Effects of electroconvulsive therapy on cognitive function, depressive symptoms, and suicidal ideation in adolescents with major depressive disorder: A prospective observational study.

Background: Adolescent depression and suicide are significant issues, with insufficient solutions available. Concerns about electroconvulsive therapy (ECT)'s cognitive side effects have restricted its use in adolescents with major depressive disorder (MDD). Clarifying ECT's cognitive, antidepressant, and anti-suicidal effects is crucial to inform its clinical application.

Methods: This prospective observational study enrolled 60 adolescents with DSM-5-diagnosed MDD and scheduled for bifrontal ECT, between October 2023 and March 2025. Cognitive outcomes were assessed using the Cambridge Neuropsychological Test Automated Battery, and clinical outcomes using the 24-item Hamilton Depression Rating Scale (HAMD-24) and the Beck Scale for Suicide Ideation (BSI). Assessments were conducted at four points: before ECT (T0), and at 1 day (T1), 2 weeks (T2), and 4 months after ECT courses(T3).

Result: Cognitive assessments showed mild declines in spatial and verbal memory at T1 (d = 0.376 and 0.364, respectively), which recovered by T2. Working memory, attention, and executive function did not decline at T1; instead, improvements emerged in 2 weeks and persisted at 4 months. No prolonged cognitive impairment was observed after four months. Following the ECT course, depressive symptoms significantly decreased (d = 4.20), with 78.3 % response and 25.0 % remission. Suicidal ideation also showed a marked reduction (d = 2.70). Other adverse events were generally mild and transient, with headaches being most frequent (58.3 %).

Conclusion: ECT was associated with transient impairments in specific cognitive domains, but prolonged impairments were not observed. Additionally, ECT provides a rapid and powerful effect for depressive symptoms and suicidal ideation in adolescents. Therefore, in adolescents with MDD and elevated suicide risk, early consideration of ECT may be warranted.