Archive for the 'Science and Medicine' Category

Feb 21 2017

Potential New Pain Drug from Snail Venom

Cone-SnailResearchers have published in PNAS promising results from a snail venom analogue used in the treatment of pain. This is exciting for a number of reasons, even if the current compounds under study do not pan out.

Pain is a difficult clinical problem. There are limited options for treating chronic pain and we can quickly run out of options if patients cannot tolerate certain classes of drugs. What we really need are entirely new classes of pain medication, and that is what this new approach promises.

There are essentially two neurological components to pain: there is the physical sensation, and then there is the emotional component. It is interesting to ask the question, why does pain hurt? There is nothing about the sensation itself that is inherently painful. Any sensation is just nerve cells firing and carrying signals to areas of the brain that interpret those signals. Pain hurts because pain pathways specifically connect to the emotional centers in the brain to create a negative experience.

For further background, clinically it is helpful to distinguish different types of pain. There is nociceptive pain, which is the nervous system appropriately sensing damage and generating protective painful sensations. There is also neuropathic pain, which is the nervous system malfunctioning and producing inappropriate pain that is not protective. We further divide pain into acute and chronic. Finally, we consider the context of the patient, such as whether or not they are terminal.

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Feb 20 2017

Human Gene Editing

CRISPR-human editingThe recent rapid development of CRISPR technology, which has made gene editing fast, affordable, and accurate, has rekindled the ethical debate about human gene editing. Last week a special panel put together by the National Academy of Sciences gave a “yellow light” to human germline gene editing – saying that such editing might be ethical once the risks were properly assessed.

Germline editing means that the changes would be part of the gametes, the sperm or egg, and would therefore be passed down to offspring. If gene editing were done to a fertilized then this would affect all cells, including the germ cells.

By contrast somatic cell editing would affect only adult cells and not be passed down to the next generation. Such editing would only affect the individual.

The ethical controversy over germline editing is that such changes essentially can become a permanent part of the human population.

What Changes are Acceptable?

The NAS report essentially lays out two criteria for human germline editing. The first is that research shows that such editing is safe in humans without any unintended consequences. They want to make sure that dangerous changes to the human genome will not enter the human population. This is, of course, a perfectly reasonable criterion.

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Feb 17 2017

The Science of Smoking Bans

smoking-banIn a recent article for Slate, Jacob Grier argues that the science used to justify widespread bans on smoking in public places was flawed. Recent more robust research has show little to no health benefit from such laws, he argues. While he has a point regarding the arc of scientific evidence, I think he is going too far in the other direction in his conclusions about the science.

Second Hand Smoke

The current consensus of evidence is that there are health risks to second hand smoke, although they are statistically small. Debate centers around the magnitude of the effect, with few doubting that there is a negative health effect. Negative health effects include heart attacks, lung cancer, stroke, and exacerbation of asthma. On a population level, even small increased risks result in large numbers of excess deaths and negative health outcomes. The CDC estimates, for example, that second-hand smoke exposure results in 34,000 excess cardiac deaths each year.

Increased recognition of the health risks of passive smoke exposure lent significant political weight to anti-smoking efforts, resulting in a cultural shift over the last 30 years. As a result smoking has largely been banned in most indoor public places and many work places.

The empirical question on which Grier focuses is the impact of those smoking bans on health outcomes. He does a fairly thorough review of the literature, although I think his review is biased to make his point, that the health benefits of such bans have been overplayed and maybe don’t exist.

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Feb 16 2017

More Anti-Vaccine Nonsense from Trump and Kennedy

kennedy-deniroWe have an anti-vaccine president. One of my concerns about Trump the candidate was that one of his most consistent positions over the years was blaming vaccines for the alleged autism epidemic (there isn’t one, by the way). Once elected it did not take long for this to manifest as a policy priority. In January Trump met with RFK Jr. to discuss him heading an Orwellian commission on vaccine safety and scientific integrity.

