Clinical significance of novel 8-factor model of DSM-5 PTSD in national VA PTSD residential treatment data: Internally- v. externally-cued intrusions

Background: Intrusion symptoms are a core defining feature of posttraumatic stress disorder (PTSD). It was recently proposed that intrusions may be comprised of two distinct underlying processes: internally-cued intrusions (e.g., trauma-related memories), and externally-cued intrusions (e.g., reactivity to trauma-related cues in one's environment). This is the first study to examine the functional correlates of these two intrusion clusters. Methods: Participants included 7460 veterans discharged from 40 Veterans Affairs PTSD residential programs across the United States in fiscal years 2018 through 2020. Latent network modeling and structural equation modeling were used to assess the fit of an 8-factor model of PTSD symptoms, which were assessed using the PTSD Checklist for DSM-5 (PCL-5) PTSD symptoms at admission, and its association with symptoms of depression and generalized anxiety, and emotional and physical functioning. Results: The 8-factor model, with separate intrusion factors, showed superior model fit to the DSM-5 4-factor, 5-factor dysphoric arousal, 6-factor anhedonia, and 7-factor hybrid models of PTSD. Internally-cued intrusions were uniquely associated with dysphoric arousal, decreased avoidance, and worse physical health functioning; whereas, externally-cued intrusions were uniquely associated with greater avoidance, anxious arousal, negative affect, increased generalized anxiety symptoms, and worse emotional functioning. Limitations: Limitations include the cross-sectional design and use of self-report measures. Conclusions: Findings provide initial support for the clinical utility of a novel 8-factor model of PCL-5 PTSD symptoms, which distinguishes internally- and externally-cued intrusions. These separate intrusion symptom clusters may offer greater specificity and utility in informing the prognosis of and tailored interventions for PTSD.