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Hematological Changes in Clozapine Users: A Study in a Brazilian Community Sample.
Natalia Daher1, Mateus Diniz2, Renan Biokino1
1Departamento de Psiquiatria, Escola Paulista de Medicina, Universidade Federal de São Paulo (EPM/UNIFESP), São Paulo, SP, Brazil. Programa de Esquizofrenia, Escola Paulista de Medicina, Universidade Federal de São Paulo (PROESQ-EPM/UNIFESP), São Paulo, SP, Brazil.
Trends in Psychiatry and Psychotherapy
|December 20, 2024
Summary
Clozapine use in Brazil led to a higher prevalence of blood dyscrasias, including anemia and thrombocytopenia. Most neutropenia cases were mild, suggesting a lower risk of severe neutropenia in clozapine patients.
Area of Science:
- Pharmacovigilance
- Hematology
- Psychiatry
Background:
- Clozapine is a superior antipsychotic for treatment-resistant schizophrenia.
- Hematological side effects limit clozapine's global use.
- This study investigated clozapine-associated hematological abnormalities in Brazil.
Purpose of the Study:
- To determine the prevalence of blood dyscrasias in clozapine users.
- To assess the incidence and severity of neutropenia.
- To explore potential associations between neutropenia and patient demographics.
Main Methods:
- Retrospective analysis of 6,160 complete blood counts from 486 patients.
- Real-world data from a community center in Goiás, Brazil (2011-2018).
- Logistic regression used to assess neutropenia risk factors (sex, age).
Main Results:
- 37.4% of patients exhibited blood dyscrasias.
- Anemia (23.6%), eosinophilia (13.7%), and thrombocytopenia (9.46%) were most common.
- Neutropenia occurred in 4.52%, primarily mild (3.9%) or moderate (0.62%); no agranulocytosis.
Conclusions:
- Clozapine users in this cohort had a higher prevalence of blood dyscrasias than the general Brazilian population.
- Mild and transient neutropenia was common, with a low risk of severe cases.
- Further investigation into other blood dyscrasias associated with clozapine is warranted.
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