Impaired executive functions in paediatric obsessive-compulsive disorder patients

Isik Taner Y, Erdogan Bakar E, Oner O. Impaired executive functions in paediatric obsessive-compulsive disorder patients. Objective: There are only few studies which investigated the neuropsychological performances of paediatric patients with obsessive-compulsive disorder (OCD). Previous studies show that most of adult OCD patients had an onset of their first symptoms before the age of 15. Our objective was to evaluate the neuropsychological functions in paediatric patients with OCD. Methods: We compared the executive functions and general intelligence of child and adolescent OCD patients (n = 20) with age- and gender-matched healthy controls (n = 20). To compare mentioned skills, a neuropsychological test battery including Wechsler Intelligence Scale for Children-Revised (WISC-R), Wisconsin Card Sorting Test (WCST), Stroop Test and Verbal Fluency Test was performed. Result: Performances of the OCD and control subjects on neuropsychological tests were statistically analysed by using multivariate analysis of covariance (MANCOVA), in which Full Scale Intelligence Quotient (FSIQ) results were taken into consideration as a covariate to observe FSIQ's effect on test scores. Our results showed that the differences in WISC-R Picture Arrangement and Coding scores remained significant when co-analysed with FSIQ scores. In a similar manner, the OCD group exhibited worse performances on STR1-duration, STR3-duration, STR3-error, STR4-duration, STR4-error, STR5-correct response, and STR5-error as compared with the control group when FSIQ scores were taken into calculation. Some variables of the WCST (perseverative responses, percent errors, abstraction-flexibility and categories completed) also yield lower test scores in the OCD group. There was no significant difference between the groups regarding Verbal Fluency Test scores. Conclusion: Our results suggested that paediatric OCD patients had worse abstraction-flexibility, mental set-shifting, verbal comprehension and visuospatial/construction abilities.