Lecture 9 – “In Sickness and in Wealth”

- AKA Social Gradient in Health
- Consistently observed inverse association between SES and poor health outcomes
- Strength of gradient varies at different ages
- Gaps greatest in mid-to late-adulthood
- Gap narrows at age 65
- Weaker gradient for children is less susceptible to reverse causation concerns, less likely that poor health is "causing" low income

- Lower family income is linked with worse health
- Compared with adults in the highest-income group, poor adults are nearly five times as likely to report poor or fair health

- As household income increases, rate of pediatric trauma hospitalizations declines
- Regardless of race/ethnicity, higher levels of education are associated with lower prevalence of NOT reporting "excellent or very good" health

- Education: direct - knowledge, skills, and abilities impact health behaviors; indirect - eduction, employment, income = access to resources
- Work/employment: direct - working conditions and jobs strain; indirect - employment yields income, benefits, and security
- Neighborhood/communities: direct - pollution, toxins, violence; indirect - norms, violence (stress), access to healthy resources, parks, social cohesion, economic opportunities

- Good in small doses
- When stress response systems work on overtime, we produce too much cortisol (and other hormones) which floods our bloodstream with glucose, increase heart rate, raise blood pressure, and put body on alert
- Overtime, increased cortisol impairs immune function, can inhibit memory, and can even cause areas of the brain to shrink
- Leads to increased atherosclerotic plaque, heart disease, and death
- Stress hormones released: adrenaline, noradrenaline, cortisol

- The effects of the chronic wear and tear that repeated exposure to stress has on the body
- Allostatic load is higher among lower SES individuals
- Differential exposure to acute and chronic stress further exacerbate the health-wealth gradient

- Two main hypothesis:
1. Social causation hypothesis
2. Health selection hypothesis
- A third: confounding contextual factors

- SES causally affects health
- Mechanistic process: lower SES may be associated with limited access to health care, higher stress, lower ability to process health information, unhealthy behaviors, reduced access to health-producing environments and products, etc., leading to poorer health outcomes

- Health affects SES (Health SES)
- "Social drift" hypothesis: Unhealthy persons "drift down" to or fail to escape from poverty
- Mechanistic process: childhood health affects adult SES indirectly via its affect on the sick child's individual's ability to maintain SES status (e.g., via educational performance) or to rise out of low SES status
- Indirect: social mobility is selective on determinants of health, not necessarily on health itself

- Economic conditions, social factors, and the physical conditions in the environment in which people are born, live, learn, play, work, and age which, in turn, are shaped by the global distribution of money, power, and resources (WHO; HP 2020)
- Prerequisites of health such as peace, shelter, education, food, income, sustainable resources, equity (Ottawa Charter for Health Promotion)
- "Upstream" factors that impact health and the distribution of health

Observed population-specific differences in morbidity, mortality, well-being, HRQOL, access to care, and healthcare quality that exist even after controlling for behavior and other characteristics

- SDH and disparities are inextricably linked
- Differences in SES affect differences in the distribution of resources and risk factors which affect differences in behavior which affect differences in health outcomes

- Differences in structural determinants of health create differences in access to social determinants of health which create differences in health behavior which leads to differences (disparities) in health outcomes
1. Structuralist views of disease: SES is a "fundamental cause" of disease
- Social (distal) factors operate both directly to influence health and indirectly (e.g., by influencing behavior) to affect health
- A more distal view of health: the "causes of the causes"
2. Cultural/Behavioral (proximal) causes of disease: easy to focus attention here because behaviors are more proximal to disease in the causal chain
- Easier to establish or hypothesize "biological plausibility"