Dorsomedial prefrontal rTMS for depression in borderline personality disorder: A pilot randomized crossover trial
Feffer K., Lee HH., Wu W., Etkin A., Demchenko I., Cairo T., Mazza F., Fettes P., Mansouri F., Bhui K., Daskalakis ZJ., Blumberger DM., Giacobbe P., Downar J.
Background: Recently, a small literature has emerged suggesting that repetitive transcranial magnetic stimulation (rTMS) may offer benefit for MDD even in BPD patients, perhaps by enhancing cognitive control, and/or disrupting excessive ‘non-reward’ activity in right orbitofrontal regions. This study aimed primarily to assess the therapeutic effects of dorsomedial prefrontal cortex (DMPFC)-rTMS against MDD symptoms in BPD patients, and secondarily to assess whether the therapeutic effects ensued via mechanisms of reduced impulsivity and core BPD pathology on clinical scales (BIS-11, ZAN-BPD) or of reduced alpha- and theta-band activity on EEG recordings of right orbitofrontal cortex. Methods: In a crossover-design trial, 20 BPD patients with MDD underwent 2 × 30 session/15 day blocks of either active-then-sham or sham-then-active bilateral 20 Hz DMPFC-rTMS. Results: Sixteen out of 20 patients completed treatment. A significant (p = 0.00764) crossover effect was detected, with overall reductions in HamD17 score from 23.1±SD3.1 to 10.75±SD5.8. Nine out of 16 (56.3%) treatment completers achieved response (>50% improvement) and 6/16 (37.5%) achieved remission (HamD≤7), maintained at 1 month followup. BIS-11 scores remained unchanged, and ZAN-BPD scores improved similarly in both groups with no significant crossover effect. Change in low-band power over right orbitofrontal regions correlated with clinical improvement. Limitations: This was a crossover study with a small sample size. A randomized controlled trial with larger sample size will be needed to establish the efficacy more definitively. Conclusions: The results suggest efficacy for DMPFC-rTMS in treating MDD in BPD, and provide a foundation for a larger future trial.