Category: doctor logic

Saturated Fat and Heart Attacks

Seth Roberts26 Comments

After I discovered that butter made me faster at arithmetic, I started eating half a stick (66 g) of butter per day. After a talk about it, a cardiologist in the audience said I was killing myself. I said that the evidence that butter improved my brain function was much clearer than the evidence that butter causes heart disease. The cardiologist couldn’t debate this; he seemed to have no idea of the evidence.

Shortly before I discovered the butter/arithmetic connection, I had a heart scan (a tomographic x-ray) from which is computed an Agaston score, a measure of calcification of your blood vessels. The Agaston score is a good predictor of whether you will have a heart attack. The higher your score, the greater the probability. My score put me close to the median for my age. A year later — after eating lots of butter every day during that year — I got a second scan. Most people get about 25% worse each year. My second scan showed regression (= improvement). It was 40% better (less) than expected (a 25% increase). A big increase in butter consumption was the only aspect of my diet that I consciously changed between Scan 1 and Scan 2.

The improvement I observed, however surprising, was consistent with a 2004 study that measured narrowing of the arteries as a function of diet. About 200 women were studied for three years. There were three main findings. 1. The more saturated fat, the less narrowing. Women in the highest quartile of saturated fat intake didn’t have, on average, any narrowing. 2. The more polyunsaturated fat, the more narrowing. 3. The more carbohydrate, the more narrowing. Of all the nutrients examined, only saturated fat clearly reduced narrowing. Exactly the opposite of what we’ve been told.

As this article explains, the original idea that fat causes heart disease came from Ancel Keys, who omitted most of the available data from his data set. When all the data were considered, there was no connection between fat intake and heart disease. There has never been convincing evidence that saturated fat causes heart disease, but somehow this hasn’t stopped the vast majority of doctors and nutrition experts from repeating what they’ve been told.

Assorted Links

Seth Roberts6 Comments

Thanks to Alex Chernavsky.

Progress in Psychiatry and Psychotherapy: The Half-Full Glass

Seth Roberts3 Comments

Here is an excellent introduction to cognitive-behavioral therapy (CBT) for depression, centering on a Stanford psychiatrist named David Burns. I was especially interested in this:

[Burns] currently draws from at least 15 schools of therapy, calling his methodology TEAM—for testing, empathy, agenda setting and methods. . . . Testing means requiring that patients complete a short mood survey before and after each therapy session. In Chicago, Burns asks how many of the therapists [in the audience] do this. Only three [out of 100] raise their hands. Then how can they know if their patients are making progress? Burns asks. How would they feel if their own doctors didn’t take their blood pressure during each check-up?

Burns says that in the 1970s at Penn [where he learned about CBT], “They didn’t measure because there was no expectation that there would be a significant change in a single session or even over a course of months.” Forty years later, it’s shocking that so little attention is paid to measuring whether therapy makes a difference. . . ”Therapists falsely believe that their impression or gut instinct about what the patient is feeling is accurate,” says May [a Stanford-educated Bay Area psychiatrist], when in fact their accuracy is very low.

When I was a graduate student, I started measuring my acne. One day I told my dermatologist what I’d found. “Why did you do that?” he asked. He really didn’t know. Many years later, an influential psychiatrist — Burns, whose Feeling Good book, a popularization of CBT, has sold millions of copies — tells therapists to give patients a mood survey. That’s progress.

But it is also a testament to the backward thinking of doctors and therapists that Burns didn’t tell his audience:

–have patients fill out a mood survey every day
–graph the results

Even more advanced:

–use the mood scores to measure the effects of different treatments

Three cheap safe things. It is obvious they would help patients. Apparently Burns doesn’t do these things with his own patients, even though his own therapy (TEAM) stresses “testing” and “methods”. It’s 2013. Not only do psychiatrists and therapists not do these things, they don’t even think of doing them. I seem to be the first to suggest them.

Thanks to Alex Chernavsky.

