Adjunctive high-frequency right prefrontal repetitive transcranial magnetic stimulation (rTMS) was not effective in obsessive-compulsive disorder but improved secondary depression

Background: There is preliminary evidence that repetitive transcranial magnetic stimulation (rTMS) may be useful in obsessive-compulsive disorder (OCD) patients. Methods: Our objective was to examine efficacy of adjunctive right prefrontal high-frequency (rapid) rTMS treatment in OCD patients. 42 patients with OCD were randomly assigned to 10 sessions of add-on high-frequency right prefrontal active rTMS (10. Hz, 110% of motor threshold, 4. s per train, 20 trains per session) or sham stimulation. They were rated on Yale Brown Obsessive Compulsive Scale (YBOCS), Hamilton Rating Scale for Depression (HAM-D), Hamilton Rating Scale for Anxiety (HAM-A) and Clinical Global Impression-Severity of Illness (CGI-S) at baseline, day 14 and day 28. The dose of antiobsessive drug was kept constant throughout the period of assessment. Results: For YBOCS scores, repeated measures ANOVA showed significant main effect of treatment, but no effect of treatment over time (Pillai's Trace F=1.39, p=262). However, significant effect of treatment over time as shown by interaction effect for both HAM-D (Pillai's Trace F=3.67, p=035, η²=158) and HAM-A scores (Pillai's Trace F=5.22, p=01, η²=211) were seen. Conclusion: Adjunctive high-frequency right prefrontal rTMS does not have any significant effect in the treatment of OCD. However, it is modestly effective in the treatment of comorbid depressive symptoms in patients with OCD.