An open-label feasibility study of repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant depression in the New Zealand healthcare context.

Aim: Major depressive disorder (MDD) poses a significant and growing burden on the New Zealand population. It is a leading cause of disability, and resistance to currently offered treatments is common. Repetitive transcranial magnetic stimulation (rTMS) is a treatment offered internationally demonstrating good efficacy and few reports of side effects. It is an intervention that requires daily visits to a clinic over a period of at least four weeks. This study aimed to investigate the effectiveness and acceptability of offering rTMS as a treatment for MDD in the setting of New Zealand healthcare systems.

Method: This was a naturalistic, open-label pilot study in which 30 patients with moderate-to-severe treatment-resistant MDD were treated with a course of rTMS (10 Hz) daily over the left dorsolateral prefrontal cortex for four weeks (20 sessions). Primary endpoint was response to treatment, stratified into non-responder, partial responder or responder based on the Montgomery-Åsberg Depression Rating Scale (MADRS) at the end of treatment compared to baseline (<25% reduction, 25-50% reduction, and >50% reduction respectively). Participant remission was also noted as reaching a score of ≤10.

Results: Thirty participants completed the full course of treatment (16 women, mean age 47y, range 19-77y), with a mean baseline MADRS of 32.0 (range 21-48). Twelve participants were classified as responders, six as partial responders, and 12 as non-responders. Of the responders, nine were in remission at the end of treatment. Minimal side effects were reported.

Conclusion: Daily sessions of rTMS were successfully administered and were effective in treatment-resistant MDD. The treatment was accessible and well tolerated by the majority of the study participants and should be made available to MDD patients in New Zealand as a treatment option.