Understanding Life Course

Origins of Life Course

Life course perspective: proposed by Michael Lu and Neal Halfon in 2003 as a new approach to examining racial and ethnic disparities in birth outcomes.
Synthesis of two longitudinal biomedical models: an early programming model and cumulative pathway model.
Offers a broader way of looking at health, over a life span rather than disconnected stages (infancy, adolescence, child bearing years, old age) integrating biological, behavioral, psychological, social and environmental factors which contribute to health outcomes across the course of a person’s life.

Timeline: today’s experiences and exposures determine tomorrow’s health
Timing: health trajectories are particularly affected during critical or sensitive periods
Environment: our social, physical and biological environments strongly affect our capacity to be healthy
Equity: inequities are health determinants

Specific risk and protective factors can be mediated during critical periods.

Critical periods: perinatal and peripubertal periods are sensitive times in human development. Disruptive events that occur during these times can have lasting effects on health.
Early Programming:
- Early programming: early experiences can program an individual’s future health and development, either directly in diseases/conditions or through vulnerabilities to disease in the future.
- Developmental/Fetal origins of disease (Barker): susceptibility to cardiovascular disease, diabetes, cancer, obesity, and high blood pressure are programmed in utero as a response to fetal undernutrition.
Cumulative Pathways:
- Weathering (A. Geronimus)/Cumulative effect: stressors can accumulate over time and have a profound direct impact on health and development through allostatic loads.
- Adverse childhood experiences (ACE study): children exposed to adverse experiences have a graded increased risk for multiple chronic health conditions.
Epigenetics: our physical environment (including food, toxins, etc) can activate heritable changes in gene expression.

Life course, social determinants, and health equity are all complementary, synergistic, and integral to health
Life course helps explain and illustrate how social determinants influence health
Life course helps explain and illustrate how health inequities develop
Life course incorporates human development into our understanding of health

There are multiple critical windows of time for intervening for health
We can act on health through interventions, policy and systems in expanded settings
Policies can have differential effects on families, which is why life course supports comprehensive approaches to health that include the family as the focus of intervention