Neuropsychological functions as trait markers in OCD: A 10-year follow-up study.

BACKGROUND

The alterations in neuropsychological performance described in Obsessive-Compulsive Disorder (OCD) reflect dysfunctions of the neurobiological structures underlying the disorder. Cognitive functions are influenced by clinical variables and are considered a potential endophenotype of the disorder. Although OCD is a chronic illness, data regarding the course of cognitive impairment are scarce.

METHODS

The present study assessed 60 OCD patients and 30 healthy controls (HC). Both groups were followed for a period of 10.6 years (range 5-18 years). Neuropsychological performance was assessed with a battery measuring executive subcomponents and non-verbal memory at baseline and after follow-up, using repeated-measures mixed models. Several clinical variables were also assessed in the patient group.

RESULTS

At baseline, patients with OCD demonstrated significantly poorer performance on neuropsychological tests than HC. Overall, the patterns of specific executive processes (organizational strategies and working memory) and non-verbal memory remained unchanged during the follow-up period in both groups. A reduction in severity of depression and obsessive-compulsive symptomatology was observed at the end of follow-up in OCD patients. In the sample, female sex was associated with worse performance on certain executive functions, and age with greater impairment in non-verbal memory after a decade of follow-up.

CONCLUSIONS

OCD patients showed significant impairments on neuropsychological tests compared to HC at baseline. After follow-up, both groups showed a similar decline in neuropsychological performance, with no significant differences. These findings suggest that cognitive deficits in OCD remain stable over time and may reflect trait-like characteristics, and that sex may differentially affect cognitive performance with aging.