical symptoms, will allow earlier intervention and save lives. It seems blindingly obvious that this should be the case, doesn’t it? Unfortunately, real life biology and pathophysiology aren’t quite so neat and tidy, and the relationship between early detection and improved survival is muddied by phenomena such as lead time bias and the Will Rogers effect, in addition to overdiagnosis.

What is overdiagnosis? In brief, it is the detection of pathology or disease that, if left untreated, would never endanger the life of a patient or even harm him. Note that overdiagnosis is not the same thing as a false positive. A false positive occurs when a test detects disease that isn’t really there; in contrast with overdiagnosis there is definite pathology. The disease being screened for is there, at least in an early form. It’s just that, at the very early stage detected, it’s either not progressive or so indolent that the patient will grow old and die of something else before it would ever cause a problem. Indeed, it’s been estimated that as many as one in three breast cancers detected by mammography in asymptomatic women might be overdiagnosed and that one in five might spontaneously regress. However, because we don’t know which ones are unlikely to cause harm and haven’t worked out a safe method of observing them and intervening if they look as though they are progressing, we are obligated to treat them all when discovered. The problem of overdiagnosis has led to multiple alterations in what once were considered definitive recommendations for screening mammography, first by the USPSTF and most recently by the American Cancer Society.
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Posted in: Cancer, Epidemiology

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Ezekiel Stephan: Another Pediatric Death by World View

Ezekiel
Reports of a disturbing chain of events that ended in the likely preventable death of a 19-month-old Canadian child have made the rounds this week. The case was discussed by friend of Science-Based Medicine Orac (who I believe is some kind of a protocol droid) on Respectful Insolence two days ago. But even if you’ve read that excellent post, please continue reading as I have updated information and, I believe, additional insight into this unfortunate outcome.

If this is your first encounter with the story, prepare to be angry and frustrated but don’t presume to know everything that happened. The numerous news reports, beginning back in 2013 when the parents were first charged and the case went public, are not all well-written and there are discrepancies between accounts. Add to that the announcements and fundraising efforts by the family on Facebook and various other crowdfunding websites, and their alleged side of the story as reported by disreputable sources steeped in pro-woo/anti-vaccine bias, and we have one confusing mess of facts and a heap of conspiracy claims to boot. The only aspect of this case that is completely irrefutable is that a child suffered and died, and that he was failed by people who should have known better. (more…)

Posted in: Science and Medicine

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Not natural, not safe: Grapefruit Seed Extract

The image is "natural", but is grapefruit seed extract a case of misleading advertising?

The image is “natural”, but is grapefruit seed extract a case of misleading advertising?

Where do you draw the line between “supplement” and “drug”? And how much processing of a “natural” substance can occur before it’s no longer “natural”? These seemingly-philosophical questions are very real when it comes to the supplement industry. In many countries, regulators have implemented weaker safety, effectiveness and quality standards for anything branded a supplement or natural health product. The result has been a boon and boom for manufacturers, with thousands of products flooding the market. This same boom has challenged consumers and health professionals who are seeking products that are safe, effective, and manufactured to high quality standards (and in the bottle you are buying). Nowhere is this challenge better illustrated than a supplement that I’ve seen for sale for some time. Grapefruit seed extract (GSE), according to promoters, is a panacea that destroy bacteria, viruses and fungi anywhere in the body, without any risk of harm. But the actual science is quite telling. Grapefruit seed is a supplement that’s of such poor quality that even herbal medicine boosters recommend against its use. (more…)

Posted in: Herbs & Supplements

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P Value Under Fire

coinflipThe greatest strength of science is that it is self-critical. Scientists are not only critical of specific claims and the evidence for those claims, but they are critical of the process of science itself. That criticism is constructive – it is designed to make the process better, more efficient, and more reliable.

One aspect of the process of science that has received intense criticism in the last few years is an over-reliance on P-values, a specific statistical method for analyzing data. This may seem like a wonky technical point, but it actually cuts to the heart of science-based medicine. In a way the P-value is the focal point of much of what we advocate for at SBM.

Recently the American Statistical Association (ASA) put out a position paper in which they specifically warn against misuse of the P-value. This is the first time in their 177 years of existence they have felt the need to put out such a position paper. The reason for this unprecedented act was their feeling that abuse of the P-value is taking the practice of science off course, and a much needed course correction is overdue. (more…)

Posted in: Science and Medicine

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Statin Side Effects

statins

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.
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Posted in: Pharmaceuticals

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The claim that Gardasil causes premature ovarian failure: Ideology, not science

It's amazing how, to antivaccine activists, it just so happens that a vaccine that targets a sexually transmitted virus must also destroy a girl's ovaries.

It’s amazing how, to antivaccine activists, it just so happens that a vaccine that targets a sexually transmitted virus must also destroy a girl’s ovaries. It must be a coincidence, right?

When you’ve been blogging for over 11 years on your own blog and 8 years on a blog like Science-Based Medicine, particularly when what you blog about is skepticism and science-based medicine, with a special emphasis on rationally and scientifically discussing quackery, inevitably you see the same misinformation and lies pop up again and again. Indeed, those of us in the biz not infrequently refer to such stories as “zombie lies,” because no matter how often you think they’ve been killed they always come back. Personally, I like to refer to them as Jason, Michael Myers, or Freddy Krueger lies (or just slasher or monster lies), for basically the same reason. You kill them with facts, evidence, science, and reason, but sooner or later they always come back. Always. That’s why trying to refute them is like playing Whac-A-Mole. This time around, a group called the American College of Pediatrics (ACP) is claiming that Gardasil is causing infertility in girls, a claim that showed up last week on that repository of quackery, NaturalNews.com. Oddly enough, despite the article’s hysterical tone, it wasn’t written by NN’s big macher himself, Mike Adams.

