Morning and evening behavior in children and adolescents treated with atomoxetine once daily for Attention-Deficit/Hyperactivity Disorder (ADHD): Findings from two 24-week, open-label studies

Background The impact of once daily atomoxetine treatment on symptoms in children and adolescents with ADHD may vary over the day. In order to capture such variations, two studies were undertaken in children and adolescents with ADHD using two instruments that capture morning and evening behavior and ADHD-related difficulties over the day. This secondary measure analysis builds on two primary analyses that were conducted separately for children and adolescents and also published separately.Methods In two open-label studies, ADHD patients aged 6-17 years (n = 421), received atomoxetine in the morning (target-dose 0.5-1.2 mg/kg/day) for up to 24 weeks. Morning and evening behavior was assessed using the investigator-rated Weekly Rating of Evening and Morning Behavior (WREMB-R) scale. ADHD-related difficulties at various times of the day (morning, during school, during homework, evening) were assessed using the Global Impression of Perceived Difficulties (GIPD) scale, rated by patients, parents and physicians. Data from both studies were combined for this secondary measure analysis.Results Both WREMB-R subscores decreased significantly over time, the evening subscore from 13.7 (95% CI 13.2;14.2) at baseline to 8.0 (7.4;8.5) at week 2, the morning subscore from 4.3 (4.0;4.5) to 2.4 (2.2;2.6). Scores then remained stable until week 24. All GIPD items improved correspondingly. At all times of the day, patients rated ADHD-related difficulties as less severe than parents and physicians.Conclusion These findings from two open-label studies suggest that morning and evening behavior and ADHD-related difficulties in the mornings and evenings improve over time with once daily atomoxetine treatment.