Long-term outcomes of childhood ADHD stimulant use trajectories

Stimulant medication is the first-line pharmacological treatment option for children with attention-deficit/hyperactivity disorder (ADHD). However, long-term effects remain unclear. Therefore, we explored long-term (>12 years) outcomes of childhood stimulant medication use, using data from the Dutch NeuroIMAGE cohort. Childhood (up to M_age=16.14, SD_age=3.48) stimulant treatment trajectories were detected using K-means clustering based on age at initiation, stop age, total and maximum daily dose, and duration and variability of stimulant use in 324 children. The trajectories were compared across seven domains of adult outcomes (controlling for multiple testing) including psychiatric status, behavioral and emotional functioning, academic and professional functioning, adaptive functioning, neurocognitive functioning, physical health, and healthcare service use. At follow-up, 143 adults with childhood ADHD (M_age=28.34, SD_age=3.74, 65% males) were part of three stimulant treatment trajectory groups: early-and-intense (n = 46), late-and-moderate (n = 63), and stimulant-naïve (n = 34). The three groups did not differ on any of the 51 adult outcomes and findings did not change after controlling for age and sex, except that a significant group difference emerged for callous and unemotional traits (behavioral and emotional functioning domain). More specifically, the early-and-intense and late-and-moderate groups had more favorable scores compared to stimulant-naïve group, although this may partly reflect pre-existing group differences. The main findings did not change after controlling for ADHD medication use at wave IV. Overall, stimulant medication use in childhood did not predict long-term outcomes in those with childhood ADHD in our sample, suggesting that there may be no lasting effects of stimulants on many long-term functional outcomes.