Social Epidemiology Exam 2

Methods, Social Networks, Social Relationships, Physical Environments and Health

Observational Study Branch

Descriptive and Analytical → cross-sectional study, case control study, cohort study

Descriptive Epidemiology

study of the occurrence and distribution of disease

Must: 1 Generate hypotheses, 2 Asks: who, where, when, 3 Used when little information is known about the disease, 4 relies on data that already exists, 5 illustrates potential associations

3 Goals:

1 evaluate trends in health and disease, and allow comparisons among countries and subgroups withing countries

2 provide basis for planning, provision, and evaluation of health services

3 identify problems to be studied by analytic methods and suggest areas that may be good to investigate

Analytic Epidemiology

studies that evaluate hypotheses to search for causes and effects

Must: 1 test hypotheses, 2 asks: why and how, 3 used when information about the disease is available, 4 relies on development of new data, 5, evaluates causality of associations

3 types: cross-sectional, case-control, cohort

Experimental epidemiology

provide scientific proof of etiological factors that may allow for the modification or control of a disease (etiological: causing or contributing to the development of a disease or condition)

2 types: randomized controlled trials and community & field trials

Cross-Sectional Study

measures the prevalence of health outcomes or determinants of health, or both, in a population at a point in time or over a short period of time

difficult to establish causality

retrospective study

ex. neighborhood poverty and depression - measured all at once

Case-control study

selects and compares the cases to the controls; looks back in time to learn which subjects in each group had the exposures, comparing the frequency of the exposure in the case group to the control group

selects subjects based on their disease status

retrospective study

ex. housing instability and suicide attempts - start with outcome then look back at exposure

Cohort study

subjects are followed over time with continuous or repeated monitoring of risk factors or health outcomes, or both

prospective study

ex. childhood adversity and adult heart disease: measured with start and end

Randomized controlled trials

study design that randomly assigns participants into an experimental or control group. addresses the efficacy of an intervention (ex. chemotherapy trial to treat cancer)

only expected difference between the control and experimental groups is the outcome variable being studied → does NOT reveal causation but is the closest thing (too much error to be accounted for)

Community and field trials

non-randomized experiments that are based on deliberate criteria built into the study

field trials: address preventative interventions applied to individuals (ex. vaccine trials)

community trials: address the efficacy of preventive interventions applied at the group level (ex. a social marketing campaign trial)

Multilevel methods and modeling

methodology that allows for simultaneous analysis of the effects of individuals and the effects of contexts - makes it very important for social epi, but contexts can vary

What levels are Sampson et al. looking at

within person, within neighborhood, across neighborhoods

Why do Sampson et al. models need to include both levels

because both individual and group dynamics effect neighborhood and collective efficacy

Collective efficacy definition - why can’t it be studied at the individual level

the perceived and enacted capacity of a group to work together - in nature is group defined

How do epidemiologists define cause

cause is a factor that plays a role in producing an occurrence of the disease

not necessarily part of the disease process

something proceeding a disease or illness without which the disease would not have occurred or would have occurred at a later time - direct or indirect role in causing the disease

what are the causal inference guidelines for

process of deriving cause-and-effect conclusions by reasoning from knowledge and factual evidence → requires strong conceptual models founded in theory → association must be observed and causality is not proven by any one study

1 RCT evidence exists

2 no alternative explanations exist (no confounding)

3 timing of the relationship is correct

4 association is strong

5 association is biologically plausible

6 higher exposures lead to higher risks

7 observed evidence is consistent

Confounding

when a correlation between two measures is actually driven by a third variable not included

Oakes (2004) critique surrounding confounding in studies on neighborhood effects

• Reviewed studies that examined the causal effect of neighborhood contexts on health

• Oakes argued that research on neighborhood effects on health was lacking because of the issue of structural confounding

  • There were not enough people in each stratum of confounding measures when looking at health outcomes between different neighborhoods

