Introduction
The WHO Global Commission on the Social Determinants of Health (CSDH) concluded that social injustice is killing on a grand scale. Specifically, the Commission identified inequities in the conditions in which people are born, live, work and age, driven by inequities in power, money and resources driving inequities in health.1 As of 2015, average life expectancy in Japan was 83.7 years and in Sierra Leone, just 50.1 years.2 There clearly remains a rationale for action to improve the lives of those living in poorer countries such as Chad. However, as has been well documented, inequalities are also evident within countries, towns and cities, for example, there is a 20-year gap in male life expectancy between the richest and poorest areas in Glasgow. The average life expectancy for men in India was 62 at the same time that it was 54 for men living in the poorest area of Glasgow—Calton.3 Similarly in Baltimore and Washington DC, those living in the poor part of the city have a life expectancy 20 years shorter than those in a rich part.3
While there are competing views as to the scale of the influence of the social determinants of health (SDH), figure 1, complied by the Kings Fund, demonstrates that social and environmental influences are highly significant, contributing to between 45% and 60% of the variation in health status. Providing universal access to good healthcare is therefore necessary, but insufficient to optimise the health of populations and reduce inequities in health. In England, for example, there is free universal health coverage but widespread, large and persistent inequalities in health between social groups. This is largely because, for many communicable and non-communicable diseases (NCDs), acting at the point at which someone presents with a health problem can be too late. To improve health, reduce health inequalities and reduce costs on healthcare (and other service) budgets, we need to improve the conditions in which people are born, live, work and age.
Given persistent inequalities within and between countries and recognising the human and economic cost of inaction, the Lancet-University of Oslo Commission of Global Governance for Health called for global political solutions that go beyond the health sector alone, and beyond technical solutions and unilateral national action.4 In this paper, we develop and update our previous reporting of progress across the World, in 20105 and 2014.6