Neuropsychological Impact of Trauma-Related Mental Illnesses: A Systematic Review of Clinically Meaningful Results.

A trauma history is present in approximately 90% of adults in the United States. Comparatively, lifetime post-traumatic stress disorder (PTSD) prevalence is only 8.3% (Kilpatrick et al. Journal of Traumatic Stress, 26, 537-547, 2013). A neuropsychological understanding of trauma is essential to effective trauma-informed assessments and treatments. Prior reviews have focused on PTSD, specific neuropsychological domains, and statistically rather than clinically significant results. The current systematic review investigated standardized test performance across neuropsychological domains in participants with trauma histories and any psychiatric diagnosis. The review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. From 2350 records, the search returned 21 eligible studies: 8 for combat trauma, 2 for childhood trauma, 2 for intimate partner violence and sexual assault, 2 for accidental trauma, 1 for refugee trauma, and 6 for unspecified trauma. Mean neuropsychological scores ranged from low to high average, with one mean verbal memory score in the borderline range. These findings diverge from reports of between-group differences or experimental task performance, which suggest greater levels of static cognitive impairment. Current results are limited by lack of distinction between trauma types in the literature, a dearth of cognitive domains examined, wide use of self-report trauma measures, and publication and outcome reporting biases. Clinical implications for assessment and rehabilitation are discussed in relation to clinical significance, state versus trait based changes, intra-individual variability, changes from pre- to post-trauma, and within-group variability in resilience. Future directions are recommended in consideration of cultural factors, prospective and follow-up designs, and psychiatric diagnosis.