Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Life Support > Asthma epidemiology > Flashcards

Asthma epidemiology Flashcards

1
Q

What is ‘descriptive epidemiology’?

A

first stage of epidemiological investigation

focuses on describing disease distributions by place, time and person

often based on mortality rates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What levels can geographic variation in health and disease occur?

A

Between countries

Between regions

Between boroughs

Between neighbourhoods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is an ‘ecological study’?

A

a study in which the unit of observation is the population or community
NOT the individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When does an ecological study work best?

A

when there are differences in exposure and disease risks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What factors ARE NEEDED for geographic studies studying disease?

A

causal factor should remain relatively constant in one location

e.g dietary fat, weather, air pollution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do migration studies inform geographic variation for disease?

A

examine whether disease risk reflects the adult environment
or
if its interplay between genes and environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What age demographic usually migrates?

A

people in their 20s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

For migration studies, which individuals are studies for disease risk?

A
  • first generation immigrants

- second generation immigrants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What migration studies were performed for asthma?

A
  • people moving from low to high asthma prevalence locations
  • MIGRANTS: prevalence of asthma increases with duration of time spent in high asthma adoption country to reach levels of host population
  • some studies, prevalence of asthma does not reach host population level until second generation
  • IMPLICATION: strong environmental influence,
    key expo may take an extended period to exert effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the pitfalls of investigating geographic variation for disease risk?

A

Are the differences real?
1. differences in ASCERTAINMENT between countries (willingness to seek medical Rx, ability to obtain it)

  1. differences in DIAGNOSIS
    - local customs or fashion
    - diagnostic equipment
  2. differences in RECORDING info
  3. differences in POPULATION STRUCTURE
    - age
    - gender etc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In geographic studies, how are problems in ascertainment of data overcome?

A

SOLUTION:

  • population wide survey,
  • using objective measures of disease risk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In geographic studies, how are problems in diagnosis or recording overcome?

A

SOLUTION:

- standardise diagnostic criteria e.g. WHO definitions, ICD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In geographic studies, how are problems in population structure overcome?

A

SOLUTION:

  • take account of age and gender
  • stratify data to adjust for these variable to prevent confounding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the special features of the ISAAC asthma study 1998?

A

prevalence of asthma Sx in questionnaire in 14yo

  • population based study
  • standard diagnostic criteria
  • narrow age range
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is are the pitfalls of ecological studies?

A

analysis based on population groups not individuals
Assumption: expo and outcome are also related in individuals, which may not be true = ‘ECOLOGICAL FALLACY’

  • Confounding: since groups may differ from one another in many ways
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the pitfalls of migration studies?

A
  • SELECTION BIAS: are the people who migrated the same as the people left behind?
  • INFO BIAS: do immigrants provide info consistent with non-migrants in surveys?
  • STRESS MIGRATION: can this contribute to disease patterns observed?
17
Q

What should be considered if the geographic differences in disease are real?

A
  • affect prevalence, incidence and mortality?
  • reflect differences in causal factors?
  • reflect differences in clinical prevention or in Rx?
    e. g. screening programmes
18
Q

What levels do time-trends in disease occur at?

A
  • long term trends

- short term (seasonal for eg)

19
Q

What clues can we gain for disease risk from time trends?

A

distinguish whether:

  • recent cause (period effect0
  • early life cause (cohort effect)
20
Q

What is the period effect in disease risk?

A

usually seen in mortality rates

change in all age-groups occurs at the same time point

suggests that there is a cause operating at this time

21
Q

What is the cohort effect in disease risk?

A

usually seen in mortality rates

change in all age-groups related to year at birth

suggests a cause operating from early life

22
Q

How do time trends helot to inform disease risk?

A

assuming trends are real:

  • tell us disease is not inevitable
  • clues for disease causes
  • testing out whether potential causes are important
23
Q

What are the time time trends for asthma in UK?

A
  • do not know why asthma incidences and admissions increased and then fell again 1980s-2000s
  • but we DO know why there was an increase in asthma mortality in 1960s
    • > increase in aerosol inhalers correlates with increased mortality
24
Q

What are the best ways of overcoming confounding in time trend studies?

A

issues: confounding and analyses based on population not individuals

solution: run comparative studies in parallel (expo vs. outcome in individuals)
e. g. cohort, case-control, RCT

25
Q

What basic characteristics are used to assess disease variations in individuals?

A
  • age
  • gender
  • social class
  • ethnicity
26
Q

How does asthma incidence vary with age?

A

high prevalence in pre-school children

decreased prevalence with increasing age

27
Q

How does M/F affect asthma prevalence?

A

children: M > F
Adulthood: F > M

average: similar

28
Q

How can individual variations in health and disease inform us?

A
  • help with diagnosis (stratification by age, sex etc)
  • can provide info on disease causation
  • ID groups who could esp. benefit from disease prevention
29
Q

What is the major pitfall with looking at individual variations in health and disease?

A

some variations represent health inequalities

need efforts to reduce and prevent them

Life Support (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions