SU114. Switching to Clozapine Treatment in Patients With Schizophrenia: The Clinical Course, Remission, and Augmentation of Treatment After the Switch

Abstract

Background: This study aims to compare clinical features of schizophrenia patients before and after clozapine initiation and to investigate the clinical course of illness, clinical features, remission state, and augmentation methods under clozapine treatment. Methods: A total of 122 consecutive outpatients diagnosed with DSM-IV criteria for schizophrenia and receiving clozapine treatment were included. Patients were assessed with the Structured Clinical Interview for DSM-IV Axis I Disorders, Positive and Negative Syndrome Scale, Clinical Global Impression Scale, Global Assessment of Functioning, Calgary Depression Scale for Schizophrenia, Panic Agoraphobia Scale, Yale-Brown Obsessive Compulsive Scale, and the World Health Organization Disability Assessment Schedule-2.0 to determine the severity of psychopathology and comorbid symptoms, as well as the level of functioning and disability. The remission state of the patients was assessed utilizing the Schizophrenia Working Group’s remission criteria for schizophrenia. Results: The number of psychotic relapses, hospitalizations, and suicide attempts along with alcohol-drug misuse rates declined after the initiation of clozapine. The study group consisted of schizophrenia patients using clozapine for a mean period of 9 years, and 44.5% of these patients were found to be in a symptomatic remission state. No relationship was shown between remission state and clozapine dose/plasma levels. Education level was found to be higher, work status better, and comorbid symptom severity lower in remitted patients. There was no difference between remitted and not remitted patients in terms of the duration of clozapine use and age at disease onset. Education level, positive and negative symptom severity predicted achievement of remission on clozapine. The augmentation strategies were examined in patients showing partial response to clozapine, and combined antipsychotic drug use was found to be the most prevalent method utilized. Patients on augmentation treatment were on higher daily clozapine doses and their remission rates were lower. In addition, the severity of psychopathology related with schizophrenia and comorbid symptoms, the level of functioning and disability were worse in this particular patient group. History of antipsychotic combination use prior to clozapine was found to predict the future use of clozapine augmentation. Conclusion: Shortening the duration of switch to clozapine and avoiding antipsychotic combinations prior to clozapine use should both be considered as important goals in the management of treatment resistant schizophrenia.