Andres Barkil-Oteo is an assistant professor of psychiatry at Yale University School of Medicine, with research interests in systems thinking, global mental health, and experiential learning in medical education. Find him on Google+ here.
Last spring, the American Psychiatric Association (APA) sent out a press release [pdf] noting that the number of U.S. medical students choosing to go into psychiatry has been declining for the past six years, even as the nation faces a notable dearth of psychiatrists. The Lancet, a leading medical journal, wrote that the field had an “identity crisis” related to the fact that it doesn’t seem “scientific enough” to physicians who deal with more tangible problems that afflict the rest of the body. Psychiatry has recently attempted to cope with its identity problem mainly by assuming an evidence-based approach favored throughout medicine. Evidence-based, however, became largely synonymous with medication, with relative disregard for other evidence-based treatments, like some forms of psychotherapy. In the push to become more medically respected, psychiatrists may be forsaking some of the important parts of their unique role in maintaining people’s health.
Over the last 15 years, use of psychotropic medication has increased in all kinds of ways, including off-label use and prescription of multiple drugs in combination. While overall rates of psychotherapy use remained constant during the 1990s, the proportion of the U.S. population using a psychotropic drug increased from 3.4 percent in 1987 to 8.1 percent by 2001. Antidepressants are now the second-most prescribed class of medication in the U.S., preceded only by lipid regulators, a class of heart drugs that includes statins like Lipitor. Several factors have contributed to this increase: direct-to-consumer advertising; development of effective drugs with fewer side effects (e.g., SSRIs); expansion in health coverage for mental illness made possible through the Mental Health Parity Act; and an increase in prescriptions from non-psychiatric physicians.
Unfortunately, not all of these psychiatric drugs are going to good use. Antidepressive drugs are widely used to treat people with mild or even sub-clinical depression, even though drugs tend to be less cost-effective for those people. It may sound paradoxical, but to get more benefit of antidepressants, we need to use them less, and only when needed, for moderate to severe clinically depressed patients. Patients with milder forms should be encouraged to try time-limited, evidence-based psychotherapies; several APA-endorsed clinical guidelines center on psychotherapies (e.g., cognitive behavioral therapy or behavior activation) as a first-line treatment for moderate depression, anxiety, and eating disorders, and as a secondary treatment to go with medication for schizophrenia and bipolar disorder.
The American Psychiatric Association have just published the latest update of the draft DSM-5 psychiatric diagnosis manual, which is due to be completed in 2013. The changes have provoked much comment, criticism, and heated debate, and many have used the opportunity to attack psychiatric diagnosis and the perceived failure to find “biological tests” to replace descriptions of mental phenomena. But to understand the strengths and weaknesses of psychiatric diagnosis, it’s important to know where the challenges lie.
Think of classifying mental illness like classifying literature. For the purposes of research and for the purposes of helping people with their reading, I want to be able to say whether a book falls within a certain genre—perhaps supernatural horror, romantic fiction, or historical biography. The problem is similar because both mental disorder and literature are largely defined at the level of meaning, which inevitably involves our subjective perceptions. For example, there is no objective way of defining whether a book is a love story or whether a person has a low mood. This fact is used by some to suggest that the diagnosis of mental illness is just “made up” or “purely subjective,” but this is clearly rubbish. Although the experience is partly subjective, we can often agree on classifications.
Speaking the same language
How well people can agree on a classification is known as inter-rater reliability and to have a diagnosis accepted, you should ideally demonstrate that different people can use the same definition to classify different cases in the same way. In other words, we want to be sure that we’re all speaking the same language—when one doctor says a patient has “depression,” another should agree. To do this, it’s important to have definitions that are easy to interpret and apply, and that rely on widely recognised features.
To return to our literature example, it’s possible to define romantic fiction in different ways, but if I want to make sure that other people can use my definition it’s important to choose criteria that are clear, concise, and easily applicable. It’s easier to decide whether the book has “a romantic relationship between two of the main characters” than whether the book involves “an exploration of love, loss and the yearning of the heart.” Similarly, “low mood” is easier to detect than a “melancholic temperament.”
Charles Figley was a US Marine who signed up for service in the Vietnam War to “accelerate my progression toward being considered a man.” But after his tour of duty he ended up as veteran protesting against the war, stunned by the psychological impact on himself and his fellow soldiers.
He began to investigate the symptoms of his fellow veterans and, along with other anti-war psychologists and psychiatrists, proposed a disorder called “post-Vietnam syndrome” where veterans carried emotions of the war with them despite being safely back on US soil. In fact, various forms of combat stress had been recorded during previous wars, from “disordered action of the heart” diagnosed in the Boer Wars to the dramatic symptoms of shell shock and war neurosis from the First World War.
The concept caught on and appeared, in a demilitarised form, as “post-traumatic stress disorder,” a mental illness where an earlier trauma causes the person to have a sense of current threat characterised by flashbacks, intrusive thoughts, avoidance of reminders, and anxiety.
And here lies the paradox. Researchers have noted that “PTSD is classified as an anxiety disorder. Within cognitive models, anxiety is a result of appraisals relating to impending threat. However, PTSD is a disorder in which the problem is a memory for an event that has already happened.” After all, if you feel threatened with good reason, almost by definition, this isn’t a mental illness.
So if someone remains in danger after a life-threatening incident, does the concept of “post-traumatic stress disorder” even make sense?