The primary aim of the study was to test the hypothesis that relapse prevention with continuation electroconvulsive therapy (ECT) plus pharmacotherapy is more effective than pharmacotherapy alone after a course of ECT for depression.
A multicenter, nonblinded, randomized controlled trial with 2 parallel groups was performed from 2008 to 2012 in 4 hospitals in Sweden. Patients eligible had unipolar or bipolar depression and had responded to a course of ECT. The patients (n = 56) were randomly assigned (1:1) to receiving either 29 treatments of continuation ECT with pharmacotherapy or pharmacotherapy alone for 1 year. The pharmacotherapy consisted of antidepressants (98%), lithium (56%), and antipsychotics (30%). The main outcome was relapse of depression within 1 year. Relapse was defined as 20 or more points on the Montgomery Åsberg Depression Rating Scale or inpatient psychiatric care or suicide or suspected suicide. All 56 patients randomized were analyzed according to an intention to treat analysis.
Sixty-one percent of the patients treated with pharmacotherapy versus 32% of the patients treated with ECT plus pharmacotherapy relapsed within 1 year (P = 0.036). The Cox proportional hazard ratio was 2.32 (1.03–5.22).
Cognitive function and memory measures were stable for patients without relapse in both groups.
One suspected suicide and 3 suicide attempts by intoxication occurred, all in the pharmacotherapy-alone group.
The post-ECT relapse rates were substantial in both treatment groups with a statistically significant advantage for combined treatment with pharmacotherapy and continuation ECT. Further studies are needed to define indications for continuation ECT, pharmacotherapy, and their combination.