At a recent meeting with educators, Trump continued to express his false belief in a “tremendous increase” in autism:

“Have you seen a big increase in the autism with the children?” Trump asked Jane Quenneville, the principle of a Virginia public school that specializes in special education. Quenneville responded that she had.

Trump continued: “So what’s going on with autism? When you look at the tremendous increase, it’s really such an incredible — it’s really a horrible thing to watch, the tremendous amount of increase. Do you have any idea?”

“The autism?” Really? Continue Reading »

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Feb 03 2017

Pew Vaccine Survey – Some Good and Bad News

Pew recently published a surveyvaccines-Pew-2017 looking at the attitudes of Americans regarding the safety and effectiveness of vaccines. The results are not surprising, but there are some interesting bits in the data.

The headline main results are that 88% of those surveyed thought that the benefits of vaccines outweigh the risks, while only 10% thought the risks outweigh the benefits. Further, 82% supported mandatory vaccinations for healthy school children.

This is both good and bad news. It means a solid majority of Americans understand that vaccines are safe and effective. However, the minority who doubt the safety of vaccines are enough to cause problems. Also, those numbers are a bit worse when you dig into the data.

Parents of young children, age 0-4, were more negative about vaccines, with only 81% stating that the benefits outweigh the risks, compared to 91% of those with older children and 90% of those with no children.  Parents of young children are the ones deciding if they get vaccinated. The reason for this is likely that parents with young children are facing the decision of whether or not to vaccinate and are looking for information online. They are therefore more likely to come across anti-vaccine propaganda. Parents of young children may also be easier to scare than more experienced parents.

These numbers are important because of herd immunity – if enough of the population is vaccinated, then a disease outbreak cannot find enough susceptible hosts to spread and will therefore peter out quickly. This will keep the disease from being endemic, meaning that it is self-sustaining in the population. Continue Reading »

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Jan 23 2017

Acupuncture for Infantile Colic

crying+babyRecently scientists published initial results from an ambitious project to reproduce the results of 50 influential cancer studies. The first five studies resulted in one clear failure to replicate, two partial replications, and two with uninterpretable results.

This is how science works. No one study is definitive, because there are simply too many ways to generate spurious results (even without fraud and with the best intentions). Replication is the final arbiter – any result that is real should consistently reproduce. Results that are spurious will be inconsistent.

These are the core lessons that I have been repeating here and on SBM – most studies are flawed and their results are unreliable. Most false studies are false positive. Even experienced and well-meaning researchers can fall victim to p-hacking and other subtle errors. You can only arrive at a reliable conclusion by looking at a mature and robust research program involving numerous studies and replications. The various replication projects that are under way are confirming this overall impression.

Let’s turn to one of my favorite examples: acupuncture. Acupuncture involved sticking thin needles into specific areas of the body in order to provoke specific clinical benefit, such as pain reduction. There have been several thousand studies of acupuncture. When you review all the research you find, put simply, that acupuncture does not work, for anything. There is no specific effect here, one that is reliably found when appropriately controlled for. The entirety of the research is highly consistent with the conclusion that acupuncture is nothing more than a theatrical placebo.

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Jan 12 2017

Curcumin Hype vs Reality

CurcuminCapsA recent systematic review of the alleged health benefits of curcumin show that, yet again, hype based on “traditional use” is not a reliable guide.

Curcumin is a spice that makes up about 5% of turmeric, a yellow spice used in many curries. It is also a traditional herbal treatment. The health claims made for curcumin are numerous – WebMD has this entry:

Other preliminary lab studies suggest that curcumin or turmeric might protect against types of skin diseases, Alzheimer’s disease, colitis, stomach ulcers, and high cholesterol. Based on lab studies, turmeric and curcumin might also help treat upset stomach, scabies, diabetes, HIV, uveitis, and viral infections.

