Attention Deficit Hyperactivity Disorder (ADHD)presents high levels of life-long comorbidity. Several studies demonstrate an elevated coocurrence between ADHD and Substance Use Disorder (SUD) as well as personality disorders.

The objective of this poster is to demonstrate differential characteristics between ADHD with SUD patients versus ADHD without SUD, in relation to Axis II comorbidity, ADHD symptoms severity and childhood behavioural disorders (conduct disorder and oppositional defiant disorder).

Another objective is to identify differences in the prevalence of SUD relative to gender and ADHD subtype (Inattentive, Hyperactive/Impulsive and Combined).

This will be done using a comparative-descriptive study that was carried out with a sample of 125 adults diagnosed with ADHD using the CAADID in the Adult ADHD Integral Programme (PIDAA) of Vall d'Hebron Universitari Hospital; 53 subjects presented associated SUD (DSM-IV). All the subjects were evaluated with ADHD Rating Scale, SCID-I, SCID-II and K-SADS.

Relative to ADHD group, subjects ADHD with SUD subjects showed higher comorbidity with Axis–II Disorders, especially with antisocial, schizoid and paranoid personality disorders, as well as major prevalence of conductual disorder and oppositional defiant disorder in childhood. There were no significant differences respect to ADHD symptoms severity nor ADHD subtype between both groups. A major proportion of men were observed in ADHD with SUD group compared to ADHD patients.