A prospective, double-blind, placebo sham-controlled study by researchers from Baylor College of Medicine found that patients with a higher symptom severity of obsessive compulsive disorder (OCD) were more likely to respond to deep transcranial magnetic stimulation (dTMS). The results were published in the Journal of Psychiatric Research.
Patients (N=100) with primary OCD were recruited at 11 sites between 2014 and 2017 for this study. Patients were randomized to receive 29 dTMS treatments over 6 weeks (5 per week for 5 weeks and 4 during week 6) or a sham treatment. The dTMS had an H shaped coil design which stimulated the dorsal medial prefrontal cortex (mPFC)-anterior cingulate cortex (ACC) bilaterally. The treatment group received 50 trains and 2000 pulses (20 Hz) per session in which the pulse trains were 2 seconds with a 20 second inter-train interval.
Patients were 84% White, 59% men, and aged mean 39 years. OCD symptoms were moderate to severe (57%), moderate (35%), and severe (7%).
At treatment conclusion, the model which incorporated fixed and random effects for dTMS therapy on OCD symptom reduction was significant (c2, 136.72; P <.001) but was outperformed by a model which included moderators (c2, 50.54; P =.001). Significant cofactors associated with more rapid symptom reduction included older age (d, -0.62; P =.005), lower baseline OCD severity (d, 0.50; P =.023), and lower baseline disability (d, 0.47; P =.034).
The significant moderator was the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS; d, -0.54; P =.017), in which patients in the treatment group reported a 6.3 Y-BOCS reduction and patients in the sham group, a 4.4-point reduction. Among patients who a Y-BOCS score of ³28 points at baseline, they reported a 5.9-point reduction in the treatment cohort and 2.0 point reduction in the sham group.
At 4-weeks post treatment, the fixed and random effects model (c2, 156.88; P <.001) outperformed the model which included moderators (c2, 32.72; P =.11). Only baseline severity remained significant (d, -0.45; P =.042), although older age was trending toward significance (d, -0.43; P =.051).
The baseline Y-BOCS score remained significant at 4 weeks, in which those with a baseline ³28 points (d, -0.67; P =.047) reported a 7.1-point reduction in the treatment arm and 2.9-point reduction in the sham arm.
The major limitation of this study was the lack of diversity among its participants, making it unclear whether these results may be generalizable.
These findings suggested that bilateral dTMS stimulation of the mPFC/ACC may be effective for the treatment of patients with increased symptom severity. Patients with lower OCD severity would likely benefit more from other therapeutics.
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
Storch EA, Tendler A, Schneider SC, Guzick AG, La Buissonniere-Ariza V, Goodman WK. Moderators and predictors of response to deep transcranial magnetic stimulation for obsessive-compulsive disorder. J Psychiatr Res. 2020;S0022-3956(20)31026-8. doi:10.1016/j.jpsychires.2020.10.023