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In the DSM, if you have five of the nine symptoms of depression, you have the same “major depressive disorder” as a person with all nine. This parallels other kinds of medical diagnosis: If you have a small Stage 1 tumor in your lung, you have the same disease as someone who is about to die from lung cancer.
But as Regier’s numbers made clear, doctors using DSM checklists were all too likely to find disease everywhere they looked. There was no governor in the mechanism, no way to say this person was sick and that one was simply unhappy, nothing like the CT scan that shows a persistent cough to be caused by a lung tumor. A doctor who diagnosed, say, strep throat entirely on the basis of symptoms, rather than availing himself of the quick and easy lab test for the disease, was practicing bad medicine. But a doctor who diagnosed depression only on the basis of symptoms was practicing standard psychiatry.
The comorbidity rates—the frequency with which people qualified for more than one diagnosis—were another embarrassment. Here again, Regier said, the ECA studies pointed not so much to a sick population as to a flawed set of criteria. Robert Spitzer, the leader of the DSM-III revision in 1980, had anticipated the possibility of multiple diagnoses, and in the introduction to that book he suggested that there was a hierarchy of mental illness, that some disorders only had a narrow range of symptoms while others contained multitudes. Schizophrenia, for instance, was far more encompassing than major depression, so clinicians confronted with a patient presenting symptoms of both were advised to render only a schizophrenia diagnosis on the assumption that the low mood was part of the more comprehensive disorder.
Regier countered that this amounts to a claim that depression itself is “just noise,” of no inherent interest or value in understanding the patient or his disorders. The ECA team found that people with symptoms of both schizophrenia and depression were different from people with only schizophrenia in many ways. Ignoring their depression meant failing to paint a complete diagnostic picture and losing “an enormous amount of data” about mental health. “The ECA blew the hierarchy out of the water,” Regier says proudly. “It just didn’t make any sense when we started looking at the data.”
Such concerns led the APA to abandon the hierarchy model of DSM-III-R (a limited 1987 reworking of the manual). But the real problem, Regier tells me, was not the approach but something much more basic: the idea that DSM disorders are discrete diseases that exist in nature in the same way as cancer and diabetes. To Regier, this is the original sin, the flaw that accounts for the high rates of both prevalence and comorbidity. “It makes it seem like an anxiety disorder doesn’t have any mood symptoms and a mood disorder doesn’t have any anxiety symptoms,” he said. “But it isn’t that simple. It’s just not the way people present.”
But it is the way the DSM continues to present mental illness; indeed, that neat separation is the signal innovation of the DSM-III. Fortunately for Mirin and Regier, by the time of their fateful meeting with the Post editors, they’d turned their skepticism into a strategy.
“We walked them through how we understood mental illness, and what our thoughts were about diagnosis and the DSM,” Mirin recalls. Not, of course, their thoughts about the book’s failure to correspond to clinical reality or about the way the categorical approach trapped diagnosticians in a tautological loop (which, after all, were highly technical matters, known and understood only by experts), but rather their thoughts about the troubles reported in the daily paper that might make the average editor skeptical: the shifting sands of psychiatric diagnosis, the prevalence rates, the frequent and repeated revisions of the nosology, the disorders that came and went with dismaying regularity. These they readily acknowledged but then turned to their advantage.
The problem, they said, wasn’t that psychiatry was inexact when compared with the rest of medicine but rather that the rest of medicine was nowhere near as certain as it was cracked up to be. The glucose levels that constitute diabetes, the cholesterol counts that call for treatment, the blood pressure that qualifies as hypertension—these numbers had all changed over time as well, and after no small amount of wrangling. To hold psychiatry to a more stringent standard was unfair, making victims of doctor and patient alike.
It was the perfect approach for an audience of journalists. “They were smart people,” Mirin says. “They were sophisticated enough to understand that what their doctor told them about hypertension was not carved in stone, either.” If the Post’s editors noticed the intellectual sleight of hand at work here, the way these leading psychiatrists were distancing themselves from the claims to certainty that had allowed the DSM to rescue psychiatry from the pseudoscience precipice, they didn’t say, at least not in print. Perhaps they were afraid they’d seem unsophisticated.
Either way, six days after the meeting, the paper came out in favor of parity, Congress passed a limited version of the bill, and mental health professionals everywhere rejoiced. Six years and many editorials later, parity became the law of the land with the Mental Health Parity and Addiction Equity Act. Mirin and Regier’s strategy succeeded. They had spun the dross of diagnostic uncertainty into gold.
Overselling the Prevalence of Mental Illness
Maybe you think Mirin and Regier were just trying to have it both ways, in which case you might still think those prevalence numbers are a little fishy. You might wonder what would happen if 25 or 30 percent of the population exceeded the standard glucose or blood pressure thresholds, but only 19 percent of that group—about 5 percent of the population—ever got sick enough to show up at a doctor’s office. Wouldn’t that state of affairs cast doubt on whether those numbers measure disease at all, raising the possibility that the whole idea of hypertension or type 2 diabetes had been cooked up an industry eager to sell treatments?
You might also point out that, regardless of whether they are diseases in themselves or only risk factors, blood pressure and glucose levels can at least be measured with a high degree of certainty. And you might then ask whether it’s really fair to compare conditions such as high glucose and blood pressure to mental illnesses, whether telling a patient he has hypertension for which he should take diuretics is really the same kind of intervention as telling him he has a chemical imbalance that antidepressants will correct.
Darrel Regier would have an answer for some of those questions. You think those numbers are high? Well, he would tell you, you should see the Midtown Manhattan Study. Regier started his training with the people who ran that project, which began in 1952, took 10 years to complete, and was conducted exactly where you think it was. Researchers canvassed 1,911 Manhattanites and concluded, according to Regier, that 85 percent of the population had a mental illness.
The Midtown Manhattan Study is a talking point for most defenders of the DSM. They cite that 85 percent number as evidence that even if the DSM is an imperfect document, and even if it catches an improbable number of people in its diagnostic net, at least it’s better than what we had in the bad old days. We in the mental health business call this a “downward comparison,” and we sometimes recommend one to our patients to help them put their problems in perspective. “Yes, it’s true your wife left you for your next-door neighbor,” you might say, “but at least your kids won’t have to commute as far as most children of divorce.”