Transcript The potential of life course research.

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
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Level of functioning
35
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Age (years)
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Strachan-Sheikh model
50
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Level of functioning
35
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15
10
5
0
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Age (years)
1928
1948
1988/
1993
2013
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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?