Atypical diurnal patterns of hypothalamic-pituitary-adrenal (HPA) axis activity have been observed in samples of individuals following early life adversity. A characteristic pattern arising from disrupted caregiving is a low early-morning cortisol level that changes little from morning to evening. Less well understood is the plasticity of the HPA axis in response to subsequent supportive caregiving environments. Monthly early-morning and evening cortisol levels were assessed over 12 months in a sample of 3-6-year-old foster children enrolled in a randomized trial of a family-based therapeutic intervention (N=117; intervention condition, n=57; regular foster care condition, n=60), and a community comparison group of same-aged, non-maltreated children from low-income families (n=60). Latent growth analyses revealed stable and typical diurnal (morning-to-evening) cortisol activity among non-maltreated children. Foster children in the intervention condition exhibited cortisol activity that became comparable to the non-maltreated children over the course of the study. In contrast, children in regular foster care condition exhibited increasingly flattened morning-to-evening cortisol activity over the course of the study. In sum, improvements in caregiving following early adversity appear to have the potential to reverse or prevent disruptions in HPA axis functioning.
- Foster care
- HPA axis