Tiagabine in the treatment of acute affective episodes in bipolar disorder

 

Abstract

Background

Bipolar disorder is a common recurrent illness with high levels of chronicity. Treatment resistance persists despite the use of established medications, such as lithium and valproate. New medications are required for the treatment of refractory cases. Some open-label reports have suggested that the anticonvulsant tiagabine may be efficacious in bipolar disorder. There is a need to clarify the evidence available, in the form of randomised controlled trials, for its use in the treatment of acute affective episodes in bipolar disorder

Objectives

To review the evidence for the efficacy and acceptability of tiagabine in the treatment of acute mood episodes in bipolar disorder.

Search methods

The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (CCDANCTR-Studies and CCDANCTR-References) was searched on 12/2/2008.

Reference lists of relevant papers and major textbooks of mood disorder were searched. Handsearches were done (specialist journals and conference proceedings). Authors, other experts in the field and pharmaceutical companies were contacted for knowledge of suitable published or unpublished trials.

Selection criteria

Randomised controlled trials, which compared tiagabine with placebo or with active agents in the treatment of any acute mood episodes in bipolar disorder, were selected. Studies of participants with bipolar disorder were to be included. Subjects could be of either sex and of all ages.

Data collection and analysis

Data extraction and methodological quality assessment were performed independently by two reviewers. For analysis, relative risk was used for binary efficacy outcomes and the weighted mean difference or standardised mean difference was used for continuously distributed outcomes

Main results

We did not find any studies which fulfilled the Cochrane criteria of randomised controlled trials. However, one uncontrolled open label study and one case series were found. There were also three case reports/series of acute treatment which were continued into maintenance therapy, and one open non-randomised study with this design. The results of these studies are inconsistent .

Authors' conclusions

We found no randomised controlled trials of tiagabine in bipolar disorder. In the reported cases, a significant proportion of patients suffered episodes of syncope or seizure. There is a need for randomised controlled trials examining the efficacy and acceptability of tiagabine in the acute treatment of bipolar disorder, after the nature of these episodes has been clarified.

 

Plain language summary

Tiagabine to treat acute affective episodes in bipolar disorder

This systematic review investigated the evidence base for the efficacy and acceptability of tiagabine compared to placebo and other pharmacological agents in the acute treatment of bipolar disorder. No randomised controlled trials were found. Currently, there is insufficient evidence on which to base any recommendations regarding the use of tiagabine in acute treatment of bipolar illness, either in monotherapy or as an adjunctive treatment. A significant proportion of patients suffered episodes of syncope or seizure. There is a need for randomised controlled trials examining the efficacy and acceptability of tiagabine in the acute treatment of bipolar disorder, after the nature of these episodes has been clarified.

 

摘要

背景

使用Tiagabine治療雙極性疾患急性期:療效與接受度

雙極性疾患是常見會復發又伴隨高度慢性化的疾病。即便使用像鋰鹽及valproate有療效的藥物治療，治療頑抗仍存在著。對於治療頑抗的個案，需要有新的藥物。一些開放標示(openlabel)的研究報告建議抗癲癇藥物tiagabine可能對雙極性疾患有療效。因此有需要就現有針對雙極性疾患急性發作的隨機對照試驗來進一步驗證他們的證據“。

目標

回顧Tiagabine治療雙極性疾患急性期療效與接受度的證據。

搜尋策略

於2005年10月13日搜尋下列資料庫: The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (CCDANCTRStudies and CCDANCTRReferences), The Cochrane Controlled Clinical Trials Register (CCCTR), EMBASE, MEDLINE, LILACS, PsycLIT andPsyndex。我們也搜尋相關文章的引用文獻以及有關情緒疾患的參考書，也動手找尋專業期刊以及研討會的會議記錄；對於在這領域中的作者以及其他專家，還有藥廠等會去徵詢關於發表或未發表的試驗結果。

選擇標準

選擇關於雙極性疾患急性期的治療中，比較Tiagabine與安慰劑或其他有效藥物的隨機對照試驗，受試者是雙極性疾患的研究才會被納入，個案男、女皆可而且不限年齡。

資料收集與分析

兩位審查者獨立進行數據擷取以及方法學的品質評估。對於二元的療效預後數據會去計算相對風險(relative risk)，而對於連續性分布的預後數據則去計算加權平均差或標準平均差。

主要結論

我們沒有發現任何符合the Cochrane criteria的隨機對照試驗，不過卻有一個沒有對照組的開放標示研究以及一個病例系列 (case series) 研究，另外還有三個急性期治療後進入維持治療的個案報告，以及一個採同樣設計的開放非隨機的研究。這些研究的結果並沒有一致性。

作者結論

我們沒有發現有使用tiagabine在雙極性疾患的隨機對照試驗。在個案報告中，有顯著比例的患者出現昏厥(syncope)或抽搐(seizure)的情況。未來有需要一些隨機對照試驗來檢視tiagabine治療雙極性疾患急性期的療效以及接受度，不過前提是要先釐清每次發作的病程。

翻譯人

本摘要由彰化基督教醫院李柏賢翻譯。

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

總結

這篇系統性回顧以證據基礎探查tiagabine相較於安慰劑及其他藥物在雙極性疾患急性治療的療效及接受度。我們沒有找到任何隨機對照試驗。目前沒有足夠的證據來支持將tiagabine以單一或附加在其他藥物方式用於雙極性疾患的急性期。顯著比例的患者出現暈厥或抽搐的情況。未來有需要一些隨機對照試驗來檢視tiagabine治療雙極性疾患急性期的療效以及接受度，不過前提是要先釐清每次發作的病程。