(P-074) Sex Difference, Label Indications and Trend in Atypical Antipsychotics Use in Early-onset Schizophrenia: A Nationwide Cross-sectional Study

Background: There continue to be significant knowledge gaps regarding the treatment pattern, the practice of off-label use outside the approved age, and the influence of sex difference in the treatment of schizophrenia in populations under 18 years of age.

Objectives: The objective of this study was to investigate patterns of atypical antipsychotics use and sex differences in patients with early-onset schizophrenia (EOS) assisted by the public health system in Brazil.

Methods: We conducted a cross-sectional study of outpatients with EOS aged 10 to 17 years who received at least one provision of atypical antipsychotics (clozapine, olanzapine, risperidone, quetiapine, or ziprasidone) from a large Brazilian pharmaceutical assistance program on the Public Health System in Brazil. Data were retrieved from a nationwide administrative database (SIA/SUS) from 2008 - 2017. Atypical antipsychotics were classified as “off-label use by indication of EOS and age” according to the information registered by the Brazilian Health Regulatory Agency and U.S. Food and Drug Administration.

Results: Of the 49,943 patients with EOS, 63.5% were males, and 36.5% was aged 10 to 12 years (p < 0.001) and 63.5% was 13 to 17 years. The patients were using risperidone (62.5%), olanzapine (19.6%), quetiapine (12.4%), ziprasidone (3.3%) and clozapine (2.2%). The off-label use of antipsychotics by age was 40.7%. The sex differences were found especially in the 13-17-years old age group (65.1% for males vs. 34.9% for females, p<0.001), in the use of risperidone (72.1% for males vs. 27.9% for females, p<0.001) and olanzapine (66.5% for males vs. 33.5% for females, p<0.001) with male predominance.

Conclusions: Our findings showed overuse off-label in children, which could bring safety concerns. There were sex differences among patients diagnosed with EOS and who received atypical antipsychotics. More attention should be devoted to sex differences in research as well as to the potential risks associated with off-label use in clinical practice.