Atomoxetine treatment for pediatric patients with attention-deficit/hyperactivity disorder with comorbid anxiety disorder.

Objective: Research suggests 25% to 35% of children with attention-deficit/hyperactivity disorder (ADHD) have comorbid anxiety disorders. This double-blind study compared atomoxetine with placebo for treating pediatric ADHD with comorbid anxiety, as measured by the ADHD Rating Scale-IV-Parent Version: Investigator Administered and Scored (ADHDRS-IV-PI) and the Pediatric Anxiety Rating Scale (PARS).

Method: Patients (ages 8-17 years) meeting DSM-IV criteria for ADHD and generalized anxiety disorder, separation anxiety disorder, and/or social phobia were randomized to 12 weeks of atomoxetine (n = 87) or placebo (n = 89). ADHDRS-IV-PI and PARS total scores were analyzed using analysis of covariance last observation carried forward and repeated-measures analyses.

Results: Sixty-six patients in each group completed the study. Mean ADHDRS-IV-PI total score improved significantly for atomoxetine (n = 55; -10.5, SD 10.6) relative to placebo (n = 58; -1.4, SD 8.3; p < .001). Mean PARS total score also improved significantly for atomoxetine (n = 55; -5.5, SD 4.8) relative to placebo (n = 58; -3.2, SD 5.0; p = .011).

Conclusions: Atomoxetine was efficacious in reducing ADHD symptoms in patients who have ADHD with comorbid anxiety and was well tolerated. There was also a significant reduction in independently assessed anxiety symptoms using both clinician-rated and self-rated measures, which merits further investigation. Results support consideration of atomoxetine for the treatment of ADHD in youths who have ADHD with comorbid anxiety disorder.

Clinical Trial Registration Information: The LYBP study, on which this article is based, was not registered at clinicaltrials.gov because the last patient visit occurred before July 1, 2005. Results, however, are publicly posted at lillytrials.com and clinicalstudyresults.org. The unique study ID at both sites is 6477a.