Elsevier

Social Science & Medicine

Volume 55, Issue 11, December 2002, Pages 2005-2016
Social Science & Medicine

Building an inter-disciplinary science of health inequalities: the example of lifecourse research

https://doi.org/10.1016/S0277-9536(01)00343-4Get rights and content

Abstract

Across the post-industrial world, new public health strategies are being developed with the goal of reducing the socio-economic gradient in health. These new strategies are distinguished by a commitment to tackling the macro determinants of health inequalities through policies informed by scientific evidence. The engagement with macro determinants and with scientific evidence presents a major challenge to the health inequality research community. This is not only because of the complexity of the links between distal causes, proximal risk factors and health outcomes. It is also and more importantly because of the narrow disciplinary base of health inequality research. Grounded in social epidemiology, health inequality research has illuminated the pathways which run from individual socio-economic position to health—but has left in shadow the factors which influence socio-economic position. Broadening the evidence base to include these structural processes requires a new science of health inequalities, resourced both by epidemiological research and by research on social inequality and social exclusion. The paper demonstrates how such an inter-disciplinary science can be constructed. Taking lifecourse research as its example and the UK as its case study, it nests epidemiological research within social policy research: setting evidence on the health consequences of cumulative exposures within research on lifecourse dynamics, and locating both within analyses of how state policies can amplify or moderate inequalities in socio-economic position.

Introduction

Health inequalities are moving up the policy agenda of post-industrial societies. Within and beyond Europe, public health policy is being reconfigured around the goal of reducing socio-economic differentials. It is a goal which is driving new health strategies in the United Kingdom (UK), with the government committed ‘to narrow the health gap in childhood and throughout life between socio-economic groups’ (Secretary of State, 2000, pp. 166 and 167). At the same time, reducing health inequalities has been incorporated into Italy's 1999–2000 National Health Plan and Sweden is developing a health strategy structured around measurable equity targets (Ministero della Sanita, 1998; National Public Health Commission, 1999). Looking beyond Europe, New Zealand has launched a new health strategy to deliver reductions in health inequalities (King, 2000). These national initiatives are framed by the international equity agenda established by WHO in its Health For All charter and reaffirmed in its Health21 programme (WHO (1998), WHO (1998)).

There are important differences of emphasis between the national strategies in the relative weight they give to regional and ethnic inequalities, for example, and in their commitment to measurable equity targets. But these differences are set within a broader similarity of perspective and approach. It is a perspective which acknowledges the macro determinants of health inequalities and an approach which seeks to tackle them through policies informed by scientific evidence.

The new health strategies are distinguished, firstly, by a perspective which recognises that ‘the roots of health inequalities run deep’ (Secretary of State, 1999, p. 44). Thus England's new health strategy is seen as a radical attack on ‘fundamental causes’, particularly as these manifest themselves in ‘disadvantage in all its forms—poverty, lack of educational attainment, unemployment, discrimination and social exclusion’ (Secretary of State, 2000, p. 106). In Sweden, the new strategy also marks a break with the past, shifting the focus of public health policy from tackling disease outcomes to tackling their social determinants (Ostlin & Diderichsen, 2000). In New Zealand, too, the new strategy is distinguished by its commitment to tackling ‘the key determinants of health (which) include income, education, employment, housing’ (King, 2000, pp. 4 and 5).

Tackling key determinants is recognised to require action by, and co-ordination between, policy sectors that could exert leverage on them. The emphasis is on inter-sectoral policies which address both individual risk factors and their underlying social causes. Evidence has been accorded a central place in the development of these policies, with independent commissions and inquiries established to review the science base for an inter-sectoral approach to public health (Independent Inquiry, 1998; National Advisory Committee, 1998; National Public Health Commission, 1999). But, as these reports make clear, building science into policy is a far from straightforward process. One major problem is that inter-sectoral policies to tackle the determinants of health inequalities require an inter-disciplinary science of health inequalities—and this science has yet to be built. Its development turns on the integration of research on health inequalities and research on social inequality, research located in separate disciplinary fields.

