Augmentation of Clozapine Due to Inadequate Treatment Response in Schizophrenia: Comparison of Patients with Augmented and Non-augmented Treatments.

Objective: Clozapine is considered to be a gold standard antipsychotic in treatment resistant schizophrenia. This study aims to investigate clozapine augmentation methods utilized in schizophrenia and compare the sociodemographic characteristics, clinical features and remission states of patients whose treatments are augmented and not. Method: This study included 122 outpatients diagnosed with DSM-IV schizophrenia. 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 II. The remission state of the patients was assessed utilizing the Remission in Schizophrenia Working Group criteria for schizophrenia. Results: Combined antipsychotic drug use was the most prevalent method utilized for clozapine augmentation. 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: Adding a second antipsychotic seems to be the most common method of augmenting clozapine treatment in schizophrenia. The group of patients whose clozapine treatment is augmented appears to represent a "more difficult to treat" patient group before clozapine is initiated. [ABSTRACT FROM AUTHOR]