Impaired Wisconsin Card Sorting Test performance in first-episode severe depression

An important issue in the practice of clinical neuropsychology is to define the degree to which impaired executive functions associated with severe depression are a result of organic dysfunction or of only current depressive experience, reflecting clinical state. Twenty-eight patients with psychotic depression, 29 with nonpsychotic depression and 30 healthy controls, matched for age and education were tested on WCST, WAIS-R, and the Rorschach according to the Comprehensive System, providing indices of depression (DEPI) and coping deficit (CDI). Patients were impaired in WCST performance. The stepwise regression for WCST scores yielded two significant predictor variables: the DEPI and Digit Symbol as a measure of complex attention and response speed. Within the groups, Picture Completion in patients with nonpsychotic depression and the CDI in patients with psychotic depression emerged as the significant predictors of WCST scores. Patients with severe major depressive disorder have profound executive impairments as assessed by the WCST at early stages of the illness. Intense emotional distress and psychomotor retardation seem to contribute to impaired performance. The depression groups revealed different response patterns, reflecting more severe deterioration and signs of possible organic dysfunction in patients with psychotic depression.