Maternal postnatal depression and offspring depression at age 24 years in a UK-birth cohort: the mediating role of maternal nurturing behaviours concerning feeding, crying and sleeping

Importance: Few longitudinal studies have examined the role of maternal nurturing parenting behaviours concerning feeding, crying and sleeping in the association between maternal postnatal depression (PND) and offspring depression in adulthood. Objective: To examine the association between PND and offspring depression at age 24 years and the mediating role of maternal nurturing behaviours concerning feeding, crying and sleeping. Design: Longitudinal study of mothers and their offspring in the Avon Longitudinal Study of Parents and Children, followed up through age 24 years. Offspring ICD-10 depression diagnosis diagnosis at age 24 years was established using the Clinical Interview Schedule-Revised. Symptoms of maternal depression were measured using the Edinburgh Postnatal Depression Scale at 8 months postnatally. Maternal nurturing behaviours concerning feeding, crying and sleeping were assessed using self-reported questionnaires administered from birth to age 3 years. Results: The sample with complete data on confounders for the mediation analyses was 5,881. In the fully adjusted model, there was evidence of an indirect effect from PND to offspring depression through the combination of all parenting factors (probit regression coefficient [B]=0.038, 95%CI 0.005, 0.071); however, there was no evidence of a direct effect from early maternal PND to adult offspring depression once the indirect effect via parenting factors was accounted for (B=0.009, 95%CI -0.075, 0.093). There was evidence for specific indirect effects through maternal worries about feeding (B=0.019, 95%CI 0.003, 0.035, p=0.010) and maternal perceptions and responses to crying (B=0.018, 95%CI 0.004, 0.032, p=0.012). Analyses in a larger sample using multiple imputation led to similar results. Conclusions and Relevance: The adverse impact of PND on offspring depression in early adulthood was explained by maternal nurturing behaviours concerning feeding, crying and sleeping in early infancy. Residual confounding and measurement error are likely, limiting causal conclusions. If found to be causal, reducing worries around early maternal nurturing behaviours could be a target for interventions to reduce adverse outcomes in adult offspring of depressed mothers.