Nurs 251- Notes from class- Midterm

Inequality

A non-man made difference

Inequity/disparity

An inequality that is based on some sort of unfair distribution of resources; man made

What is an example of an inequality?

People in Florida get more vitamin D than those in Alaska

What is an example of a disparity?

Resources for low income schools vs high income schools

What does SES stand for?

Socioeconomic status

What are the three guiding principles of health?

1. The choices we make are shaped by the choices we have

2. Most people will make the easiest choices most of the time

3. We need to make healthy choices the east choices

What are the main determinants of health? (4)

1. Biology

2. Environment

3. Health care

4. Lifestyle

What are vulnerable populations?

Groups that are at increased risk for…

1. Developing health problems because of risk

2. Have worse outcomes from health problems compared to the rest of the population

What are some examples of vulnerable populations?

Older people, young people, low income, veteran, pre-exisiting conditions, prisoners, pregnant women

What is the definition of social determinants of health?

the conditions in which people are born, grow-up, live, learn, work, play, worship, and age, as well as the systems put in place to deal with illnesses that affect health and quality of life. These conditions are shaped by a wider set of forces, including economics, social policies, and politics.

What are the big three? (SDOH)

1. Income/education (SES)

2. Race

3. Housing/environment

What is GDP?

A way to describe income/ Gross domestic product (total market value of all goods and services produced by a country)

What is the federal poverty level? (FPL)

Income associated with eligibility for certain government programs

How does low income effect health?

Living conditions, occupational exposure, access to health resources, social capital, personal efficacy, stress

What is guaranteed income?

Once basic needs are met there is a more likely chance that they will get a job and begin to provide for themselves—> relieves stress

What is allostatic load?

The level at which allostatic control mechanism is functioning

How does allostatic load relate to low income?

If the body is in a chronic state of stress, there is no opportunity to recharge and cannot respond to new stressors'; Low SES is associated with elevated biomarkers and cardiovascular disease

What are the effects of chronic elevation of cortisol/other stress hormones

Trigger inflamation in cells and release of inflammatory cytokines

“Diseases of affluence”

Those with high SES likely to engage in unhealthy behavior; has some truth but not completely; lifestyle not often freely chosen

Epidemiology definition

The study of how disease (or injury) is distributed in populations and the factors that influence or determine this distribution

What are the components of the epidemiological perspective (4)?

1. focus on populations, multiple episodes of illness

2. describe history of present illness

3. observe patterns- who, what, where, when

4. Implement preventive measures

Epidemiologic variables (3)

Host, agent, and environment

What is the agent?

The factor that is necessary for disease to occur

Can be biological, physical, or chemical

Does the agent need to be present?

NO; can be a result of presence, absence, or relative (kinda conflicting idk if this is right)

What are the characteristics of an agent? (4)

1. Infectivity (being infected)

2. Pathogenicity (versus being ill)

3. Toxicity or virulence (severity of disease)

4. Antigenicity (the ability of the agent to attach to our immune response and overcome it)

What is an example of an agent?

HIV; does not necessarily cause the disease but creates that possibility

what does it mean if an agent is necessary and sufficient?

Must be present and always leads to disease (down syndrome)

What does it mean for an agent to be necessary but contributory?

Must be present, but only works with other factors (HIV)

What is the host?

The individuals in whom disease is occurring and the intrinsic (non-modifiable and modifable)

What characteristics of the host effect the likelihood of exposure/effects? (7)

1. Genetic background (ex; sickle cell)

2. Nutritional status (scurvy and rickets)

3. Immunological characteristics

4. Age

5. Gender

6. Comorbidities

7. Behavior/lifestyle

What is the environment?

The external conditions that contribute to disease either by increasing host exposure and susceptibility, or by affecting the agents transmissibility, infectivity, and virulence

What are environmental factors? (7)

1. Climate (temp and humidity)

2. Geography

3. Flora and fauna

4. Water (amount and quality)

5. Air quality

6. Altitude

7. Social conditions (crowding and housing)

What is epidemiological homeostasis?

The ecological balance of agent, host, and environmental conditions that result in a “usual” or endemic amount of disease in a population

What is an example of something endemic to the US?

The flu

What does a change in epidemiological homeostasis result in?

Epidemic, pandemic, or disease reduction or eradication

What are reservoirs for disease?

The normal habitat in which an infectious agent lives, grows, and multiplies

What are examples of reservoirs for disease?

Symptomatic cases; carries; (incubatory, asymptomatic, or convalescent); insects and animals; inanimate objects

What is a vector?

An animal that carries a disease

What are the main portals of entry and exit?

1. respiratory tract (pneumonia, covid, flu)

2. Gastrointestinal tract (salmonella, food poisoning, ecoli)

3. Urogenital tract (STDs)

4. Skin (Malaria, protozoa)

5. Conjuctiva

6. Placenta (in womb to fetus)

What are the 5 modes of transmission?

1. Horizontal

2. Vertical

3. Common vehicle

4. Vectors

5. Phomite

What is horizontal transmission?

Person-to-person through direct contact, airborne

What is vertical transmission?

From parent to offspring (via placenta, semen, breastmilk, infected birth canal)

What is common vehicle transmission?

Transportation via food, water, milk, blood, air

What is vector transmission?

Insects or animals that transmit the agent to the host

What is phomit transmission?

Nonliving mode of transmission

What are the 5 disease patterns?

1. Point source outbreak

2. Common source outbreak

3. Mixed source outbreak

4. Intermittent or continuous source outbreak

5. Endemic or Epidemic

What is a point source outbreak?

All cases became ill at the same time

What is a common source outbreak?

All cases exposed to the same noxious influence, but timing of onset can vary

What is a mixed source outbreak?

