Efficacy and Safety of Methylphenidate and Atomoxetine in Medication-Naive Children with Attention-Deficit Hyperactivity Disorder in a Real-World Setting.

Background and objective: Methylphenidate (MPH) and atomoxetine (ATX) are the most common medications used to treat attention-deficit hyperactivity disorder (ADHD) in China; however, despite this, there is still a paucity of studies comparing their efficacy and safety, particularly for different characteristics. To address the lack of research, a real-world prospective cohort study was conducted to examine these properties of MPH and ATX, and to analyze correlations associated with age, sex, and different ADHD presentation.

Methods: Children with ADHD meeting the eligibility criteria were recruited from January 2016 to July 2021. Study participants were treated with either MPH or ATX prescribed in the real-world setting, and were followed up for 26 weeks. Clinical efficacy response and adverse events (AEs) were recorded and measured. Subgroup analysis was performed to examine the efficacy response and AEs associated with age, sex, and different ADHD presentation.

Results: A total of 1050 children were recruited and 29 children were lost to follow-up. Of the 1021 children remaining, 533 were treated with MPH and 488 were treated with ATX. No significant differences were found in intelligence quotient, age, sex, or ADHD presentation between the MPH- and ATX-treated groups (p > 0.05). The response rates were 84.6% in the MPH-treated group and 63.3% in the ATX-treated group. Subgroup analysis of response rate demonstrated that the treatment effect of MPH over ATX was consistent across subgroups except in the girls (odds ratio [OR] 2.09, 95% confidence interval [CI] 0.97-4.7) and the hyperactive/impulsive presentation group (OR 2.88, 95% CI 0.77-12.76). A total of 47.8% of children experienced AEs during MPH treatment, significantly lower than the rate of 56.8% during ATX treatment (p < 0.05). The incidence of AEs in the MPH-treated group was higher in young children (<8 years: 56.8%; 8-10 years: 47.2%) and lower in children over 10 years of age (29.0%).

Conclusions: Overall, MPH was more effective and better tolerated than ATX. The incidence of AEs in children treated with MPH varied with age, and was higher in young children and lower in children over 10 years of age.