Exposure to stress caused by low socio-economic status influences our physiological condition
Lower social and economic conditions in early life can expose individuals to repeated or chronic stress, which in turn may have a serious impact on health in later years. This is what emerged from a series of studies carried out by researchers of the Universidad de Costa Rica and the Université Toulouse III Paul Sabatier. These studies fall within the research framework of the Lifepath project and resulted in two papers published on Psychoneuroendocrinology and Social Science & Medicine.
Growing evidence suggests that poor socio-economic circumstances early in life may have long-term negative effect on health conditions. However, understanding how the social and economic environment affects our health by “getting under the skin” and penetrating the cells, organs and physiological systems of our bodies is still a difficult task to accomplish.
The authors of these two studies analysed a large set of data gathered from more than 7,500 people born in England, Scotland and Wales in a single week in 1958, and focused their attention on composite measure of overall physiological consequences of chronic or repeated exposure to stress, called allostatic load. This physiological index can help to describe how our bodies literally incorporate the world in which we live, while trying to maintain physiological stability in response to environmental challenges.
To measure the allostatic load of all the people involved in the studies, researchers selected fourteen biological parameters to represent cardiovascular, respiratory, metabolic, immune and neuroendocrine systems. They then integrated the results of this analysis with information on participants’ socio-economic conditions and perceived health status, and run a series of statistical tests to identify relevant associations between these sets of data.
They found out that the exposure to stressful and challenging events might be embodied at a biological level, leaving a physiological stamp that may be represented by a higher allostatic load. They went further by studying the effect of different levels of maternal education and paternal occupation, exploring potential differences in their underlying biological mechanisms. Their findings showed that lower maternal education and manual paternal occupation were associated with a higher allostatic load, and that this effect is mainly due to educational, material, financial and health behaviours pathways for both men and women.
Such an approach is not based on the mere absence or presence of diseases, but takes into account the global effect of stress on health in middle-aged adults that have been followed since birth. By doing this, they were able to consider a variety of material, psychosocial, educational and life styles exposures from early life and across the life course.
These two studies strengthen the hypothesis that social challenges become biologically embedded and the identification of a set of biomarkers that may capture this embodiment may be useful for conceptualizing and assessing early preventive intervention before the initiation of deleterious health trajectories.