title: Pathways to inequalities in child mental health
Creators: name: Rutherford, Callum
Publisher: name: University of Liverpool Repository
Year: 2023

description: Introduction: Increasingly, there is worldwide concern at the growing incidence of mental health problems in children and young people. Poorer childhood socioeconomic conditions (SECs) have been repeatedly linked with worse mental health outcomes in later life. Reducing inequalities in child mental health is a public health priority, yet in the UK and internationally, current policies are having limited success. Recently, more emphasis has been placed on the need for prevention and early intervention to reduce health inequalities, but there are gaps in the evidence base. This thesis aims to extend our current understanding by assessing when and how socioeconomic inequalities in child mental health outcomes develop, in order to inform more effective policies and timely intervention. Methods: Study 1 is a systematic review of longitudinal studies assessing the relationship between childhood SECs around the time of birth and subsequent child mental health in the preschool period in high income countries. In subsequent studies, I analysed data from the Wirral Child Health and Development Study (WCHADS), a longitudinal cohort study of children’s mental health following 1233 children born on the Wirral, in the North-West of England. For the first time, I analysed WCHADS data using a health equity perspective to explore the relationship between childhood socioeconomic conditions (SECs) and subsequent child mental health outcomes using a variety of analytical techniques. Study 2 assesses the impact of childhood socioeconomic conditions (SECs), as measured by household income, on early life longitudinal trajectories of mental health outcomes from ages 3.5 to 9 years in a birth cohort of 760 children, using linear mixed effects models. Study 3 presents results from an analysis exploring the role of perinatal maternal mental health problems in explaining early social inequalities in child mental health outcomes at five years of age using hierarchal regression models and mediation analysis. Results: The systematic review identified that 82% of measures of childhood SECs utilised across 15 longitudinal studies were associated with mental health problems in preschool children, whereby the most disadvantaged children had poorer mental health outcomes. These findings build on current knowledge by showing that social inequalities are already established in a preschool aged population. Secondly, analysis of the WCHADS data in study two found that whilst scores for both externalising and internalising behaviour problems decreased from 3.5 to 9 years of age, indicating improving outcomes over this period, the rate of improvement was slower for disadvantaged children, with increasing inequalities observed up to age 9 years. Thirdly, analysis of WCHADS identified significant socioeconomic inequalities in externalising behaviour problems at age 5 years, measured on the basis of maternal income, whereby the most disadvantaged children scored 45 percentage points higher compared to the least disadvantaged children. This association was partially mediated by maternal mental health with pre- and post-natal maternal depressive symptomology attenuating the socioeconomic gap by 42%. Conclusions: Disadvantaged children have poorer mental health outcomes compared to more advantaged children even in the preschool period. This thesis has demonstrated that the relationship between SECs at birth and child mental health outcomes is evident in the early years in high-income countries, and also in the Wirral population. For children in the WCHADS study, socioeconomic inequalities in mental health outcomes emerge after the age of three and increase up to the age of nine. Inequalities in early externalising problems are partially explained by perinatal maternal mental health problems. Polices to reduce inequalities should focus on improving SECs in the early years and support maternal mental health in the perinatal period. Additionally, the work presented highlights the need for further research to understand the pathways between SECs and mental health outcomes in children.