Medicalization of ADHD is spreading globally, say researchers

The medicalization of attention deficit hyperactivity disorder (ADHD) has migrated in recent years from the United States to other countries around the world, a troubling trend that has more to do with marketing than with medicine, according to a paper published this week in the journal Social Science & Medicine.

Until fairly recently, write social scientists Peter Conrad and Meredith Bergey of Brandeis University, the United States was almost alone in having a large percentage of its children diagnosed with ADHD (11 percent, according to the latest statistics from Centers for Disease Control and Prevention).

But the rest of the world has begun to catch up. In Great Britain, for example, some 2-5 percent of school-aged children are now identified as having ADHD — a figure that’s up from less than 1 percent in the 1990s, according to Conrad and Bergey. And in Germany, prescriptions for ADHD stimulants increased fivefold within a single decade, rising from 10 million daily doses in 1998 to 53 million in 2008.

And then there’s this telling statistic: Until the 1990s, report Conrad and Bergey, the U.S. consumed 90 percent of the world’s supply of Ritalin, the signature pharmaceutical treatment for ADHD. By 2010, that proportion of use had dropped to 75 percent.

What’s underlying the global spread of ADHD? Conrad and Bergey point to the following five factors:

1. The expanded lobbying efforts of the pharmaceutical industry.  Since the 1990s, the pharmaceutical industry has been activity lobbying to expand its global markets for Ritalin and similar drugs — and with success. They have persuaded countries like Italy and France to lift prior legal restrictions on the sale of ADHD stimulants, for example. They have also stepped up their advertising efforts around the world, marketing directly to physicians and, when possible, to consumers.

Another key target market has been teachers. “Teachers often play an integral role in ADHD diagnosis and treatment due to the extended periods of time they spend interacting with children throughout the school year,” write Conrad and Bergey. “Teachers (as well as school nurses) are often expected to participate in diagnostic assessments in ADHD and may be involved in administering ADHD medication.”

2. The growing influence of U.S.-style psychiatry.  U.S. psychiatry favors biological approaches — treating psychological problems with drugs — rather than psychoanalytical ones, which emphasizes talk therapy. As a result, U.S. psychiatrists — and other physicians — tend to treat ADHD primarily with drugs. This emphasis on biological psychiatry has, in recent years, been spreading to other countries — helped in part, say Conrad and Bergey, by the fact that many non-U.S. psychiatrists, particularly child psychiatrists, are sent to the United States to be trained.

In addition, several “international consensus statements” on ADHD have been issued in recent years — documents that mostly attempt “to justify and encourage ADHD diagnosis and treatment,” say Conrad and Bergey. The international nature of these statements is questionable, however, as the signers are overwhelmingly from North America.

3. The growing reliance on the U.S. definition of ADHD. For decades, non-U.S. psychologists and psychiatrists have tended to rely on the World Health Organization’s “International Classification of Diseases” (ICD) manual for diagnosing psychological conditions and illnesses. In recent years, however, increasing numbers of them have been persuaded to use the American-based “Diagnostic and Statistical Manual” (DSM) manual instead. “The ICD denotes a condition called hyperkinetic disorder (HKD), which in many ways is similar to ADHD, but provides a somewhat different and higher threshold for diagnosing ADHD-like symptoms,” write Conrad and Bergey.

The DSM, for example, includes many more symptoms of hyperactivity (including “blurting out answers” and “difficulty waiting one’s turn”) than does the ICD. The DSM also allows a diagnosis if symptoms occur in only one setting (either at school or at home, for example), while the ICD requires that symptoms occur in at least two settings. Under the DSM, therefore, many more children — and adults — are likely to be diagnosed with hyperactivity.

4. The Internet. “The Internet knows no national boundaries and appears to be a major vehicle for ADHD diagnostic migration,” write Conrad and Bergey. Most of the information about ADHD on the Internet comes from the U.S. and other countries where the diagnosis of the condition is well established, and it frequently includes simple checklists for self-diagnosing. The questions on these lists are incredibly broad, such as “Do you fidget a lot?” “Is it hard for you to concentrate?” “Are you disorganized at work and home?” “Do you start projects and then abandon them?”

“These checklists turn all kinds of different behaviors into medical problems,” notes Conrad in a statement released with their paper. “The checklists don’t distinguish what is part of the human condition and what is a disease.”

5. Patient-advocacy groups. In recent years, many ADHD-related patient-advocacy groups have begun to appear in Europe and South American countries, groups that are similar to those already established in the U.S. They offer U.S.-style information (including self-diagnosing checklists) about ADHD, hold conferences that feature ADHD providers, and lobby government officials for greater access to treatments. Many of these groups, like those in the U.S., receive funding from pharmaceutical companies.

“It is ultimately unclear how far and wide the ADHD diagnosis will migrate,” conclude Conrad and Bergey. “… It is quite apparent, however, that ADHD diagnosis and treatment are on an increasingly global path. Our guess is that in a decade or less, the ADHD diagnosis will be more established and treated worldwide.”

You’ll find an abstract of the paper on the Social Science & Medicine website.