Electroconvulsive therapy (ECT) is one of the most effective treatments for major depressive disorder (MDD), especially in cases of treatment-resistant MDD. Due to their pharmacological profiles, benzodiazepines (BZDs) are suspected to decrease the efficacy of ECT. Current recommendations from scientific societies suggest gradual reduction or discontinuation of BZDs before the first ECT [1American Psychiatric Association. Committee on Electroconvulsive Therapy; Weiner RD. The practice of electroconvulsive therapy: recommendations for treatment, training, and privileging. A Task Force Report of the American Psychiatric Association. American Psychiatric Publishing; 2001.

Cliquez ici pour aller à la section Références]. However, some studies revealed that BZDs had no negative impact on clinical efficacy of ECT in patients with MDD [2Galvez V., Loo C.K., Alonzo A., Cerrillo E., Menchon M., Crespo J.M., Urretavizcaya M. Do benzodiazepines moderate the effectiveness of bitemporal electroconvulsive therapy in major depression? J Aff Disorders 2013 ;  150 (2) : 686-690 [cross-ref]

Cliquez ici pour aller à la section Références]. The current study investigated the effect of BZDs on ECT-induced clinical outcomes and on ECT parameters in patients with MDD.

Seventy patients with MDD receiving ECT, using dose-titration method, were retrospectively included. Among them, 22 received BZDs. We investigated the effect of BZDs onECT-induced changes in severity of depression using the Montgomery–Asberg Depression Rating Scale (MADRS) and on seizure parameters (seizure threshold, clinical and EEG seizure duration). Primary outcome was the number of patients who achieved remission (MADRS<10) after ECT. Changes in clinical ratings (MADRS) before and after ECT course, changes in ECT parameters (number of ECT sessions, seizure parameters) and number of responders were also compared between BZDs and non-BZDs groups.

In the non-BZDs, lower remission rates (52.0% versus 81.2%; P=0.02; Figure 1) and smaller decreases in MADRS scores (mean−21.9±standard deviation 11.5 versus−28.9±10.5; P=0.02) were observed than in the BZDs group after ECT. There were no significant differences between the two groups regarding ECT parameters and number of responders.

BZDs increased the clinical efficacy of ECT when delivered using dose-titration method and bitemporal stimulation in patients with MDD. The concomitant use of GABAergic drugs such as BZDs may potentiate the GABAergic effect observed during ECT course. Further studied are needed to understand the interaction between BZDs and ECT on clinical outcomes.