The effect of repetitive transcranial magnetic stimulation (rTMS) on symptoms in obsessive compulsive disorder. A randomized, double blind, sham controlled study.

BACKGROUND: The goal of our study is to assess whether transcranial magnetic stimulation (rTMS) would facilitate the effect of antidepressant in OCD patients.

METHOD: The aim of the randomized, double-blind, sham controlled study was to compare the 2 and 4 week efficacy of the 10 sessions rTMS with sham rTMS in serotonin reuptake inhibitor resistant OCD patient. Thirty three right-handed patients were randomly assigned to either active rTMS or to sham rTMS. Active rTMS with the frequency of 1 Hz at 110% of motor threshold (MT) was administered over the left dorso-lateral prefrontal cortex. The same time schedule was used for sham administration. Thirty patients finished the study, three patients' dropped out at the beginning. Psychopathology was assessed by CGI, HAMA, Y-BOCS and BAI before the treatment, immediately after the experimental treatment, and 2 weeks after the experimental treatment by an independent reviewer.

RESULTS: Both groups improved during the study period but the treatment effect did not differ between them in any of the instruments.

CONCLUSION: Low frequency rTMS administered over the left dorso-lateral prefrontal cortex during 10 daily sessions did not differ from sham rTMS in facilitating the effect of serotonin reuptake inhibitors in OCD patients.