• obsessive–compulsive disorder;
  • impulsiveness;
  • cognitive impulsiveness;
  • neuropsychological disinhibition

Objective:  Although obsessive–compulsive disorder (OCD) is usually conceptualized as an anxiety disorder some studies suggested it to be a deficit of impulse control. The purpose of this study was to assess impulsiveness in OCD families and compare it to control families.

Method:  Seventy cases and their 139 relatives were compared with 70 controls and their 134 relatives from a German family study on OCD (German Epidemiologic Network for OCD Studies). All subjects were interviewed and diagnosed according DSM-IV criteria and were administered the Barratt Impulsiveness Scale (BIS) and PADUA-Inventory to assess obsessive-compulsive symptoms.

Results:  OCD subjects had significantly higher scores of cognitive impulsiveness. However, first-degree relatives of OCD cases and of controls had comparable BIS-11 scores. Significant associations of aggressive obsessions and checking with cognitive impulsiveness were found.

Conclusion:  OCD is a severe mental disorder that is characterized by a lack of cognitive inhibition. However, impulsiveness does not represent a familial trait in families of OCD subjects.