Pharmacoepidemiology

epidemoilogy study

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PRESENTED BY
ASHUTOSH B. MAHALE
M.PHARMACY FIRST YEAR ( PHARMACOLOGY )
UNIVERSITY DEPARTMENT OF PHARMACEUTICAL
SCIENCES, R.T.M NAGPUR UNIVERSITY , NAGPUR

2. Pharmacoepidemiology is the study of use and effect of drugs
in large no of people
PE is the application of principles of epidemiology to drug
effects and drug use
The term pharmacoepidemiology contains two components
“pharmaco” and “epidemiology”
Pharmaco means drug & epidemiology means study of
distribution and determinants of disease in a population
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PHARMACOEPIDEMIOLOGY
Pharmacoepidemiology is the study of use and effect of drugs
in large no of people

3. Epidemiology has two major areas- one is the study of
infectious disease in large population called epidemics and
the second is the study of chronic disease
PE involves gathering & analysis of information in order to
identify possible causation & related factors that can be
applied in clinical practice to group of people &also
individual undergoing treatment
So it examines the relationship b/w drug exposure & health
outcome in a defined population
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NEED - Since PE is considered as a science of understanding of
medicine safety issues, all those who use, prescribe, study,
Monitor or deal with medicine at academic ,research or
regulatory level need PE

6. Lack of alternative models to investigate some drug events
Eg.to evaluate the teratogenic effect of a new medicine
 CTs are inadequate to answer to questions about drug safety
as they lack adequate statistical power
If at all adequate for establishing effectiveness, the sample
Size of peoples are inadequate to detect less common ADR
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7. CTs are conducted on highly selected patients without any co-
morbidities and who taking no other medications.
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CT does not involve elderly paediatric or pregnant patients.
CT investigates the single indication
Hence CT fail to provide adequate information related to
safety and efficacy of a drug under non trial condition.
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In contrast, PE models provide alternative approaches to
evaluate drug effects
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8. The pharmacoepidemiological studies concentrate on the
period after the drug enters the market known as post
marketing surveillance (PMS)
These studies are concerned with two main aspects:
1. the study of adverse effects of drugs
2. the appropriate use of medicines
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•Case Reports:-
A case report describes the effects of
the drug a single patient experiencing.
Case reports are easy and cheap
method for generating hypothesis about drug effects

•Case Series: -
Case series are collection of patients who
had single exposure. Case series are useful in quantifying the
incidence of ADRs

•Analyses of secular trends (Ecological Studies):-
Analysis of data from a single region
and examine how it changes over time.
They are useful to provide rapid evidence
for hypotheses
Epidemiologic Study Designs

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• Case-control study:
These studies compare cases with disease to
controls without disease.
Useful to study multiple
possible causes of a single disease. Useful to
study uncommon diseases.
It is easier and faster to conduct Case-control study.
It is less expensive

•Cohort study:
Cohort studies identify subsets of a defined
population and follow them over time, looking for differences
in their outcome.
They are useful to compare exposed patients to
unexposed patients.
Can study multiple outcomes.
Can study uncommon exposures

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•Randomized clinical trials (Experimental Studies):-
In randomized clinical trials, the investigator
controls the therapy to be received by each participant
Most convincing design
Most expensive
design
It is an artificial design
Logistically most difficult

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ESTIMATION OF RISKS OF DRUG USE :
The risk involved in drug use can be quantified
The benefits & risks of use of a drug may be weighed
Risk estimation also helps to identify risk situation
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13. USE IN PATIENT COUNSELING:
Collection & analysis of observational data from other studies may
help to address certain issues through counseling the patients
Ex:
A pregnant patient may wish to terminate pregnancy if there is a
substantial risk for producing a seriously malformed child, but would
also wish to proceed with the pregnancy if the risk is low

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14. Ex:
Case reports of triazolam induced psychiatric disturbances
appeared soon after its introduction to market
The drug was withdrawn in some countries
The reaction was likely due to dose related, hence the
problem was abated by recommending a lower dose
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15. FORMULATION OF PUBLIC HEALTH POLICY
DECISIONS:
Qualitative as well as quantitative information from PE studies helps
to address many issues
Ex:
If an inappropriate prescribing is observed among prescribers,
regulatory agencies may require educational intervention or may
impose restrictions on specific drugs or on practition
PE studies also helps the policy makers to assess whether a
drug should be withdrawn from the market or allowed to
remain
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16. FACILITATION OF PHARMACOECONOMICS
EVALUATIONS
Data from PE studies can be used to measure the effects of
drugs on overall health care costs & resource consumption
Ex:
Hospitalization due to serious adverse effects of a drug leads
to more expenses as well as resource consumption, which
could be avoidable.
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•Spontaneous AE reporting
•Global Drug surveillance
•Case- control surveillance
•Prescription event monitoring
•Automated databases
•Others
Sources of PE data

18. Age based medicine use and it’s analysis.
2. Generation of data bases for other studies
3. Pharmacovigilance
4.drug usage analysis
5.empowering pharmacogenomic studies
6.evaluation of hospital committees
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• Evaluating and improving physician prescribing

•Drug Utilization Review

•Special methodologic issues in PE studies of Vaccine Study

•PE studies of Devices

•Studies of Drug-induced birth defects

•PE and Risk management

•Use of PE to study Medication Errors

•Hospital Pharmacy

20. Can be useful in many cases where other models cannot
Allow quantification of drug effects in special
population/patients with co morbid conditions & patients who
are on polypharmacy
Allows quantification of drug effects in a more realistic
environment
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21. Serve as alerting mechanism for clinicians, manufacturers and
regulatory authorities
Also serve as signal generators which further directs towards
research and indicate new areas to explore
Allows comparison of drug use patterns between areas
Quantification of DRPs
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Allows rational use of drugs
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22. These are non-experimental studies
Some times Causation may be difficult
Confounding factors, biases (like selection, informational)
may threaten the validity
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THANK YOU