Journal of International Psychiatry

Objective To explore risperidone monotherapy treatment effect on cognitive function and clinical symptoms, and the correlation between cognitive function and clinical symptoms in treatment-naïve first-episode schizophrenia patients. Methods Forty-two treatment-naïve patients with first-episode schizophrenia were assessed with Wisconsin Card Sorting Test (WCST), Digit Span Distraction Test (DSDT), Verbal Fluency Test (VFT), Stroop Color Word Test, Trail Marking Test (TMT) to explore their executive function, working memory and information processing speed at baseline and then after 8 weeks of risperidone monotherapy. Positive and Negative Syndrome Scale (PANSS) was used to evaluate patients’ clinical symptoms. Multiple regression analysis was utilized to compute the relation between cognitive deficits and symptoms. Results At baseline, WCST_perseverative errors of patients were significantly more than healthy volunteers (P<0.001), and the number of WCST_categories, DSDT_forward / backward and VFT was significantly less than control group (Ps<0.01). The time consumed in Stroop and TMT of patients was significantly more than that of volunteers (Ps<0.001). After treatment, patients’ time consumed in Stroop_B and Stroop_C was significantly less than that at baseline, but there were no significant within-group differences in other cognitive performance. The worse of the performance in TMT_A/B, the more severe of patients’ negative and total symptoms (Ps<0.05). The worse performance of the TMT_A at baseline, the less improvement of patients’ positive symptoms (P=0.019). Conclusions Patients already have suffered from extensive cognitive impairments in their early episode. Patients’ psychotic symptoms and information processing deficits can be improved after therapy in acute stage, although their executive function and working memory are not improved. These imply that biological mechanisms underlying information processing deficits in patients with first-episode may be state-biomarkers, but executive function and working memory impairments may be trait-biomarkers.

Schizophrenia; Risperidone; Cognitive function