Unaltered dopamine transporter availability in adult attention deficit hyperactivity disorder

Objective: The authors examined whether patients with attention deficit hyperactivity disorder (ADHD) have altered striataldopamine transporter levels, which may explain psychostimulant effects in this disorder. Method: Single photon emission computed tomography and [I-123]2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ([I-123]beta-CIT) were used to assess dopamine transporter availability in nine adult patients with ADHD (eight of whom were stimulant naive) and nine age- and gender-matched healthy comparison subjects. Results: Striatal [I-123]beta-CIT binding did not differ significantly between the ADHD and comparison subjects. Conclusions: The findings suggest that a hypothesized dysregulation of dopamine function in ADHD does not entail altered dopamine transporter levels.