Peritraumatic Dissociation Partially Mediates the Influence of Lifetime Trauma Exposure on Prospective PTSD Symptoms.

Higher lifetime trauma exposure and increased peritraumatic dissociation (PD) are well-known predictors of Post-Traumatic Stress Disorder (PTSD) symptoms following new trauma (prospective PTSD symptoms). The interplay between those factors, however, is not well established. In this study, we aimed to assess whether PD mediates the influence of lifetime trauma exposure on prospective PTSD symptoms. A total of 387 adults visiting five emergency departments who had experienced a traumatic event within 72 hours completed baseline assessments on lifetime trauma exposure count and PD. PTSD symptoms were assessed 1 month later. Structural equation modeling was used to examine the mediation effect of PD in the relationship between lifetime trauma exposure count and 1-month PTSD symptoms. We found that PD mediated the association between lifetime trauma exposure count and 1-month PTSD symptoms, even after accounting for some confounders. However, the mediation was partial, accounting for 17.9% of the lifetime trauma exposure count's total effect. While this finding is significant, it also suggests that additional mechanisms beyond PD play a role in explaining the influence of higher lifetime trauma exposure on prospective PTSD symptoms. These findings provide valuable insights into the complex dynamics of PTSD development and call for further research to explore complementary factors and preventive strategies.