Repetitive transcranial magnetic stimulation for major depression and obsessive-compulsive disorders in Singapore.

Introduction: Repetitive transcranial magnetic stimulation (rTMS) is used for treatment-resistant major depressive disorder (MDD) and obsessive-compulsive disorder (OCD), but there are few studies on patient outcomes in Southeast Asia. In this study, we describe the clinical profile and outcome of patients with MDD and OCD treated with rTMS in Singapore.

Method: A naturalistic retrospective study of 71 patients (inpatient and outpatient) who received rTMS treatment between June 2018 and April 2023 was conducted. The depressive and obsessive outcome rating scales used were clinician-rated Montgomery-Åsberg Depression Rating Scale (MADRS), Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Clinical Global Impressions-Severity (CGI-S) and self-rated Depression Anxiety and Stress Scale-21 (DASS-21).

Results: Clinician-rated and self-rated mood and general condition improved significantly. MADRS mean score improved from 28.1 (standard deviation [SD] 7.3) to 20.7 (SD 10.1) (P<0.0001) (20.8% response rate/17% remission rate). CGI-S mean 4.6 (SD 0.8) improved to 3.3 (SD 1.2) (P<0.0001). DASS-21 total mean improved from 67.3 (SD 24.6) to 49.6 (SD 28.0) (P<0.0001). Y-BOCS mean score displayed a trend towards improvement from 30.1 (SD 7.5) to 27.2 (SD 6.9) (P=0.799). However, 44.4% of patients with OCD responded with a minimal 20% reduction in baseline Y-BOCS. Moreover, the subgroup of 35.8% of patients with less than 30 rTMS sessions had contributed disproportionately to nonresponse (85.7%). Patients who received rTMS treatment (>30 sessions) had a trend of larger improvement of MADRS score when compared to patients with (≤30 sessions) (9.4 [SD 9.7] versus 3.8 [SD 12.3] [P=0.078]).

Conclusion: Response and remission rates for MDD and OCD suggest patients have a good response to rTMS treatment. Dosing longer rTMS sessions after an acute course helps to maximise effectiveness. Further research to determine predictors of outcome and characterise clinical features of late responders to target treatment more effectively is recommended.