Randomized controlled trial of two internet-based written therapies for world trade center workers and survivors with persistent PTSD symptoms.

Posttraumatic stress disorder (PTSD) remains prevalent among individuals exposed to the 9/11 World Trade Center (WTC) terrorist attacks. The present study compared an Internet-based, therapist-assisted psychotherapy for PTSD to an active control intervention in WTC survivors and recovery workers with WTC-related PTSD symptoms (n = 105; 75% syndromal PTSD). Participants were randomized to integrative testimonial therapy (ITT), focused on WTC-related trauma, or modified present-centered therapy (I-MPCT), each comprising 11 assigned written narratives. The primary outcome was baseline-to-post-treatment change in PTSD symptoms on the PTSD Checklist for DSM-5 (PCL-5). Secondary measures included PTSD symptom clusters, depressive/anxiety symptoms, functioning, and quality of life. A significant main effect of time was observed for the primary outcome (average "large" effect size improvement, d = 1.49). Significant and "moderate-to-large" main effects of time were also observed for all PTSD symptom clusters, depressive symptoms, quality of life, and mental health-related functioning (d range=0.62-1.33). Treatment and treatment-by-time interactions were not significant. In planned secondary analyses incorporating 3-month follow-up measures, ITT was associated with significantly greater reductions than I-MPCT in PTSD avoidance and negative alterations in cognitions and mood, anxiety, and mental health-related functioning. Both therapies significantly lowered PTSD symptoms, suggesting they may benefit hard-to-reach individuals with chronic WTC-related PTSD symptoms.

Perceived social support moderates the relation between forward-focused coping and PTSD symptoms in World Trade Center trauma survivors.

Social support and perceived ability to cope with trauma have been linked to severity of PTSD symptoms. While previous literature has highlighted the influence of trauma coping style on PTSD severity, data are lacking regarding factors that may moderate this association. Such information may help inform more personalized treatments for PTSD. Toward this end, we analyzed data from 100 treatment-seeking WTC responders and survivors with full or subthreshold World Trade Center (WTC)-related PTSD who completed measures of perceived ability to cope with trauma and perceived social support prior to treatment initiation. Correlation analyses revealed that higher forward-focused perceived ability to cope (r = -0.24) and perceived social support (r = -0.32) were each associated with lower severity of PTSD symptoms. In a multivariable regression analysis, perceived social support emerged as a significant moderator of the relation between forward-focused coping and overall PTSD symptom severity (ß = -0.36). Specifically, among individuals with higher forward-focused coping, those with higher social support had lower severity of symptoms than those with lower social support. Results suggest that interventions to bolster social support among trauma survivors with a forward-focusing coping style may help mitigate severity of PTSD symptoms in treatment-seeking trauma survivors with PTSD symptoms.

Latent cause inference during extinction learning in trauma-exposed individuals with and without PTSD.

BACKGROUND: Problems in learning that sights, sounds, or situations that were once associated with danger have become safe (extinction learning) may explain why some individuals suffer prolonged psychological distress following traumatic experiences. Although simple learning models have been unable to provide a convincing account of why this learning fails, it has recently been proposed that this may be explained by individual differences in beliefs about the causal structure of the environment. METHODS: Here, we tested two competing hypotheses as to how differences in causal inference might be related to trauma-related psychopathology, using extinction learning data collected from clinically well-characterised individuals with varying degrees of post-traumatic stress (N = 56). Model parameters describing individual differences in causal inference were related to multiple post-traumatic stress disorder (PTSD) and depression symptom dimensions via network analysis. RESULTS: Individuals with more severe PTSD were more likely to assign observations from conditioning and extinction stages to a single underlying cause. Specifically, greater re-experiencing symptom severity was associated with a lower likelihood of inferring that multiple causes were active in the environment. CONCLUSIONS: We interpret these results as providing evidence of a primary deficit in discriminative learning in participants with more severe PTSD. Specifically, a tendency to attribute a greater diversity of stimulus configurations to the same underlying cause resulted in greater uncertainty about stimulus-outcome associations, impeding learning both that certain stimuli were safe, and that certain stimuli were no longer dangerous. In the future, better understanding of the role of causal inference in trauma-related psychopathology may help refine cognitive therapies for these disorders.