Treatment of depression and borderline personality disorder with 1 Hz repetitive transcranial magnetic stimulation of the orbitofrontal cortex – A pilot study

Borderline personality disorder (BPD) is characterised by impairments in emotional regulation, impulse control and interpersonal interaction. Comorbid depression is common. The orbitofrontal cortex (OFC) plays a crucial role in the biological substrate of BPD. We investigated the effects of 1 Hz repetitive transcranial magnetic stimulation (rTMS) targeting the OFC on depressive symptoms and symptoms of BPD in 15 patients suffering from both conditions to assess feasibility and effectiveness. Target treatment intensity was 120% of resting motor threshold (RMT) and intended duration four weeks. Treatment improved both symptoms of depression as measured by the Hamilton Depression Rating Scale and of BPD as measured by Borderline Symptom List-23 and Barratt Impulsivity Scale. Drop-out rates were high with 7/15 patients not completing the full course of rTMS, but only two drop-outs were related to treatment. Only a minority of patients tolerated target treatment intensity. Despite the limitations, the results suggest efficacy of treatment and welcome further research.