DEEP TRANSCRANIAL MAGNETIC STIMULATION TREATMENT FOR TREATMENT-RESISTANT OBSESSIVE-COMPULSIVE DISORDER: A CASE SERIES FROM THAILAND

Abstract Background Obsessive-compulsive disorder (OCD) is a chronic neuropsychiatric disorder. The first-line treatment of OCD is either pharmacological or psychotherapy. However, the rate of treatment resistant OCD after the treatment is still high (van Roessel et al., 2023). Deep Transcranial Magnetic Stimulation (dTMS) with H-7 coil has been recently approved for resistant OCD in the USA but has not been used widely in Asia. Aims & Objectives To report case series of the first 4 patients with resistant OCD who received dTMS in Thailand. Cases All 4 patients were males and they have received at least 2 antidepressants with inadequate improvement of symptoms. The mean dose of antidepressants was 85 mg/day of fluoxetine equivalent. Three of four were taking antipsychotics (2 risperidone & 1 aripiprazole)., and two of four were taking benzodiazepine. Duration of OCD varied from 1 – 6.5 years with psychiatric comorbidity ranging from insomnia disorder to post-autoimmune encephalitis. One patient underwent electroconvulsive therapy with unsatisfactory outcomes. All patients received at least 20 sessions of FDA-approved protocol of dTMS for OCD five days a week: Frequency = 20 Hz, Duration = 2 s, Wait time = 20 s, 50 trains per session, Intensity = 60% - 100% motor threshold. All patients continued taking the medications without changing the dosages. All patients reported an improvement of clinical outcomes after dTMS, reducing the overall subjective severity of the obsessive-compulsive symptoms. Minimal, transient, but tolerable adverse effects were reported without any serious events in this case series. Discussion and Conclusion This is the first report from Thailand on using dTMS as an add-on treatment with pharmacological treatments. Subjective clinical outcomes from all patients were favorable with good safety and tolerability. References 1.van Roessel PJ, Grassi G, Aboujaoude EN, Menchó n JM, Van Ameringen M, Rodrí guez CI. Treatment- resistant OCD: Pharmacotherapies in adults. Compr Psychiatry. 2023 Jan;120:152352. doi: 10.1016/j.comppsych.2022.152352. Epub 2022 Oct 25. PMID: 36368186.