# The moderating role of hippocampal volume in the association between emotional abuse and peer victimization in adolescents with major depressive disorder

## TL;DR

This study explores how hippocampal volume influences the link between childhood emotional abuse and adolescent peer victimization in teens with depression.

## Contribution

The study identifies hippocampal volume as a moderator in the relationship between emotional abuse and peer victimization in adolescents with MDD.

## Key findings

- Emotional abuse is significantly correlated with peer victimization in adolescents with MDD.
- Bilateral hippocampal volume moderates the relationship between emotional abuse and peer victimization.
- Larger hippocampal volumes are associated with a stronger link between emotional abuse and peer victimization.

## Abstract

Given its vicious cycle of victimization, early life adversity (ELA) in childhood may be associated with peer victimization during adolescence. Both ELA and peer victimization have been suggested to be major risk factors for depression. Volumetric alterations in the hippocampus implicated in stress sensitivity have been reported in individuals with ELA and peer victimization. This cross-sectional study examined the moderating role of hippocampal volume in the association between ELA and peer victimization in adolescents with major depressive disorder (MDD). The sample included 78 adolescents with MDD (age M (SD) = 14.92 (1.54) years, 56 females). The Early Trauma Inventory-Short Form and Peer Victimization Scale were used to assess participants’ ELA and peer victimization, respectively. High-resolution structural T1 images were obtained using a Siemens 3T magnetic resonance scanner. Whole hippocampal volumes were segmented and calculated using the FreeSurfer 6.0. Correlation and moderation analyses were also performed. Emotional abuse, a type of ELA, was significantly correlated with peer victimization after controlling for age and sex. The association between emotional abuse and peer victimization was moderated by bilateral hippocampal volume in adolescents with MDD after controlling for age, sex, and intracranial volume. Additionally, the association between emotional abuse and peer victimization was stronger when the bilateral hippocampal volumes were larger. Our findings partially supported the concept of a vicious cycle of victimization, which may be a critical aspect of depression in adolescents. Furthermore, the moderation results suggested that hippocampal volume plays an important role in the victimization cycle in adolescents with MDD.

The online version contains supplementary material available at 10.1007/s00787-025-02737-2.