Parenting Intervention in Infancy Affects Stress Response Systems in Middle Childhood

Introduction: Regulation of the physiological stress response systems has important implications for mental and physical health (and thus for health equity), but has not been studied extensively in prevention research. There is evidence that early caregiving affects the development of the stress response systems (Gunnar, 2000). The present study investigates the impact of an evidence-based parenting intervention administered in infancy on children’s physiological regulation eight years later. We hypothesized that the active intervention would be associated with lower physiological stress and better physiological recovery than the control intervention.

Method: Participants were 96 children in middle childhood (M = 9.48 years old, SD = 0.34; 52% male) and their parents enrolled in a longitudinal study on the efficacy of the ten-session home-based intervention called Attachment and Biobehavioral Catch-up (ABC) that targets parental sensitivity.

When children were infants, families were referred to the study by Child Protective Services due to maltreatment. Families were randomized to receive either ABC or a control intervention (Developmental Education for Families; DEF). When children were 9-year-olds, physiological data were collected during a three-part parent-child interaction. Dyads completed a three-minute paced breathing baseline, then an eight-minute emotionally distressing discussion, and concluded with a five-minute positive event discussion. Each individual’s heart rate, respiratory sinus arrhythmia (RSA), and skin conductance level (SCL) were recorded continuously and averaged for each of the three parts of the interaction.

Results: Repeated-measures analyses of variance (ANOVAs) revealed main effects of the ABC intervention on children’s heart rate and RSA. Children of parents who received ABC exhibited lower heart rate (F(1,79) = 7.34, p = .008, partial η² = .09) and higher RSA (F(1,77) = 14.42, p < .001, partial η² = .16) throughout the three-part interaction than children of parents who received DEF. Children who received ABC also had marginally greater RSA reactivity than children who received DEF (F(1,93.49) = 3.39, p = .06, partial η² = .04). No significant intervention effects on SCL were detected.

Conclusion: The present study highlights that the developing stress response systems are sensitive to changes in the early caregiving environment. In particular, children whose parents received ABC exhibited lower levels of physiological stress and more adaptive flexibility than children whose parents had received a control intervention. These results suggest a promising avenue to promoting mental and physical health equity by increasing positive parenting for families experiencing challenges.