2026 ECNP Congress

PS03-3262

Changes in symptom networks of post-traumatic stress following a cognitive task intervention in trauma-exposed healthcare workers: a network intervention analysis

Lea Krätzig — M. Gruber, P. Rehm, H. Staub, F. Timm, S. Fischer, D. Schepers, A. Reif, E. Holmes, E.J. Leehr, J. Repple · University Hospital Frankfurt, Department of Psychiatry- Psychosomatic Medicine and Psychotherapy, Frankfurt am Main, Germany

2026 ECNP Congress

Background: Post-traumatic stress (PTS) symptoms following traumatic events carry long-term clinical consequences, with post-traumatic stress disorder (PTSD) affecting 5–12% of the population over a lifetime [1]. Conceptualizing mental disorders, such as PTSD, as systems of interacting symptoms has advanced the field. However, comparatively little is known about how PTS symptom networks change in response to active interventions. Specifically, which symptoms are directly or indirectly targeted, in what order, and how treatment effects spread within such a symptom network, remains unclear [2,3]. Aim: This study aims to improve our understanding of intervention-induced changes in PTS symptom networks by applying Network Intervention Analysis (NIA) by Blanken et al. [4] to data from a randomized controlled trial (RCT) of trauma-exposed healthcare workers in Sweden during the COVID-19 pandemic [5]. This trial used a digital Imagery Competing Task Intervention (ICTI) which specially targets only one PTS symptom – intrusive memories. Methods: The RCT compared a single guided session, followed by self-use, of a remotely delivered cognitive task intervention (i.e., ICTI; a memory cue followed by a visuospatial computer game with mental-rotation instructions) against an active attention placebo control (attentive listening to a public radio podcast of equal duration) to reduce intrusive memories of a traumatic event. The intervention significantly reduced the median number of daily intrusive memories relative to control (intervention Mdn = 1.0 [IQR = 0–3] vs. control Mdn = 5.0 [IQR = 1–17]; p < 0.0001) and resulted in fewer overall PTS symptoms at one-, three-, and six-month follow-ups [5]. For the present NIA, we use the baseline intention-to-treat sample (n = 144) and available data collected at five time points: baseline, one week, one month, three months, and six months post-intervention. At each time point, we estimate a Mixed Graphical Model including eight PTS symptoms (short version of the Posttraumatic Stress Disorder Checklist 5) as ordinal nodes and treatment allocation as a binary node within the network. Edge weights represent partial associations between variables, controlling for all other nodes. To test whether the intervention directly affects intrusions (i.e., the primarily targeted symptom), we apply the edge strength invariance test of the Network Comparison Test, comparing intervention–intrusion edge strength between baseline and one-month follow-up. Secondary analyses examine whether intervention edges with other symptoms emerge or strengthen at later follow-ups, and how symptom predictability evolves across time. Results: Analyses are currently ongoing. NIA results, including estimated networks at each time point, direct and indirect intervention effects, and changes in symptom predictability, will be presented at the conference. Based on the significant intervention effects observed in the original RCT, we anticipate that the NIA will reveal a sequential pattern of change: direct effects on intrusions emerging first, followed by broader network reorganization over subsequent months. Conclusion: These findings may provide novel insights into the temporal dynamics through which a brief cognitive task intervention focussed on a single symptom (i.e., intrusive memories) reshapes PTS symptom networks, with implications for understanding mechanisms of change in early trauma-focused and cognitive interventions.

References

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