The Relationship Between a Hierarchical Transdiagnostic Model of Vulnerability Factors and Posttraumatic Stress Disorder Symptom Clusters

The latent structure of Post-Traumatic Stress Disorder (PTSD) symptomology is the subject of ongoing deliberation. The cognitive vulnerabilities of Negative Affect, Anxiety Sensitivity and Intolerance of Uncertainty have been shown to explain symptoms clusters in multiple anxiety and mood disorders, and may be able to offer further insight to explain PTSD symptomology. Using structural equation modelling, this study examines whether a hierarchical model consisting of the general cognitive factor of Negative Affect and the transdiagnostic risk factors of Anxiety Sensitivity and Intolerance of Uncertainty can explain variability among PTSD symptom clusters as defined by the DSM-5 and/or Dysphoria models of PTSD. Anxiety Sensitivity and Intolerance of Uncertainty were tested as mid-level factors between Negative Affect and the PTSD symptom constructs. The hierarchical model fit the data well in both the DSM-5 and Dysphoria models. Negative Affect consistently showed significant direct effects on each symptoms cluster in both models. Anxiety Sensitivity served as a significant mediator of Negative Affect for several symptom clusters in both models. Intolerance of Uncertainty was non-significant either as a direct effect or as a mediator of Negative Affect in all analyses. This study demonstrates how the hierarchical model of Negative Affect, Anxiety Sensitivity and Intolerance of Uncertainty may fit upon multiple PTSD symptom constructs and offers new directions for conceptualizing this disorder.