A topic model analysis of dually diagnosed Veterans' Written Exposure Therapy (WET) narratives

Written Exposure Therapy (WET) is a brief cognitive behavioral intervention that appears clinically useful for the individuals dually diagnosed with PTSD and substance use disorders. However, the factors that are associated with its effectiveness for this population are unclear. A promising direction for investigating correlates of WET treatment outcomes is to study the written narratives generated during exposure sessions.

This study analyzed the WET narratives of dually diagnosed Veterans (n = 19) as part of a larger feasibility study implementing this intervention in a residential substance use disorder treatment setting. Participants' narratives were analyzed with a structural topic modeling approach to explore latent topics that characterize the writings and examine their associations with study outcomes.

Latent topics were found to characterize WET narratives, with one appearing to comprise a dimension of negative cognitions. Change in negative cognitions in Veterans' writings over the course of treatment associated with change in PTSD symptom severity, as measured by the CAPS-5 (p = 0.045). Increasingly writing of the negative impact of the traumatic event was associated with reduced treatment response.

The results may indicate that negative cognitions common among dually diagnosed individuals may interfere with the effectiveness of WET.