ADHD spotlight: treatment adherence issues and effects of meds on adult height

- Jennifer Middleton, MD, MPH

The October 1 AFP included a useful review article on ADHD in children, and not long after I read it, I saw two more articles on ADHD that got me thinking even more about this subject: one on adherence to ADHD medication and one on the effect of psychostimulant medication on height.

The AFP article on "Diagnosis and Management of ADHD in Children" reviews the diagnostic criteria for ADHD, the differential diagnoses for common presenting complaints, and initial treatment options. The authors review the data for various treatments and conclude that psychostimulants are still the most effective class of medications for those children in whom meds are indicated.

A recent article published earlier this year in Patient Preference and Adherence reviewed how adolescent patient beliefs affected treatment adherence to ADHD medications. The author reviewed several studies, both qualitative and mixed-methods, that investigated adolescent attitudes toward their ADHD medications. Multiple studies found that the strongest predictors of non-adherence were either adverse medication effects, lack of perceived benefit, and/or "changes to the patient's sense of self." Teens with ADHD rated the perceived efficacy of medications higher than behavioral interventions, yet adolescents themselves are more likely to stop their medications on their own than to involve a parent in that decision.

Another recent article, this one from Pediatrics, seeks to lay to rest concerns about psychostimulant medications' effect on final adult height. The researchers obtained medication and growth histories from around 1000 children born between 1976-1982 in a town in Minnesota; for every 1 child identified with ADHD, they matched 2 control children without ADHD. The researchers obtained growth records on these children along with their final adult height, and they found no difference in growth patterns or final adult height between children with ADHD and children without ADHD; they also found no difference between children with ADHD on medication compared to children with ADHD who were not on medication. This study followed only one geographically-limited cohort, though, and the authors acknowledge the impossibility of knowing whether these children's physicians adjusted their medications due to changes in their growth curves. Despite these limitations, this study's years of longitudinal data are still compelling.

I spend significant time reviewing growth charts with parents of children or teens with ADHD on stimulant medication, but I don't ask questions about medication adherence the way I do, for example, with my patients with other chronic conditions. These two articles suggest that my priorities need reversing.

According to the AFP article, "children with ADHD [on a stimulant] are less likely to be held back a grade." Being held back a grade is definitely Patient-Oriented-Evidence-that-Matters! Since adolescents typically make the decision to stop their medication, centering discussions related to medication issues on them, instead of their parents, during office visits makes sense. And it is nice to be able to share with adolescents and their parents the recent Pediatrics study that was reassuring regarding possible height loss due to long-term stimulant use.

Certainly, as Dr. Lin wrote about earlier this year, medication is not always the right course for treating ADHD. But when it is, these two articles will change my practice. If you'd like to read more, there's an AFP By Topic on ADHD.

How do you counsel parents and their children and/or teens about ADHD treatment?