RESUMEN
Some evidence points to an increased rate of cluster B and C personality disorders (PDs) in adult ADHD patients. In order to assess axis II disorders comprehensively we used the diagnostic instrument of the WHO. In sixty adult out-patients with ADHD according to DSM-IV criteria PDs were assessed with the International PD Examination (IPDE) and severity of childhood ADHD with the Wender-Utah-Rating Scale (WURS). We found at least one PD in 25% of cases. Cluster C PDs were most common (36.6%) followed by Cluster B (23.3%) and A (8.3%). Avoidant (21.7%) and borderline (18.3%) were the most frequent single PD entities. ADHD patients with PD suffered from significantly more severe childhood ADHD compared to those without co-occurring PD. Applying the IPDE we confirmed a high number of PDs among adult ADHD patients. Our findings point to a higher vulnerability for the development of PDs in patients with severe childhood ADHD.