Abstract

The IC-SOHO study was designed to supply information on antipsychotic treatments in the real clinical practice by assessment of a large and diverse sample population with schizophrenia. This document describes the findings of the first 6 months of IC-SOHO in Latin America. To date, this is the largest observational study of its type in this region. In this observational and prospective study, those outpatients with schizophrenia, who require a change or initiation of antipsychotic medication are hospitalized. Effectiveness was evaluated using the Clinical Global Impression-Seriousness (CGI-S) grading scale. Tolerability was assessed by questionnaires on adverse events and weight measurements. Herein, the comparisons between olanzapine (monotherapy), risperidone (monotherapy) and conventional antipsychotics (monotherapy and combined therapy) are presented. As a whole, 7,658 patients participated in the IC-SOHO; n = 2,671 from 11 countries of Latin America that were included in this report. At 6 months, the proportion of patients who responded to olanzapine was significantly greater than those who responded to risperidone or conventional antipsychotics (p < 0.001). Patients from the olanzapine group had greater improvements in all the symptom domains, including general, positive, negative, depressive and cognitive symptoms in comparison with risperidone (p < 0.05) or conventional antipsychotics (p < 0.001). Extrapyramidal symptoms (EPS) and tardive dyskinesia (TD) decreased from baseline in the groups treated with olanzapine and risperidone, but increased in the conventional group. Adverse events related with the sexual function were more prominent in the conventional group. Weight gain was observed in each treatment group, although the patients from the olanzapine group had greater weight gain followed by those of risperidone and then by those of conventional antipsychotics. Our findings in this population of the Latin American sample emulate the results of other studies in different samples, where it was found that olanzapine was more effective and better tolerated than risperidone or conventional antipsychotics.