Epidemiological study
Epidemiology: Why are epidemiological studies used?
Determines the cause of
disease and which
populations are
affected
Guides the development of
strategies to control disease
and improve public health
Evaluates the effectiveness
of strategies in place to
treat/control disease
Analysis of data allows the identification of patterns
and trends in the incidence, prevalence and mortality
rates of disease
Analysis of Data to Determine Population Affected
Incidence = number of new cases occurring during
a time period (usually one year) per 100,000
population
Comparison of colorectal cancer between Indigenous and non-Indigenous populations.
Even though the incidence rate is only slightly higher for non-indigenous populations, when you examine the mortality
rates (graph on right) you can see the mortality rate is much higher for non-indigenous populations
Incidence rate = number of new cases / number of
persons at risk during a specified time (usually one
year)
Age standardised rate = measure of what the rate
would be if the population had a standard age
structure. Used to compare populations from
different countries or regions
Prevalence = the number of people in a
population that have been diagnosed with the
disease AND are still alive (new + existing cases) at
the end of a time period
Mortality rate = number of deaths due to a
particular disease in a specific time period (usually
one year) per 100,000 population
Graph: Prevalence of diabetes mellitus (type I)
2014-2015
Look at the Y axis - % of total Australian
Population
The prevalence of diabetes mellitus is 6% higher
for males in the 65-74 age group than it is for
females in the same age group.
Epidemiology: Helps to develop strategies to
control disease
Future Directions
1. Restoring beta cell function by
blocking protein VDAC1
2. Artificial pancreas
3. Brown fat cells
Medications:
Metformin - works by lowering glucose production in the liver and
improving your body's sensitivity to insulin so that your body uses
insulin more effectively.
Sulfonylureas. These medications help your body secrete more
insulin. Examples include glyburide (DiaBeta, Glynase), glipizide
(Glucotrol) and glimepiride (Amaryl).
Evaluate effectiveness of strategies to control disease
Make a judgement based on criteria using evidence to support the
judgement.
The method used in the study should follow accepted
epidemiological principles. Errors should be included in evaluation.
Criteria common to most epidemiological study include: large
sample size, long period of study, using scientifically approved
methods of implementing the study, collecting data and analysing
the results.
Lund University – blocking a protein VDAC1 in the betaproducing cells may restore their function. It might also
be used in pre-diabetic patients to prevent onset of Type
II. https://medicalxpress.com/news/2018-10-discoveryinsulin-cell-function-diabetes.html
Research being funded by the American Diabetes Association – to find out how the brain
switches on and off brown fat cells. Brown fat cells generate heat to maintain optimal
body temperature. These cells use large amounts of glucose to drive this heat production, thus
serving as a potential way to lower blood sugar, a key goal for any diabetes treatment.
Methods used in Epidemiological Studies:
Descriptive Studies: collect information about the frequency of the disease, population affected,
location and time, and hypotheses are proposed from this.
Analytical studies: collect and analyse data
Types of Analytical Studies:
-
Case control studies- compare people who have the disease (cases) with people who do not
have the disease (controls)
Cohort studies – study two or more similar groups who are free of the disease. One group is
exposed to the possible cause of the disease while the other is not.