Morbidity

presence of disease in a population

Mortality

occurrence of death in a population

Incidence

number of new cases of disease that develop in the population during a defined period

Prevalence

number of existing cases of disease in the population during a defined period

Economic Capital

amount of monetary or exchange value a person possesses

Cultural Capital

refers to a person’s cultural competencies

Social Capital

refers to the network of relationships and acquaintances that a person has developed over their life

Objective components of social capital

(structural elements)

financial support

providing care-taking resources

actual provision of assistance when in need, help when sick

looking out for one another

law enforcement

community medical and social welfare services

Subjective components of social capital

(cognitive elements)

emotional support

friendship

love

feelings of well-being, comfort, safety

Social capital and health at the individual level

health resources accessed by the individual through their social network

ex. information (where to get free flu shot), instrumental support (cash loan), social reinforcement of behavior

Social capital and health at the group level

as a property of the whole social network, social capital can bring benefits to individuals embedded in it

3 mechanisms are:

Social contagion:

informal social control:

collective efficacy:

Social contagion

behaviors, emotions, ideas, and information spread more quickly a tightly knit social network

ex. transmission of behavioral norms (good or bad)

Informal Social control

ability of adults in a community to maintain social order (to step in and intervene when they witness deviant behaviors by others)

originally used to explain ability of community to suppress crime - also relevant to prevention of negative health behaviors: smoking, drinking, drug abuse

Collective Efficacy

ability of the collective to mobilize to undertake collective action

In all processes, the individual benefits from their connection to a group

social capital can also benefit people beyond the network - positive spillover effects

Bonding vs Bridging social capital

Bonding: resources that are accessed within networks or groups in which the members share similar background characteristics (race, ethnicity, class)

Bridging: resources that are accessed across networks that cross class, race, ethnicity or other characteristics

Dark Side of social capital

down-leveling of norms

in-group solidarity to exclude out-groups

expectations of conformity; intolerance of diversity

excessive claims made on group members

Fowler and Christakis’s findings regarding happiness spreads in social networks? How far/degrees does happiness appear to spread? How do proximity and time matter?

• Happy people tend to be connected to one another

• The better connected are one’s friends and family, the more likely one will attain happiness in the future

• Each additional happy alter increases the likelihood of happiness, but each additional unhappy alter has little or no effect

• The principal determinant of a person’s happiness was their previous happiness

• Happiness requires close physical proximity to spread and the effect decays over time

• 3 degrees removed from social network

How do social relationships influence health? How does the effect of social relationships on mortality compare to the effect of smoking, drinking, or physical activity on mortality?

behavioral, psychosocial, physiological

the effects of social experiences accumulate through life, so that health risks increase as someone has continual social difficulties

policy-makers can use the educational system to reduce social isolation in America

improving social ties is a cost-effective preventive medicine strategy

• Studies have shown the benefit of a network of social support, including the following:

  • Improving the ability to cope with stressful situations

  • Alleviating the effects of emotional distress

  • Promoting lifelong good mental health

  • Enhancing self-esteem

  • Lowering cardiovascular risks, such as lowering blood pressure

  • Promoting healthy lifestyle behaviors

  • Encouraging adherence to a treatment plan

How does marriage matter for health and how is it different for men and women?

Marriage is generally good for health, and the health effects are greater for men than women

better to be happily single than unhappily married

Social support vs social integration vs social isolation

social support: refers to resources that people receive from their social relationships and social networks and their membership of groups

social integration: refers to the degree and strength of social bonds within the society

social isolation: refers to pervasive lack of social contact or communication, participation in social activities, or confidant

Recent trends in levels of social support and social isolation

more social isolation, less social support

What is built environment? What are examples of it? What are some ways it impacts health?

human made or modified spaces, surroundings in/around which people live, work, and recreate, or spend time

ex. cities, parks/green spaces, transportation systems, resources and amenities, food availability, housing, sewage and sanitation systems

Transportation: air pollution and respiratory health, climate change, injuries (cars, bikes)

Land Use: obesity, physical activity, CVD, access to resources, schools, healthy food outlets

Infrastructure: water quality, quantity, sanitation

Social Structure: mental health, relationships/social capital, health inequalities

What do Lovasi et al. find about obesity difference in their 3 focus groups regarding: the food environment, urban form, and places to exercise?