The reason that slasher lies keep coming back is because they never really go away completely. They only look that way because they recede for a while until someone new discovers them or their originators decide the coast is clear and they can repeat them again. There’s one particular slasher lie that keeps coming up about the HPV vaccine, usually Gardasil (mainly because that’s the brand of HPV vaccine most commonly used in the US) but not restricted to Gardasil. Sometimes Cervarix falls prey to the same lies, mainly overseas where it is the predominant version of HPV vaccine used. Given that I was in Boston at the annual meeting of the Society of Surgical Oncology over the weekend and was also busy hanging out with Kimball Atwood and Clay Jones one night, surgical colleagues another night, and the Boston Skeptics on Saturday, it seemed to me to be a good time to revisit this topic, particularly given that it hasn’t been covered on SBM before. If this post looks familiar, it’s because it has appeared before, but it was in a different form. Consider this a beefed up version of the prior post, because even when I recycle material I can’t just recycle it unchanged. I have to tinker, add, and, of course, customize for the blog. It’s what I do.
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Posted in: Public Health, Religion, Vaccines

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Acupuncture for Coronary Artery Disease

Pictured: Really, really bad idea, on all levels.

Pictured: Really, really bad idea, on all levels; literal, metaphorical, pedagogical, tautological, hemodynamic, pathological, basically all the -ics, -cals, and -als.

I have spent the last 35 years mostly in acute care medicine. Spending my day in the hospital gives me the bias that we are fragile creatures who can die unexpectedly and easily. Much of the time we pull patients through, but I have a great respect for acute diseases. Over the years I have seen too many people wake up feeling good and dead by dinner time

There is a reason the phrase is “as serious as a heart attack”. Heart attacks and heart arrhythmias can kill. About 5% of patients admitted to the hospital with a heart attack die. And 250,000 have sudden death each year, never making it to the hospital, succumbing to their ventricular fibrillation precipitated by acute coronary ischemia. Ted Cruz notwithstanding, you need a functioning heart to live.

Scary stuff. So when I read Pubmed articles like “Effects of Acupuncture at the Yintang and the Chengjiang Acupoints on Cardiac Arrhythmias and Neurocardiogenic Syncope in Emergency First Aid“, I wonder what is going on in the minds of some people. (more…)

Posted in: Acupuncture, Clinical Trials

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Patient Beware: Off-label drug promotion by pharmaceutical companies

In truth, physicians are rarely this happy to see a drug rep.

In truth, physicians are rarely this happy to see a drug rep.

Pharmaceutical companies and their sales reps can distribute information, such as medical journal articles, about unapproved (“off-label“) uses of their drugs as long as they adhere to FDA guidelines. However, the FDA takes the position that this information must be distributed separately from information that is “promotional in nature,” i.e., for marketing purposes, a position that is now open to question.

Off-label promotion of a drug for a use that has not been approved by the FDA is, in the FDA’s view, a violation of the federal Food, Drug & Cosmetic Act (FDC Act). It is subject to criminal prosecution, because promoting a drug for new, unapproved uses is evidence of an intent that the drug be used before it has gone through the extensive process of clinical trials and a review of the evidence of safety and efficacy by a panel of experts, as required by law before a drug can be marketed. Thus, off-label promotion is seen as an end-run around the approval process that perverts the purpose of the FDC Act, which is to protect the public from ineffective and unsafe drugs.

Studies show that personal sales visits to physicians by pharmaceutical reps (called “detailing”) drives prescriptions in favor of the drugs being promoted. This is true even though physicians’ view of detailing ranges from neutral to highly negative, a “necessary evil,” and physicians are aware of potential conflicts of interest these visits precipitate.

While there are restrictions on off-label promotion, off-label prescribing by a physician is not illegal. Physician practice is regulated by the states and not within the jurisdiction of the FDA. In fact, off-label prescribing is considered both ethical and within the standard of care in appropriate circumstances. (I am currently taking a drug for an off-label use, and was informed of this, plus the risks and benefits, by my physician prior to his prescribing it.) It is also common, according to an article by law professors Ryan Abbot and Ian Ayers in the Duke Law Journal, which is well worth reading:

for the 3 leading drugs in each of the 15 leading drug classes, off-label use accounts for approximately 21% of prescriptions. Moreover, off-label uses may be the norm in some areas of practice, such as oncology, pain management, and palliative care, and in some patient populations, such as children, the elderly, and the severely ill. For example, about 80 percent of all drug prescriptions for children are off-label, and between 80 and 90 percent of all drug prescriptions for rare diseases are off-label. [Footnotes omitted.]

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Posted in: Clinical Trials, Ethics, Legal, Pharmaceuticals, Politics and Regulation

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Bad Reporting about Uploading Memories

hemisity
The Mirror declares, ‘Scientists develop Matrix-style technique of ‘feeding’ information directly into your brain.’ Discovery News went with, “Novices ‘Download’ Pilots’ Brainwaves, Learn To Fly.” Most other outlets spoke of ‘uploading’ information to the brain, and learning in seconds.

The one thing I was certain of from reading these headlines is that this was not what was happening. Brain-machine interface technology is progressing rapidly, but we are a long way away from downloading information from or uploading information to the human brain.

The news outlets reported that electrical activity was recorded from pilots and then used to stimulate the subject. They also reported that this enhanced learning by 33%.

What actually happened

Here is the actual study: “Transcranial Direct Current Stimulation Modulates Neuronal Activity and Learning in Pilot Training.”

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Posted in: Neuroscience/Mental Health

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The Essential Role of Regulation In Human Health and In Ecology: The Serengeti Rules

serengeti

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…)

Posted in: Basic Science, Book & movie reviews, Cancer

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