Effects of early trauma on psychosis development in clinical high-risk individuals and stability of trauma assessment across studies: a review

Early trauma (ET), though broadly and inconsistently defined, has been repeatedly linked to numerous psychological disturbances, including various developmental stages of psychotic disorders. The prodromal phase of psychosis highlights a unique and relevant population that provides insight into the critical periods of psychosis development. As such, a relatively recent research focus on individuals at clinical high risk (CHR) for psychosis reveals robust associations of early life trauma exposures with prodromal symptoms and function in these cohorts. While prevalence rates of ET in CHR cohorts remain consistently high, methodological measures of traumatic experiences vary across studies, presenting potential problems for reliability and validity of results. This review aims to 1) highlight the existing evidence identifying associations of ET, of multiple forms, with both symptom severity and transition rates to psychosis in CHR individuals, 2) present data on the variability among trauma assessments and its implications for conclusions about its relationship with clinical variables, 3) describe cognitive deficits common in CHR cohorts, including perceptual and neurocognitive impairments, and their neural correlates, that may modify the relationship of ET to symptoms, and 4) propose future directions for standardization of trauma assessment in CHR cohorts to better understand its clinical and cognitive correlates.