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1. Pharmacoepidemiology and drug utilization review By Bushra Khiljee Pharm.D., R.ph, M.Phil. Pharmacy faculty, SIMDC

2. At the end of this learning session you are able to learn

3. Methods of case series study The manufacturer through its sales representatives recruit physicians to participate in the study each participating physician enrolled the patients to whom the drug was prescribed

4. Advantages One can ensure that the patients are typical of those with the drug exposure or with the disease.

5. Limitation In the absence of a control group One cannot ensure which features are unique to the drug exposure , or outcome.

6. 3. Analysis of Secular trends Analysis of secular trends also called “ecological studies”. It examine trends in an exposure (Drug)  that is a presumed to causes ADR and trends in a disease  that is a presumed to effect efficacy and test whether the trends coincide

7. These trends can be examined over time One could analyze data from a single region  and examine how it changes over time.

8. Vital statistics are used for these studies. e.g. one might look at sales data  for oral contraceptives and compare them to death rates from venous thromboembolism.

9. Case 1 Mortality rates from venous thromboembolism  were seen to increase in parallel with increasing oral contraceptive sales in women of reproductive age.

10. Uses Analysis of secular trends are useful  for rapidly providing evidence for or against a hypothesis.

11. Limitations These studies lack data on individuals. They only study group. Thus, among exposures whose trends coincide with that of the disease.

12. Case II: Lung cancer mortality rate in US Lung cancer mortality rates in the US have been increasing in women to extend that lung cancer is now the leading cause of cancer mortality in women. This is consistent with the increasing rates of cigarette smoking observed in women until the mid- 1960s supportive of the association between cigarette smoking and lung cancer.

13. Case Control studies Case control studies are studies which compare: Cases with a disease to controls without the disease.

14. e.g. one could select cases of young women with venous thromboembolism. and compare them to controls  without venous thromboembolism. looking for differences in antecedent oral contraceptive use.

15. Use When one wants to study multiple possible causes of a single disease. When one is studying a relatively rare disease.

16. Challenges Case control studies generally obtain their information on exposures retrospectively i.e. recreating events that happened in the past.

17. The proper selection of controls can be a challenging task. appropriate control selection can lead to a selection bias which may lead to incorrect conclusions.

18. When case control studies are well done subsequent cohort studies or randomized clinical trails will generally confirm their results.

19. Reference Pharmacoepidemiology. Edited by Brian L. Strom., Third edition. Wiley. Page no: 3-24.