In a much-anticipated, five-year follow-up study of one of the largest samples of girls with ADHD ever examined, UC Berkeley researchers found not only that difficulties for girls suffering from the disorder persist during their teens, but that insidious new problems can emerge. These findings are published in the June 2006 issue of the Journal of Consulting and Clinical Psychology. The results, health professionals say, should help dispel ideas that the disorder, which affects an estimated 4.4 million American children, poses less of a risk to girls than to boys, on whom most research has focused.

"As girls with ADHD mature into adolescence, on average they don't show as many visible symptoms of the condition, especially the most noticeable form - hyperactive behavior," said the study's lead author, Stephen Hinshaw, who is a UC Berkeley professor of psychology and chair of the psychology department.

"But we can't get fooled into thinking things are fine. Delinquent and depressed behaviors, risk for substance abuse, symptoms of eating disorders, high need for services, difficulties with peers - these problems hit girls with ADHD harder than they did for the comparison group without the condition," he added.

Since 1997, Hinshaw and his team have tracked a racially and socio-economically diverse group of girls with ADHD through summer camps and into adolescence, comparing them with girls who did not meet the criteria for ADHD but were otherwise demographically matched.

The childhood study, funded by a grant from the National Institute of Mental Health (NIMH), included a sample of 140 girls with ADHD and 88 without the disorder. The girls were aged six to 12 and were an ethnically and economically diverse group of girls: Slightly more than half were white, 27 percent were black, 11 percent were Latina and 9 percent were Asian American.  Together, they attended five-week camps where they were closely monitored by the staff as they partook in art and drama classes and outdoor activities. Those taking ADHD medication volunteered to go off the drug treatment for much of the summer camp study. The counselors and staff observing all 228 girls and monitoring their interactions did not know which of them had been diagnosed with ADHD. Observations by the staff were augmented by testing, interviews and other assessments.

Published in 2002 in the Journal of Consulting and Clinical Psychology, the first study of these girls found that the ADHD group had more problems making and keeping friends, and functioning outside school; the girls also lagged behind their peers academically.  Results also suggested that girls are underdiagnosed for the disorder because they are more prone to "inattentive-type" ADHD, which is marked by disorganized and unfocused behavior rather than the disruptive, impulsive conduct seen in boys..
 
How, Hinshaw and his team wondered, would they fare after five years? To answer that question, researchers reassessed 92 percent of the group who agreed to cooperate and had dispersed to eight states as well as South Korea and Australia. Researchers conducted eight-hour assessments of each girl.

Some in the ADHD group had received no treatment during the intervening five years, while others received extensive help. About 50 percent, Hinshaw said, had taken medication at some point and 80 percent were receiving special services, mostly in school. Some had made significant recoveries and no longer had ADHD, but most continued to struggle.

Five years later, researchers conducted a follow-up study involving 209 of the girls, who had entered middle and high school. In nearly a dozen areas examined by researchers -- including academic performance, prevalence of eating disorders, relationships with peers and teachers, and organizational skills -- the girls with ADHD were significantly more likely to have problems than those in a matched control group who did not have the disorder. Although the fidgety, impulsive symptoms exhibited during childhood had subsided in many cases, the gap in reading and math ability had widened in five years and new concerns had emerged: About 30 percent of the girls with ADHD were at least mildly depressed, compared with 10 percent of the control group, Hinshaw said. The same percentages were seen in substance abuse. Moreover, in many cases, risky behaviors had surfaced. One area showed marked improvement: The girls in the ADHD group showed fewer signs of hyperactivity as they grew older, the same trend seen among boys in other studies.

"Girls with ADHD have impairments that are not transitory but that persist through adolescence. And they are persisting in areas of function that are really crucial for success in adulthood," Hinshaw said. "They're behind academically and socially. Even if symptoms improve, underlying deficits seem chronic, and we need to do a lot more for early intervention."  

Pelham called Hinshaw's results "very important" because so little is known about teenage girls with ADHD. Too often, he said, the problem is either overlooked or misdiagnosed as depression.

To Washington area developmental pediatrician Patricia Quinn, who has specialized in the treatment of ADHD for nearly 30 years, the results of Hinshaw's study serve as a warning.

"People think if a girl is ditzy she's not going to have serious problems, but this study confirms that's not true," said Quinn, who has co-authored books about girls and women with ADHD.

Molly Zametkin, 18, a recent high school graduate from Kensington, Md., knows firsthand that girls can be as affected as boys, even if their problems seem less obvious.

First diagnosed in elementary school, Zametkin, who described herself as "a little space cadet who was never hyperactive," vehemently fought her parents' efforts to treat ADHD with medication and therapy. Her father is a research psychiatrist at the National Institute of Mental Health.

Only after years of struggling in school, Zametkin said, did she accept that "it was a problem I couldn't fix by myself"; she began taking medication regularly when she started high school.

The Berkeley findings, she said, mirror aspects of her experience as well as what she sees in other girls who have ADHD, especially their battles with food and their use of drugs, alcohol and cigarettes.

"Any girl with ADHD is going to be more impulsive and more of a risk-taker," Zametkin said. "And impulsivity makes it easier to give in to peer pressure in any situation."

For parents coping with difficult teenage ADHD behavior, Hinshaw warned, adolescence can be tricky as they try to strike a balance between encouraging their daughters to stick to their treatment regimen -which may involve medication, family therapy, school supports, or a combination - while supporting their need for autonomy.

"At the very time adolescence is occurring for these kids, demands for independence are increasing exponentially," he said.

Hinshaw said he hopes these new findings will underscore the need for long-lasting professional intervention for children with ADHD and convince families struggling with the disorder that it's a misconception that ADHD is not a "real" condition - and that diagnosis and treatment are crucial.
His research team has won a new NIMH grant for a 10-year follow-up study of the same girls. It is set to begin later this year.

"Can you believe it's 2006" and the first long-term prospective study of girls with ADHD is just being published, asked psychologist William Pelham at the State University of New York at Buffalo.