Longitudinal network structures in PTSD treatment outcomes: Implications for tailored treatment

Post-traumatic Stress Disorder (PTSD) is a debilitating condition disproportionately affecting military populations. Despite wide-spread availability of trauma-focused treatments like Cognitive Processing Therapy (CPT) and Prolonged Exposure Therapy (PE), many patients continue to experience PTSD symptoms post-treatment. This study employed network analyses to investigate variations in PTSD symptom networks between treatment responders and non-responders. The sample comprised 1902 service members and veterans who completed a two-week intensive PTSD treatment program (CPT or PE). The PTSD Checklist for DSM-5 assessed baseline and post-treatment PTSD severity. Most participants were male (80.27 %), White (76.17 %), veterans (76.37 %), and previously deployed (90.13 %). We compared networks across groups at baseline and within groups over treatment. Participants reported significant declines in PTSD severity over time (t[11901] = 1238.13, p < 0.001), with 28.23 % (n = 537) classified as responders based on a reliable change index. Responders had significantly higher baseline PTSD severity than non-responders (t([11,393.9] = -14.29, p < 0.001). Network comparison tests revealed a higher global strength among non-responders at baseline. Network structure and connectivity remained stable from baseline to post-treatment, suggesting limited reorganization of symptom relationships during the initial two-week treatment phase. Slope analysis revealed lower network connectivity among responders, indicating a loosening symptom interrelations potentially linked to greater symptom independence or reduced mutual reinforcement. A reduction in global strength and significant structural differences were identified between post-treatment and 12-month follow-up networks. Reductions in central symptoms identified in slope network might serve a key role in monitoring treatment response. Follow-up network revealed structural changes that might reflect skill application after treatment.