Bitemporal Versus High-Dose Unilateral Twice-Weekly Electroconvulsive Therapy for Depression (EFFECT-Dep): A Pragmatic, Randomized, Non-Inferiority Trial

Objective: ECT is the most effective treatment for severe depression. Previous efficacy studies, using thrice-weekly brief-pulse ECT, reported that high-dose (63 seizure threshold) right unilateral ECT is similar to bitemporal ECT but may have fewer cognitive side effects. The authors aimed to assess the effectiveness and cognitive side effects of twice-weekly moderate-dose (1.5x seizure threshold) bitemporal ECT with high-dose unilateral ECT in real-world practice. Method: This was a pragmatic, patient-and rater-blinded, noninferiority trial of patients with major depression (N=138; 63% female; age=56.7 years [SD=14.8]) in a national ECT service with a 6-month follow-up. Participants were independently randomly assigned to bitemporal or high-dose unilateral ECT. The primary out come was change in the 24-item Hamilton Depression Rating Scale (HAM-D) score after the ECT course; the prespecified noninferiority margin was 4.0 points. Secondary outcomes included response and remission rates, relapse status after 6 months, and cognition. Results: Of the eligible patients, 69 were assigned to bitemporal ECT and 69 to unilateral ECT. High-dose unilateral ECT was noninferior to bitemporal ECT regarding the 24-item HAM-D scores after the ECT course (mean difference=1.08 points in favor of unilateral ECT [95% CI=21.67 to 3.84]). There were no significant differences for response and remission or 6-month relapse status. Recovery of orientation was quicker following unilateral ECT (median=19.1 minutes versus 26.4 minutes). Bitemporal ECT was associated with a lower percent recall of autobiographical information (odds ratio=0.66) that persisted for 6 months. Conclusions: Twice-weekly high-dose unilateral ECT is not inferior to bitemporal ECT for depression and may be preferable because of its better cognitive side-effect profile.