Abstract
This study examined whether the presence of comorbid Obsessive-Compulsive Disorder (OCD) moderates the antidepressant effects of Transcranial Magnetic Stimulation (TMS) in individuals with Major Depressive Disorder (MDD). A retrospective analysis was conducted on 218 patients treated with TMS, comparing outcomes between those with MDD only (n = 182) and those with comorbid MDD and OCD (n = 36). Depression symptoms were assessed weekly using the Quick Inventory of Depressive Symptomatology-Self Report. Results indicated that both groups experienced significant reductions in depressive symptoms over time. However, participants with MDD-only showed greater symptom improvement (η² = .512) than those with comorbid OCD (η² = .177). While response rates did not significantly differ by diagnostic group, younger age and female sex were associated with greater symptom reduction. Notably, younger women with MDD showed the strongest response, while older men with comorbid OCD showed the weakest. These findings suggest that TMS is effective for reducing depressive symptoms in patients with and without OCD, but that age and sex may be stronger moderators of treatment response than diagnostic status alone. Future research should further investigate individualized treatment strategies based on demographic and clinical profiles.