Food environment very important in association with obesity: proximity to supermarket is associated with less overweight, obesity, and hypertension - proximity to convenience stores association with more overweight, obesity, hypertension, and diabetes

Urban Form: walkable neighborhoods support physical activity and lower BMI - urban sprawl hinders physical activity and promotes obesity - national study found children in denser areas were more likely to have an active commute regardless of race/ethnicity - low income, black, Hispanic population more so reside in areas with higher population density and less sprawl

Places to exercise: some evidence that well-maintained sidewalks, trails, and exercise facilities may support physical activity for 3 targeted groups - physical activity is a good stress reducer - trails more common in high - SES areas, and low-income groups perceived less access to indoor and outdoor places to exercise

BIG 3: Supermarket access, exercise facilities, safety

Walkability and bikeability - how are they related to health?

Greater walkability: lower rates of obesity, increase physical activity, lower rates of depression, higher social capital, less alcohol and drug use

Bike ability: refers to the access that an area has granted to safe biking through multiple bike paths and bike lanes - lower BMI, lower overweight risk, higher physical activity

Food access (food deserts, food swamps, food insecurity) and health

Proximity to grocery stores and community gardens - a higher density of convenience stores has been associated with obesity in children

food deserts: describes neighborhood and communities that have limited access to affordable and nutritious foods - urban and rural low-income neighborhoods

food swamps: neighborhoods or geographic areas with a greater concentration of outlets that sell less nutritious foods, such as fast food and snacks, than outlets with more nutritious minimally processed options - stronger predictor of obesity than a food desert

Food insecurity: lack of access, at times, to enough food for an active, healthy life (drivers: unemployment, poverty, income shocks)

How do Cohen et al. apply broken windows theory to study STI rates? What do they find?

Broken windows: physical environment is a consequence of neglect and a signal that behaviors which are usually prohibited are tolerated

• Broken Windows measures

  • Drove though neighborhoods to assess level of damage (structural vs. cosmetic damage, garbage, graffiti, abandoned vehicles)

  • Physical plant inspections of public schools (problems with building, play area, toilet facilities, handling of social waste, drinking fountain water supply)

• Only broken windows remained significantly related to gonorrhea rates

• Marital status and off-sale alcohol outlet density had marginal but effect on gonorrhea rates

• Combination of both

“With progressive neighborhood deterioration, families with means and traditional standards of behavior often leave the area or the city. When persons with traditional values leave, possible role modeling or controlling factors…that might have otherwise served to reduce the high-risk behaviors disappear. Norms of the street begin to prevail in the absence of counterbalancing forces”

Physical vs social disorder in neighborhoods and how this is related to chronic stress

• Physical disorder

  • Abandoned buildings

  • Noise

  • Graffiti

  • Vandalism

  • Filth

  • Disrepair

Social Disorder

• Crime

• Loitering

• Public drinking or drug use

• Conflicts

• Indifference 

Methods: Sampson, Robert J., Stephen W. Raudenbush, and Felton Earls. 1997. “Neighborhoods and Violent Crime: A Multilevel Study of Collective Efficacy.” Science 277:918-924.

Purpose: to test whether neighborhood collective efficacy (social cohesion and shared willingness to intervene) explains variation in violence, beyond concentrated disadvantage and residential instability

methodology: Chicago neighborhood clusters - individual and community levels looked at

Results: collective efficacy was strongly and negatively associated with violence, and it partly mediated the effects of concentrated disadvantage and residential instability - held after controlling for individual characteristics and prior violence, and for neighborhood composition

Social networks and social relationships: Fowler, James H., and Nicholas A. Christakis. 2008. "Dynamic Spread of Happiness in a Large Social Network: Longitudinal Analysis over 20 Years in the Framingham Heart Study." BMJ 337:a2338.

