Explaining the Global Rise in ADHD Diagnoses

In the 1980s, one in 20 U.S. children were diagnosed with ADHD. Today, that number is roughly one in 9. This somewhat dramatic spike in diagnoses has led many in the media, the research community, and the population at large to ask, “Why is ADHD on the rise?” A recent study published in the journal Social Science and Medicine identifies five factors that authors Peter Conrad and Meredith Bergey believe are contributing to the global spread of ADHD:

1. Marketing — Medication companies have stepped up their advertising campaigns, directly targeting physicians and consumers whenever possible. They’ve also increased lobbying efforts around the world — in Italy and France, for example, they successfully lobbied the governments to remove restrictions on the sale of stimulants for the treatment of ADHD.

2. The influence of US-style psychiatry — Psychiatry in the United States leans more towards biological treatments of mental illnesses, while much of the world has traditionally favored talk therapy. In recent years, however, more and more non-US psychiatrists are traveling to the United States for training — leading to a spread of US-style psychiatric methods around the world.

3. The spread of the US definition of ADHD — In the United States, psychiatrists and doctors rely on the DSM (Diagnostic and Statistical Manual). In other countries, the World Health Organization’s International Classification of Diseases (ICD) is the book of choice for health professionals. The ISD has a much narrower definition of ADHD, leading to fewer diagnoses. In the past few years, however, the DSM has gained traction in international markets — linked again to the rise of US-trained psychiatrists around the world.

4. The Internet — Thanks to the World Wide Web, more people are aware of ADHD then ever before — and able to identify symptoms in themselves or their children. Self-tests are common, allowing people to go to their physician with an ADHD diagnosis already in mind.

5. Patient advocacy groups — Until recently, ADHD patient advocacy groups were primarily a US-based phenomenon. Now, however, they’re popping up across the world, from Europe to South America. Patient advocacy groups provide support and information to those who suspect they may have ADHD, and often host ADHD-themed conferences for patients and providers.

In short, the Social Science and Medicine article ties rising ADHD diagnoses to pharmaceutical marketing and loosening medical standards that they say over-medicate certain behavioral characteristics unnecessarily.

A huge number of medical experts and clinicians would vehemently disagree with this conclusion. There is real, medical evidence that ADHD is biologically based, and occurs as a result of an imbalance of chemical messengers, or neurotransmitters, within the brain. Dr. Stephen Hinshaw, author of The A.D.H.D. Explosion: Myths, Medication, Money, and Today's Push for Performance, disputes the article’s assertion that media and big pharma are to blame, saying, “The fragmented media we have today are responsible to some extent for everyone's partially fragmented attention, but this is clearly not the cause of ADHD.” He does not agree with the implied notion that United States diagnostic standards are looser than other nations’, or that the adoption of U.S. standards is increasing diagnosis rates worldwide. Rather, based on careful research using data from the National Survey of Children’s Health conducted by the Centers for Disease Control and Prevention (CDC), he finds evidence that the higher rates of diagnosis in the United States are due to the education system and government policies dictating academic standards.

Furthermore, Dr. Hinshaw and his team conducted a detailed analysis that revealed particularly high rates of diagnosis in the South and Midwest, alongside a high percentage of children treated with ADHD medication in the same locations. Further analysis showed that public school students living near the federal poverty level saw the steepest increase. The states with the highest rates were among a group that scrambled quickly to meet new educational standards when “No Child Left Behind” became law. Their funding was suddenly dependent on progress in collective student test scores for the district, so the districts were under pressure to perform. It was during these years that the surge in diagnosis occurred. After 2007, when the school accountability patterns changed with “The Race to the Top” legislation, the rate of diagnosis in the poorest public school children tapered off.

“It may be that certain school districts were quite interested in the poorest-achieving kids in those districts getting a diagnosis because, now, treatments could be delivered,” Dr. Hinshaw says. “The kids could get special education or accommodations or the kids might get medication. We know that, for carefully diagnosed kids with ADHD, medication doesn't just reduce fidgetiness, but can actually increase and enhance test scores for the first year or so of treatment.”

Learn more about Dr. Hinshaw's research regarding ADHD diagnoses and U.S. education standards.