Research on health inequalities has been grounded in social epidemiology, a branch of medicine where the focus is on identifying and quantifying the individual factors that might explain the socio-economic gradient in health. Influential critiques by McKinlay and by Krieger have highlighted the need for a science of public health which engages with upstream determinants and bridges the divide between social epidemiology and social science (Krieger, 2000; Pearce & McKinlay, 1998). In a similar vein, Navarro has argued for a political economy of health inequalities which incorporates the influence of social policies and the political ideologies which shape them (Navarro & Shi, 2001). Recognising the need to lengthen the causal chain, epidemiological models are increasingly including the social structure as an over-arching determinant of health (see, for example, Brunner & Marmot, 1999; Dahlgren & Whitehead, 1991; Diderichsen, 1998). While these extended models are important conceptual advances, they are hard to operationalise empirically. This is because the processes through which the social structure shapes the social circumstances and health experiences of different socio-economic groups are difficult to detect through the individual data on which health inequalities research continues to rely.

These broader social processes are mapped in studies of social inequality, social polarisation and poverty. Here it is social policy which provides the disciplinary base, a research tradition aligned more closely with sociology and welfare economics than with social epidemiology. It is a tradition which has long been concerned with how socio-economic disadvantage is reproduced across and between generations and with the role that governments can play in moderating inequalities in life chances and living standards. However, while studies of social inequality recognise that poor health is associated with social disadvantage, they do not contain the battery of measures of risk exposure and health outcomes regarded as essential for sound epidemiological research.

A minimum requirement for an evidence-informed public health policy is the integration of these two fields of research (Graham, 2001). Building such a science is, of course, no simple task, and one short paper can only signal its scope and potential. The paper does so by focussing on lifecourse research. This is a developing field in the disciplines of social epidemiology and social policy and a point of intersection with the policy domains of public health and social exclusion to which the two disciplines relate. A lifecourse focus still leaves a large canvas to cover: material, psychosocial and behavioural influences take their toll over time both on a broad range of intermediate risk factors and on multiple dimensions of physical and mental health. The potential for an inter-disciplinary approach to health and social inequality is therefore illustrated primarily with respect to socio-economic determinants and physical health outcomes. The UK provides the case study for this approach: an instructive example because lifecourse influences on health and socio-economic influences in lifecourse have been both pronounced and extensively studied. It therefore illuminates the contribution that inter-disciplinary perspectives can make to the evidence-base of public health policy.

The paper is divided into three parts. The sections below briefly consider the epidemiological evidence on lifecourse influences on health inequalities and the conceptual models developed to capture the underlying etiological processes. The central two sections examine insights from social research into the dynamics of social inequality over the lifecourse and in times of rapid economic and social change. The final part of the paper points to evidence which suggests increasing lifecourse inequality is not the inexorable outcome of the shift to a post-industrial society: government policies can play a key role in moderating the effects of this transition and in equalising living standards across the lifecourse.

Section snippets

Lifecourse influences on health inequalities

The public health community has long been alert to the fact that diseases which make a major contribution to the socio-economic gradient in health have their origins in risk factors operating in both early and later life (Kuh & Davey Smith, 1993).

In the late 19th and early 20th century, the high rates of infant and childhood mortality among the urban poor focussed attention on early life disadvantage and the transmission of its health effects from mother to child (for example,

Modelling lifecourse influences on health inequalities

As this accumulating body of research suggests, the relationship between disadvantage at different life stages and health in adult life is both complex and dynamic. A range of conceptual models has been proposed to capture these temporal relationships. Three models are commonly identified: critical period models, accumulation models and pathway models (see, for example, Kuh & Ben-Shlomo, 1997; Kuh & Wadsworth, 1993; Power & Hertzman, 1997).

Critical period models suggest that the diseases which

Socio-economic inequalities across the lifecourse

Longitudinal studies in Britain provide a detailed picture of how the class structure is reproduced across and between generations—and how, in consequence, disadvantage runs from parent to child and from childhood to adulthood. While upward mobility occurs, the odds are stacked against children born to parents on the lower rungs of the class ladder (Blane et al., 1996; Harding, Rosato, & Brown, 1998). As a result, children on these lower rungs are at risk of exposure to disadvantage at periods

Widening inequalities in lifecourse trajectories and increasing childhood poverty

The transition from an industrial to a post-industrial society is marked by rapid social change. Central to the process is the shift from manufacturing to service industries, a trend which is transforming established and predictable lifecourse trajectories. It offers those in advantaged positions greater opportunities to build rewarding employment and domestic careers, and to develop lifestyles which promote health. But the same trend is leaving those without the class capital of family

Policy influences on lifecourse disadvantage

Post-industrial societies are characterised by the diversity of their welfare systems, systems which rest on different degrees of state investment in welfare services and of state regulation of the labour market. In the universalistic systems of the Nordic countries, there is active intervention in the labour market, and households across the socio-economic hierarchy depend heavily on welfare services and benefits provided by the state. There is a correspondingly high level of state support for

Conclusions

In an increasing number of countries, governments are pursuing inter-sectoral policies to tackle the social determinants of health inequalities. They are looking to the scientific community for evidence to guide the development of these policies. This requires an inter-disciplinary science: one capable of capturing both the dynamics and the health consequences of social inequality.

