Differential Effectiveness of Right Unilateral Versus Bilateral Electroconvulsive Therapy in Resistant Bipolar Depression

To the Editor: The article by Helle K. Schoeyen, M.D., Ph.D., et al. (1), published in the January 2015 issue of the Journal, compared electroconvulsive therapy (ECT) with right electrode placement with algorithm-based pharmacotherapy in treatment-resistant bipolar depression. The conclusion was that “the remission rate did not differ between the groups” and “remission rates remained modest regardless of treatment choice.” In order to avoid potential misunderstandings, we feel that the title of the article should have clearly stated that the ECT technique used was exclusively unilateral. Unilateral ECT is known to be less effective—and probably better tolerated—than bilateral ECT (2), and the reported 30% (drug treatment) to 35% (unilateral ECT) remission rates are similar to those found for augmentation strategies in nonbipolar-resistant depression in a real-world setting (3). Furthermore, in the results section, it is clearly apparent that unilateral ECT showed results for higher remission rates that nearly reached statistical significance, compared with algorithm-based drug treatment. Considering that the sample size was not large, suggesting that the study was likely underpowered, caution is needed when making conclusions such as those made in the abstract because they may prompt physicians to disregard ECT as a treatment option, which does not correspond with the available evidence. Before labeling a patient’s symptoms as “treatment-resistant” or “refractory,” months and repeated assays of ineffective drug treatment with drugs of different classes plus augmentation with other treatment methods (antipsychotics, somatic treatments, psychotherapy) is necessary (4, 5). Recent case reports indicate that ECT may abruptly terminate long-persisting psychiatric conditions. ECT is an orphan treatment because there is no marketing supporting it, and it carries some stigma and a bad reputation, which currently is scientifically unjustified. We simply want to emphasize this point in order to pay justice to both treatment options.