Epistemic trust and personality functioning as mediators for the association of adverse childhood experiences and posttraumatic as well as complex posttraumatic stress symptoms in adulthood

Background Adverse childhood experiences (ACEs) are associated with posttraumatic and complex posttraumatic stress disorder symptoms in adulthood (PTSD/cPTSD), as well as reduced epistemic trust (trust in the authenticity and personal relevance of interpersonally transmitted information) and impaired personality functioning. The present work aims to investigate the mediating effects of reduced epistemic trust and impaired personality functioning in the association of ACEs and PTSD/cPTSD. Method We conducted structural equation modeling (SEM) based on representative data of the German population (N = 2516). Personality functioning (OPD-SQS) was applied as mediator between ACEs (ACE) and PTSD/cPTSD (ITQ), while epistemic trust (ETMCQ) was added as predictor for OPD-SQS. TLI, CFI and RMSEA (95% CI) determined the models' fit. Results N = 831 (33.0%) participants reported at least one ACE, while n = 243 (9.7%) reported ≥4 ACEs. Fit indices were good to excellent (TLI = 0.98; CFI = 0.99; RMSEA = 0.03 (95% CI = 0.013;-0.049)). ACEs were significantly associated with PTSD (β = 0.29; p < 0.001), explaining 8% of its variance. Adding OPD-SQS as mediator increased the explained variance of PTSD to 17% while the direct association between ACEs and PTSD decreased (β = 0.16), and thus, indicating a partial mediation. The ETMCQ Conclusions We add to previous research emphasizing the critical association of ACEs and PTSD/cPTSD symptoms. Offering insights on underlying factors, we show that reduced epistemic trust and impaired personality functioning are relevant mediating factors. Since both are modifiable by psychotherapy, profound knowledge about these constructs can inspire future research on psychotherapeutic interventions and prevention.