BACKGROUND AND AIM:

Dopamine transporters are the target of psychostimulants used for treatment of attention-deficit/hyperactivity disorder (ADHD). Therefore, the present study aimed to evaluate striatal dopamine transporter density in adult patients with ADHD.

METHODS:

Twenty patients (11 female, nine male; mean age 35+/-7 years) and 20 control subjects (11 female, nine male, mean age 32 +/- 8 years) were examined with SPECT using the specific radiotracer 123I-FP-CIT. The ratio of striatal to cortical radioactivity concentration was used for semiquantitative evaluation of dopamine transporter binding potential (V3''). There was a significant influence of age (P < 0.001) and a trend towards an influence of gender (P = 0.053) on V3''. An ANCOVA with these covariates showed a slightly higher V3'' in the patients than in the control subjects (4.24 +/- 0.48 vs. 4.03 +/- 0.56; P = 0.02).

CONCLUSION:

This study provides further in-vivo evidence for an involvement of the dopamine transporter in ADHD. However, compared to previous studies, the increase of dopamine transporter density in the patient group is less pronounced here.