Reducing inequalities in child health: understanding pathways, interventions and policies

RELEVANCE OF THE PROBLEM

REDUCING HEALTH INEQUALITIES AND IMPROVING CHILD HEALTH ARE UK and INTERNATIONAL POLICY GOALS. Poverty and social inequality harm children's health. The poor health associated with poverty limits children's potential and development, leading to poor health and life chances in adulthood. The costs to society as a whole of the resulting inequalities, which have their origins in childhood, amount to around £60 billion per year in the UK.

Tackling the poorer health of poorer children is a major challenge for public health in the UK. For this to happen, however, we need to identify how to break the link between adverse socio-economic conditions (SECs) with worse child health. One major challenge is that, while the association of poverty and children's health is clear, we lack understanding of the complex pathways linking adverse social conditions to worse child health. Another challenge for research is that it is rarely possible to study the sorts of population-wide interventions that might make a difference using conventional methods, such as randomized controlled trials.

AIMS and OBJECTIVES

THIS RESEARCH AIMS TO IDENTIFY THE KEY MECHANISMS THAT LEAD TO POORER HEALTH IN POORER CHILDREN AND TO EVALUATE THE EFFECTS OF INTERVENTIONS AND POLICIES THAT HAVE THE POTENTIAL TO IMPROVE THE SITUATION. I will do this using some of the largest contemporary datasets in the world that follow-up children over the course of their lives in the UK and Denmark. These include the UK Millennium Cohort Study, the Welsh Electronic Cohort of Children, and the Danish National Birth Cohort. I will quantify the main causes and consequences of inequalities in child health and evaluate the impacts of public health, welfare and education interventions with the potential to break the link between poverty and poorer health.

Taking childhood asthma, one of the most common longterm conditions in childhood, as an example, I have shown that children living in poorer socioeconomic conditions are more likely to have wheezing in childhood. Examining possible reasons, I found that the poorer children with asthma were more likely to have mothers who smoked during pregnancy and who were less likely to breast-feed. These two reasons accounted for most of the differences in asthma between disadvantaged and advantaged children that we observed. In my proposed research, I will apply statistical methods to see what would happen to inequalities in childhood asthma in the UK population if, for example, effective interventions to increase breast-feeding (such as baby friendly support policies in maternity hospitals) were fully implemented nationwide. The research will also show what effect longterm conditions like asthma have on attendance at school and exam results. Poor child health leading to poor educational performance is likely to be an important way in which health inequalities are generated, but this is not well understood currently.

APPLICATIONS and BENEFITS
This research will directly inform policymakers and practitioners grappling with how best to break the link between child poverty and poorer health, and thereby improve health and reduce health inequalities across the life course. By applying new methods to important child health conditions I will develop a better understanding of HOW TO REDUCE INEQUALITIES IN CHILD HEALTH. I will work with policy makers and practitioners to make sure that the findings make a difference to the health and wellbeing of children, families and whole populations. Though I'll undertake most of the work in Liverpool, I have brought together an international collaboration of researchers from a range of disciplines to address this critical public health issue, which will provide superb research training. The information generated in my research programme has great potential for having a population-wide impact, a reduction in health inequalities and clear overall economic benefits.

AIM: To elucidate causal pathways and consequences of health inequalities in children, and to quantify the impact of interventions and policies to interrupt the generation of inequalities in health across the life course.

RESEARCH QUESTION 1: To what extent do key exposures, for example health behaviours and family income, mediate the association between childhood disadvantage and important child health outcomes such as mental health or asthma?

RESEARCH QUESTION 2: Does childhood illness have different impacts on educational attainment and early adult transitions into employment depending on the socio-economic conditions in which the children grow up?

RESEARCH QUESTION 3: To what extent do interventions that target mediating pathways, such as poverty or risk factor reduction, reduce health and socioeconomic inequalities in childhood?

METHODS: 1) Causal mediation analysis in longitudinal data 2) Simulation of trials of interventions 3) Evaluation of natural policy experiments 4) Data linkage. I will use some of the world's largest contemporary datasets on children including the Millennium Cohort Study (MCS); the Welsh Electronic Cohort for Children (WECC); and the Danish National Birth Cohort (DNBC). I will focus on outcomes that influence later adult health, are socially patterned, and amenable to intervention (e.g. measures of child development, mental health, asthma). I will use the estimates from causal mediation analyses, combined with estimates from controlled trials, to model the effect of public health, welfare and education interventions interventions on child health and social inequalities. I will apply recently developed methods for evaluating natural policy experiments.

SCIENTIFIC AND MEDICAL OPPORTUNITIES: Results will inform policy makers and the wider public. Health outcomes for children in the UK are poor leading to huge human and economic costs. I will develop a better understanding of how to reduce inequalities in child health.

The academic beneficiaries are outlined above. Non-academic beneficiaries are principally:

CHILDREN AND YOUNG PEOPLE (C&YP) - "Britain is failing its young children on a grand scale" according to Fair Society, Healthy Lives, the 2010 English review of health inequalities. Furthermore all children have a right to the best possible health, as enshrined in the UN Convention on the Rights of the Child. C&YP will ultimately derive benefit from the acquired knowledge through improvements in population health and reduction of health inequalities resulting from the use of these research findings. The voices of C&YP are often not considered in discussions around health inequalities; the active involvement of C&YP in the project is an end in itself, empowering them to critically engage with issues relating to social inequalities.

POLICY MAKERS - Improving child health and reducing health inequalities are priorities at national and international levels. There is a clear need in public policy to shift investment to have an impact on the early years of children's lives, and to invest in interventions for which there is good evidence of effectiveness. The recent BMA report "Growing up in the UK - Our children deserve better" highlights the need for longitudinal studies to improve the evidence base for interventions that can achieve maximum benefits. I expect this programme of research will inform evidence-based policies in child health; and influence resource allocation decisions that affect children.

CHILD HEALTH PRACTITIONERS AT LOCAL LEVELS - The findings will be relevant to commissioners and managers of health services, paediatricians and the full range of child health practitioners to inform practice at local levels. For instance the project will provide an in-depth longitudinal description of health, healthcare and social outcomes for children with a range of chronic conditions in the UK and Denmark. This information will contribute to achieving equitable delivery of care within health systems. This is a priority in the NHS in England, with NHS bodies required to reduce inequalities in access to, and the outcomes of healthcare. The findings will also lead to policies and interventions to improve the care of children with chronic conditions.

THE WIDER COMMUNITY INVOLVED IN CHILDREN'S LIVES, INCLUDING THE EDUCATION, SOCIAL CARE AND CHARITABLE SECTORS - My research will increase our understanding of the effect of illness in childhood on educational and social outcomes. These findings will be of direct interest and relevance to the education sector, leading to policies and interventions in the medium to long term to militate against the effects of ill health on education trajectories - an important pathway to social inequalities in adulthood. Charities and NGOs will use the research findings as they influence and advocate for policies and interventions to improve child health. The findings will inform current efforts to better integrate public services for children across education, social care, and health.

SOCIETY AS A WHOLE - The healthy development of all children benefits all of society by providing a secure foundation for future health, learning and economic productivity. Better policies will lead to more effective national and international action to reduce inequalities in child health and the social determinants of child health. Informed by the information generated in my research programme this has great potential for overall societal gains, a reduction in health inequalities and clear net economic benefits. As outlined in the case for support, the costs of inequalities are huge, and inaction on this issue is simply not affordable. Health and social inequality is one of the defining issues of our era, and is part of the mainstream public discourse. In the short term my research findings will add empirical evidence to the inequalities debate, and are likely to be of great interest to the general public.