Friday, February 24, 2012

Problems with Irving Kirsch's Critique of Antidepressants as Placebos

Recently, a FB pal posted an article run on 60 Minutes based on the work of Irving Kirsch. He's a psychologist who has been making the rounds saying antidepressants don't work - and, indeed, depression is not caused by a chemical inbalance at all. It's a pretty radical claim. The overwhelming medical belief is that antidepressants do more good than harm by a considerable margin. Kirsch believes otherwise. To quote him, "Depression is not a brain disease, and chemicals don’t cure it.”

(I'm not going to provide links, here, because linking is largely meaningless. You can find someone on the Internet to take virtually any position at all, so links that "prove" a given point do nothing of the sort - they merely show the person can search around for data that agrees with their conclusions. I encourage people to do independent and substantial research on any field that interests them and advise they read books to do it. The Internet has certainly broadened our knowledge, but it has also made much of it shallow and muddy.)

I've been following Kirsch's work for about a year, now. This is shortly after I started taking antidepressants and feeling considerably better - so I had some vested interest in the research. Was the effect I feeling a placebo effect?

For the record, I am extremely critical of psychological research for both historical and theoretical grounds. I think this bias is justified - psychology has not done a very good job of policing itself. The case of Cyril Burt is particularly significant. But was a psychologist who did twin studies. After his death, it was found he had massively falsified his information, lying about the sample size of the twins studies he did, inventing collaborators and their credentials - this has not prevented his work from continuing to be taught. This is unprecedented. I can't think of a single case where a person, caught committing fraud over the span of decades, would still be taught. The articles "known" to be fraudulent have been removed, but if there was no direct "proof" that a given paper was fraudulent it has remained in the academic canon. (Such proof is hard to get, because Burt burned all his notes before he died!) Furthermore, due to the vagaries of attribution inheritance, articles whose substance is based on Burt's findings are still part of the psychological data record - no effort was made to purge the effects of his fraudulent work from the data pool.

I wish I could say this was something that died with Burt. But you can find the continuation of such fraud in psychology in books like The Bell Curve, issues like gender studies and evolutionary psychology - not to mention, like I said, Burt's work has not been purged from the psychological canon; while those papers known to be fraudulent have been removed, the papers that source Burt's work were not and are themselves sourced by modern research.

(An interesting comparison between corrupt scientific fields and how they clean themselves up, or in psychology's case, fail to, is anthropology. Anthropology was, sadly, very much part of the early twentieth century's eugenics movement. After World War II, though, anthropologists, horrified at what they had helped to do, given intellectual weight to atrocity, purged eugenics from its discipline almost entirely. Psychology, whose IQ tests were also used to justify eugenics, who were equally guilty of giving intellectual force for the eugenics massacres of the early twentieth century, well . . . the Bell Curve is still influential. The eugenicists are still there in psychology, they were never purged or repudiated. In short, there is no psychology equivalent to Jane Goodall because the field never cleaned it's house after World War II.)

Theoretically, psychology is a mess. (And by theory, I'm talking about theory in the scientific jargon sense, which is an explanation for diverse phenomenon inside the field of study, demonstrated by considerable proof without substantial internal contradiction.) It is the only science that has no generally accepted theory regarding the field's object of study. This is a very simple statement, but the consequences are enormous. In short, psychologists are not in agreement, at all, as to what the mind actually is. When compared to chemistry's atomic model, astronomy's relativity, biology's natural selection, physics' mechanics and quantum mechanics, so forth and so on, this lacuna is enormous. If you don't agree about what it is you're studying, how on earth can you study it? What, precisely, are you studying? They literally cannot agree.

(This is in contradistinction to psychiatry, which has a very strong, stable theory of mind. Your mind is your brain, they are one in the same. It is a theory for which there is tremendous evidence, of course.)

So, when I read psychological research, I do so with a grain of salt. They have a lousy track record of policing themselves, the worst in science, and no unifying theory!

Well, when you look into Kirsch's work, it's actually pretty atrocious. Not the hypothesis, so much as his methodology and, indeed, his theoretical understanding of human consciousness.

