Gender differences in the use of atypical antipsychotics in early-onset schizophrenia: a nationwide population-based study in Brazil

BACKGROUND: The use of atypical antipsychotics for the treatment of schizophrenia and other mental disorders in populations under 18 years of age is increasing worldwide. Little is known about treatment patterns and the influence of gender differences, which may be a predictor of clinical outcomes. The aim of this study was to investigate gender differences in the use of atypical antipsychotics 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 programme. Data were retrieved from a nationwide administrative database from 2008 to 2017. RESULTS: Of the 49,943 patients with EOS, 63.5% were males, and the mean age was 13.6 years old. The patients were using risperidone (62.5%), olanzapine (19.6%), quetiapine (12.4%), ziprasidone (3.3%) and clozapine (2.2%). We found gender differences, especially in the 13–17 year 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). Only in the 13 to 17 years age group were the prescribed doses of olanzapine (p = 0.012) and quetiapine (p = 0.041) slightly higher for males than for females. CONCLUSIONS: Our findings showed gender differences among patients diagnosed with EOS and who received atypical antipsychotics. More attention should be devoted to gender differences in research and clinical practice.