Alternate day dTMS combined with SSRIs for chronic treatment resistant depression: A prospective multicenter study

Introduction: Chronic treatment resistant depression takes a substantial toll on patients’ quality of life and alternative treatment options are limited. This prospective multicenter study evaluated the safety, tolerability and efficacy of four weeks of thrice-a-week deep transcranial magnetic stimulation (dTMS) in combination with selective serotonin reuptake inhibitors (SSRIs). Methods: Forty patients who failed to respond during a 16-week double-blind placebo controlled (DBPC) trial of dTMS or sham dTMS as monotherapy were screened and started a treatment of previously tolerable but ineffective SSRI. After ten days of medication, high frequency dTMS was added three times a week for four weeks. Results: dTMS combined with SSRIs was well tolerated, with only headaches as a related adverse event (n = 4), which did not cause drop outs. Six patients were excluded from analysis: 1 was missing screening data and 5 received less than 10 sessions. Out of 34 patients included in this study, 12 (35.3%) patients remitted (HDRS-21 < 10). No significant differences were found between patients who had received sham or active dTMS in the earlier DBPC multicenter trial. Limitations: This was a small scale open study of dTMS with SSRIs in patients that failed to respond during a DBPC dTMS trial, although a carryover effect cannot be excluded. Comparative efficacy of dTMS with and without SSRIs and specific dosing and protocol parameters warrant specifically-designed large-scale controlled studies. Conclusions: Thrice weekly dTMS at 120% motor threshold(MT), 10 HZ, 3‑s trains, 20‑s intervals, 2400 daily pulses, can augment formerly ineffective SSRI treatment.