Effects of a prevention program for divorced families on youth cortisol reactivity 15 years later

Abstract

Objective: We examined whether an empirically based, randomised controlled trial of a preventive intervention for divorced mothers and children had a long-term impact on offspring cortisol regulation.

Design: Divorced mothers and children (age 9-12) were randomly assigned to a literature control condition or the 11-week New Beginnings Program, a family-focused group preventive intervention for mothers and children in newly divorced families.

Main outcome measures: Fifteen years after the trial, offspring salivary cortisol (n = 161) was measured before and after a social stress task.

Results: Multilevel mixed models were used to predict cortisol from internalizing symptoms, externalizing symptoms, group assignment and potential moderators of intervention effects. Across the sample, higher externalizing symptoms were associated with lower cortisol reactivity. There was a significant group-by-age interaction such that older offspring in the control group had higher reactivity relative to the intervention group, and younger offspring in the control group exhibited a decline across the task relative to younger offspring in the intervention group.

Conclusions: Preventive interventions for youth from divorced families may have a long-term impact on cortisol reactivity to stress. Results highlight the importance of examining moderators of program effects.

Trial registration: ClinicalTrials.gov NCT01407120.

Keywords: cortisol; externalizing; intervention; parental divorce.

Figures

Figure 1

Flow of study participants

Figure 2

Cortisol reactivity by externalizing symptoms (“ext”) Note: Covariates = time of day and sex. Externalizing symptoms was analyzed as a continuous variable but set to one SD above and below the mean for display purposes. Predicted log-transformed cortisol values were subjected to anti-log-transformation in order to display cortisol values in an interpretable metric

Figure 3

Intervention × age effects on cortisol reactivity; comparison of New Beginnings Program (NBP) to the literature control condition (LC). Note: Age groupings represent median split. Covariates = time of day, sex, and externalizing symptoms. Predicted log-transformed cortisol values were subjected to anti-log-transformation in order to display cortisol values in an interpretable metric.