Eric Kandel Sheds Light On Who Wins Nobel Prizes

Seth Roberts8 Comments

The most interesting thing about the Nobel Prize in Medicine is its predictable irrelevance to major health problems. Year after year, the prize-winning work has failed to reduce heart disease, cancer, depression, stroke, diabetes, schizophrenia, and so on. Another interesting thing about the Nobel Prize in Medicine is that Eric Kandel, a Columbia Medical School professor, managed to win one. In 1986, a book called Explorers of the Black Box: The Search for the Cellular Basis of Memory by Susan Allport told how Kandel tried to take credit for other people’s discoveries. Not a pretty picture. Yet in 2000 he won a Nobel Prize for those or very similar discoveries. Did Allport exaggerate? Did her sources deceive her? Did Kandel — contrary to what Allport’s book seems to say — deserve a Nobel Prize?

I can’t answer these questions. However, a recent article by Kandel (“A New Science of Mind”) in the New York Times sheds light on how well he understands medicine and neuroscience. Not well, it turns out. He writes:

We are nowhere near understanding [psychiatric disorders] as well as we understand disorders of the liver or the heart.

Actually, our understanding of liver and heart disorders is close to zero, matching our understanding of psychiatric disorders. If we had some understanding of heart disease, for example, we would know why heart disease is much rarer in Japan than in the United States. Read more “Eric Kandel Sheds Light On Who Wins Nobel Prizes”

“The Cause of Ulcers is Bacteria” Makes as Much Sense as “The Cause of Car Accidents is Cars”

Seth Roberts10 Comments

If I were to look at you, and say, in a serious tone of voice, “The cause of car accidents is cars”, you’d think I’m nuts. It’s not a useful statement. Yet many medical and science experts — including the people who award the Nobel Prize in Physiology or Medicine — believe it is helpful to say “the cause of ulcers is bacteria”. The two statements are similar because only a small percentage of cars get in accidents and only a small percentage of people infected with H. pylori, the bacterium that supposedly “causes ulcers”, get ulcers. A helpful investigation of what causes ulcers would figure out the crucial difference(s) between those infected with H. pylori who don’t get ulcers (almost all) and those who do (very few).

I recently encountered the “the cause of ulcers is bacteria” twice in one day. Once in a book review by John Timpane:

Barry Marshall, who discovered what causes stomach ulcers, played fast, loose, and messy with his methods and data. He was right, and got the right answer, and now we know.

(Timpane is right about the “fast, loose, and messy” part. Marshall ingested a large number of H. pylori. He failed get an ulcer — and claimed the outcome supported his view that H. pylori causes ulcers.) And once in The New Yorker, in a long article about the benefits of microbes, especially H. pylori, by Michael Specter:

In 1982, to the astonishment of the medical world, two scientists, Barry Marshall and J. Robin Warren, discovered that H. pylori is the principal cause of gastritis and peptic ulcers.

Should I expect science journalists to understand causality? Maybe not. But it is interesting that the people who award the Nobel Prize in Medicine and “the medical world” do not understand it.

How to Detect Dementia

Seth Roberts7 Comments

Dementia is common. You might think that doctors and neuropsychologists would have a good understanding of how to detect it. Judging from a recent New York Times article, they don’t. The article is based on a study that found that people who report memory problems not detected by a standard test turn out to be more likely to end up with dementia (measured by a standard test) than those that don’t. This isn’t surprising; what’s more revealing is how people who report memory problems have been treated in the past: their complaints have been dismissed. For example:

Patients like this have long been called “the worried well,” said Creighton Phelps, acting chief of the dementias of aging branch of the National Institute on Aging. “People would complain, and we didn’t really think it was very valid to take that into account.”

Doctors had no idea whether these complaints were valid but rather than admit this ignorance they . . . confabulated. They claimed, based on nothing, that the complaints were not valid. It reminds me of a surgeon telling me that research supported her claim that I needed surgery (for a hard-to-notice hernia). No such research existed. When I asked her what research? she said she would find it. She was bluffing, in other words. That’s just one doctor making up evidence. Here it has been a whole group of doctors.

