Daniel Carlat, an associate clinical professor of psychiatry at Tufts University, wrote a two-part review of Anatomy of an Epidemic on January 21 and 24. His review was quite genial in tone, and I appreciated it. Here are his stated criticisms, along with my response.
1. I mistake correlation for causation.
Dr. Carlat states that while it is true that many more people are taking psychiatric drugs today and that many more people are on disability due to mental disorders, this does not mean that the medications have caused the rise in disability. Other reviewers have made this same criticism.
I agree that the correlation between the two—increased use of psychiatric medications and increased disability numbers—does not mean that the increased use of psychotropics caused the rise. But I never claimed that it did. As I note in the opening chapter, page 9, the disability numbers simply raise a question. Here’s what I wrote:
“Could our drug-based paradigm of care, in some unforeseen way, be fueling this modern-day plague? My hope is that Anatomy of an Epidemic will serve as an exploration of that question.”
I then spend the next 200 pages or so reviewing the history of the outcomes literature for major mental disorders (and childhood disorders), with the hope of answering these two questions:
a) How do psychiatric medications affect the long-term course of major mental disorders (in the aggregate.) Do they improve the long-term course, or worsen the long-term course?
b) Is it possible that a person with a milder disorder may have an adverse reaction to an initial psychotropic medication, and in that manner move to a more serious diagnosis? For instance, is it possible that a person suffering from a mild bout of depression might have a manic response to that medication, and thus move onto a bipolar diagnosis? If so, that would be a mechanism for increasing the number of people with a serious mental disorder.
It is only through that review of the outcomes literature, with an eye on answering those two specific questions, that you can determine whether the medications may be fueling an epidemic of disabling mental illness. So I am being criticized here for mistaking correlation for causation, even though I explicitly stated, at the outset, that the correlation simply raised a question.
2. The rise in disability numbers is due to other factors.
Dr. Carlat, in his January 21 post, lists three reasons (other than meds) for the rise in disability. He attributes it to an increase in the number of diagnostic categories, an increase in the availability of treatments, which leads doctors to look for more diseases to diagnose, and changes in federal law that have encouraged more people to apply for disability.
As I noted on page 208 of Anatomy of an Epidemic, there may be a “number of social factors” contributing to the epidemic. As for the three factors he has cited here:
a) An increase in diagnostic categories may be helping to fuel the epidemic.
I agree. The broadening of diagnostic categories has invited an ever-greater number of adults and children into the “psychiatric tent”, so to speak. But if psychiatric medications were effective long-term treatments, which helped people function well, then that increase in diagnosis and treatment shouldn’t lead to a rise in disability. (Imagine that there is an infectious disease in a population that isn’t being treated, and then you develop an effective drug for that illness. The toll that disease takes on the population should drop, not rise.) But if you have drugs that exacerbate the long-term course of an “illness” or can transform a milder illness into a more serious one, then the more that illness is diagnosed and treated, the greater the toll that illness will take on society. Thus, increased diagnosis plus harmful long-term treatment becomes a one-two punch for increasing the disability numbers due to an illness.
b) An increase in the availability of treatments is encouraging doctors to look for diseases to diagnose.
Once again, if there are newly developed “effective” treatments for diseases that previously went undiagnosed, then the treatment of such diseases should not lead to diseases coming to take an ever greater toll on society. The increased recognition and effective treatment of a disease should reduce the toll it takes on society, not increase it.
c) Changes in federal law have encouraged more people to apply for federal disability.
I agree with this. I do believe that welfare reform in the 1990s, which made it so much more difficult for the poor to collect a welfare check, led many people to look to the federal disability system as a replacement source of income.
Even so, there still remains the question: What about the medications? Do they improve or worsen long-term outcomes? Do they sometimes cause people with a milder initial disorder to become more seriously ill? I believe that the long-term outcomes literature show that the drugs worsen long-term outcomes (in the aggregate), and that, on occasion, they can transform a milder illness into a more serious illness. As such, I believe that the evidence shows that the widespread use of the medications is helping to fuel the epidemic of disabling mental illness. It’s not the sole cause, but it’s a primary cause.
3. In my review of the schizophrenia literature, most of the studies I cite are “old,” and the patients who were diagnosed with schizophrenia in those older studies did not have the illness (as defined by the narrower definition in DSM-III).
As I sought to assess how medications affect the long-term course of a major mental disorder, such as schizophrenia, I followed a very straightforward process. First, I sought to flesh out the course of the disorder prior to the pharmacotherapy era. That served as something of a baseline for the illness. Then I tracked the scientific literature for that disorder over the next 50 years, looking for whatever relevant evidence that I could find. I looked for randomized studies that lasted for a longer period of time. I looked to see if, at the time the drugs were introduced, clinicians noticed any change in the long-term course of their patients. I looked to see if researchers, at some point, noticed that something was going awry with the long-term use of these drugs. If so, I looked to see if they put forth a biological explanation for why the medications might worsen the long-term course of the disorder. I looked at cross-cultural studies, and any naturalistic, longitudinal studies I could find. I looked at whether MRI studies showed that the drugs might be causing changes in the brain that, over the long-term, might be harmful. And on and on, ultimately what I was looking for was this: Did all of these pieces of evidence, gathered from a 50-year review of the research literature, come together to tell a convincing story?
And here was my biggest surprise when writing the book: Time and time again, those various pieces of evidence did come together to tell a coherent story.
Indeed, in response to Dr. Carlat’s criticism here, I encourage readers to closely read chapter six of Anatomy of an Epidemic, which is the chapter that looks at the long-term effects of antipsychotics on schizophrenia and other psychotic disorders. You’ll see a story start to emerge with the first one-year study conducted by the NIMH, in the 1960s, and then you’ll see that same theme—that antipsychotics might be worsening the long-term course of schizophrenia and other psychotic disorders— appear again and again in the literature. You’ll see it in the few randomized studies conducted in the 1970s. You’ll see that in the late 1970s and early 1980s, researchers put together a biological explanation for why antipsychotics might induce “new and more severe” symptoms over the long-term. You’ll see this theme in the WHO study comparing outcomes in developed and developing countries . You’ll see it in MRI studies, and in Martin Harrow’s long-term follow-up study, which was published in 2007.
The important thing here is that the conclusions drawn in Anatomy of an Epidemic do not arise from any one type of study. They arise from this larger history of science, which tells a consistent and powerful story that stretches across 50 years.
4. Most of the studies I cite are observational studies, which are suggestive, but not definitive.
See answer above. I do cite observational studies, but they simply are one type of research that I cite.
And here is one other thing to remember. In medicine, those who provide a treatment are expected to have evidence that the treatment is safe and effective. That arises out of the “Do No Harm” principle. Thus, after 50 years, one might think that psychiatry could point to a clear line of evidence showing that its medications improve the long-term course of major mental disorders. But where is that evidence? Psychiatrists reviewing Anatomy of an Epidemic have sought to explain away the book, or criticize my interpretation of findings. However, the field should be able to lay out a very succinct rebuttal. It should be able to say, here is the extensive research showing that psychiatric medications improve long-term outcomes, and help people function well. But such evidence has not been put forward as a “refutation” of Anatomy of an Epidemic.