In 1980, the Black Report — commissioned by the UK government and promptly suppressed — documented systematic differences in health outcomes between social classes in Britain that could not be explained by healthcare access, individual behaviour, or genetics alone. The report’s authors concluded that the primary drivers of health inequality were material: income, housing, working conditions, and the conditions in which children were raised.
Nearly fifty years later, the evidence behind that conclusion has strengthened dramatically. The social determinants of health — the conditions in which people are born, grow, work, and age — are now recognised by the World Health Organization as the most important predictors of population health outcomes. Nowhere is this more visible than in cardiovascular disease.
The Gradient
The relationship between socioeconomic status and cardiovascular disease does not divide neatly into “poor” and “not poor.” It follows a gradient: at every step up the income or occupational ladder, cardiovascular risk is lower. This finding — replicated across dozens of countries and thousands of studies — is called the social gradient in health, and its implications are radical.
If cardiovascular risk were simply a matter of absolute poverty, the solution would be eliminating extreme deprivation. But the gradient means that even people who are not poor by any reasonable definition still have higher cardiovascular risk than those one rung above them. The entire population is arrayed along a socioeconomic health gradient, and the mechanisms behind it operate at every level.
Upstream vs. Downstream
Public health thinking distinguishes between “downstream” interventions — those that address the immediate physiological causes of disease, such as medication, smoking cessation, and dietary change — and “upstream” interventions that address the social, economic, and environmental conditions that produce risk in the first place.
Most cardiovascular prevention policy has focused downstream. Statins are prescribed. Blood pressure medication is dispensed. Smoking cessation services are funded. These interventions have real effects: cardiovascular mortality in Europe has fallen significantly over the past four decades, and pharmacological treatment has played an important role. But downstream interventions work against the tide if upstream conditions continue to generate cardiovascular risk — conditions that include the built environment and neighbourhood-level risk factors that accumulate long before clinical presentation.
The Marmot Review and Its Legacy
The 2010 Marmot Review, commissioned by the UK government, updated the Black Report’s findings for the twenty-first century. Its conclusion was stark: life expectancy in England follows a gradient across the social spectrum, and the additional years of life that would be gained by eliminating health inequality were comparable in scale to the years gained by eliminating cancer as a cause of death.
The review’s recommendations focused on early childhood development, educational attainment, employment and working conditions, minimum income standards, and healthy urban environments. These are not healthcare recommendations. They are recommendations about employment policy, housing policy, education policy, and urban planning — the upstream conditions that determine who bears the greatest cardiovascular burden.
The 2020 Marmot Review found that in the decade since the original report, health inequalities in England had widened and the gradient had steepened. Progress on upstream determinants had been insufficient to counteract the effects of austerity, rising housing costs, and the casualisation of employment.
What the Evidence Requires
The evidence on social determinants does not suggest that individual behaviour is irrelevant to cardiovascular health. Smoking, diet, and physical activity matter enormously. What the evidence suggests is that the distribution of health behaviour across a population is itself shaped by social conditions — that people do not make choices about diet or smoking in a vacuum, but within an environment that their socioeconomic position has done much to determine.
A cardiovascular prevention strategy that addresses only individual behaviour is addressing symptoms while leaving causes untouched. The scale of European cardiovascular inequality — stubbornly persistent despite decades of individual-focused intervention — is one of the strongest arguments in public health for upstream policy. The HHH research across Madrid and Edinburgh adds to that argument with city-level granularity.
