Functional correlates of a novel 8-factor model of PTSD in U.S. military veterans: Results from the National Health and Resilience in Veterans Study

Emerging evidence indicates that more nuanced models of posttraumatic stress disorder (PTSD) may better capture the condition's symptom structure. Recent theoretical and empirical work argue that an 8-factor model of PTSD with separate internally- (e.g. flashbacks) and externally- (e.g. trauma-cue related physiological reactivity) generated intrusive symptom clusters may advance our understanding of PTSD and its treatment and course. However, the model's functional and clinical significance still requires evaluation. To this end, we analyzed data from the National Health and Resilience in Veterans Study, a nationally representative sample of 3847 trauma-exposed U.S. military veterans. Multivariable regressions were performed to assess the relationship between clinical and functional measures and the 8 symptom clusters, as assessed using the PTSD checklist for DSM-5. Externally-generated intrusions were associated with higher odds of current depression and anxiety and worse mental, cognitive, and psychosocial functioning. Anhedonia (e.g., loss of interest in enjoyable activities) was associated with all the correlates tested, while negative affect (e.g., having strong negative feelings such as fear) was linked to all measures except depression. Avoidance was linked to lower odds of current anxiety while externalizing behaviors showed higher odds of suicidal ideation. Anxious arousal was associated with lower odds of suicidal ideation but higher odds of PTSD-related impairment/distress, while dysphoric arousal was associated with higher odds of current depression, PTSD-related impairment/distress and worse mental and cognitive functioning. Results suggest that a more nuanced 8-factor model of PTSD symptoms may help inform understanding of the clinical and functional correlates of this multi-faceted disorder.