The priming effect of repetitive transcranial magnetic stimulation on clinical response to electroconvulsive therapy in treatment-resistant depression: a randomized, double-blind, sham-controlled study

Abstract Background Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression (TRD). However, due to response delay and cognitive impairment, ECT remains an imperfect treatment. Compared to ECT, repetitive transcranial magnetic stimulation (rTMS) is less effective at treating severe depression, but has the advantage of being quick, easy to use, and producing almost no side effects. In this study, our objective was to assess the priming effect of rTMS sessions before ECT on clinical response in patients with TRD. Methods In this multicenter, randomized, double-blind, sham-controlled trial, 56 patients with TRD were assigned to active or sham rTMS before ECT treatment. Five sessions of active/sham neuronavigated rTMS were administered over the left dorsolateral prefrontal cortex (20 Hz, 90% resting motor threshold, 20 2 s trains with 60-s intervals, 800 pulses/session) before ECT (which was active for all patients) started. Any relative improvements were then compared between both groups after five ECT sessions, in order to assess the early response to treatment. Results After ECT, the active rTMS group exhibited a significantly greater relative improvement than the sham group [43.4% (28.6%) v. 25.4% (17.2%)]. The responder rate in the active group was at least three times higher. Cognitive complaints, which were assessed using the Cognitive Failures Questionnaire, were higher in the sham rTMS group compared to the active rTMS group, but this difference was not corroborated by cognitive tests. Conclusions rTMS could be used to enhance the efficacy of ECT in patients with TRD. ClinicalTrials.gov: NCT02830399.