Trajectories for Post-traumatic Stress Disorder Symptoms among Local Disaster Recovery Workers Following the Great East Japan Earthquake: Group-based Trajectory Modeling.

Background: As many local municipality and medical workers were involved in disaster recovery duties fol- lowing the Great East Japan Earthquake (GEJE) on March 11, 2011, the aim of this work was to elucidate the distinct trajectories for post -traumatic stress disorder (PTSD) symptoms and associated factors among these personnel. They confronted a diverse range of stressors both as survivors and as relief workers; however, little is known about their longitudinal PTSD symptoms. Methods: The participants were 745 local municipality and hospital medical workers [average age: 43.6 +/- 9.5 years, range: 20 - 66 years; 306 (59%) women] involved in disaster recovery duties following the GEJE. PTSD symptoms were measured using the Japanese version of the PTSD Checklist Specific Version (PCL-S) at four time points: 14, 30, 43, and 54 months after the GEJE. Using group -based trajectory modeling, distinct trajectories were elucidated. Results: We identified five distinct PTSD symptoms profiles: resistance (n = 467, 62.7%), subsyndromal (n = 181, 24.3%), recovery (n = 47, 6.3%), fluctuating (n = 26, 3.5%), and chronic (n = 24, 3.2%). The trajectories differed according to the post -disaster working conditions and personal disaster experiences. Limitations: Potential selection bias resulting from the limited number of participants who completed all waves. The survey was conducted in one region of the disaster area. Conclusions: The majority of participants remained stable, with a relatively small group classified as chronic and fluctuating. Our results highlight the importance of improved working conditions and sustained monitoring of workers responding to natural disasters.