The systematic review had two main findings:

No double-blinded, placebo controlled clinical trial of curcumin has been successful. This manuscript reviews the essential medicinal chemistry of curcumin and provides evidence that curcumin is an unstable, reactive, nonbioavailable compound and, therefore, a highly improbable lead.

Let’s take the second point first, bioavailability. In order for a drug to be useful when taken orally it has to have adequate bioavailability. This means it needs to be relatively stable, it has to be absorbed in adequate amounts through the GI tract, and then it has to survive a first pass through the liver and be distributed in the body in such a way that it gets to its target tissue is sufficient concentration to have a clinical effect.

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Jan 10 2017

Cleveland.com Doubles Down on Fail

vaccine-shot-promoThere are several phases to a serious gaffe. First, there are the conditions which led to or allowed the gaffe to occur. Then there is the gaffe itself. There is then the response of the person or institution who committed the gaffe – which is perhaps the most important phase . Finally, there may or may not be a long term correction of the underlying conditions.

Over the weekend, as I discussed yesterday, Dr. Daniel Neides, Medical Director and Chief Operating Officer of the Cleveland Clinic Wellness Institute, published an anti-vaccine screed on cleveland.com. I won’t bother debunking the anti-vaccine pseudoscience again, just read my post from yesterday. You can also read David Gorski’s excellent take down at Science-Based Medicine.

Suffice it to say the column was full of misinformation and common anti-vaccine tropes that are long debunked. The publication of a dangerous anti-science rant by Cleveland Clinic’s Director of the Wellness Center was, of course, the gaffe.

The conditions that led to that gaffe are obvious, and something about which my SBM colleagues and I have complained for years- the infiltration of alternative medicine pseudoscience into academic medical institutions. Cleveland Clinic has an “integrative medicine” center headed by Mark Hyman, who co-authored an anti-vaccine book. The Wellness Center itself embraces all sorts of vitalistic nonsense and pseudoscience.

As David says – no one should be surprised when the director of a center that embraces quackery publishes an article that embraces quackery. Continue Reading »

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Jan 09 2017

Anti-vaccine Nonsense at Cleveland Clinic

This is what happens when you compromise your academic and professional integrity in order to embrace a popular fad. The Cleveland Clinic, which is historically an excellent medical institution, has the Cleveland Clinic Wellness Center, which is a center of so-called “alternative” medicine.

Such centers are a Trojan horse. They are sold to naïve academics as providing “patient centered” warm and fuzzy symptomatic treatments. Meanwhile they are really centers for pseudoscience and health fraud. They use the respected names of venerable institutions to legitimize nonsense.

The Cleveland Clinic now has to face the PR nightmare of allowing the foxes into the henhouse (actually they built a new henhouse just for the foxes).

On January 6th Dr. Daniel Neides, Medical Director and Chief Operating Officer of the Cleveland Clinic Wellness Institute, published an anti-vaccine screed on the institution’s blog. The article is full of typical anti-vaccine misinformation, and is a serious embarrassment to the Cleveland Clinic. It will also embolden the anti-vaccine movement, who can point to the article to make vaccines seem controversial and convince more confused parents not to vaccinate their children.

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Jan 06 2017

Another Child Dies of Medical Neglect

seth-johnsonLast year 7-year-old Seth Johnson died of pancreatitis. His parents, Timothy and Sarah, are now on trial for one count of child neglect.

These are always heartbreaking stories, especially for a parent. Strong and conflicting emotions are stirred – on the one hand I feel anger and resentment toward the parents, who allowed their child to needlessly suffer and die. At the same time I also feel sorry for the parents. There is nothing worse than the death of a child, except feeling responsible for that death yourself. The state can add little to the emotional punishment they must be  already experiencing (although they should try damn hard).

Seeing such parents as victims is not a popular position. It is much easier to see them as villains, even demons. I always strive to see reality in all its complexity, and as a result I often conclude that such parents are some combination of villain and victim. My thoughts also come with the huge caveat that I am getting all my information from the media, and do not have direct access to the medical information or the parent’s story.

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