Life course Epidemiology Flashcards
what did life course epidemiology aim to integrate in 1997
fetal/developmental origins of adult disease
adult lifestyle
social causation theories
what is life course epidemiology
study of biological, behavioural and psychological pathways that link physical and social exposures during gestation, childhood, adolescence and adult life, across generations to adult health function and disease risk
what can life long epidemiology be useful for
ageing research
why is time important in life course approach
encourages consideration of timing, duration and temporal ordering of different exposures and characteristics of any one specific exposure/phenotype over time
what do critical sensitive period models show
an exposure in earlier life has lifelong effects on structure or function (may or may not be modified by later experience)
what is the critical period
only time during which an exposure has an effect
e.g barker hypothesis, thalidomide
what is the sensitive period
time during which exposure has greater effect than outside this period
e.g learning a second language
outline the accumulation of risk model
exposures/insults gradually accumulate across life through episodes of illness/injury , adverse environmental conditions and health damaging behaviour
- accumulation of independant risks
- clustering of risk
- chains of risk (additive and trigger)
what is accumulation of independent risks
accumulation of exposures to different uncorrelated risk factors causes long term damage and increases disease risk
what is accumulation of clustered risk
accumulation of exposure to different risk factors which are clustered (because they are each associated with another risk factor) and cause long term damage and increased disease risk
what is chains of risk
the impact of some factor in childhood may lie less in immediate behavioural change but it sets into motion a chain reaction in which one ‘bad’ thing leads to another or vice versa a good thing
what are the two types of chains of risk
additive effect model
trigger effect model
outline the additive effect chains of risk model
each exposure not only increases the risk of subsequent exposure but also has independent effect on disease (irrespective of later exposure)
what is trigger effect chin of risk model
earlier exposures influence risk of subsequent exposures BUT have no effect on disease risk without the final link in the chain
what are limitations of the accumulation of risks model
focus on lifetime exposures rather than response
not all outcomes are hard disease end-points
do not represent complex and dynamic interplay of developmental, risk factor (behavioural and environmental) and ageing-related trajectories across life
what are 2 ideal features of studies used to test life course hypotheses
- assessment of outcomes - at different life stages, with baseline measures of age-related decline, with repeated measurements over time
- data on potential risk factors - from birth or earlier onwards, repeat measurements over time, that are potentially modifiable
what are 3 studies used for life course research
national and regional birth cohorts
historical cohorts
adult cohorts with retrospective data on childhood
what are the benefits of having multiple ‘life course’ studies
no one study has data on all measures of interest
faciliates study of cohort differences - are associations generalisable?
important differences in environment across time and between countries
may impact on associations observed and relative to public health importance
can help distinguish between causal and confounded associations
what are the 4 national british birth cohort studies
- national survey of health and development
- national child development study
- 1970 british birth cohort
- millenium cohort study
what is an example of life course epidemiology
a life course approach to chronic pain
are there different life course profiles of back pain in 1946 british birth cohort study?
what were the key findings of the back pain study
1.serious illness before age 25 was associated with increased risk of chronic widespread pain at age 68
2. exposure to smoking any time in adulthood and cumulative exposure to financial hardship both associated with increased risk at age 68
in the chronic pain study how do childhood factors relate to different longitudinal profiles of back pain?
association found between persistent back pain and taller childhood height in women, abdominal pain in adolescence, poor care in childhood and poorer maternal health
what does a life course approach encourage
careful consideration of time in epidemiological analyses
why was life course epidemiology revived in the 1990s?
in response to different models of disease causation being in conflict like developmental origins of health and disease hypothesis and adult lifestyle models
