The science of pharmacoepidemiology can answer a range of questions regarding how, why, when, where, and by whom a medicine is being used. It is a way of finding out the impact of a medicine as well as the usage results in a large, well-defined population. Also, it can help provide some indication as to how a particular drug is benefitting society and how it may be having a negative impact. Pharmacoepidemiology can be carried out both before and after a medicine is taken to market.

Pharmacoepidemiology takes into consideration disciplines such as biostatistics, computer programming, epidemiology, administrative data, medicine, and pharmacology.

Which organizations use pharmacoepidemiology?

Public health bodies, both national and global, are involved in pharmacoepidemiology. These health bodies include the World Health Organization (WHO), private sector organizations, and drug companies.

The role of pharmacovigilance

Pharmacovigilance, where the impact of a drug is monitored in populations using that particular product, is an integral aspect of pharmacoepidemiology. Organizations can track medicines for evidence of adverse events and safety issues as well as post-marketing activities. Similarly, having this long-term knowledge about a medicine and its impact can help scientists improve its use.

History

Pharmacoepidemiology came to the forefront in the 1960s when the use of antibiotics was being tracked in some European countries.

Also, pharmacoepidemiology was a useful tool when the thalidomide crisis occurred. Scientists noticed a rise in the percentage of abnormalities in infants born to women who were using thalidomide as a treatment for nausea. Pharmacoepidemiology was useful in this case for determining more information.

What is considered in pharmacoepidemiology research?

Pharmacoepidemiology uses clinical epidemiology to examine:

• Benefits and adverse effects
• Drug-drug interactions for patients using more than one medicine
• Medication non-adherence (when patients do not stick to the advised timings and doses of medicines)

Researchers also need to be knowledgeable about the illness that the patients has to enable useful comparisons.

Another area that can be studied in depth is the profile of the doctors that are prescribing a type of medicine. Patterns in education, age, or gender may have an impact on how or what they prescribe.

Other aspects that may influence the use of specific medicines are the location of the doctor or whether the medic is more prone to being an early adopter for new medicines.

Reasons for carrying out pharmacoepidemiology

Post-marketing monitoring of a drug can help scientists discover the efficacy of the medicine as well as its toxicity. Cases of adverse events can be better tracked in the population through the use of pharmacoepidemiology.

Scientists can learn:

• The amount of cases of adverse events
• How a medicine reacts with people who were not involved in previous studies
• The impact of a medicine when combined with other drugs

To generate an awareness of a drug’s efficacy, heterogeneous groups of patients that share a similar age, gender, and comorbidities must be analyzed.

Researchers also have the opportunity to study the outcomes of a medicine in comparison to others on the market for the same disease. Examining a drug’s use in the population can also reveal whether doctors are using the medicine for off-label treatments. With pharmacoepidemiology, scientists may also be able to deduce the impact of an overdose.

In addition to the health impact of a certain drug, economic details can be calculated for health bodies or governments. They can work out the cost per treatment day or the cost in relation to the patient’s income.

References

• http://apps.who.int/medicinedocs/en/d/Js4876e/3.4.html
• http://www.hopkinsmedicine.org/gim/research/content/pharmacoepi.html
• http://www.pharmacoepi.org/pub/1c22d167-2354-d714-511d-5acac8e15615
• http://www.pharmacoepi.org/pub/1c22d167-2354-d714-511d-5acac8e15615
• http://www.slideshare.net/DivjyotKaur/pharmacoepidemiology
• http://apt.med.ubc.ca/files/2013/11/UBC-Pharmacology-400.pdf

Further Reading

• All Pharmacology Content
• Pharmacology
• What is Drug Absorption?
• Drug Distribution
• Drug Excretion / Elimination

Written by

Deborah Fields

Deborah holds a B.Sc. degree in Chemistry from the University of Birmingham and a Postgraduate Diploma in Journalism qualification from Cardiff University. She enjoys writing about the latest innovations. Previously she has worked as an editor of scientific patent information, an education journalist and in communications for innovative healthcare, pharmaceutical and technology organisations. She also loves books and has run a book group for several years. Her enjoyment of fiction extends to writing her own stories for pleasure.