The paper has outlined how such an evidence-base can be constructed. It has opened up the interface between the

Acknowledgements

This paper has been stimulated and informed by my involvement in a range of research and policy networks, including the Independent Inquiry into Inequalities in Health, the ESRC Health Variations Programme (award number: L128341002), the European Science Foundation Program on Social Variations in Health Expectancy (Lifecourse Working Group), and the EU Network on Policies and Interventions to Reduce Health Inequalities. The paper has also benefited from the helpful comments of Chris Power,

References (89)

  • A.B. Atkinson

    Income inequality in the UK

    Health Economics

    (1999)
  • D.J.P. Barker

    The foetal and infant origins of inequalities in health in Britain

    Journal of Public Health Medicine

    (1991)
  • D. Barker

    Mothers, babies and health in later life

    (1998)
  • M. Bartley et al.

    Birthweight and later life disadvantage

    British Medical Journal

    (1994)
  • L. Berney et al.

    Lifecourse influences on health in old age

  • V. Berridge

    Science and policyThe case of postwar British smoking policy

  • D. Blane et al.

    Association of cardiovascular disease risk factors with socio-economic position during childhood and during adulthood

    British Medical Journal

    (1996)
  • B. Botting et al.

    Teenage mothers and the health of their children

    Population Trends

    (1998)
  • J. Bradshaw et al.

    Poverty in the UK. A comparison with nineteen other countries

    Benefits

    (1997)
  • E. Brunner et al.

    Social organisation, stress and health

  • J. Bynner

    New routes to employmentIntegration and exclusion

  • J. Bynner et al.

    Getting on with qualifications

  • Bynner, J., & Parsons, S. (2002). Social exclusion and the transition from school to work. Journal of Vocational...
  • T. Clark et al.

    Election briefing, commentary 84

    (2001)
  • G. Dahlgren et al.

    Policies and strategies to promote equity in health

    (1991)
  • G. Davey Smith et al.

    Adverse socio-economic conditions in childhood and cause-specific adult mortalityProspective observational study

    British Medical Journal

    (1998)
  • G. Davey Smith et al.

    Lifetime socio-economic position and mortalityA prospective observational study

    British Medical Journal

    (1997)
  • Department of Social Security (1992). Households below average income 1979 to 1992/1993. London:...
  • Department of Social Security (2000). Households below average income 1994/1995 to 1998/1999. London:...
  • F. Diderichsen

    Understanding health equity in populations

  • R. Doll et al.

    Smoking and caricoma of the lung. Preliminary report

    British Medical Journal

    (1950)
  • J.W.B. Douglas

    The home and the school

    (1964)
  • G. Esping-Andersen

    The three worlds of welfare capitalism

    (1990)
  • J. Falkingham et al.

    Lifetime incomes and the welfare state

  • A. Forsdahl

    Are poor living conditions in childhood and adolesence an important risk factor for arteriosclerotic disease?

    British Journal of Preventive Social Medicine

    (1977)
  • A. Forsdahl

    Living conditions in childhood and subsequent development of risk factors for arteriosclerotic heart disease

    Journal of Epidemiology and Community Health

    (1978)
  • J.E. Floud et al.

    Social class and educational opportunity

    (1996)
  • H. Graham

    Research into policy

  • F. Green

    Training the workers

  • A.E. Green et al.

    Where are the jobless?

    (1998)
  • P. Gregg et al.

    Child development and family income

    (1999)
  • P. Gregg et al.

    Poor kidsTrends in child poverty in Britain, 1968–96

    Fiscal Studies

    (1999)
  • P. Gregg et al.

    More work in fewer households

  • S. Harding et al.

    Who becomes a lone mother?

    Population Trends

    (1998)
  • Cited by (0)

    View full text