I'm going to tack the methodological failures of his work. In particular, he cherry picked data. For instance, in the APA journal Prevention and Treatment, where much of his early work was published, the editor of that journal called Kirsch's statistical models "clearly arguable" and warned that his paper's subject-selection criteria were heterogenous. In particular, Kirsch only looked at short term studies.

Now, I do not doubt that antidepressants are overprescribed - but prescribing drugs is what doctors do. Most physicians take the attitude that it's better to ere on the side of caution. Because of the difficulties in communicating psychological conditions, when a patient comes in and says they've been depressed for a long time and nothing seems to pull them out of it - what is the psychiatrist to do? Ignore the suffering of their patient? No. They prescribe medication and usually suggest therapy. After all, antidepressants are generally safe.

In many of these cases, however, the depression wasn't clinical. It's not even that the medication acted as a placebo - it's that there was no illness in the first place. So when Kirsch argues, on the grounds of short term studies, that there is substantial placebo effect - he's wrong. It wasn't the medication or the placebo effect that halted the depression; it was just the normal passage of time in an unknown number of cases. How can this be construed as data at all?

For instance, you take a group of people with headaches. Half you give ibuprofin, half you give sugar pills. An hour later, you ask them how they feel and find that almost all of them, in both groups, now feel fine, most of them attributing their improvement to their medication. Out of these groups, how do you find the people whose headaches just stopped naturally, as most headaches do? It's the same with short term depression studies. It is impossible to determine how many of the people felt better not because of the medication or of the placebo.

In psychiatric and psychological studies, there is tremendous self-selection of subjects. People who feel bad tend to join. While in most medical science, they can perform an actual test to determine who has the condition for which they are testing (say, a virus), this is not generally possible in psychological and psychiatric cases in the short term. So it is known that many of the people who join psychological and psychiatric studies aren't sick in the first place, but it's impossible to know how many! How can you determine the efficacy of the placebo effect if you don't even know if they're clinically ill in the first place? The only good method of determining a person's psychological state is long term observation - something impossible to do with short term studies. By avoiding long-term studies, Kirsch is avoiding the very data that would counter his hypothesis. Ouch. That's a huge scientific no-no.

Additionally, the placebo effect is, itself, short term. The longest known placebo effect is two and a half years. Any study that goes over that is just assumed to be free of placebo effects. So, not only does Kirsch avoid the studies that select out the mentally ill from the temporarily distressed, he also avoids studies where the placebo effect is eliminated or minimized due to the long term nature of the studies. Double whammy.

Indeed, the very idea of the placebo effect is itself under fire - using methods similar to Kirsch's, but with larger data sets over longer periods of time, Asbjørn Hróbjartsson and Peter Gøtzsche have basically demonstrated that there is no clinically significant placebo effect. So, who's right? Kirsch who says that antidepressants are placebos or Hróbjartsson and Gøtzsche who say that the placebo effect is clinicially insignificant?

This is awful methodology. It's simply scientifically unethical to ignore the data that contradicts your conclusions, to study only those things that allow you to be right. To have scientific legitimacy, Kirsch must address long term studies that are free of the placebo effect and the growing body of evidence that the placebo effect is not clinically significant. He does not do this.

One might ask, then, why he can get these high falutin' jobs, like the University of Leeds and now, well, he works at Harvard. Remember what I said about Cyril Burt, The Bell Curve and evolutionary psychology - psychology is a field full of quacks, even at the highest levels of education and research.

Not to mention this is a highly politicized area. There are a lot of people who simply reject the idea that mental illness has a physical component. I'll talk more on that in a bit, but my point here is that there are a lot of people who actively reject the idea of mental illness, who believe that mentally ill people should "pull themselves up by their bootstraps", or seek solace in religion, or "just get over it". (Thomas Szasz published, in 1961, The Myth of Mental Illness - a book that was just reprinted last year and still has considerable influence; see also The Manufacture of Madness and more recently The Manufacture of Depression, which came out last year - and it goes back as far as the written language goes - there are always people who say mental illnesses don't really exist, you can read about it in medieval sources, in classical antiquity; Pythagoras said that depression was merely lack of self control, akin to laziness; Hippocrates believed that melancholia - what we call depression, nowadays - was an imbalance of the four humors, which is to say a medical problem. This argument is ongoing, but nowadays is largely farcical. The medical basis of mental illness is well understood.) They are emboldened by a researcher like Kirsch, who gives the air of legitimacy to their beliefs.

