Differences in living and working conditions may translate in health inequalities. In fact, life expectancy is shorter and diseases are more common further down the social ladder. Being poor and unemployed does not do any good to your health.
It may seem obvious, but it is not.
The World Health Organization has set an ambitious goal for its global health strategy: reducing premature mortality from the major non-communicable diseases, like cancers and cardiovascular diseases, by 25% by 2025. However, the so-called 25x25 plan does not explicitly include social and economic status among those factors that may shorten people’s life.
That is why is not that obvious that social conditions can have a grim effect on health.
That is also why a study just published on The Lancet is so important, because it provides well-founded evidence that a low socioeconomic profile does represent a serious health risk factor. Rather, a poor job status is one of the gravest factors, since it may have an impact on premature mortality comparable to that of smoking and physical inactivity.
In fact, the authors of the research found that having a lower occupational position can take away 2.1 years of life on average from a person. What about other known risk factors? Smoking is associated with the loss of 4.8 years of life; diabetes, 3.9; and physical inactivity, 2.4. High alcohol intake can take away one year of life.
These are the results obtained by researchers of the LIFEPATH consortium, a research project funded by the European Commission, which investigates the biological pathways underlying social differences in healthy ageing. They carried out an original multicohort study on more than 1.7 million adults followed up for mortality for an average of 13 years. They then measured a series of factors that could have been associated with these deaths, in order to build effective risk models. Finally, they tried to estimate how many years of life could have been spared, if exposure of the population to the risk factor of interest was reduced to the minimum risk level.
Most importantly, socioeconomic status was included among the factors analysed.
“Poor social and economic circumstances seem to kill people at the same rate as powerful risk factors such as obesity, and hypertension. And since these circumstances are modifiable, they should be included in the list of risk factors targeted by global health strategies,” argues Silvia Stringhini, researcher at Lausanne University Hospital in Switzerland and lead author of the study. "About 20% of premature mortality is due to poor socioeconomic conditions comparing to 30% for smoking, 25% for physical inactivity, but around 0-10% for diabetes, obesity and physical inactivity. The association between socioeconomic status (SES) and mortality shows a gradient. A graded association between occupational position and mortality was observed in both men and women (HR for one unit decrease in SES 1·19, 95% CI 1·17–1·20 in men and 1·15, 1·13–1·18 in women, p<0·0001 for both)".
Socioeconomic status was measured in terms of low occupational class, according to the European Socio-economic Classification, and the results are largely consistent with previous studies that used income or education as a measure of socioeconomic status. Moreover, the association of low socioeconomic status with premature mortality was consistent across causes of death, while that of the 25x25 risk factors was generally stronger for cardiovascular disease mortality than for cancer and for mortality for other causes.
The link between low socioeconomic status and poor health is well documented, but that is not the point of the paper. The real emphasis here was on the comparison of social and economic circumstances with other major risk factors for non-communicable diseases.
Furthermore, the results obtained by Stringhini and her colleagues clearly point out that current global strategies and actions defined in the 25x25 health plan and the Global Burden of Diseases surveillance programme potentially exclude a major determinant of health from the agenda. A lack of consideration of the interrelation between social circumstances and health is also evident in the Sustainable Development Goals, since reducing health inequalities is not mentioned as an explicit goal.
Like the risk factors currently targeted by global health strategies, socioeconomic circumstances are modifiable by policies at the local, national and international levels. However, “downstream” intervention, such as smoking cessation assistance or dietary advice might favour privileged persons, who can more easily have access to these programs and change their habits. Compared to them, “upstream” intervention, such as work incentive programs or early education programs for children, are more likely to have a fair impact and might be a cost-effective way to reduce inequalities in health.
The main aim of LIFEPATH consortium is to understand the biological pathways through which social inequalities lead to health inequalities, in order to provide evidence for public health institutions and policymakers. By demonstrating a comparable health impact of low socioeconomic status to that of major risk factors, this study suggests that socioeconomic circumstances, in addition to the 25x25 factors, should be treated as a target for local and global health strategies, health risk surveillance, interventions and policy.
