Children who are younger than their classmates are most likely to get the label.
Children who can’t keep still in class, especially boys, are ever more likely to receive a diagnosis of attention deficit hyperactivity disorder (ADHD). That’s especially true if they’re younger than their classmates.
As children get older, they typically calm down and become more able to focus at a desk. So comparing older kids to younger ones could easily make the young ones look abnormal. It’s also possible that kids who are the oldest in the class but suffer from ADHD aren’t being identified because they look calm compared to their younger classmates.
But the overall trend is for more children to be diagnosed, correctly or not. In the latest available report from the Centers for Disease Control and Prevention, parents reported in 2011 that 11 percent of school-age children had received a diagnosis of ADHD at some point, up from less than 7 percent in 2003. Those numbers have risen each year by about 5 percent. About 6 percent of school-age children currently take an ADHD medication.
Getting an early diagnosis is a good thing, assuming a child actually needs help, observes Michael Manos, head of Cleveland Clinic Children’s ADHD Center for Evaluation and Treatment. But the diagnosis may be a bit of a fad, sometimes driven by anxious or frustrated parents. “When you take people who are in a 15-minute pediatric primary care physician’s office visit, and the mother describes hyperactivity and the physician automatically prescribes medication, that’s a problem,” he said.
Parents may simply be frustrated by kids who aren’t meeting their expectations. Take the case of one 12-year-old boy who came to Teachers College Dean-Hope Center for Educational and Psychological Services to be evaluated for learning problems. His parents believed he had ADHD; his grades were mostly Bs and they thought he was smart enough to earn As. The Teachers College team noted that he was able to pay attention for two-hour sessions of testing. Also, he was doing well in some areas, which meant he could focus when he chose. Their bottom line: He didn’t have ADHD.
Teachers College professor Steve Peverly, PhD, observes that many children are misdiagnosed with academic problems like dyslexia or attention deficit disorder, when they are actually normal. Sometimes they are distracted by family problems like recently separated parents, new family members, or lack of privacy.
The misdiagnosis problem may be becoming global. In Taiwan the cut-off for entering school is a birthday in August. When researchers there recently examined data for nearly 400,000 children ages 4 to 17, they found that 4.5 percent of students born in August were labeled ADHD, compared to 2.8 percent of students born in September, who were in the grade behind them and the oldest in their classes.
The Taiwanese researchers set out to test evidence that has shown up in other countries. In one of the largest American studies, among children who were the youngest in their kindergarten class, 8.4 percent had been diagnosed with ADHD, compared to 5.1 percent of the oldest children in their grades. The study drew on data on nearly 12,000 children from government surveys of parents and teachers of kindergarteners in the fall of the 1998–1999 school year, who were contacted again several times through eighth grade. Teachers were more likely than parents to report problems with children who were young for their class. The author, an economist, observed that if birth date was irrelevant, 20 percent of the children identified as having ADHD had been misdiagnosed and may be taking medication unnecessarily.
ADHD medications are stimulants with side-effects: They raise pulse rates and blood pressures and can stunt growth. A two-year randomized government study found that on average, children continuously treated with stimulants grew three quarters of an inch less in height and gained 8.36 pounds less in weight than kids who took placebos. Moreover, children who ended treatment after 14 months continued to grow more slowly over the next 10 months than those continuously given placebo, suggesting that slowing may be irreversible.
By the time American boys reach high school, one in five is considered to suffer from ADHD. When 20 percent of a population has a problem, it’s time to look at the bigger picture.
Christopher Nystuen, MD, MBA