The potential of life course research. David Blane ESRC International Centre for Life Course Studies in Society and Health (ICLS). Preamble. • Matthias Richter: Bielefeld ZIF workshop 2010; health inequalities, epidemiology, genetics. • Dimitri Mortemans: where’s the sociology & demography? • Summer School on longitudinal & life course research; designed to bring together demography, epidemiology & sociology. • Antwerp 2011 & 2012; Oxford 2013; Amsterdam 2014; Bamberg 2015; Milan 2016. Life course perspective. • Looks for the influence of the past on the present. • Investigates whether such influences are direct, or indirect via contemporaneous factors. • Tests the socially and biologically plausible pathways between the past and the present. • Characterised by inter-disciplinarity, use of longitudinal data, socio-historical context. Three traditions. • Demography: interested particularly in mortality and fertility. • Sociology: strong interests in family formation & dissolution, labour market participation and social mobility. • Epidemiology: mortality, morbidity and health are main outcomes of interest; enthralled currently by genetics, at cost of Virchow’s legacy. Comments. • There are more than three traditions: Glen Elder’s work within social psychology; and others. • Each tradition has much to teach the others; for example the biomedical critique of selfassessed health (objective, subjective). • United by a shared interest in longitudinal data and the statistical methods for their analysis. 1990s Origins The life course now is a core theme in social epidemiology. Model: Accumulation Disadvantages, or advantages, tend to cluster cross-sectionally occupation + residence + area of residence + consumption and accumulate longitudinally. childhood + adulthood + older ages This social process may have a major impact on health through the accumulation of numerous relatively minor effects.* * Blane et al. 1997 European J Public Health Model: Critical periods Extends the idea of biological programming to include Childhood Psycho-social stress at the time of brain maturation may both inhibit child growth and mis-set the developing BP control mechanisms, producing later high BP* Social development Key social transitions** * Montgomery et al. 2000 Archives Disease Childhood ** Bartley et al. 1997 British Medical Journal Model: Pathways Early advantage or disadvantage sets a person on a pathway to a later exposure that is the aetiologically important event.* Educationally successful women (pathway) tend to delay their first pregnancy (aetiologically important event), which increases their risk of breast cancer. * Power & Hertzman. 1997 British Medical Bulletin Real life: child growth, adult occupational strain & blood pressure in early old age. • Slow growth during childhood is associated with raised systolic blood pressure during early old age and with high exposure to occupational strain during adulthood. • High exposure to occupational strain during adulthood interacts with slow growth during childhood to further increase systolic blood pressure during early old age. Models: A judgement Models are difficult to distinguish empirically* and conceptually** Perhaps best to see accumulation as the general social process which drives life course trajectories; with critical periods and pathways, in addition to accumulation, being the biological processes of disease causation** * Hallqvist et al.2004 Social Science and Medicine ** Blane et al. 2007 Revue d’Epidemiologie et de Sante Publique Here’s another example: • Contemporary increase in life expectancy at middle age (mortality rates in pre-SPA quinquennium fell by two-thirds during 19712001). • Explanations tend to be disease-based (CHD) and consider only medical care and risk factor change. But all main causes of death fell by similar amounts. • What would be a life course approach? Strachan-Sheikh model 50 45 40 Level of functioning 35 30 25 20 15 10 5 0 0 10 20 30 40 50 Age (years) 60 70 80 90 100 Strachan-Sheikh model 50 45 40 Level of functioning 35 30 25 20 15 10 5 0 0 10 20 30 40 50 60 70 80 90 Age (years) 1928 1948 1988/ 1993 2013 100 Growth & development: 1928-1948. Social policy and social science context: • Pre-WWI: Rowntree surveys of poverty (standard of living life cycle); 1904 Inter-departmental Committee (school meals). • 1930s: Boyd Orr surveys of child nutrition; Family Endowment Society (family allowances). • WWII: Beveridge Report; full employment; food rationing. • Post-WWII: welfare state. Working life: 1948-1988/1993. Socio-economic context: • Spread of nuclear family; fewer children; better housing. • Full employment (to mid-1970s). • Rising real wages; nutrition. • Holidays; shorter working week. • Labour market niches; early retirement; disability benefit. Retirement: 1988/1993-2013. Emergence of Third Age (end of employment & family responsibilities to loss of functional independence): • Occupational & private second pensions. • Functionally healthy. • Self-realisation & pleasure. • Social participation & networks confer resilience in face of adversity of ageing. • Nutrition; exercise. • Minimum Income for Healthy Living for retired. Life course questions. • Are the drivers of increasing longevity the same as those driving socioeconomic differences in longevity? • Is the biological effect of these improvements in the conditions of life cumulative or are there critical periods? • Which social policies address past disadvantage as well as present need?