Acceptability, safety and tolerability of antidepressant repetitive transcranial magnetic stimulation for adolescents: A mixed-methods investigation

Objective: Major depressive disorder (MDD) is relatively common in adolescence, with far-reaching impacts. Current treatments frequently fail to alleviate depression severity for a substantial portion of adolescents. Repetitive transcranial magnetic stimulation (rTMS) may assist with this unmet clinical need. However, little is known about adverse events (AEs) experienced by adolescents receiving rTMS, subjective treatment experiences of adolescents and their parents, or treatment acceptability. Methods: Fourteen adolescents (16.5 years +/- 1.2; 71.4% female) with MDD received 20 sessions of either high-frequency (10 Hz; n = 7) left dorsolateral prefrontal cortex (DLPFC) or low-frequency (1 Hz; n = 7) right DLPFC rTMS. AEs were monitored at baseline and at weekly intervals via New York State Psychiatric Institute Side Effects Form for Children and Adolescents. Eight adolescents and nine parents participated in interviews regarding subjective treatment experience, analysed via content analysis. Results: Drowsiness and lethargy were common AEs, reported by 92.3% of participants in week one. Number of AEs decreased throughout treatment course (after 5 treatments: M = 11.23, SD = 5.00; after 20 treatments: M = 8.92, SD = 5.95). Thirty-five AEs emerged during treatment, most commonly transient dizziness. Frequency, severity, and number of AEs reported were equivalent between treatment groups. Treatment adherence and satisfaction were high. Qualitative findings identified three themes relating to rTMS experience: Preparation and connection; Physical experience of treatment; and Perceived role of treatment. Limitations: Sample size was small, therefore findings are preliminary. Conclusions: rTMS was an acceptable treatment for adolescent MDD, from both adolescents' and parents' perspectives, and was safe and well-tolerated, as AE frequency and type did not differ from rTMS treatment courses in adults.