Section 2: 6 Section 1 - Combined Flashcards
What are the issues that epidemiology can address?
Disease Mortality Hospitalization Disability Quality of Life Health Status
What is the numerator used by epidemiologists to calculate disease frequency?
– the number of people to whom something
happened (i.e., they got sick, died, etc.)
What is the denominator used by epidemiologists to calculate disease frequency?
– the population at risk – all the people at
risk for the event
What is three primary sources of data on health and disease in the U.S.?
- The National Center for Health Statistics
- The Behavioral Risk Factor Surveillance System
- Consumer Products Safety Commission
What is a primary source of data on health and disease worldwide?
World Health Organization
Contrast the main units of concern between epidemiology and medicine
For medicine, it’s the individual. For epidemiology, it’s the population.
How does epidemiology differ from public health?
Epidemiology is one of many disciplines that comprise public health. It is a “study of” and public health is an activity.
How does the WHO definition of health differ from the medical definition?
The medical definition is simply the absence of disease, while WHO includes “physical, mental, and social well-being.”
Define morbidity
related to disease or disability
Define mortality
related to death
Define occurrence of disease
prevalence or incidence of disease & health-related conditions
Define endemic
normal occurrence of a condition
Define epidemic
greater than normal occurrence of a condition
Define pandemic
epidemic on multiple continents
How has epidemiology evolved in the 20th century?
transition from acute contagious to chronic non-contagious causes of morbidity; – Morbidity shifted to older age groups and “degenerative diseases”
What were the top 5 causes of death in 1900?
1. Pneumonia / influenza 2 TB 3 Diarrhea 4 Heart disease* 5 Cerebrovascular* * Large % had infectious component
What were the top 5 causes of death in 2009?
1. Heart disease 2 Malignant Neoplasms 3 Cerebrovascular 4 Unintentional Injuries 5 Alzheimer’s disease
What are the main factors for why the main causes of death shifted between 1900 and 2009?
- Medical technology (antibiotics, anesthesia)
- Birth control
- Nutrition
- Sanitation and vector control
- Education
- Improved standard of living
- Many other factors that can’t be over-simplified
How has the demographics of the U.S. populations evolved from 1900 to 2000?
Rather than a consistent decline in the number in each age group (men and women), the largest group is ages 30 to 49, and the number of older men and women is approaching the number of younger people
How did the Age of Enlightenment and Western Civilization affect the study of disease/science?
Science liberated itself from philosophy, morality, and religion
Who is considered the founder of demographics?
John Graunt
What is germ theory?
The idea that disease could be caused by a self-replicating (i.e., biological) agent
When did germ theory emerge?
began in the 16th century but was not accepted until the later part of the 19th century
Before germ theory emerged, what was the primary theory for the spread of disease?
miasma (atmospheric contagion) theory
Who were some early contagionists?
-- Fracastoro (16th century Italian) – Henle & Koch (German physiologists) – Pasteur – Snow – Daniel Salmon (Salmonellosis; vector borne transmission)
Describe the early work of John Snow that established him as a founder of modern epidemiology
Snow was a skeptic of the then-dominant miasma theory that stated that diseases such as cholera and bubonic plague were caused by pollution or a noxious form of “bad air”. His mapping of cholera cases around a public water pump led to removal of a pump handle and curtailment of the disease (before germ theory was established). He conducted ecological, cohort and case-control studies.
What is descriptive epidemiology?
Examining the distribution of disease in a population, and observing the basic features of its distribution
What is analytic epidemiology?
Testing a hypothesis about the cause of disease by studying how exposures relate to the disease
What is descriptive epidemiology most useful for?
- Allocating resources
- Planning programs
- Hypotheses development
What is analytic epidemiology most useful for?
hypothesis testing
What are the three essential characteristics of health-related conditions that we look for in descriptive studies?
- person
- place
- time
What are the aspects of the person that are looked at during descriptive epidemiological studies?
- Age, gender, ethnicity
- Genetic predisposition
- Concurrent disease
- Diet, exercise, smoking
- Risk taking behavior
- SES, education, occupation
What are the aspects of geographic place that are looked at during descriptive epidemiological studies?
– presence or agents or vectors – climate – geology – population density – economic development – nutritional practices – medical practices
What are the aspects of time that are looked at during descriptive epidemiological studies?
- Calendar Time
- Time since an event
- Physiologic cycles
- Age (time since birth)
- Seasonality
- Temporal trends
What are the three essential characteristics that are
examined to study the cause(s) for disease in epidemiology?
– host
– agent
– environment
(the Epidemiological Triangle)
What are the host factors that influence the chance
for disease or its severity?
- Personal traits
- Behaviors
- Genetic predisposition
- Immunologic factors
What are the three types of agents that are necessary for
disease to occur?
Biological
Physical
Chemical
What are the environmental considerations that contribute to the disease process?
- External conditions
- - Physical or Biologic or Social
What are some causes for the host, agent, and environmental factors to get out of balance and cause and epidemic/health status changes?
- new agent
- change in existing agent (infectivity, pathogenicity, virulence)
- change in number of susceptibles in the population
- environmental changes that affect transmission of the agent or growth of the agent
What is epidemiology?
the study of the determinants, distribution, and frequency of health-related events (historically illness/disease) – who gets disease and why?
