The Safety of 12-Weekly Monitoring of Neutrophil Count in Long-Term Clozapine Patients

IF 5 2区医学 Q1 PSYCHIATRY

Acta Psychiatrica Scandinavica Pub Date : 2025-05-03 DOI:10.1111/acps.13818

David Taylor, Siobhan Gee, Marinka Helthuis, Ebenezer Oloyede

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引用次数: 0

Abstract

Introduction

Clozapine is the only truly effective treatment for refractory schizophrenia, but its use is constrained by the requirements for frequent monitoring of neutrophil counts. In the UK during the COVID-19 pandemic, the frequency of clozapine blood monitoring was reduced in some units from 4-weekly to 12-weekly. We aimed to investigate the outcomes of reduced monitoring in long-term clozapine patients.

Methods

This was an anonymous, retrospective, observational cohort study. No restrictions were applied regarding care setting (i.e., outpatients or inpatients). All patients who registered for reduced frequency haematological monitoring from 1 March 2020 to 1 November 2022 were included and followed up till 1 August 2024. The primary outcome was death resulting from clozapine-induced agranulocytosis (CIA). Secondary outcomes were the proportion of patients with mild to moderate neutropenia during the follow-up period and the proportion of patients who reverted to standard monitoring during the study period.

Results

Amongst 1025 patients, there were no cases of agranulocytosis over 3365.9 patient-years of 12-weekly blood monitoring (incident rate 0.0 per 100 person-years). There were 43 episodes of mild neutropenia (so-called amber results—1.5–2.0 × 10⁹/L) or neutropenia (red results < 1.5 × 10⁹/L), an overall incident rate of 1.28 per 100 person-years. During follow-up, 41 patients (4%) reverted permanently to standard 4-weekly monitoring, and 157 patients (15%) temporarily interrupted reduced frequency monitoring but restarted 12-weekly monitoring before the end of the follow-up period. In total, 42 patients (4%) died during the observation period—no death was related to agranulocytosis.

Conclusion

Reducing the frequency of clozapine haematological monitoring to 12-weekly was safe in a group of long-term patients. No cases of agranulocytosis occurred and no deaths due to agranulocytosis were recorded. Most patients remained on extended-interval monitoring.

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查看原文本刊更多论文

长期氯氮平患者12周中性粒细胞计数监测的安全性

氯氮平是治疗难治性精神分裂症唯一真正有效的药物，但其使用受到频繁监测中性粒细胞计数要求的限制。在英国，在COVID-19大流行期间，氯氮平血液监测的频率在一些单位从4周减少到12周。我们的目的是调查长期氯氮平患者减少监测的结果。方法本研究为匿名、回顾性、观察性队列研究。没有对护理环境（即门诊病人或住院病人）施加限制。纳入了从2020年3月1日至2022年11月1日登记进行低频率血液学监测的所有患者，并随访至2024年8月1日。主要终点是氯氮平所致粒细胞缺乏症（CIA）导致的死亡。次要结局是随访期间轻度至中度中性粒细胞减少症患者的比例以及研究期间恢复标准监测的患者比例。结果在1025例患者中，在12周血液监测的3365.9患者-年（发病率为0.0 / 100人-年）中没有出现粒细胞缺乏症。有43例轻度中性粒细胞减少（所谓的琥珀色结果- 1.5 - 2.0 × 109/L）或中性粒细胞减少（红色结果- 1.5 × 109/L），总发病率为1.28 / 100人年。在随访期间，41例患者（4%）永久恢复标准的4周监测，157例患者（15%）暂时中断减少频率的监测，但在随访期结束前重新开始12周监测。观察期间共42例（4%）死亡，无粒细胞缺乏症相关死亡。结论降低氯氮平血液学监测频率至12周对长期患者是安全的。无粒细胞缺乏症病例发生，无粒细胞缺乏症死亡记录。大多数患者仍接受延长间隔监测。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Acta Psychiatrica Scandinavica 医学-精神病学

CiteScore

11.20

自引率

3.00%

发文量

135

审稿时长

6-12 weeks

期刊介绍： Acta Psychiatrica Scandinavica acts as an international forum for the dissemination of information advancing the science and practice of psychiatry. In particular we focus on communicating frontline research to clinical psychiatrists and psychiatric researchers. Acta Psychiatrica Scandinavica has traditionally been and remains a journal focusing predominantly on clinical psychiatry, but translational psychiatry is a topic of growing importance to our readers. Therefore, the journal welcomes submission of manuscripts based on both clinical- and more translational (e.g. preclinical and epidemiological) research. When preparing manuscripts based on translational studies for submission to Acta Psychiatrica Scandinavica, the authors should place emphasis on the clinical significance of the research question and the findings. Manuscripts based solely on preclinical research (e.g. animal models) are normally not considered for publication in the Journal.