Low-frequency repetitive transcranial magnetic stimulation (rTMS) over the right dorsolateral prefrontal cortex (DLPFC) in generalized anxiety disorder (GAD)

Publication Reference

Diefenbach, G., Bragdon, L., Zertuche, L., Hyatt, C., Hallion, L., Tolin, D., Goethe, J. and Assaf, M. (2016). Repetitive transcranial magnetic stimulation for generalised anxiety disorder: A pilot randomised, double-blind, sham-controlled trial. British Journal of Psychiatry209(03), 222-228.

 

Article Summary*

In this small, randomized, double-blind, sham-controlled study, the authors examined the impact of 30 sessions of low-frequency (1 Hz) rTMS over the right DLPFC in treating GAD. Response at post-treatment and 3-months follow-up were assessed using the Clinical Global Impression – Severity Scale and the Hamilton Rating Scale for Anxiety. At immediate post-treatment follow-up, significantly more patients met response criteria in the active rTMS group (8/13; 61.5%) verses the sham-control group (2/12; 16.7%). Further, more patients were classed as remitters in the active rTMS group (4/13; 30.8%) versus the sham group (1/12; 8.3%), although this did not reach statistical significance. At 3-months follow-up, significantly more patients in active rTMS were classed as responders (8/13; 61.5%) and remitters (7/13; 53.8%) compared to sham treatment (0/12 responders or remitters). During an emotional regulation task, functional magnetic resonance imaging (fMRI) showed that there was a significant post-treatment increase in right DLPFC activity in the active rTMS group, whilst the sham group showed a decrease in activity.  Moreover, active rTMS-related increases in right DLPFC activity were correlated with improved anxiety symptoms, particularly those related to worry. Changes in right DLPFC activity were not associated with changes in depressive symptoms. The authors discuss potential reasons as to why inhibitory low-frequency rTMS may lead to increases in right DLPFC activity, and how this may relate to emotional regulation.

 

*For original abstract/publication see the link below.

 

Publication link: Repetitive transcranial magnetic stimulation for generalised anxiety disorder: A pilot randomised, double-blind, sham-controlled trial | The British Journal of Psychiatry | Cambridge Core