Purpose: evaluate whether happiness can spread from person to person and whether niches of happiness form within social networks

Contribution: studied effects of happiness of others - other studies looked at other stimuli to happiness but this one looked at others on us

Methodology: longitudinal social network analysis - framington heart study social network - 4739 people from 1983 to 2003

Main findings: happy people tend to be located in the center of their social networks and in large clusters of happy people - happiness of an individual is associated with happiness of people 3 degrees removed from network

Social networks and social relationships: Umberson, Debra, and Jennifer Karas Montez. 2010. "Social Relationships and Health: A Flashpoint for Health Policy." Journal of Health and Social Behavior 51(1_suppl): S54-S66.

Purpose: key research themes in the study of social relationships and health, highlighting policy implications

Contribution: policy implications

Methodology: review article

Main findings:

social relationships have significant health effects

social relationships affect health through behavioral, psychosocial, physiological

relationships have costs and benefits for health

relationships shape health outcomes throughout the life course and have a cumulative impact on health over time

costs and benefits of social relationships are not equally distributed in the population

Social networks and social relationships: 1.     Holt-Lunstad, Julianne, and Carla Perissinotto. 2023. "Social Isolation and Loneliness as Medical Issues." New England Journal of Medicine 388(3):193-195.

SIL increases risk of many serious medical issues including CVD and death from any cause

rivals obesity in death risk

effects c-reactive protein and fibrinogen levels

correlates with health disparities

recommends all patients evaluated for SIL

EAR - Educate about social connection, Assess document SIL in health records, Respond integration and reinforcement (framework for addressing SIL)

Physical environments: Cohen, Deborah, Suzanne Spear, Richard Scribner, Patty Kissinger, Karen Mason, and John Wildgen. 2000 ""Broken Windows" and the Risk of Gonorrhea." American Journal of Public Health 90(2):230.

Purpose: to examine the relationships between neighborhood conditions and gonorrhea

Methodology: broken windows index - housing quality, abandoned cars, graffiti, trash, and public-school deterioration

results: broken windows index explained more than the poverty index, block groups with higher broken windows scores had higher rates of gonorrhea - environment plays a role independent of poverty

Physical Environments: Lovasi, Gina S., Malo A. Hutson, Monica Guerra, and Kathryn M. Neckerman. 2009. "Built Environments and Obesity in Disadvantaged Populations." Epidemiologic Reviews 31(1):7-20.

purpose: understand obesity related health disparities might relate to obesogenic built environments

main findings/contribution: supermarket access, exercise facilities, safety

food stores, places to exercise and safety

proximity to food stores not restaurants or convenience stores

supermarkets best - cheapest and high-quality produce

walkability not associated with BMI among target population, access to physical exercise through - mixed evidence

methodology: 1 low SES, 2 Black, 3 Hispanic Latino - systematic literature review

3 strongest features:

Supermarket

exercise facilites

safety

Physical Environments: Ross, Catherine E., and John Mirowsky. 2001. "Neighborhood Disadvantage, Disorder, and Health." Journal of Health and Social Behavior 42(3): 258-276.

Purpose: to examine if living in a disadvantaged neighborhood is damaging to health beyond the impact of individual SES characteristics

Contribution/Main findings: residents of disadvantaged neighborhood shave worse health than advantaged neighborhood - mediated entirely by perceived neighborhood disorder and resulting fear - daily stress of living there damages health, little effect on walking or other health behaviors

methodology - 1995 community, health and crime survey - 2482 adults in Illinois, multilevel data - physical health as dependent variable

high rates of poverty and single mother households, physical or social disorder, did not find mediation between lack of outdoor access and health behaviors, more physical and chronic health problems