Background: Effectiveness of repetitive transcranial magnetic stimulation (rTMS) for major depression is unclear. The authors performed a randomized controlled trial comparing real and sham adjunctive rTMS with 4-month follow-up.
Method: Fifty-nine patients with major depression were randomly assigned to a 10-day course of either real (n=29) or sham (n=30) rTMS of the left dorsolateral prefrontal cortex (DLPFC). Primary outcome measures were the 17-item Hamilton Depression Rating Scale (HAMD) and proportions of patients meeting criteria for response (50% reduction in HAMD) and remission (HAMD8) after treatment. Secondary outcomes included mood self-ratings on Beck Depression Inventory-II and visual analogue mood scales, Brief Psychiatric Rating Scale (BPRS) score, and both self-reported and observer-rated cognitive changes. Patients had 6-week and 4-month follow-ups.
Results: Overall, Hamilton Depression Rating Scale (HAMD) scores were modestly reduced in both groups but with no significant groupxtime interaction (p=0.09) or group main effect (p=0.85); the mean difference in HAMD change scores was -0.3 (95% CI -3.4 to 2.8). At end-of-treatment time-point, 32% of the real group were responders compared with 10% of the sham group (p=0.06); 25% of the real group met the remission criterion compared with 10% of the sham group (p=0.2); the mean difference in HAMD change scores was 2.9 (95% CI -0.7 to 6.5). There were no significant differences between the two groups on any secondary outcome measures. Blinding was difficult to maintain for both patients and raters.
Conclusions: Adjunctive rTMS of the left DLPFC could not be shown to be more effective than sham rTMS for treating depression.