Cognitive Preservation and Antidepressant Efficacy of Magnetic Seizure Therapy in Adolescent Treatment Resistant Major Depressive Disorder in China: A Randomized Controlled Trial

Objective To compare the antidepressant efficacy, cognitive impact, and safety profile of magnetic seizure therapy (MST) vs modified electroconvulsive therapy (MECT) in Chinese adolescents with treatment-resistant major depressive disorder (MDD). Methods This single-center, evaluator-blinded, prospective randomized controlled trial enrolled 120 adolescents aged 13-18 years diagnosed with treatment-resistant MDD. Participants were randomly assigned to either the MST group or the MECT group (n = 60 per group). The primary outcome was improvement in depressive symptoms measured by the Beck Depression Inventory-II (BDI-II) score reduction rate. Secondary outcomes included changes in cognitive function assessed by the Montreal Cognitive Assessment (MoCA), time to reorientation, and adverse event incidence per CTCAE 5.0 criteria. Results The BDI-II reduction rate was significantly higher in the MECT group (51.8%) compared to the MST group (46.5%) ( P < 0.001), though clinical response rates were similar (90.0% vs 91.1%). The MST group showed significant improvement in MoCA total score, whereas the MECT group demonstrated slight declines ( P < 0.001). MST was associated with greater cognitive preservation (+0.96 vs −0.36 MoCA score), fewer adverse events (28.9% vs 64.0%, P < 0.001), and faster reorientation (6.9 ± 1.8 min vs 18.7 ± 6.8 min, P < 0.001). Conclusion MST exhibited comparable antidepressant efficacy to MECT while offering superior cognitive protection and safety in adolescents with treatment-resistant MDD. These findings suggest MST may be a preferred treatment option balancing symptom relief with neurodevelopmental preservation.