The problem isn’t just confabulation. Apparently doctors in this area fail to understand basic principles of measurement. When Patient Y visits Doctor X and complains of memory problems, Doctor X gives Patient Y a series of memory tests. Only if Patient Y scores below normal range does Doctor X think that Patient Y’s complaint is “real”. For example:

The man complained of memory problems but seemed perfectly normal. No specialist he visited detected any decline. “He insisted that things were changing, but he aced all of our tests,” said Rebecca Amariglio, a neuropsychologist at Brigham and Women’s Hospital in Boston.

Amariglio apparently fails to understand that a series of measurements on one person — which is what the man’s complaint was based on, comparing himself now to himself in the past — is going to be vastly more sensitive to change than a comparison of one person to other people. A reasonable response to a complaint of memory loss would be: This is hard to detect with a one visit. Let’s give you a sensitive test and have you come back in six months to see if you decline more than normal. Judging from the Times article, doctors still haven’t figured this out.

Speaking of memory decline, Posit Science still hasn’t sent me the data they promised to send me.

Thanks to Alex Chernavsky.

The Rise and Fall of Heart Disease

Seth Roberts11 Comments

Heart disease was once the number one killer in rich countries. Maybe it still is. Huge amounts of time and money have gone into trying to reduce it — statins, risk factor measurement (e.g., cholesterol measurement), telling people to “eat healthy” and exercise more, and so on. Unfortunately for the poor souls who follow the advice (e.g., take statins), the advice givers, such as doctors, never make clear how little they know about what causes heart disease. Maybe they don’t realize how little they know.

I encountered an ignorant-without-knowing-it expert after a talk I gave about the effect of butter on brain function. I found that butter improved my brain function (measured by arithmetic speed). I had been eating lots of butter for more than a year. A cardiologist in the audience said I was killing myself. He thought butter caused heart disease. I said that I had experimental data that butter was good for me. Easy to interpret. The notion that butter is bad has come from epidemiological (non-experimental) data, which is hard to interpret. The cardiologist said that the epidemiology has not been misleading. One sign of our correct understanding, he said, is that heart disease has declined. I said there were many possible reasons for the decline.

A 2012 paper called “An epidemic of coronary heart disease” by David Grimes, a British doctor, could hardly make clearer how little we know about the cause of heart disease. Grimes points out that before 1920 heart disease was almost non-existent, that it rose sharply from 1930 to 1970 and since 1970 has declined sharply, at roughly the same rate that it rose. Both the rise and the fall are mysteries, says Grimes, in agreement with what I told the cardiologist. The rise and fall contradict all popular explanations. Heart disease cannot be due to obesity or wealth — both increased substantially at the same time heart disease fell sharply. Nor was the decline due to government intervention:

The decline of CHD deaths in the UK was further described in a UK Government report of 2004, Winning the War on Heart Disease. In this report, the government predictably but undeservedly assumed responsibility for the decline. Clearly, the NHS [National Health Service] in the UK could not have had an international effect [the decline is international].

“There [has been] no obvious effect of statin therapy or other medical intervention,” Grimes continues. Yet statins continue to be prescribed in very high amounts and very great expense. The NNT (number of people you need to treat to save one life) is often in the thousands, he noted.

Those who complain about the high cost of health care fatally fail to grasp this enormous ignorance — about many things, not just heart disease — and its consequences. Reducing the cost of health care (reducing the cost of statins, for example) would improve health if cost were the only thing deeply wrong with our health care system. It isn’t.

Hospitals and Their Employees: Stuck in the 1800s

Seth Roberts3 Comments

An article in the New York Times describes how difficult it has been for hospital administrators to get their employees to wash their hands. Hospital-acquired infections are an enormous problem and cause many deaths, yet “studies [in the last 10 years] have shown that without encouragement, hospital workers wash their hands as little as 30 percent of the time that they interact with patients.” Hospitals are now — just now — trying all sorts of things to increase the hand-washing rate. The germ theory of disease dates from the 1800s. Ignasz Semmelweis did his pioneering work, showing that hand-washing dramatically reduced death rate (from 18% to 2%), in 1847.

