Epidemiology of lung disease Flashcards
What is epidemiology?
The study of how often diseases occur in different groups of people and why
How can epidemiology be used?
To plan and evaluate strategies to prevent/ameliorate illness
What is incidence?
The rate at which new cases occur in a population during a specified time period
e.g. number of new cases per 1000 PER YEAR
What is prevalence?
Proportion of a pollution that have a disease at a point in time
What type of conditions is prevalence best for?
stable ones, NOT acute ones
How do improvements in care affect prevalence?
Prevalence increases as death rate is lower, so more people are living with the disease at any one time
Define mortality
Incidence of death from a disease, measured in no. per amount of people per year
What are the advantages of ecological studies?
Cheap
easy to perform
data readily available
What are the disadvantages of ecological studies?
Subject to bias and ecological fallacy
Is case control retrospective or prospective?
retrospective
What does a cross sectional study measure and why?
Prevalence - the study is done at one moment in time and people with the disease and with the disease are compared to see whether certain factors are present or absent in the disease or non-disease group
What does a cohort study measure and why?
incidence - follows one group that has been exposed and another group that hasn’t’ been exposed over time to find out who develops the disease
Give an example of a type of intervention study design
RCT
What two diseases make up COPD?
Emphysema and chronic bronchitis
How do we define chronic bronchitis?
cough with sputum for 3 months for 2 or more consecutive years
What is the FEV1/FVC for COPD?
<70%
What is a bed day?
a day during which a person is confined to a bed and in which the patient stays overnight in a hospital
What is the main cause of COPD
smoking
What famous study was done on smoking in the UK from 1951-2001 and who did it and what did they find?
British Doctors Study done by Doll and Bradford Hill
done on nearly 35,000 male doctors and found the smokers die 10 years early in a dose response fashion, so a prospective study
What proportion of COPD is caused by work?
15%
Give examples of causes of COPD in the workplace
coal dust silica cotton grain cadmium isocyanates welders joiners construction workers
Give one genetic cause of COPD
alpha 1 antitrypsin deficiency
Give examples of environmental causes of COPD
tobacco smoke
air pollution
Give reasons for geographical variations in COPD
socio-economic
housing and nutrition
historic industry (e.g. coal mining)
increasing smoking prevalence
