Aim was to evaluate influencing factors of response and symptomatic remission in first-episode schizophrenia patients treated with risperidone or haloperidol.

229 first-episode schizophrenic patients were examined within a double blind controlled trial of the German Study Group on first-episode schizophrenia with biweekly PANSS ratings. Response was defined according to the definition by Lieberman et al. (2003) and symptomatic remission as the severity component of the consensus remission criteria by the Remission in Schizophrenia Working Group. Sociodemographic, psychopathological and functional variables as well as the treatment applied were evaluated regarding their potential predictive validity for treatment outcome. Univariate tests, logistic regression and CART-analyses were consulted as statistical methods.

126 patients (55%) achieved response and 118 patients (52%) symptomatic remission at discharge with no significant differences between the risperidone (51%) and haloperidol (49%) treated patients. Better baseline functioning, early treatment response, less depressive symptoms and a shorter duration of untreated psychosis were revealed significant predictors of response. Patients with symptomatic remission also had a significantly shorter duration of untreated psychosis and significantly less depressive symptoms at baseline. Logistic regression and CART-analyses revealed low general psychopathology, early treatment response and a high score in the Strauss-Carpenter-Prognostic-Scale at admission to be significantly positive predictive for symptomatic resolution.

Early treatment response, depressive symptoms and the level of psychosocial functioning were revealed to significantly predict outcome, with no significant differences between risperidone and haloperidol. The importance of an early adequate symptom control and the implementation of early intervention programs is highlighted.