Longitudinal PTSD Trajectories Before and After the October 7, 2023, Terror Attacks: A Nationwide Study of Israeli Adults

Background: Existing research on Post-Traumatic Stress Disorder (PTSD) development over time covers brief periods predominantly among military personnel, rather than civilians, and baseline measurements from before traumatic experiences are rarely available. This longitudinal study examined PTSD trajectories among Israeli civilians before and after the October 7, 2023 terror attack, exploring their associations with current and previous trauma. Methods: Data included 1,231 Israeli Jewish adults from a quasi-representative sample surveyed at four time points: January 2018, April 2022, December 2023, and March 2024. Participants completed self-report measures, including the PTSD Checklist for DSM-5 (PCL-5), exposure to the October 7 attack and subsequent war, and trauma in childhood and adulthood. Latent growth mixture modeling identified PTSD trajectories. Results: Four trajectories were identified: resilience (70.4%), trauma recovery (9.4%), trauma vulnerability (16.8%), and chronic PTSD (3.5%). The chronic PTSD group exhibitedpersistently high symptoms, associated with greater childhood trauma and warrelated exposure. The trauma vulnerability group showed low-medium pre-attack PTSD levels that escalated post-attack, associated with higher war-related stressors. The trauma recovery group had high pre-attack PTSD severity related to high trauma exposure but showedsignificant symptom reduction post-attack. Discussion: This study, the first to examine PTSD trajectories in civilians after large-scale trauma, highlights diverse impacts. Most participants demonstrated resilience, while some exhibited chronic symptoms. Two trajectories—trauma vulnerability and trauma recovery—were event-responsive, suggesting that collective trauma can both exacerbate and paradoxically alleviate symptoms. Findings emphasize the need for targeted interventions and suggest future research using machine learning to refine PTSD trajectory prediction.