The same applies to social conditions and anti-inflammatory creams: they get under the skin and act on the body cells. The former last longer though, without always being as beneficial. This is what life course epidemiology teaches us in a collective book resulting from a collaboration between the Swiss National Centre of Competence in Research LIVES and the International Centre for Life Course Studies in Society and Health (ICLS) at the University College London.

Published by LIVES members Prof. Claudine Burton-Jeangros and Dr. Stéphane Cullati from the University of Geneva, along with professors Amanda Sacker and David Blane, who are two authorities in the field at ICLS, this volume brings a fresh look at a still recent area of research by extending the scope of analysis to health in general. For up to now, publications on the subject had mostly addressed chronic diseases.

How does social and economic status produce class differences in terms of health and life expectancy? How, conversely, can health status during childhood later on influence schooling and occupational paths, as well as relationships? The editors’ introduction describes a promising and evolving field of study. They insist on the need for developing preventive policies that take into account all life domains.

The following chapters describe the state of research at the theoretical and empirical levels.

Obesity, scourge of modern times

Laura D. Howe, from the University of Bristol, in collaboration with Riz Firestone, Kate Tilling, and Debbie A. Lawlor, offers a review of the evidence regarding trajectories and transitions in childhood and adolescent obesity. Considered as “one of the most serious public health challenges of the 21st century” by the World Health Organization, obesity concerns 42 million children under the age of five, close to 31 million of these are living in developing countries. This scourge of modern times increases the risk of diabetes, cardiovascular diseases, and social isolation in adult life.

“The study of child adiposity trajectories represents an area where we hope to be able, one day, to determine not only the age period during which children are more at risk of becoming and staying overweight, but also in which social and family conditions, and according to what biological predisposition,” Stéphane Cullati and Claudine Burton-Jeangros explained.

The smile as social marker

Another area where social and family environments are critical is oral health. That is the subject of another chapter by Anja Heilmann, from the University College London, with Georgios Tsakos and Richard G. Watt as co-authors. Teeth problems are a source of multiple difficulties and suffering in the short, middle, and long term. Education may prevent part of those, but treatment remains hardly accessible to the underprivileged. Moreover, it is far from being a priority for policy makers.

Other diseases occur independently of social conditions. That is the case of cystic fibrosis. Yet important differences will appear in the life course of the most favoured patients versus those who live in a deprived context, show David Taylor-Robinson, from the University of Liverpool, with Peter Diggle, Rosalind Smyth and Margaret Whitehead.

Calculate and predict inequalities

Among the nine contributions that compose the content of the book, three address important methodological issues, which arise for researchers willing to carry out longitudinal studies on health in a life course perspective. One chapter, written by a Geneva team linked to the NCCR LIVES, presents statistical models that include both stability and change. Paolo Ghisletta, Olivier Renaud, Nadège Jacot, and Delphine Courvoisier demonstrate how these methods allow analysis of the interaction between individuals and their context over time.

Asked about the challenges posed by life course epidemiology, Claudine Burton-Jeangros and Stéphane Cullati mentioned several limitations, which remain to be overcome: getting access to representative samples of the general population, and not only to sub-populations of patients; having longitudinal databases that are sufficiently rich in data on family, work, leisure, life conditions during childhood, health behaviours and status (including biomarkers); repeating these studies on new cohorts; encouraging the development of statistical models able to process large quantities of repeated data; and finally, collect also qualitative data through interviews with participants, in addition to quantitative data, in order to better capture the meaning that individuals give to their health trajectories, in relation to changes in their life conditions.

Protect family life

On the basis of current knowledge, both authors consider that social policy should better protect childhood and family life: “Ensure the best conditions for our kids, be it during intrauterine life, at birth, during early childhood and the early phases of mental and physical development, promote a good social integration during adolescence, all these factors represent key elements for a future healthy life. However, health promotion, which goes far beyond the sole sector of public health programmes, is not a priority, as the voting against a law on prevention recently showed in Switzerland”, they regret.

>> Burton-Jeangros, C., Cullati, S., Sacker, A., & Blane, D..  (2015). A life course perspective on health trajectories and transitions. Life course research and social policies (Vol. 4, p. 213). New York: Springer.

Available under Open access