H-coil repetitive transcranial magnetic stimulation for treatment resistant major depressive disorder: An 18-week continuation safety and feasibility study

Abstract

Objective: Evidence has shown that repetitive transcranial magnetic stimulation (rTMS) can be effective as an acute treatment for major depressive disorder (MDD). However, few studies have examined the safety and feasibility of rTMS as a long-term\continuation treatment. Deep-TMS is a novel tool enabling deeper stimulation than standard coils. The current study examined the safety and feasibility of repetitive deep-TMS continuation treatment for MDD over the course of 18 weeks, following 4 weeks of acute treatment.

Method: A total of 29 MDD patients were enrolled in the study. rTMS sessions (20 Hz) were given for a total of 22 weeks, divided into: 4 weeks of acute daily treatments, followed by 18 weeks of continuation treatments. Clinical evaluations were performed weekly throughout the study.

Results: A significant decrease from baseline in Hamilton Depression Rating Scale (HDRS) score was found at the end of the acute phase, and maintained throughout the study (P < 0.0001). The Kaplan-Meier estimated probability of response was 46.15% (SE = 9.78%) at the end of the acute phase, and 81.12% (SE = 9.32%) at the end of the study (22 weeks). probability of remission at the end of the acute phase was 26.92% (SE = 8.70%) and 71.45% (SE = 10.99%) at the end of the study. Response in the acute phase was indicative of response in the continuation phases. The procedure was generally well tolerated and no adverse events were reported.

Conclusion: The results suggest that H-coil deep-TMS administered continuation treatment can help maintain an antidepressant effect for 18 weeks, following 4 weeks of acute treatment.

Keywords: Transcranial magnetic stimulation (TMS); continuation treatment; major depressive disorder; medication resistance; neuromodulation.