Cognitive preservation advantage and efficacy balance of magnetic seizure therapy in adolescent Major Depressive Disorder: a randomized controlled trial revealing efficacy cognition decoupling phenomenon.

Abstract

Objective: To compare magnetic seizure therapy (MST) and modified electroconvulsive therapy (MECT) in adolescent major depressive disorder (MDD) regarding cognitive protection (assessed via the Montreal Cognitive Assessment, MoCA) and suicidality improvement (assessed via the Columbia-Suicide Severity Rating Scale, C-SSRS), with a focus on cognitive subdomains and the mediating role of cognitive changes.

Methods: This analysis stems from a prospective, assessor-blinded randomized controlled trial (RCT, ChiCTR2500098032) conducted from March 1 to April 30, 2025, at Shandong Mental Health Center, enrolling 120 adolescents aged 13-18 with MDD, randomized 1:1 to MST (n=60) or MECT (n=60). Primary outcome was the Beck Depression Inventory-II (BDI-II) percentage reduction; secondary outcomes included MoCA subdomain scores, C-SSRS suicidality, and adverse events (CTCAE 5.0). Correlation, mediation (Sobel test), and repeated-measures ANOVA (RM-ANOVA) assessed the cognitive-suicidality relationship. Assessments occurred at baseline and 7 days post-treatment.

Results: MECT yielded a higher BDI-II reduction rate, with no significant difference in response rate. MST significantly improved MoCA total score, particularly in memory, orientation, and executive function subdomains. MST enhanced suicidality outcomes, with a higher remission rate. The correlation between MoCA change and suicidality improvement was stronger in MST, with mediation analysis indicating a partial mediating role of MoCA improvement in MST. MST showed fewer adverse events and shorter reorientation time.

Conclusions: In adolescent MDD, MST offers efficacy comparable to MECT for depression relief, with superior cognitive protection (especially memory, orientation, and executive function) and safety. The association between cognitive improvement and suicidality reduction suggests MST may indirectly mitigate suicide risk via cognitive preservation, providing a novel treatment option. Multicenter, long-term studies are needed to confirm these findings.