Background: The purpose of this study was to evaluate the long-term effect of repetitive transcranial magnetic stimulation (rTMS) as adjunctive treatment in patients with partial remission of major depressive disorder.
Methods: This was a 12-month, prospective, open-label study in patients meeting the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for nonpsychotic major depressive disorder who responded to 8 weeks of medication treatment but did not reach remission. All patients were assigned to receive 10 sessions of rTMS applied at the left dorsolateral prefrontal cortex. During the course of rTMS, the patients were still taking their usual medication. Patients were followed up for 12 months to determine the long-term antidepressant effect.
Results: There were nine patients (seven women and two men) who met the inclusion criteria and agreed to receive rTMS. The mean Hamilton rating scale for depression (HAM-D) score prior to treatment with rTMS was 12.89 ± 2.15. At 12 months after treatment, the mean HAM-D score was 6.45 ± 1.67 using a Friedman test, and in patients with partial remission of major depressive disorder, the HAM-D score significantly decreased after treatment with rTMS at 12 months (P = 0.001). Seven patients (77.78%) had reached the stage of remission (HAM-D < 8) after treating with rTMS at 12 months. There were no serious adverse events. One patient had vertigo after the first session of treatment and one patient felt scalp contractions during treatment, and both fully recovered within half an hour with no medical intervention.
Conclusion: For patients with major depressive disorder in partial remission, high frequency rTMS at the left dorsolateral prefrontal cortex may provide benefits in adjunctive treatment with well tolerability. Also, follow-up findings show a long duration of benefit.
Keywords: adjunctive; depression; long term; magnetic stimulation; remission.