Testing the ecophenotype model: cortical structure alterations in conduct disorder with versus without childhood maltreatment

BACKGROUND Childhood maltreatment is common in youths with Conduct Disorder (CD) and both CD and maltreatment have been linked to neuroanatomical alterations. Nonetheless, our understanding of the contribution of maltreatment to the neuroanatomical alterations observed in CD remains limited. We tested the applicability of the ‘ecophenotype’ model to CD, which holds that maltreatment-related psychopathology is (neurobiologically) distinct from psychopathology without maltreatment.

METHODS Surface-based morphometry was used to investigate cortical volume, thickness, surface area and gyrification in a mixed-sex sample of CD participants (n=114) and healthy controls (n=146), aged 9–18 years. Using vertex-wise general linear models adjusted for sex, age, total intracranial volume, and site, controls were compared with the overall CD group, and the CD subgroups with (n=49) versus without (n=65) maltreatment (assessed by the Children’s Bad Experiences interview). These subgroups were also directly compared.

RESULTS The overall CD group showed lower cortical thickness in the right inferior frontal gyrus. Maltreated CD youths showed more widespread structural alterations relative to controls, comprising lower thickness, volume and gyrification in inferior and middle frontal regions. Conversely, non-maltreated CD youths only showed greater left superior temporal gyrus folding relative to controls. When contrasting the CD subgroups, those with maltreatment displayed lower right superior temporal gyrus volume, right precentral gyrus surface area, and gyrification in frontal, temporal, and parietal regions.

CONCLUSIONS Consistent with the ‘ecophenotype’ model, findings indicated that CD youths with versus without maltreatment differ neurobiologically. This highlights the importance of considering maltreatment history in neuroimaging studies of CD and other disorders.