Methods: We acquired diffusion-weighted MRI data from 101 adolescents with CD (52 females) and 99 controls (50 females). Data were processed for deterministic spherical deconvolution tractography. Virtual dissections of the UF, the three subdivisions of the cingulum (retrosplenial, parahippocampal and subgenual cingulum), and the fornix were performed and measures of fractional anisotropy (FA) and hindrance-modulated orientational anisotropy (HMOA) were analysed.
Results: The CD group had lower FA and HMOA in the right retrosplenial cingulum tract relative to controls. Importantly, these effects were moderated by sex - males with CD significantly lower FA compared to male controls, whereas CD and control females did not differ.
Conclusions: Our results highlight the importance of considering sex when studying the neurobiological basis of CD. Sex differences in retrosplenial cingulum connectivity may contribute to sex differences in the clinical presentation of CD.