(PS11-C67) Rtms Augmentation of Intensive Outpatient Prolonged Exposure for Difficult-to-treat PTSD: Initial Outcomes, Acceptability, and Feasibility in a Clinical Pilot Study

Prolonged exposure therapy (PE; Foa, Hembree, Rothbaum, & Rauch 2019) is a highly efficacious treatment for posttraumatic stress disorder (PTSD).  Recent research has shown that PE can be delivered effectively in an intensive outpatient (IOP) format resulting in treatment completion in as little as two weeks, and significantly lower dropout rates than standard outpatient care (Ragsdale, Watkins, Sherrill, Zwiebach & Rothbaum, 2020). However a significant minority of participants still do not fully respond, suggesting continued room for enhancement of treatment effects. Repetitive transcranial magnetic stimulation (rTMS) is a candidate for PE augmentation, as it may enhance neuroplasticity (Wilkinson, Holtzheimer, Gao, Kirwin, & Price, 2019) and fear extinction (Borgomaneri et al., 2020), which could aid patients in leveraging the full effects of the therapy.  A recent study found that combining rTMS with outpatient cognitive processing therapy for PTSD was associated with improved outcomes compared to a sham control (Kozel et al., 2018). The current study was a clinical pilot examining the addition of rTMS to the right dorsolateral prefrontal cortex prior to daily PE sessions in a 2-week IOP for military veterans and servicemembers with PTSD. Patients who were suspected to be low- or non-responders were recommended to treatment. Those who consented received between 3 and 9 rTMS (1Hz at 110% motor threshold to right DLPFC) sessions immediately prior to their daily imaginal exposure sessions. Treatment expectancy and treatment satisfaction were collected prior to initiation of rTMS, and both patient and therapist perception of rTMS helpfulness were collected following IOP. PTSD symptoms (PTSD Checklist for DSM-5; PCL-5) and depression symptoms (Patient Health Questionnaire-9; PHQ-9) were collected at baseline, and after sessions 3, 5, 6, 8, and 10 (post-treatment). Data collection is ongoing and complete results will be reported upon presentation, however an initial analysis of an early subset of patients (n=10; demographics: 50% female, 30% black/African-American) suggested that PTSD and depression symptoms significantly reduced over the course of treatment (PCL-5: mean change = -17.20 (SD=16.24), t(9) = 3.35, p=.009; PHQ-9: mean change = -4.4 (SD=4.4), t(9) = 3.16, p=.012) with minimal dropout and few reported side effects, suggesting that the treatment was acceptable and feasible in an IOP treatment setting for diverse group of veteran patients.