Ch 7 - Determinants of Health: Social Relationships Stress

go through the pp slides, very table heavy

social determinants as a determinant of health

• WHO recognizes human social relationships as an important social determinant of health throughout life

• loneliness and social isolation are linked to poorer health, depression and increased risk of early death

evolution of social behavior in animals and humans

• natural selection

• some species including humans have evolved as social species, others have not — depends on what enhances survival & reproductive success

natural selection

• selects for characteristics that increase the reproductive success of individuals or groups

• also selects for behavior that improves the likelihood of survival & reproductive success

evolution of human social behavior

• humans generally more successful with a strong social network

  • networks of family and close friends provide support in difficult times (not superficial friendships)

  • social support improves survival and reproductive success

    • think of raising children alone vs with extended family support

what do human societies get from social networks and community living?

• cooperative behaviors improve survival and reproductive success → natural selection selects for cooperative behavior

  • shared ideas & inventions allow societies to adapt and thrive 

  • learned behavior & skills enable rapid adaptation to new, unfavorable, or changing habitats

  • shared efforts (food production, etc.) allow us to do more as a society

• some close interactions are stressful or just tolerated; not all are beneficial 

loneliness & relationship quality

• loneliness is the discrepancy between a person’s desired and actual social relationships

Xia & Li, 2018: Study of impact of social support on mortality

• in this study, the odds of mortality due to social isolation and loneliness were similar to light smoking (15 cigarettes/day) and alcohol consumption (6 drinks/day), and exceeded the risks conferred by physical inactivity and obesity

• not: top axis: effect size of zero indicates no effect “complex measures” are measures of social integration

physical health & social relationships

• poor social relationships have been linked to

  • 29% increase in risk of incident coronary heart disease

  • 32% increase in risk of stroke

connection between social isolation, stress, and physiological effects

• the hypothalamic-pituitary-adrenocortical (HPA) axis

the hypothalamic-pituitary-adrenocortical (HPA) axis

• hormonal system in the body

• important stress response pathway

• controls circulating glucocorticoid (GC) levels

• social isolation produces increased cortisol levels

glucocorticoids influence the functions of

• glucose regulation

• metabolism

• inflammatory control

• cardiovascular effects

• reproductive effects

• neuronal effects

stress as a determinant of health

• the stress response involves physiological and psychological changes mediated primarily by the hypothalamic-pituitary-adrenal (HPA) axis

systematic chronic inflammation causes & consequences

• isolation and chronic is one of the factors that causes health problems