Sometimes anxiety is just a normal reaction

IN THE US, almost half of the population is described as being in some way mentally ill, and 200 million prescriptions are written annually to treat depression and anxiety. These statistics have sparked a debate about whether people are taking more medication than is needed, for problems they may not have.

Those who defend such widespread use of prescription drugs insist a significant part of the population is under-treated and under-medicated. Those opposed note that, for example, diagnosis of bipolar disorder has rocketed by 4,000 per cent and that over-medication is impossible without over-diagnosis.

To help settle this dispute, I studied why the number of recognised psychiatric disorders has ballooned in recent decades. In 1980, the Diagnostic and Statistical Manual of Mental Disorders added 112 disorders to its third edition (DSM-III). Some 58 more appeared in the revised third and fourth editions. The manual is the bible of American psychiatry, and the addition of even one new disorder has serious consequences. So why add so many?

I was granted access to unpublished memos, letters, and voting data from 1973-1979 when the DSM-III task force debated each disorder. Some of the work was meticulous, but the overall approval process was more capricious than scientific.

DSM-III grew out of meetings that many participants described as chaotic. The expertise of the task force was limited to neuropsychiatry, and the group met for four years before it occurred to members that it might be biased.

Some lists of symptoms were knocked out in minutes and the field studies used to justify their inclusion sometimes involved a single patient. Experts pressed for the inclusion of illnesses as questionable as "chronic complaint disorder", whose traits included moaning about taxes and the weather.

Social anxiety disorder was given official recognition in 1980 and by the 1990s experts insisted as many as one in five Americans suffered from it. Yet Isaac Marks, the specialist who originally recognised social anxiety in the 1960s, resisted its inclusion as a separate disease. The list of behaviours associated with the disorder, such as avoidance of public toilets, gave him pause. By the time a revised task-force added dislike of public speaking to the symptom list in 1987, the disorder seemed sufficiently elastic to include virtually everyone on the planet.

To counter the impression it was turning common fears into medical conditions, DSM-IV added a clause stipulating social anxiety had to be "impairing" before a diagnosis was possible. But the prescribers' understanding of impairment was looser than that of the task-force.

Over-medication would affect fewer Americans if we could rein in examples of over-diagnosis by resurrecting the distinction between chronic illness and mild suffering. . Failure to reform psychiatry will be disastrous for public health. Sanity must prevail: if everyone is mentally ill, then no-one is.