Repetitive transcranial magnetic stimulation improves consciousness in some patients with disorders of consciousness

Abstract

Objective

To investigate the therapeutic efficacy of repetitive transcranial magnetic stimulation (rTMS) in patients with disorders of consciousness.

Design and Setting

We performed a randomized, double-blinded, sham-controlled trial.

Participants

Patients (N = 40) with disorders of consciousness.

Interventions

Forty patients with disorders of consciousness (time since onset of the disorder 49.0 ± 24.6 days) were enrolled and randomized to groups receiving either active-rTMS or sham-rTMS. The active-TMS protocol had a frequency of 20 Hz, was delivered over the left dorsolateral prefrontal cortex and had a 100% rest motor threshold. The sham-rTMS protocol was the same as the active protocol without magnetic stimulation over the cortex.

Main Outcome Measures

Consciousness was evaluated by the Coma Recovery Scale-Revised (CRS-R) before and after the four-week intervention. The ratio of patients that awakened from disorders of consciousness was followed up at discharge.

Results

Before rTMS sessions, there were no significant differences in consciousness scores between groups. Compared to sham-rTMS (6.25 ± 1.29), patients with disorders of consciousness treated by active rTMS showed strikingly improved consciousness (8.45 ± 3.55). In-depth analysis revealed that only some patients showed obvious increases in consciousness scores induced by active rTMS. Furthermore, rTMS did not significantly enhance the awakening ratio.

Conclusions

rTMS showed therapeutic efficacy for improving consciousness in some, but not all, patients with disorders of consciousness. It is essential to discern the potential patients whose consciousness can be improved by rTMS.