Cessation of medication for people with schizophrenia already stable on chlorpromazine

 

Abstract

Background

Chlorpromazine, one of the first generation of antipsychotic drugs, is effective in the treatment of schizophrenia. For most people schizophrenia is a life-long disorder but about a quarter of those who have a first psychotic breakdown do not go on to experience further breakdowns. Most people with schizophrenia are prescribed antipsychotic drugs, although use is often intermittent. The effects of stopping medication are not well researched in the context of systematic reviews.

Objectives

To quantify the effects of stopping chlorpromazine for people with schizophrenia stable on this drug.

Search methods

We supplemented an electronic search of the Cochrane Schizophrenia Group Trials Register (March 2006) with reference searching of all identified studies.

Selection criteria

We included all relevant randomised clinical trials.

Data collection and analysis

We independently inspected citations and abstracts, ordered papers and re-inspected and quality assessed these. We independently extracted data and resolved disputes during regular meetings. We analysed dichotomous data using fixed effects relative risk (RR) and the 95% confidence interval (CI). For continuous data, where possible, we calculated the weighted mean difference (WMD). We excluded the data where more than 40% of people were lost to follow up.

Main results

We included ten trials involving 1042 people with schizophrenia stable on chlorpromazine. Even in the short term, those who remained on chlorpromazine were less likely to experience a relapse compared to people who stopped taking chlorpromazine (n=376, 3 RCTs, RR 6.76 CI 3.37 to 13.54, NNH NNH 4 CI 2 to 8). Medium term (n=850, 6 RCTs, RR 4.04 CI 2.81 to 5.8, NNH 4 CI 3 to 7) and long term data were similar (n=510, 3 RCTs, RR 1.70 CI 1.44 to 2.01, NNH 4 CI 3 to 6). People allocated to chlorpromazine withdrawal were not significantly more likely to stay in the study compared with those continuing chlorpromazine treatment (n=374, 1 RCT, RR 1.14 CI 0.55 to 2.35). In sensitivity analyses, there was a significant difference in the 'relapse' outcome between trials for those diagnosed according to checklist criteria compared to those with a clinical diagnosis.

Authors' conclusions

This review confirms clinical experience and quantifies the risks of stopping chlorpromazine medication for a group of people with schizophrenia who are stable on this drug. With its moderate adverse effects, chlorpromazine is likely to remain one of the most widely prescribed treatments for schizophrenia.

 

Plain language summary

Cessation of medication for people with schizophrenia already stable on chlorpromazine

The course of schizophrenia can be varied with some people experiencing a single episode of psychosis while others suffer repeated episodes. Often people with schizophrenia want to stop treatment with chlorpromazine once symptoms have subsided. This review highlights the risks of stopping chlorpromazine for those with established illness. Halting medication with chlorpromazine increases the risk of relapse over all time periods. Relapses are damaging and can be dangerous.

 

摘要

背景

使用chlorpromazine治療而穩定的精神分裂正患者如何停藥

Chlorpromazine是第一代抗精神病劑之一，能有效地治療精神分裂症。對大多數人而言，精神分裂症是影響終身的疾病，但大約有四分之一的病人第一次發作後，並未經歷再次的發作。大部分的精神分裂症患者都被投予抗精神病劑，即使經常是間斷使用。停藥產生的影響並沒有在系統性回顧文章中被妥善的研究。

目標

為了量化停藥的影響於使用chlorpromazine而症狀穩定的精神分裂症患者。

搜尋策略

我們增補了電子搜尋Cochrane Schizophrenia Group Trials Register (March 2006)以及所有相關的搜尋。

選擇標準

我們納入了所有相關的隨機臨床試驗。

資料收集與分析

我們獨立地檢視了標題和摘要，排序文獻和再檢視，評值品質。我們在常規的會議中獨立地取出資料並且解決爭論。我們使用固定效應的相對危險(fixed effects relative risk)和95%信賴區間(CI)去分析歧異的資料。如果是連續變項，我們計算了加權的平均差異(weighted mean difference)。我們排除了那些超過40%失去追蹤個案的資料。

主要結論

我們納入了十個包含1042位使用chlorpromazine而穩定的精神分裂症患者的試驗。即使是短期，那些仍然使用chlorpromazine的患者和停止使用chlorpromazine的患者相比，比較不會經驗到復發(relapse)(n = 376, 3 RCTs, RR 6.76 CI 3.37 to 13.54, NNH NNH 4 CI 2 to 8)。但中期(n = 850, 6 RCTs, RR 4.04 CI 2.81 to 5.8, NNH 4 CI 3 to 7)和長期(n = 510, 3 RCTs, RR 1.70 CI 1.44 to 2.01, NNH 4 CI 3 to 6)來看是差不多的。被分配到中斷chlorpromazine治療的病人和那些繼續chlorpromazine治療的病人相比，統計上並沒有比較可能會停留在試驗中(n = 374, 1 RCT, RR 1.14 CI 0.55 to 2.35)。在敏感度分析方面，那些以清單診斷準則(checklist criteria)為主的試驗和以臨床診斷為主的試驗，在復發結果上是有統計上的差異。

作者結論

此篇回顧文章證實了臨床的經驗和量化了停藥對於使用chlorpromazine而症狀穩定的精神分裂症患者的風險。Chlorpromazine雖有一些中等的副作用，但依然是最常用來治療精神分裂症的藥物之一。

翻譯人

本摘要由彰化基督教醫院謝明翰翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

精神分裂症的病程多變,有些人終其一生只發作一次，有些人則是反覆發作。通常精神分裂症患者使用chlorpromazine，一旦症狀緩解就想要停藥。此篇回顧文章強調停止使用chlorpromazine在疾病確定的病人身上是高風險的。停止chlorpromazine在任何時間都將增加復發的風險。復發是破壞性的且是危險的。