Long-term efficacy of repeated daily prefrontal transcranial magnetic stimulation (TMS) in treatment-resistant depression

Abstract

Background: A few studies have examined the durability of transcranial magnetic stimulation (TMS) antidepressant benefit once patients remitted. This study examined the long-term durability of clinical benefit from TMS using a protocol-specified TMS taper and either continuation pharmacotherapy or naturalistic follow-up.

Methods: Patients were remitters from an acute double-blind sham-controlled trial of TMS (n = 18), or from an open-label extension in patients who did not respond to the acute trial (n = 43). Long-term durability of TMS acute effect was examined in remitters over a 12-week follow-up. Relapse, defined as 24-item Hamilton Depression Rating Scale (HDRS-24) ≥20, was the primary outcome.

Results: Of 61 remitters in the acute trial, five entered naturalistic follow-up and 50 entered the TMS taper. Thirty-two patients completed TMS taper and 1-, 2-, and 3-month follow-up. At 3-month visit, 29 of 50 (58%) were classified as in remission (HDRS-24 ≤10), two of 50 (4%) as partial responders (30%≤ HDRS-24 reduction <50% from baseline), and one of 50 (2%) met criteria for relapse. During the entire 3-month follow-up, five of the 37 patients relapsed (relapse rate = 13.5%), but four of them regained remission by the end of the study. The average time to relapse in these five patients was 7.2 ± 3.3 weeks. Patients who relapsed had higher depression scores at 1 month.

Conclusions: While one third of the sample was lost to follow-up, our results demonstrate that most patients contributing to observations experienced persistence of benefit from TMS followed by pharmacotherapy or no medication. Longer follow-up and more rigorous studies are needed to explore the true long-term durability of remission produced by TMS.

Conflict of interest statement

Conflict of Interest. Drs. Mantovani and Pavlikova have no financial interest to disclose. Dr. Avery reports research grants, speaking fees, or advisory board work with Eli Lilly and Company, Forest Pharmaceuticals, Northstar Neuroscience, Neuronetics Inc, Performance Plus, and Takeda. Dr. Nahas reports past and current research grants, speaking fees, or consulting work with Avanir Pharmaceutical, Aventis Pharmaceutical, Cyberonics Inc, Eli Lilly and Company, Hope for Depression Research Foundation, Integra, Medtronic Inc, National Alliance of Research on Schizophrenia and Depression, National Institute of Mental Health, Neuronetics Inc, and Neuropace (unpaid consultant). Dr. McDonald has received past research funding from Neuronetics. Dr. McDonald is also an unpaid consultant for NeuroStim. Dr. McDonald is on the faculty at Emory University which holds a patent on a TMS device. He receives no payment or royalties on this device. Chandra Wajdik has no financial interest to disclose. Dr. Holtzheimer has received consulting fees from St. Jude Medical Neuromodulation. Dr. George has been an unpaid advisor to Brainsonix, Brainsway, Neuronetics, Neostim and Neosync (as they make products related to TMS), and a paid advisor to Puretech ventures. The full amount of his advisory income has never been more than 10% of his university salary. MUSC has two patent applications in Dr. George’s name on combining TMS with MRI imaging. He has no equity investment in any device or pharmaceutical company. Dr. Sackeim has served as a consultant to Cyberonics, Inc., Magstim Inc., MECTA Corp., and Neuronetics, Inc. Dr. Lisanby has served as PI on industry-sponsored research grants to Columbia/RFMH or Duke (Neuronetics (past), Brainsway, ANS/St. Jude, Cyberonics (past)); equipment loans to Columbia or Duke (Magstim, MagVenture); is co-inventor on a patent application for TMS technology not the topic of study here; and has no consultancies, speakers bureau memberships, board affiliations, or equity holdings in related industries.

© 2012 Wiley Periodicals, Inc.

Figures

Figure 1

Flow chart.