Combination of drug and behavior interventions are most effective for treating teenagers with ADHD
But larger doses not necessarily more effective and long-term effects not known
WASHINGTON — Ritalin and other stimulants have become the standard treatment for attention deficit hyperactivity disorder (ADHD) in elementary-age children because of their ability to curb disruptive and defiant behavior and allow children to focus. Now, a new study appearing in the current issue of Experimental and Clinical Psychopharmacology, published by the American Psychological Association (APA) finds that Ritalin also improves daily academic performance and behavior of teenagers.
In the first empirical study of its kind, researchers Steven W. Evans, Ph.D., and colleagues William E. Pelham Jr., Ph.D., and Bradley H. Smith, Ph.D., found that methylphenidate (MPH)--the drug best known by the trade name Ritalin -- in combination with a behavior modification intervention, improved adolescent’s diagnosed with ADHD performance on a range of academic measures, including note-taking, daily assignments and quiz scores, without causing major side effects.
"When they were taking stimulant medication, students were more likely not only to get schoolwork done, but to get it done more accurately than when they were taking a placebo," says Dr. Evans. "Scores improved by an average of about 17 percent--a jump that could mean two or three letter grades."
Most research on ADHD has focused on behavioral problems, such as disruptive or defiant behavior. But because problems in school are one of the hallmarks of ADHD in adolescents, Evans and his colleagues measured the effects of different doses of MPH not only on teenagers' behavior, but also on their academic performance. With a grant from the National Institute of Mental Health, they examined 45 adolescents diagnosed with ADHD and enrolled in a University of Pittsburgh intensive summer treatment program, directed by Pelham, for youth with ADHD. Because ADHD affects boys more often than girls, most of the study participants were male.
Three times per day during the eight-week study, the researchers gave participants either a placebo or a 10-, 20- or 30-milligram dose of MPH (each day's third dose was half the size of the first and second dose). The students received each dose of the drug, or a placebo, for one day each week, in random order, allowing the researchers to compare their behavior and academic performance in each of the drug conditions.
In addition to attending a one-hour history class four days a week, all students participated in other structured activities, such as note-taking instruction and social skills and problem solving groups, designed to help them learn to control their behavior. The researchers measured the quality of students' note-taking, their performance on daily quizzes, in-class worksheets and writing assignments, and how often they completed homework assignments. Evans' team also observed how often students displayed disruptive, inattentive or defiant behavior in the classroom.
Results showed that MPH, when administered as part of the intensive behavior change interventions significantly boosted the quality of students' schoolwork. About 80 percent of adolescents showed improved academic performance while taking some dose of stimulant medication.
The research also revealed important individual differences in adolescents' response to the drug and that increasing the dosage did not necessarily improve student performance. Two-thirds of teen-agers in the study showed moderate to large improvement in academic performance while on 10 milligrams of MPH, compared with placebo. Of those who did not improve significantly on the lowest dose, fewer than half showed substantial improvement when the dose was increased to 20 milligrams, and very few students achieved significant gains on a 30-milligram dose of the drug. In fact, some students' performance deteriorated when their dosages of MPH increased.
"That's extremely important," stresses Pelham. "There are lots of psychiatrists out there who believe that if you keep upping the dose, people will continue to get better." The fact that that wasn't the case, he explains, is important because "you want the total amount of psychoactive drugs that a person takes in his or her lifetime to be as low as possible, because we don't know what the long-term effects are."
"There would be a lot less controversy about medication for ADHD if people were consistently implementing both medication and evidence-based behavioral interventions, " suggests Evans. He and his colleagues found the lack of research on ADHD treatment for adolescents disturbing because, as scientists are increasingly recognizing, the disorder continues far beyond childhood. "When children hit puberty," Evans observes, "they go through a lot of changes--hormonally, cognitively, emotionally and interpersonally. So there are lots of reasons why interventions that are effective in younger children may or may not be effective later." The authors caution that their study doesn't indicate whether taking stimulant medications helps students' school performance over the long term. Indeed, because it's not practical--or indeed ethical--to conduct long-term studies in which researchers randomly assign participants to different doses of stimulant medication or a placebo--and because many young people stop taking medication during adolescence--that question is particularly difficult to answer, they note.
Article: "Dose-Response Effects of Methylphenidate on Ecologically Valid Measures of Academic Performance and Classroom Behavior in Adolescents with ADHD," Steven W. Evans, Ph.D., James Madison University; William E. Pelham, Ph.D., and Elizabeth M. Gnagy, Ph.D., State University of New York at Buffalo; Bradley H. Smith, Ph.D., University of South Carolina; Oscar Bukstein, Ph.D., Andrew R. Greiner, Ph.D., Lori Altenderfer, Ph.D., and Carrie Baron-Myak, Ph.D., University of Pittsburgh Medical Center; Experimental and Clinical Psychopharmacology, Vol 9, No. 2.
Steven W. Evans, PhD can be reached by telephone at (540) 568-2538 or by email at email@example.com
William E. Pelham, PhD can be reached by telephone at (716) 829-2244 ext 29 or ext 31 or by email at firstname.lastname@example.org
The American Psychological Association (APA), in Washington, DC, is the largest scientific and professional organization representing psychology in the United States and is the world’s largest association of psychologists. APA’s membership includes more than 155,000 researchers, educators, clinicians, consultants and students. Through its divisions in 53 subfields of psychology and affiliations with 60 state, territorial and Canadian provincial associations, APA works to advance psychology as a science, as a profession and as a means of promoting human welfare.