So hospitals are only now (in the last few years) grasping the implications of facts and a well-established theory from the 1800s. What goes unsaid in the usual discussion of how awful this is — how dare doctors refuse to wash their hands!, a sentiment with which I agree — is how backward both sides of the discussion are. A discussion in which many lives are at stake.

The Times article now has 209 comments, many by doctors and nurses. The doctors, of course, went to medical school and passed a rigorous test about medicine (“board-certified”). Yet they don’t know basic things about infection. (One doctor, in the comments, calls hand-washing “ this current fad“.) They appear to have no idea that it is possible to improve the body’s ability to resist infection. I read all the comments. Not one mentioned two easy cheap low-tech ways to reduce hospital infections:

1. Allow patients to sleep well. The body fights off infection during sleep, but hospitals are notoriously bad places to sleep. Patients are woken up by nurses, for example. You might think that everyone knows sleep helps fight infection . . . but apparently not hospital administrators nor the doctors and nurses who commented on the Times article. It was in the interest of these doctors and nurses to suggest alternative solutions because they dislike washing their hands.

2. Feed patients fermented foods (or probiotics). Fermented foods help you fight off infections. I believe this is because the bacteria on fermented food are perfectly safe yet successfully compete with dangerous bacteria. In any case, plenty of studies show that probiotics and fermented foods reduce hospital infections. In one study, “use of probiotics reduced the new cases of C. difficile-associated diarrhea by two thirds (66 per cent), with no serious adverse events attributable to probiotics.” Maybe this just-published article (Probiotics: a new frontier for infection control”) will bring a few people who work in hospitals into the 21st century.

That hospital administrators and their doctors and nurses — and, in this discussion, their critics — are stuck in the 1800s is clear enough. What is slightly less clear is that our understanding is better now than it was in the 1800s and some of the new knowledge is useful.

Thanks to Bryan Castañeda.

Oral Rehydration Therapy For Diarrhea

Seth Roberts9 Comments

Oral rehydration therapy (ORT) is given to people (usually children) suffering from diarrhea, which before ORT was often fatal. It is very simple: The sufferer drinks water with sugar and salt ad libitum (as much as they want). You probably haven’t heard of ORT — at least, I hadn’t. Everyone has heard of antibiotics. Yet “ in 10 years [ORT] saved more lives than penicillin had in 40.” Infant diarrhea was once (and may still be) the main cause of death in poor countries.

A history of its discovery supports several things I’ve said on this blog. One is Thorstein Veblen’s point about the disdain among professional scientists for useful research:

ORT might also have been developed long before 1968 but for the attitudes of the dominant medical establishment toward practical experimentation, which the Cholera Research Laboratory and the National Institutes for Health shared. Nalin believes that “the people at the lab … got kudos for the extent to which [their] work was not practical. As soon as it became practical it was discarded like a soiled towel–it was too common, too hands-on… so the prestige went to people who measured trans-intestinal fluxes or electrical currents”.

No one who has attended an elite law school, medical school, or graduate program in education will be surprised by this.

Another is the great resistance among the medical establishment to cheap and effective solutions:

The formidable and persistent ignorance of the Western medical establishment, which continues over twenty-five years after the discovery of ORT, is phenomenal. While its refusal to advocate ORT may be due in part to the notion that ORT is only necessary for people in the developing world, its actions appear to be driven also by financial considerations. Most hospitals do not train physicians in the use of ORT since they have no financial reason to do so. [I think “since” overstates what is known — Seth] The use of intravenous therapy, which often involves keeping a dehydrated child overnight, assures [greater] insurance reimbursement. Sending children home with ORT would [reduce] profits. Furthermore, recent studies show that diarrhoeal illness among the elderly may incur even greater health care costs that could also be reduced by the use of ORT. At a time of heated discussion about cost-containment in health care, it seems all the more ironic and egregious that a superior, cheap, and proven therapy [fails to replace] a far more expensive one. Estimates based on the cost of hospitalizations and physician visits suggest that ORT could save billions of dollars annually.

