Background: The role of high-frequency rTMS over the left cortex as an add-on strategy in the treatment of major depression is still uncertain even in patients resistant to pharmacotherapy. We had planned a large sham TMS controlled study in the acute phase with a placebo-controlled relapse-prevention phase with escitalopram. However, because a recent meta-analysis showed only a small effect size of rTMS over sham TMS in the acute treatment phase of depressed patients, we decided to make an interim analysis.
Method: In patients with medication-resistant major depression we administered in a randomised trial 15 sessions of sham-controlled rTMS over three weeks in combination with 20 mg escitalopram daily. After the last rTMS, the patients were followed for another 9 weeks on 20 mg escitalopram daily. The antidepressant effect was measured by the HAM-D(6) as primary outcome scale.
Results: A total of 45 patients with complete data were randomised so that 23 patients received sham TMS and 22 patients received active, high-frequency rTMS over the left cortex. Over the 3 weeks, the active rTMS treatment was superior to sham TMS with effect sizes on the HAM-D(6) above 0.70, which indicates not only a statistically but also a clinically significant effect. The patients had typically been through two failed antidepressant treatment attempts with non-tricyclics before inclusion in the study. Both the rTMS and escitalopram were well-tolerated.
Conclusion: High-frequency rTMS over the left cortex is an add-on strategy of clinical significance in combination with escitalopram in patients with major depression resistant to non-tricyclic antidepressants.