Response to methylphenidate in children and adolescents with ADHD: does comorbid anxiety disorders matters?

There are controversial evidence in the literature on the role of comorbid anxiety disorders (ANX) in the improvement of attention-deficit/hyperactivity disorder (ADHD) symptoms with methylphenidate (MPH) treatment. Our main objective was to assess differences in the response to MPH treatment in children and adolescents with ADHD with and without comorbid ANX. We extensively evaluated response to MPH in a naturalistic study of 280 children and adolescent with ADHD according to DSM-IV criteria. Psychiatric diagnoses (ADHD, ANX, and other comorbidities) were assessed by semi-structured interviews (K-SADS-E). Response to MPH was assessed by means of total score in the Swanson, Nolan, and Pelham Scale-version IV (SNAP-IV) after 1 month of treatment. There was no significant between-group difference in the response to treatment with MPH after 1 month either when SNAP-IV scores were assessed dimensionally or categorically (moderate response) (P > 0.05). Our findings suggest that comorbid ANX do not interfere in the response to MPH on core ADHD symptoms.