Science is not some purely intellectual field - it takes money to do it, and the people in charge of that money are not, by and large, scientists. They are corporations and political bodies, pursuing their own agendas. But no one brings it up that there are non-scientific social forces that reject mental illness for no good reason - but then use their status in order to support research in that area. As an example, the University of Oklahoma's geology department is the ConocoPhillips School of Geology and Geophysics. Guess what their position on global climate change is? This is as true in psychology as geology - people with social and political agenda control research funding and publication. And there have always been people who are swift to side with people who say that mental illness isn't physical, that it's a defect in will or character. It goes back at least as far as Pythagoras and Hippocrates!

Additionally, there's just the prima facie stupidity of asserting that you can effect mood with drugs. I mean, prima facie. There are a huge number of studies about the effects of drugs on mood, not to mention nearly every adult reading this has personal experience with alcohol lifting their spirits and lowering their social anxiety. Even more powerful are the opiates - it is impossible to be depressed when you're on Percocet. Unfortunately, these drugs have such dangerous side effects that it is unethical to administer them or they must be administered very carefully. But it's absurd to say that drugs can't effect mood and feelings. It's silly and juvenile! The only question is to what extent does a given drug effect our feeling of depression. That drugs can alter our feeling of depression is simply prima facie true.

The aquisition of funding and possession of high titles does not make a person right. It only means that someone in a position of power agrees with what you say and is willing to give you money to prove it. While it shapes all scientific endeavors to some degree, it is particular pernicious in a field where there is no theory. In psychology's theoretical void, their lack of agreement about what the mind is, anything goes. So you come up with racist crap justifying eugenics and people doubting the physiological origins of mental illness.

Which brings me to the theoretical problems I have with Kirsch's work and all work that supposes a mind/body dualism. Kirsch believes that depression isn't a brain disease. Well, for crying out loud, man, what kind of disease can it be, then? Because all the actual evidence suggests that the mind and the brain are the same thing. All mental activity - thought, reason, emotion, perception - they're all brain activity. If depression exists at all, it must exist as a brain disease because that's where the mind is located. To say that you believe that depression exists but isn't a brain disease makes as much sense as saying you believe in heart attacks but it's not a heart disease.

But we live in a world that is steeped in dualism - the belief that there is some sort of perfected, non-physical sense that exists independent of our flesh. Sometimes it's called the soul, but just as often it's called the mind and the two are mixed up in religion and culture all the time. Dualism is present in all the world's largest religions.

However, that's not science. Science has never been able to find a soul. It has never been able to find a mind separate from the brain. Meaning, Kirsch is proposing something preposterous, again: that you can have a mental illness that isn't in the brain.

I can't say it's short, but those are my main reasons for thinking Kirsch is a quack.

3 comments:

  1. Why must depression be a disease? There is no proof that depression is a disease or an illness. If depression is a disease then so should be sadness, anger, and misery. Depression is only a disease if you re-define the term from its scientific bio-medical antecedents. Depression is a disease in the same way that a joke can be 'sick': metaphorical. That's all psychiatry amounts to really, a confusion between the actual meaning of disease and its metaphorical usage.

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  2. That's kind of like saying "why is cancer a disease?" It also demonstrates your basic lack of understanding of the history of medicine. Depression has *always* been regarded as a medical condition by physicians, literally going back to Galen and his ancient peers. There is no time period where depression has *not* been regarded as a disease.

    Additionally, every scientist I've talked to about the subject talks freely about the two main biological causes of depression - serotonin reputake and lack of dopamine. That it is neurochemically caused is simply indisputable *scientifically*. Unless, y'know, you choose to regard quacks as being more knowledgable than medical consensus for the past 2500 years.

    Seriously, the evidence for depression as a pathological condition is overwhelmingly present. To say otherwise is either a sign of ignorance or cruelty.

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