5 Hz Repetitive transcranial magnetic stimulation for posttraumatic stress disorder comorbid with major depressive disorder.

Background: Standard clinical protocols for repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder (MDD) apply 10 Hz pulses over left prefrontal cortex, yet little is known about the effects of rTMS in more diagnostically complex depressed patients.

Objective/hypothesis: Posttraumatic stress disorder (PTSD) is commonly comorbid with MDD, and while rTMS has been shown to alleviate PTSD symptoms in preliminary studies, ideal parameters remain unclear. We conducted a prospective, open-label study of 5 Hz rTMS for patients with comorbid PTSD + MDD and hypothesized stimulation would reduce symptoms of both disorders.

Methods: Outpatients (N = 40) with PTSD + MDD and at least moderate global severity were enrolled. 5 Hz rTMS included up to 40 daily sessions followed by a 5-session taper. Symptoms were measured using the PTSD Checklist (PCL-5) and Inventory of Depressive Symptomatology, Self-Report (IDS-SR). Baseline-to-endpoint changes were analyzed.

Results: The intent-to-treat population included 35 participants. Stimulation significantly reduced PTSD symptoms (PCL-5 baseline mean ± SD score 52.2 ± 13.1 versus endpoint 34.0 ± 21.6; p < .001); 23 patients (48.6%) met a pre-defined categorical PTSD response criteria. MDD symptoms also improved significantly (IDS-SR, baseline 47.8 ± 11.9 to endpoint 30.9 ± 18.9; p < .001); 15 patients (42.9%) demonstrated categorical response and 12 (34.3%) remitted. PTSD and MDD symptom change was highly correlated (r = 0.91, p < .001).

Limitations: Unblinded single-arm study, with modest sample size.

Conclusion: Significant and clinically meaningful reductions in both MDD and PTSD symptoms were observed following stimulation. The preliminary efficacy of 5 Hz rTMS for both symptom domains in patients with comorbid disorders supports future controlled studies.