Right unilateral and bitemporal ECT show similar symptom improvement in resistant schizophrenia

INTRODUCTION: Electroconvulsive therapy (ECT) is an effective treatment for resistant schizophrenia, although debate persists about the optimal electrode placement technique. Bitemporal stimulation (BTS) is the most commonly used, while right unilateral stimulation (RUS) is associated with fewer cognitive effects in other disorders. METHODS: Exploratory study including 17 patients randomized to BTS (n = 8) or RUS (n = 9). Symptoms and severity were assessed with the Positive and Negative Symptom Scale (PANSS) and Clinical Global Impression (CGI) scale, cognitive functions with Montreal Cognitive Assessment (MoCA) and Brief Assessment of Cognitive in Schizophrenia (BACS). Symptomatic changes, frequency and time of onset of side effects, changes in cognitive performance, and specific functions were compared. RESULTS: Both groups showed significant improvement in symptoms (ΔPANSS: BTS = 44.75 vs. RUS = 39.11; p = 0.724), with no differences in response rates (75% BTS vs. 44.4% RUS; p = 0.335). RUS required a lower stimulus to induce seizures (29.8 mC vs. 54 mC in BTS; p = 0.003). The BTS group showed deterioration in verbal fluency (BACS: p = 0.042), while the RUS showed improvement in motor speed (p = 0.046). There were no global differences in MoCA or BACS. CONCLUSION: Both techniques are equally effective in symptomatic reduction, but RUS could offer advantages as it requires less load and is associated with less deterioration in verbal fluency. These preliminary results have methodological limitations, mainly the sample size and lack of power calculation, but they may encourage further research. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT06972745.