Feasibility, tolerability, and preliminary effectiveness of an accelerated bilateral intermittent theta-burst stimulation protocol in adults with posttraumatic stress disorder and comorbid depressive disorder following mild traumatic brain injury.

Posttraumatic stress disorder (PTSD), depressive disorder, and persistent post-concussive symptoms commonly co-occur after mild traumatic brain injury (TBI). Evidence is limited for accelerated bilateral intermittent theta-burst stimulation (AB-iTBS) in outpatient care for this triad. Single-site retrospective cohort of 64 AB-iTBS courses in 55 adults (aged 18-69; 52.7% female) with PTSD, depressive disorder, and predominantly mild TBI (2023-2026). The protocol delivered 20 sessions/day for 4 days (80/course), alternating left and right dorsolateral prefrontal cortex at 120% resting motor threshold (600-pulse theta-burst). Outcomes were feasibility, tolerability, and within-patient change in PHQ-9, PCL-5, GAD-7, and PSS at Post-treatment and Follow-up. 55/64 courses (85.9%; 95% CI, 75.0-93.4) completed; no treatment-emergent adverse events (0/64; 95% CI, 0.0-5.6). Baseline-to-Follow-up reductions were significant for PHQ-9 (dz = -0.60; p = .004), PCL-5 (dz = -0.54; p = .008), GAD-7 (dz = -0.77; p < .001), and PSS (dz = -0.67; p = .002). At Follow-up, response was 35.7% (PHQ-9), 50.0% (PCL-5), and 44.4% (GAD-7); remission was 35.0%, 33.3%, and 44.4%. Overall improvement increased from Post-treatment to Follow-up; 20.0%-28.6% first met criterion at Follow-up. AB-iTBS protocol was feasible, tolerated without documented adverse events, and associated with short-term improvement across depressive, posttraumatic, anxiety, and perceived-stress domains.