Main features of antisocial personality disorder (APD) are aggression, tendency to violence, poor frustration tolerance, impulsivity, difficulties in learning from experiences. Attention deficit hyperactivity disorder (ADHD) is characterized with difficulty to sustain attention, hyperactivity and impulsivity. Association between ADHD and violent behavior is well known. Childhood onset ADHD carries a high risk of persisting into adulthood as antisocial behaviors.

In the present study, comorbidity of adult ADHD was screened in a group of patients with APD. Executive functions and attention were assessed by using neuropsychological test instruments. In addition, their relation to ADHD subtypes was investigated.

A total of 90 male subjects with APD were included. Also, 90 age- and sex-matched healthy control subjects were involved into the study. The patients and control subjects were assessed by a semi-structured socio-demographic form, SCID-II, Turgay's Adult ADHD Rating Scale, Wender Utah Rating Scale, Wisconsin Card Sorting Test, Stroop Test, Continuous Performance Test, and Trail-Making Test.

Comorbidity rate of adult ADHD was 83.3% in APD group while 6.7% of control subjects had a diagnosis of adult ADHD. The most frequently diagnosed ADHD subgroup was combined type in both APD and control group. In APD group, executive functions were significantly more deficient as compared to the control group. Among all ADHD subgroups, inattention subtype had the worst performance in neuropsychological assessments.

Comorbidity of adult ADHD was quite common in APD subjects. Executive functions were generally deficient in APD patients with a co-diagnosis of adult ADHD.