As an example of the resistance of American doctors to a better therapy, an ORT researcher, who had used it on Apache reservations in America, told this story:

I had an anthropologist friend who adopted an Apache child from the [Arizona] reservation where we were working. He used to be the anthropologist on the reservation. And then he [left the reservation and] went to Arkansas to teach and the Apache child came down with severe diarrhea and he called me up and he said desperately, “Look, my son’s in the hospital and they’re giving him all sorts of intravenous fluids. The diarrhea’s not stopping, he’s losing weight, they’re not feeding him. I know that you did this work in Arizona [on the reservation] and it didn’t look like that. . . . Would you call this professor of pediatrics and just collegiately talk to him?” So I called up the professor and told him that in our experience with Apache children this is what we found and here’s the publication and so on. And he said to me, “Doctor, doctor, our [Arkansas] children are not the same as your [reservation] children”. He was treating an Apache child from the same reservation.

Shades of Downton Abbey (where Lady Sybil died because a London doctor was listened to instead of a rural doctor).

End-of-Life Medicine: Enormous Lack of Informed Consent

Seth Roberts16 Comments

A few weeks ago I blogged about undisclosed risks of medical treatments. Undisclosed risks are common. They might be the norm. The situation would be even worse — in some sense, much worse — if doctors knew of these risks and failed to tell their patients. It was unclear if doctors knew of the undisclosed risks I wrote about.

Recently Tyler Cowen quoted a newspaper story about Israeli doctors giving birth control injections to Ethiopian women immigrants ”without their knowledge or consent.” Every commenter thought this was repugnant.

The latest RadioLab podcast (“The Bitter End”) is about the dramatic difference between how doctors want to be treated when they are near death (they want no CPR, no ventilator, no dialysis, no surgery, no chemotherapy, no feeding tube, no antibiotics, nothing except pain medicine) and how the general public wants to be treated (most people want CPR, ventilator, dialysis, surgery, chemotherapy, feeding tube, antibiotics, and so on).

The RadioLab guys were puzzled by the difference. Upon investigation, they learned that the big differences exist because all those medical procedures (except pain medicine) have much worse outcomes than the public is told. The doctors know about the bad outcomes. It is better to die, the doctors decide. Unless doctors have less tolerance for being in a vegetative state, having ribs broken, and so on than the rest of us, it is clear that most people agree to these procedures because of ignorance. They fail to know what actually happens because the people who know — doctors — fail to tell them.

In other words, a huge number of sick people are being treated without having given informed consent. Doctors are doing many things to the sick people that benefit the doctors without telling the sick people how bad those things are. If end-of-life doctors told the truth, they would have a lot less work.

The RadioLab podcast hints at the moral retardedness implied by this practice in an interview with a medical student, whom I assume was randomly chosen. Why aren’t people told the truth? the interviewer asks. “I don’t know how to communicate that effectively,” says the student. Then he communicates the truth quite effectively. Why don’t you say that? says the interviewer. People don’t want to hear that, says the student (changing his answer). They don’t want to, but they need to, says the interviewer. The student says it would be “presumptuous” to tell them the truth. Presumptuous. What universe is he in? The absurdities and pathetic justifications given by the medical student to rationalize his behavior suggest that the whole medical profession doesn’t understand there is a big problem.

The comments on the RadioLab podcast at the website also suggest that doctors fail to grasp there is a big problem. Many commenters are doctors. Some agree with the facts in the program. None expresses even discomfort with the situation. One commenter is Joseph Gallo, the Johns Hopkins medical school professor who runs the study that revealed the enormous difference between what doctors want and what the general public wants. “I second the sentiments about nurses being great,” wrote Gallo. “I would add that studies that have asked nurses about their end-of-life preferences have found similar desire to limit care.” The two sentences contradict each other. There is nothing “great” about anyone who sees this happening and does nothing.