Childhood maltreatment and the structural development of hippocampus across childhood and adolescence.

Background: Prior studies suggest that childhood maltreatment is associated with altered hippocampal volume. However, longitudinal studies are currently scarce, making it difficult to determine how alterations in hippocampal volume evolve over time. The current study examined the relationship between childhood maltreatment and hippocampal volumetric development across childhood and adolescence in a community sample.

Methods: In this longitudinal study, a community sample of 795 participants underwent brain magnetic resonance imaging (MRI) in three waves spanning ages 6-21 years. Childhood maltreatment was assessed using parent-report and children´s self-report at baseline (6-12 years old). Mixed models were used to examine the relationship between childhood maltreatment and hippocampal volume across time.

Results: The quadratic term of age was significantly associated with both right and left hippocampal volume development. High exposure to childhood maltreatment was associated with reduced offset of right hippocampal volume and persistent reduced volume throughout adolescence.Critically, the relationship between childhood maltreatment and reduced right hippocampal volume remained significant after adjusting for the presence of any depressive disorder during late childhood and adolescence and hippocampal volume polygenic risk scores. Time-by-CM and Sex-by-CM interactions were not statistically significant.

Conclusions: The present study showed that childhood maltreatment is associated with persistent reduction of hippocampal volume in children and adolescents, even after adjusting for the presence of major depressive disorder and genetic determinants of hippocampal structure.