Baseline characteristics of European and non-European adult patients with attention deficit hyperactivity disorder participating in a placebo-controlled, randomized treatment study with atomoxetine

BACKGROUND: Attention deficit/hyperactivity disorder (ADHD) often presents as an impairing lifelong condition in adults; yet it is currently underdiagnosed and undertreated in many European countries. This analysis examines the characteristics of adult patients with ADHD in a European (EUR) and non-European (NE) patient population. METHODS: Baseline data from the open-label treatment period of a randomized trial of atomoxetine in adult patients with ADHD (N=2017; EUR, n=1217; NE, n=800) were examined. All patients who were enrolled were included in the baseline analyses. RESULTS: The demographics for patients in the EUR and NE groups were comparable. Patients in the EUR group had a somewhat lower percentage of prior exposure to psychostimulants compared with the NE group (32.7% vs. 38.9%, p=.0049). Scores on the Conners’ Adult ADHD Rating Scale-Investigator Rated: Screening Version with adult ADHD prompts (18-item total, inattentive and hyperactive/impulsive subscales, and index) were comparable. The adult ADHD Quality of Life-Life Outlook and Life Productivity domain scores were significantly different between groups (p≤.0004). The EuroQol-5 Dimension United Kingdom and United States population-based index scores and Health State score were comparable between groups. CONCLUSIONS: Adults with ADHD in Europe present similar demographics and baseline characteristics to those outside Europe and hence, study results outside Europe may be generalizable to patients in Europe. TRIAL REGISTRATION: Clinicaltrials.gov, NCT00700427