Disinhibited social engagement and reactive attachment behaviours in children assessed for Fetal Alcohol Spectrum Disorder (FASD): Distinguishing effects of maltreatment from inhibitory control difficulties.

The developmental origins of reactive attachment disorder (RAD) and disinhibited social engagement disorder (DSED) continue to be poorly understood. This cross-sectional study reports on the rates of RAD and DSED behaviours in a clinical sample of children presenting for Fetal Alcohol Spectrum Disorder (FASD) assessment (N = 123). It examines whether RAD and DSED behaviours, assessed by diagnostic interview with carers, are better explained by maltreatment (timing/type) or neurodevelopmental inhibitory-control deficits, assessed using the BRIEF-2, adjusting for age, sex and variables related to care history. There were high rates of DSED and relative low rates of RAD behaviours in this sample. Neglect past 24 months of age significantly predicted the presence of DSED behaviours related to affectionate behaviour and lack of reticence with strangers, whereas neglect and removal before 24 months did not impact these behaviours. Poor inhibitory control significantly predicted most DSED behaviours, and a RAD behaviour related to dysregulated negative affect. The overlap between poor inhibitory control, which was unrelated to maltreatment exposure in this sample, and DSED and RAD behaviours highlights the risk of diagnostic confusion when assessing for these disorders in children with suspected FASD. However, the findings also emphasise that even in the presence of poor inhibitory control owing to alcohol exposure, co-occurring exposure to prolonged neglect (past 24 months) may still contribute to the presentation of DSED behaviour. Implications for diagnosis and support are discussed. Future work should determine the non-inhibitory control related mechanisms contributing to DSED and RAD in children with prenatal adversity.