Common source plus secondary exposures

What is intermittent or continuous source outbreak?

Occurs over a prolonged time from the same source

What are the 4 modes of resistance (immunity)?

1. Natural immunity

2. Acquired immunity

3. Passive immunity

4. Herd immunity

What is natural immunity?

Species determines, innate resistance

What is acquired immunity?

natural or induced; have to do something to get it

What is passive immunity?

Person given antibodies to a disease rather than producing them through his or her own immune system; ex: breastmilk and placenta

What is herd immunity?

Immunity of a group or community; resistance of a group to invasion of an infectious agent due to resistance of a high proportion of group members (can vary by disease)

What is the natural progression (history) of disease

Stage of susceptibility—>exposure—>infection→incubation period/prodromal—> Diagnosis—>Convalescence and resolution

What is descriptive epidemiology?

Measuring and describing the occurence of disease

What is incidence?

number of new cases that occur during a specific time frame in a population at risk for developing the disease

How do you measure incidence?

Number of new cases during X time/ Number of persons at risk/ Exposed during X time

What is prevalence?

The proportion of the population affected by a disease at a specific point in time

How do you measure prevalence?

Number of cases present in pop. at time X/ Number of persons in pop. at X time

What is incidence affected by?

Symptoms, diagnosis, changes in agent, changes in environment

What is prevalence affected by?

incidece, detection, cure rates, survival rates

What does incidence estimate?

Risk of disease if exposed (odds) and the speed at which the disease is spreading

What does prevalence describe?

Disease burden in a community

How do we describe the prognosis of disease?

Survival rate, median survival time, relative survival time, life tables, mortality rate

What is analytic epidemiology?

Identifying causes of health and illness

What are the questions of interest for analytical epidemiology?

• What is the risk of disease, given a certain exposure?

• Does exposure increase risk, compared to non-exposure

• If there is a positive association between exposure and disease, is the association causal in nature?

• How much disease could be avoided by eliminating exposure, if this is possible and feasible?

What is the criteria for causality (8)?

1. Correct temporal sequence between exposure and disease

2. Strength of association

3. Dose-response relationship

4. Consistency of findings across populations and studies

5. Biological plausibility

6. Cessation of exposure leads to cessation of outcome

7. Relationship parallels other observations

8. Alternative explanations for outcome can be ruled out

What are two applications of analytical epi.

Identifying cause of disease and determining the effectiveness of interventions

What are the options for study design in analytical epidemiology? (5)

1. Ecological studies

2. Cross-sectional studies

3. Case control studies

4. Cohort studies

5. Experimental studies or community trials

What is an ecological study?

Bridge between descriptive and analytical epi.

Look at variation in disease by person, time, and place

Use population-level or community data

What are the pros of ecological studies?

Quick and inexpensive

can use existing data

What are the cons of ecological studies?

Prone to ecological fallacy- assigning group characteristics to individual group members

What are some examples of ecological studies?

• Comparing breast cancer rates across nations

• Link between poverty and heart disease

• Link between access to fresh produce and prevalence of diabetes

What is a cross sectional study?

Information is collected from individual group members about both exposure and disease (history or presence) at one specific point in time

Allows comparison of disease prevalence according to exposure (or exposure to prevalence and according to disease)

What are the pros of cross sectional studies?

Easy and cost effective

What are the cons of cross sectional studies?

Subject to recall bias, bias from self-reporting

Timing between exposure and outcome may be uncertain

Subject to bias from selective survival- does not include those who died from disease

May show relationship to exposure to survival, not disease development

Cannot calculate incidence or risk

What is a case control study?

Subjects are enrolled on the basis of their confirmed disease status and then information is collected about exposure

What are the pros of case control studies?

Requires smaller sample sizes because outcome of interest has already occurred

!!! Allow calculation of Odds ratio, between cases vs control

What are the cons of case control studies?

sampling bias; how cases are recruits and defined

Bias r/t selective recall of exposure

Disease has already occurred, cannot say what caused the disease can only compare data between one with and one without (no incidence)

What is the odds-ration

Likelihood of exposure

what does and OR>1 mean?

Exposure is more likely in cases

What does and OR<1 mean?

exposure is less likely in cases

CALCULATIONS

STUDY IDK HOW TO WRITE THEM OUT ON THIS SHI

What is a cohort study?

Start with knowledge of exposure status and follow overtime to determine occurrence of disease

What are the pros of cohort studies?

Can see when disease develops in relation to expousre

!!! allow calculation of incidence and relative risk (RR)

What are the cons of cohort studies?

May require large samples if disease is rare

Some diseases take a long time to develop

Definition of a case may over time

What is relative risk (RR)

Risk for developing disease for exposure versus not exposed group

CALCULATIONS FOR RR

ON NOTES IDK HOW TO WRITE IT HERE

Experimental studies

Experiments; best for determining causation

What constitutes a poor neighborhoods?

20% of residents are poor

What is the deprivation amplification?

People with less income and education end up living in neighborhoods with impoverishes “opportunity structures” such as schools, libraries, employment opportunities

Why is it hard to escape health-damaging physical and social environments?

Lack of resources that can lead to upward mobility, fewer positive role models, fewer community members with resources to provide a “leg up”

How do conservatives respond to poverty?

Individualism

How do liberals respond to poverty?

Social responsibility

What is a disordered neighborhood?

poorly functioning public services, graffiti, crime

How do disordered neighborhoods effect residents?

They have a sense of powerlessness, more stress, and engage in more risky behavior

What is stress associated with?

Emotional disorders and destructive behavior

How does neighborhood stability effect residents?

Provide a sense of identity and belonging; less stress