Repetitive transcranial magnetic stimulation for treatment-resistant depression: a systematic review and meta-analysis

Objective: To evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in patients with major depressive disorder (MDD) and 2 or more prior antidepressant treatment failures (often referred to as treatment-resistant depression [TRD]). These patients are less likely to recover with medications alone and often consider nonpharmacologic treatments such as rTMS.

Data sources: We searched MEDLINE, EMBASE, the Cochrane Library, PsycINFO, and the International Pharmaceutical Abstracts for studies comparing rTMS with a sham-controlled treatment in TRD patients ages 18 years or older.

Study selection: We included 18 good- or fair-quality TRD studies published from January 1, 1980, through March 20, 2013.

Data extraction: We abstracted relevant data, assessed each study's internal validity, and graded strength of evidence for change in depressive severity, response rates, and remission rates.

Results: rTMS was beneficial compared with sham for all outcomes. rTMS produced a greater decrease in depressive severity (high strength of evidence), averaging a clinically meaningful decrease on the Hamilton Depression Rating Scale (HDRS) of more than 4 points compared with sham (mean decrease = -4.53; 95% CI, -6.11 to -2.96). rTMS resulted in greater response rates (high strength of evidence); those receiving rTMS were more than 3 times as likely to respond as patients receiving sham (relative risk = 3.38; 95% CI, 2.24 to 5.10). Finally, rTMS was more likely to produce remission (moderate strength of evidence); patients receiving rTMS were more than 5 times as likely to achieve remission as those receiving sham (relative risk = 5.07; 95% CI, 2.50 to 10.30). Limited evidence and variable treatment parameters prevented conclusions about which specific treatment options are more effective than others. How long these benefits persist remains unclear.

Conclusions: For MDD patients with 2 or more antidepressant treatment failures, rTMS is a reasonable, effective consideration.