Transcranial magnetic stimulation in psychiatry: A Singapore perspective

Abstract

The use of repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder (MDD) and obsessive-compulsive disorder (OCD) has not been described in Singapore. Reports on the effectiveness of rTMS in populations outside of Western countries are also limited. Thus, Ye et al.’s study on the naturalistic outcomes of rTMS treatment is important in the Asian context.1 The lifetime prevalence of depression in Singapore is 6.3%.2 It has been estimated that 30%–60% of patients with MDD do not respond to a first-line antidepressant, whereas 40% do not respond to a second-line antidepressant. Treatment resistant depression (TRD) is a term often used when a patient has failed to respond to 2 different antidepressants, with adequate adherence for a duration of 4–8 weeks. Further trials of antidepressant medication result in diminishing response rates and prolonging illness duration.3 Options for TRD include continued trials of different medications—utilising switching, augmentation or combination approaches and using psychotherapy and/or non-invasive neurostimulation techniques, such as rTMS and electroconvulsive therapy (ECT). While ECT is recognised as the most effective non-invasive neurostimulation treatment, studies have increasingly demonstrated that rTMS is more cost effective4 and has demonstrated superiority to switching antidepressants.5 In Singapore, the College of Psychiatrists endorsed the use of rTMS for MDD in 2015 and OCD in 2018. The Institute of Mental Health (IMH) has the largest psychiatric rTMS service in Singapore.