Treatment of major depression with bilateral theta burst stimulation: a randomized controlled pilot trial

Current efforts to improve clinical effectiveness and utility of repetitive transcranial magnetic stimulation (rTMS) in the treatment of major depression (MD) include theta burst stimulation (TBS), a patterned form of rTMS. Here, we investigated the efficacy of bilateral TBS to the dorsolateral prefrontal cortex (dlPFC) in patients with MD in additon to ongoing medication and psychotherapy.

In this randomized-controlled trial, thirty-two patients with MD were treated for six weeks (thirty sessions) with either successively intermittent, activity enhancing TBS (iTBS) to the left and continuous, inhibiting TBS (cTBS) to the right dlPFC or with bilateral sham stimulation. Primary outcome measure was the proportion of treatment response defined as a Montgomery-Åsberg Depression Rating Scale (MADRS)≤50% compared to baseline. Secondary outcomes comprised response and remission rates of the Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI).

A larger number of responders were found in the cTBS (n=9) compared to the sham-stimulation (n=4) group (odds ratio: 3.86; Wald χ(2)=3.9, p=0.048). On secondary endpoint analysis, patient-reported outcome as assessed by the BDI, pointed towards a higher rate of remitters in the cTBS (n=6) than in the sham (n=1) group (odds ratio: 9; Wald χ(2)=3.5, p=0.061).

With regard to the pilot character of the study and the small sample size, the results have to be considered as preliminary.

These findings provide first evidence that six weeks treatment of MDD with iTBS to the left and cTBS to the right dlPFC for six weeks is safe, feasible and superior to sham stimulation applied add-on to pharmacological and psychotherapeutic treatment.