Impact of childhood adversity on corticolimbic volumes in youth at clinical high-risk for psychosis

Childhood adversity is among the strongest risk factors for psychosis-spectrum disorders, though the nature and specificity of the biological mechanisms underlying this association remains unclear. Previous research reveals overlaps in the volumetric alterations observed in both adversity-exposed individuals and in psychosis-spectrum populations, highlighting the possibility that deviations in corticolimbic gray matter development may be one mechanism linking adversity and psychosis. Given that childhood adversity encompasses a wide range of adverse experiences, there is also a critical need to examine whether these different types of experiences have unique effects on corticolimbic regions. This study examined the association between childhood adversity and cortical, hippocampal, and amygdalar volume in a large sample of youth at clinical-high risk (CHR) for psychosis. We utilized a novel differentiated adversity approach that distinguishes exposures along dimensions of threat (e.g., abuse) and deprivation (e.g., poverty, neglect) to test for differential associations. Participants were drawn from the North American Prodromal Longitudinal Study (NAPLS) and completed an MRI scan and a retrospective assessment of childhood adversity at baseline. We found that deprivation exposure, but not threat, was uniquely associated with smaller cortical volume and smaller right hippocampal volume in CHR youth. These associations were masked in a generalized risk model that utilized a total adversity score. The findings suggest that deprivation exposures during childhood contribute to the subtle volumetric reductions observed in clinical high-risk samples and highlight the importance of disentangling different dimensions of adversity. (C) 2019 Elsevier B.V. All rights reserved.