Comparison of cognitive flexibility and planning ability in patients with obsessive compulsive disorder, patients with obsessive compulsive personality disorder, and healthy controls

BACKGROUND Cognitive functioning in individuals with Obsessive Compulsive Disorder (OCD) and with Obsessive Compulsive Personality Disorder (OCPD) has not been adequately studied. AIM Examine the cognitive flexibility and planning ability of individuals with OCD and OCPD. METHODS Twenty patients with OCD and 25 patients with OCPD who had not taken medication in the previous two weeks were identified in an outpatient psychology clinic in Tehran, and 25 healthy control subjects were identified from the university staff and local community residents. All participants were administered the 28-item version of the General Health Questionnaire (GHQ-28), the Wisconsin Card Sorting Test (WCST), and the Tower of London (TOL) test. Two measures of the WCTS (number of perseverative errors and number of categories completed) were used to assess cognitive flexibility and three measures of the TOL (total number of moves in 12 trials, total response time, and planning time) were used to assess planning ability. RESULTS The level of current psychological distress in the two patient groups was significantly greater than that in the control group. After adjusting for demographic variables and the level of psychological distress, both OCD patients and OCPD patients made more perseverative errors on the WCST than control subjects, and the OCD patients (but not the OCPD patients) completed significantly fewer categories than the control subjects. Both the OCD patients and OCPD patients required significantly more moves than control subjects to complete the 12 TOL tasks and OCD patients took significantly longer than both OCPD patients and control subjects to complete the tasks. CONCLUSIONS Individuals with OCD and OCPD have impaired cognitive flexibility and planning ability compared to healthy controls, and there are some differences in these measures of cognitive functioning between OCD and OCPD. Long term follow-up studies of OCD and OCPD that assess changes in cognitive measures as the severity of obsessive compulsive symptoms wax and wane will be needed to determine whether or not such cognitive measures have diagnostic or clinical relevance for obsessive compulsive disorders.