Extended-release methylphenidate (Concerta) had no effect on learning academic material taught in a small group of children with attention-deficit/hyperactivity disorder (ADHD), a controlled crossover study found.
As in previous studies, however, the stimulant did improve seat work productivity and classroom behavior, but these benefits did not translate into better learning of individual academic learning units, according to William E. Pelham Jr., PhD, of the department of psychology at Florida International University in Miami, and colleagues.
The results were published online in the Journal of Consulting and Clinical Psychology.
Dr. William E. Pelham Jr.
The authors said the finding raises questions about how stimulant medication leads to improved academic achievement over time. “This is important given that many parents and pediatricians believe that medication will improve academic achievement; parents are more likely to pursue medication (vs. other treatment options) when they identify academic achievement as a primary goal for treatment. The current findings suggest this emphasis may be misguided,” they wrote.
In their view, efforts to improve learning in children with ADHD should focus on delivering effective academic instruction and support such as individualized educational plans rather than stimulant therapy.
The study
The study cohort consisted of 173 children aged 7-12 (77% male, 86% Hispanic) who met Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria for ADHD and were participating in a therapeutic summer camp classroom.
The experimental design was a triple-masked, within-subject, AB/BA crossover trial. Children completed two consecutive phases of daily, 25-minute instruction in both subject-area content (science and social studies) and vocabulary. Each phase was a standard instructional unit lasting for 3 weeks and lessons were given by credentialed teachers via small-group, evidence-based instruction.
Each child was randomized to receive daily osmotic-release oral system methylphenidate (OROS-MPH) during either the first or second instructional phase and to receive placebo during the other.
Seat work referred to the amount of work a pupil completed in a fixed duration of independent work time, and classroom behavior referred to the frequency of violating classroom rules. Learning was measured by tests, and multilevel models were fit separately to the subject and vocabulary test scores, with four observations per child: pretest and posttest in the two academic subject areas.
The results showed that medication had large, salutary, statistically significant effects on children’s academic seat work productivity and classroom behavior on every single day of the instructional period.
Pupils completed 37% more arithmetic problems per minute when taking OROS-MPH and committed 53% fewer rule violations per hour. In terms of learning the material taught during instruction, however, tests showed that children learned the same amount of subject-area and vocabulary content whether they were taking OROS-MPH or placebo during the instructional period.
Consistent with previous studies, medication slightly helped to improve test scores when taken on the day of a test, but not enough to boost most children’s grades. For example, medication helped children increase on average 1.7 percentage points out of 100 on science and social studies tests.
“This finding has relevance for parents deciding whether to medicate their child for occasions such as a psychoeducational evaluation or high-stakes academic testing – while the effect size was small, findings suggest being medicated would improve scores,” the investigators wrote.
Sharing his perspective on the study but not involved in it, Herschel R. Lessin, MD, a pediatrician at The Children’s Medical Group in Poughkeepsie, N.Y., and coauthor of the American Academy of Pediatrics (AAP) guidelines on ADHD, said, “If you ignore the sensationalized headlines, this study is an interesting but preliminary first step, and justifies further research on the topic. It also has several potential defects, which the authors in fact address in the supplements.” The cohort size was small, for example, the doses of medication were very low, and the study took place in a controlled therapeutic setting – not the everyday classroom.
Dr. Herschel R. Lessin
Furthermore, Dr. Lessin added, the study’s conclusions “are contrary to my 40 years of experience in treating ADHD. If they had used standard measures of assessment, as in previous studies, they would have found medication did impact learning. More research is clearly needed.”
In other comments, Holly K. Harris, MD, assistant professor of pediatrics-development at Baylor College of Medicine and Texas Children’s Hospital in Houston, said the core symptoms of ADHD are primarily behavioral in nature, not academic learning related.
Dr. Holly K. Harris
“Stimulant medications are targeting these core behavioral symptoms of ADHD ... but the goal of treatment is more than just the reduction of symptoms; it is to improve a child’s overall functioning so that they succeed at what is expected of them and avoid developing even more impairments,” Dr. Harris said, adding that symptom improvement can sometimes allow a child to learn better in the classroom and achieve more academically.
Children with ADHD may have diagnosed or undiagnosed comorbid learning disabilities, with one 2013 study suggesting a rate of 31%-45%.
With such learning disabilities being distinct from core behavioral symptoms, stimulant medications would not be expected to address a child’s learning disability. “In fact, best practice is for a child with ADHD who is not responding to stimulant medication (doctors might refer to this as complex ADHD) to undergo full individual evaluations either through the school system or an outside psychological assessment to assess for potential learning disabilities or other comorbid developmental/learning or psychiatric diagnosis,” Dr. Harris said.
Rather than changing prescribing patterns, she continued, pediatricians could consider advising parents to request learning evaluations through the school system if the child continues to struggle academically with no change in learning outcomes despite improvement in some behavioral outcomes.
As a reference, Dr. Harris recommended the Society for Developmental and Behavioral Pediatrics guidelines for complex ADHD.
This study was funded by the National Institute on Mental Health with additional support from the National Institute on Alcohol Abuse and Alcoholism, the National Institute on Drug Abuse, and the Institute of Education Sciences. Coauthor James Waxmonsky, MD, has received research funding from the National Institutes of Health, Supernus, and Pfizer and served on the advisory board for Iron Shore, NLS Pharma, and Purdue Pharma.