Life course Epidemiology

Question 1

what did life course epidemiology aim to integrate in 1997

Answer 1

fetal/developmental origins of adult disease
adult lifestyle
social causation theories

Question 2

what is life course epidemiology

Answer 2

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

Question 3

what can life long epidemiology be useful for

Answer 3

ageing research

Question 4

why is time important in life course approach

Answer 4

encourages consideration of timing, duration and temporal ordering of different exposures and characteristics of any one specific exposure/phenotype over time

Question 5

what do critical sensitive period models show

Answer 5

an exposure in earlier life has lifelong effects on structure or function (may or may not be modified by later experience)

Question 6

what is the critical period

Answer 6

only time during which an exposure has an effect
e.g barker hypothesis, thalidomide

Question 7

what is the sensitive period

Answer 7

time during which exposure has greater effect than outside this period
e.g learning a second language

Question 8

outline the accumulation of risk model

Answer 8

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)

Question 9

what is accumulation of independent risks

Answer 9

accumulation of exposures to different uncorrelated risk factors causes long term damage and increases disease risk

Question 10

what is accumulation of clustered risk

Answer 10

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

Question 11

what is chains of risk

Answer 11

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

Question 12

what are the two types of chains of risk

Answer 12

additive effect model
trigger effect model

Question 13

outline the additive effect chains of risk model

Answer 13

each exposure not only increases the risk of subsequent exposure but also has independent effect on disease (irrespective of later exposure)

Question 14

what is trigger effect chin of risk model

Answer 14

earlier exposures influence risk of subsequent exposures BUT have no effect on disease risk without the final link in the chain

Question 15

what are limitations of the accumulation of risks model

Answer 15

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

Question 16

what are 2 ideal features of studies used to test life course hypotheses

Answer 16

1. assessment of outcomes - at different life stages, with baseline measures of age-related decline, with repeated measurements over time
2. data on potential risk factors - from birth or earlier onwards, repeat measurements over time, that are potentially modifiable

Question 17

what are 3 studies used for life course research

Answer 17

national and regional birth cohorts
historical cohorts
adult cohorts with retrospective data on childhood

Question 18

what are the benefits of having multiple ‘life course’ studies

Answer 18

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

Question 19

what are the 4 national british birth cohort studies

Answer 19

1. national survey of health and development
2. national child development study
3. 1970 british birth cohort
4. millenium cohort study

Question 20

what is an example of life course epidemiology

Answer 20

a life course approach to chronic pain
are there different life course profiles of back pain in 1946 british birth cohort study?

Question 21

what were the key findings of the back pain study

Answer 21

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

Question 22

in the chronic pain study how do childhood factors relate to different longitudinal profiles of back pain?

Answer 22

association found between persistent back pain and taller childhood height in women, abdominal pain in adolescence, poor care in childhood and poorer maternal health

Question 23

what does a life course approach encourage

Answer 23

careful consideration of time in epidemiological analyses

Question 24

why was life course epidemiology revived in the 1990s?

Answer 24

in response to different models of disease causation being in conflict like developmental origins of health and disease hypothesis and adult lifestyle models