Maternal Depression Mediated the Association Between Moderate Income Inequality and Physical Aggression in Five Year Old Children

Background: Pathways linking income inequality and health have been hypothesized, with few studies identifying the role of potential mediators pertaining to children’s health. Objective: This study examined whether the association between income inequality and children’s physical aggression was mediated by maternal depression, anxiety, or social support. Methods: Data were drawn from the All Our Families (AOF) longitudinal cohort based in Calgary, Canada, was used (n=1090 mother-child dyads). Neighbourhood income inequality was measured via the Gini coefficient derived from the 2006 Canadian Census. Mothers completed the Center for Epidemiologic Scales for Depression, Spielberger State Trait Anxiety Inventory, and the Medical Outcomes Study Social Support Scales, respectively at 3 months postpartum. Maternal and child demographic characteristics were measured at 3 years postpartum. Children’s physical aggression was assessed using the Behavior Assessment System for Children, Second Edition at 5 years postpartum. Multilevel path models were used. Results: Mothers in neighbourhoods with moderate income inequality had higher depression symptoms (b=0.49, 95% CI: 0.01, 0.97) compared to mothers in the most equal neighbourhoods (low-income inequality). Maternal depression was subsequently associated with physical aggression in children (b=0.26, 95% CI: 0.04, 0.47). Maternal social support was lower (b=-2.51, 95% CI:-4.53,-0.49) among mothers in neighbourhoods with high income inequality compared to mothers in the most equal neighbourhoods. Conclusion: The association between income inequality, maternal mental health, social support, and child physical aggression is complex. More research comprising larger, diverse samples of mother-child dyads may be required to clarify these associations.