CLOZAPINE INDUCED BLOOD DYSCRASIA IN PAKISTAN: A RETROSPECTIVE STUDY

Abstract

Background: Clozapine is atypical antipsychotic particularly good at reducing the symptoms of schizophrenia, such as delusions and apathy. Despite being highly effective, the use of clozapine is limited due to the risk of blood disorders, known as blood dyscrasias. The objectives of the study were to determine how frequently clozapine-induced blood dyscrasia occur within study population, & outcomes associated with clozapine induced blood dyscrasia.

Methods: Medical data of patients was retrospectively reviewed in mentioned time period.  Before data collection, ethical approval was taken from Ethical Review Committee. The study excluded all OPD patients. Data collection was done using a pre-tested questionnaire that was adapted from a previous study. The sampling technique was non-probability convenience. The data was complied with proper coding in Microsoft Excel and then further analyzed in Statistical Package for Social Sciences for Windows (SPSS) version 29

Results: A total of 86 patients files were reviewed who were taking clozapine with or without other medicines. During the study period 23 patients (27%) developed blood dyscrasia. Out of which 64% were females. Majority of dyscrasia events happened in first three months (58%), followed by six months (31%), nine months (10%) and twelve months (1%). Among patients who developed blood dyscrasia most of the patients were diagnosed with with Scizophrenia and Bipolar Affective Disorder BAD (n =18, 67 %) followed by schizophrenia alone, BAD alone, drug induced psychosis, and schizophrenia plus agoraphobia. Out of 23 patients who developed blood dyscrasia 78% (n=18) patients were prescribed other medicines concomitantly with clozapine. The most commonly used drug was risperidone. Patients were also using valproate, and amlodipine/valsartan for the treatment of Epilepsy and Hypertension respectively. Majority (70%) adverse events were agranulocytosis.

Conclusion: Study emphasizes the critical need for diligent monitoring, especially in the early phases of clozapine treatment. Further research is needed to explore determinants for incidence and strategies for reducing the incidence of blood dyscrasia in patients taking clozapine. Future research should aim to identify predictive markers for these adverse effects to enhance patient safety and treatment efficacy.