Maternal health and child health disparities among Indigenous and non-Indigenous Australian children: Insights from repeated measures across infancy and adolescence

This study investigates the prevalence and predictors of inferior or less-optimal health (LOPTH) and the Physical Health Outcome Index (PHOIND) among Indigenous and non-Indigenous Australian children from infancy to adolescence, focusing on the impact of maternal health factors. Data from the Longitudinal Study of Australian Children (LSAC) (Wave 1, 2004; Wave 8, 2018) were analyzed using binary logistic and linear regression models. Bootstrap resampling was employed to address the small Indigenous sample size, and multicollinearity was assessed using variance inflation factors (VIF), generalized VIF, tolerance, and eigenvalues. Indigenous infants had a higher prevalence of LOPTH (21.5%) compared to non-Indigenous infants (12.7%), with disparities widening in adolescence (Indigenous: 27.0%; non-Indigenous: 14.9%). Maternal smoking during pregnancy significantly increased the odds of LOPTH among Indigenous infants (OR = 3.91, 95% CI: 1.33, 11.49). Maternal physical activity was associated with reduced odds of LOPTH and higher PHOIND scores, indicating protective effects. Maternal psychological distress and stressful life events (SLEs) were linked to lower PHOIND scores in Indigenous infants but not in non-Indigenous infants. Maternal LOPTH significantly impacted non-Indigenous infants' and adolescents' health but was not significant for Indigenous groups, despite Indigenous infants had nearly twice the LOPTH rate, a trend that continued into adolescence. Persistent disparities between Indigenous and non-Indigenous children are evident, highlighting the impact of maternal health. Culturally tailored interventions addressing maternal mental health, smoking, and physical activity are crucial to reduce inequities and improve health outcomes for Indigenous families in Australia. • Indigenous children face nearly double the rates of inferior or less-optimal health (LOPTH). • Maternal LOPTH significantly affects health outcomes in non-Indigenous infants. • Exercise and diet help both groups, but smoking harms Indigenous infants more. • Indigenous infants are more negatively impacted by maternal mental health issues. • Bootstrap resampling improved estimate stability in small Indigenous samples, underscoring the need for larger studies.