Objective: Acute course of electroconvulsive therapy is effective in inducing remission from depression, but recurrence rate is unacceptably high following termination of electroconvulsive therapy despite continued pharmacotherapy. Continuation electroconvulsive therapy and maintenance electroconvulsive therapy have been studied for their efficacy in preventing relapse and recurrence of depression. The purpose of this meta-analysis was to examine the efficacy of continuation electroconvulsive therapy and maintenance electroconvulsive therapy in preventing relapse and recurrence of depression in comparison to antidepressant pharmacotherapy alone.
Methods: We searched MEDLINE, Embase, PsycINFO, clinicaltrials.gov and Cochrane register of controlled trials from the database inception to December 2016 without restriction on language or publication status for randomized trials of continuation electroconvulsive therapy and maintenance electroconvulsive therapy. Two independent Cochrane reviewers extracted the data in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews and meta-analyses. The risk of bias was assessed using four domains of the Cochrane Collaboration Risk of Bias Tool. Outcomes were pooled using random effect model. The primary outcome was relapse or recurrence of depression.
Results: Five studies involving 436 patients were included in the meta-analysis. Analysis of the pooled data showed that continuation electroconvulsive therapy and maintenance electroconvulsive therapy, both with pharmacotherapy, were associated with significantly fewer relapses and recurrences than pharmacotherapy alone at 6 months and 1 year after a successful acute course of electroconvulsive therapy (risk ratio = 0.64, 95% confidence interval = [0.41, 0.98], p = 0.04, risk ratio = 0.46, 95% confidence interval = [0.21, 0.98], p = 0.05, respectively). There was insufficient data to perform a meta-analysis of stand-alone continuation electroconvulsive therapy or maintenance electroconvulsive therapy beyond 1 year.
Conclusion: There are only a few randomized trials of continuation electroconvulsive therapy and maintenance electroconvulsive therapy. The preliminary and limited evidence suggests the modest efficacy of continuation electroconvulsive therapy and maintenance electroconvulsive therapy with concomitant pharmacotherapy in preventing relapse and recurrence of depressive episodes for 1 year after the remission of index episode with the acute course of electroconvulsive therapy.
Keywords: Depression; continuation electroconvulsive therapy; electroconvulsive therapy; maintenance electroconvulsive therapy; meta-analysis.