Seth's Blog

Marcia Angell, a former editor of JAMA, may be the most prominent critic of drug companies. The most recent two issues of the New York Review of Books contain a two-part critique by her of psychiatry. I liked Part 1 because she described the excellent work of Irving Kirsch (The Emperor’s New Drugs). Part 2, however, is a disaster.

She goes on and on about the evils of the DSMs — the diagnostic manuals of psychiatry. Improving the reliability of diagnosis is playing into the hands of the drug companies, she seems to say. She complains that the number of diagnoses is increasing. Well, yes, all diagnostic systems get larger over time. This is a good thing; if you don’t have a name for a problem, it is hard to do cumulative research about it and hard to communicate research results to everyone else. She complains, apparently, that new categories are being added:

There are proposals for entirely new entries, such as “hypersexual disorder,” “restless legs syndrome,” and “binge eating.”

She does not say why this is bad. Maybe she thinks it’s obvious. It isn’t obvious to me. Diagnostic categories help researchers and doctors and the rest of us communicate. For example, Dennis Mangan’s research shows why it is a good idea for the term restless legs syndrome to have an agreed-upon meaning.

She complains that the DSM doesn’t have enough “citations”:

There are no citations of scientific studies to support its decisions. That is an astonishing omission, because in all medical publications, whether journal articles or textbooks, statements of fact are supposed to be supported by citations of published scientific studies. (There are four separate “sourcebooks” for the current edition of the DSM that present the rationale for some decisions, along with references, but that is not the same thing as specific references.)

Please. This is clueless. A diagnostic manual is a dictionary. It assigns meanings to diagnostic categories. You can make a useful dictionary without “citations of scientific studies”. Long before you can do scientific studies about the best way to define dog you can come up with a definition of dog that is better than nothing.

She ends her review with this:

Above all, we should remember the time-honored medical dictum: first, do no harm (primum non nocere)

Gag me with a spoon. Time-honored? Doctors — with the support of JAMA, not to mention the rest of the health-care establishment — continually prescribe drugs with bad side effects and high prices and suppress innovative alternatives. (Not only that. My own surgeon recommended a dangerous surgery of no clear value.) How they can claim to do no harm escapes me.

Sure, psychiatry is awful. For a long time psychiatrists rallied around a transparent intellectual fraud (Freud and his offshoots). Now they rally around a less transparent intellectual fraud (neurotransmitter theories of mental illness). Psychotherapists and their wacky theories and no-more-effective treatments are no better so I wouldn’t blame the drug companies for the underlying problem. I put the problem like this: Our health care system consists of a very large number of people, many with very large salaries, who must get paid. Being human, they strongly oppose any progress that would reduce their salary or influence or, heaven forbid, eliminate their job. Because of them, many promising lines of research, such as prevention via environmental change or cure via nutrition, are completely or almost completely ignored. This is the fundamental reason Angell’s critique is so bad: She is part of the problem. She is very smart, but she’s been brainwashed (“primum non nocere“!). She utterly ignores the fact that we don’t know what causes depression, what causes schizophrenia, what causes autism, and so forth. Only when we learn what causes these and other mental disorders will we be in a good position to improve our mental health.

In a recent interview, Tim Harford, the Underground Economist, said,

That’s what makes medicine such an effective academic discipline.

By “that” he meant certain methodologies, especially randomized experiments. I disagree with this assessment. My opinion is that health care is in a state of profound stagnation, unable to make much progress on major problems.

Here are six signs of the stagnation in health care (by which I mean everything related to health):

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This article by Eoin O’Connell reports a study in the American Journal of Clinical Nutrition (the top nutrition journal) that found a correlation between meat consumption and weight gain: The more meat you ate, the more weight you gained over five years. Meat is fattening! reported several newspapers.

Mr. O’Connell did something unusual for a health journalist: He thought for himself. I don’t mean he applied a formulaic criticism (e.g., “correlation does not equal causation”). That’s not thinking, that’s knee-jerking. Mr. O’Connell read the paper. And he noticed an interaction: The correlation between meat consumption and weight gain depended on activity level. The study involved about 400,000 people. The researchers put each person in one of four activity levels: inactive, moderately inactive, moderately active, and active. There was a correlation between red-meat consumption and weight only for the two most active groups (moderately active and active). The original article reported that this interaction was significant:

The relation between red meat and weight gain was also stronger in physically active subjects compared with moderately inactive or inactive subjects (P values for interaction = 0.02)

The obvious implication of this interaction, as Mr. O’Connell says, is that meat caused muscle gain. Weight differences between more-meat and less-meat eaters were due to differences in muscle mass. This puts an entirely different spin on the results. The alternative explanation is quite plausible. I once had a grad student who was a vegetarian. When he was an undergrad, he told me, he and his roommate would go to the weight room and do similar sets. His roommate, who ate meat, rapidly gained muscle; he did not. Of course, meat = animal muscle.

Mr. O’Connell continued to the really interesting part of his article:

Perhaps not so surprisingly, the consideration that muscle is a form of weight gain does not appear in the newspaper articles but much more surprising is the fact that it does not appear in the original journal article either.

The AJCN article has fifty authors. Not one of them, apparently, noticed this all-important point! Nor did the reviewers for this prestigious journal. The article concludes: “Our results are therefore in favor of the public health recommendation to decrease meat consumption for health improvement.” No, they’re not, if the more meat, more muscle explanation is correct.

Most prestigious journal. Fifty authors. Huge expense. Total F-up in the sense that the final conclusion is probably wrong. (To be fair, the paper has plenty of value in other ways.) Congratulations, Mr. O’Connell, for noticing.

You have surely heard the phrase economies of scale — meaning that when you make many copies of something each instance costs less than when you make only a few copies. Large companies are said to benefit from “economies of scale” — so there is pressure to become bigger. Every introductory economics textbook says something like this. (more…)

The notion that high cholesterol (more specifically, high “bad” — LDL — cholesterol)  causes heart disease may be as widely accepted as the notion that humans have caused dangerous global warming. It is much easier to test, however. An excellent study published in 2006 compared two groups of people at risk for heart disease: those given a high dose of statins and those given a low dose. The high dose reducd LDL cholesterol levels; as it was meant to; the low dose did not. But there was no effect on coronary heart disease progression. After a year of statins, persons in both groups had increased their coronary artery calcification score by the same amount — about 25%. Totally contradicting the cholesterol hypothesis.

Regular readers of this blog may remember that after a year of eating butter (half a stick per day), my coronary artery calcification score decreased 24%. Because increases of about 25% are the norm, my score was about 50% less than expected. Decreases are very rare, I was told.

Thanks to Hyperlipid. Statin side effects.