PHARMACOEPIDEMIOLOGY - Introduction, Aim, souce of data, Types, Epidemiologic study design and Applications
- 1. PHARMACOEPIDEMIOLOGY PRESENTED BY- RITIK SHARMA M.PHARM. 2nd sem. (PHARMACOLOGY) ROLL NO.- 2441121
- 3. INTRODUCTION Pharmacoepidemiology is the study of the use and effect of drugs in large number of people. It is a growing discipline that applies epidemiological techniques to study drug use in a large population. It is the bridging between clinical pharmacology and epidemiology. Pharmacoepidemiology is so called because it combines principles from both pharmacology and epidemiology. It provides an estimate of the probability of beneficial effects of a drug in a population and the probability of adverse effects.
- 4. Pharmacology is the study of the effects of drugs Clinical Pharmacology is the study of effects of drugs in humans Epidemiology is the study of the distribution and determinants of disease in populations Pharmacoepidemiology is the study of the use and effects of drugs in large number of people.
- 5. Aim •WHO targets its pharmacoepidemiological efforts to ensure the quality, safety, and efficacy of drugs. •The studies focus on -Global trends in prescribing -Medication adherence -Lifestyle effects on drug therapy -Drug interactions -Predictable ADRs -Uncommon and unpredictable ADRs
- 6. Sources of data • The source of drug data includes: -Institutionalized medical records and databases from hospital and pharmacy claims. -System wide databases from health insurance claims or pharmaceutical organization. -Field data like records from dispensers, sellers or distributers. -Experimental clinical trial data.
- 7. Types Epidemiological study can be divided into two types: 1. Observational study 2. Intervention study
- 8. Epidemiologic study design EPIDEMIOLOGIC STUDY OBSERVATIONAL INTERVENTION DESCRIPTIVE ANALYTICAL ECOLOGICAL CASE REPORT CASE SERIES CROSS SECTIONAL CROSS SECTIONAL CASE CONTROL COHORT HYBRID DESIGN CONCURRENT NON- CONCURRENT CLINICAL TRIALS FIELD TRIALS COMMUNITY INTERVENTION STUDIES
- 9. Observational studies • Observational studies in pharmacoepidemiology involves observing and measuring the effects of drugs on populations without intervening or manipulating the drug exposure. Interventional studies • Interventional studies involves an active attempt to change a disease determinant (eg: an exposure or behaviour) or the progress of a disease (through treatment).
- 10. Descriptive epidemiology •Descriptive study : focuses on the description of the occurrence of disease in a population. •Purpose of descriptive epidemiology: To generate hypothesis To permit evaluation of trends in health and disease and comparisons among countries and subgroups within countries. To provide a basis for planning and evaluation of health services
- 11. Case reports •It is the simplest form of observational studies. •During their daily routine, practitioners notice the emergence of an outcome and relate it to a drug exposure. •The reporting of that event through an official reporting system or medical or pharmacy journal generates a signal that alerts others to the possibility of casual association. •Eg: case report of a patient treated with minoxidil that was discovered to stimulate the hair growth.
- 12. Case series •A case series is a set of similar case reports identified either by exposure or by outcome. •It resembles an open trial of a drug, except that it lacks a formal protocol. •Enlarges the information about drug use and their consequences. •Help to confirm ADRs or indications of the drug •Eg: Adverse effects associated with the use of olanzapine in 5 children with severe behavioural problems. Adverse events includes: weight gain (3/5 children), sedation(2/3 children).
- 13. Ecological studies •It involves the plotting of data over time. •By inspecting the plot, patterns may emerge that can explain events that have occurred. •They are useful to provide rapid evidence for hypotheses. •Eg : If a new pharmacy law passes or a drug policy is implemented, we can plot drug usage over time and note what happens before and after the change.
- 14. Cross-sectional study •These studies are examinations of the use of drugs at one specific point in a time. •They are usually done through surveys, charts reviews and data base analyses. •Such information can be used for formulary management and policy development. •Used to compare drug use between countries or regions within in a country. •These studies can identify problems areas and suggest where remedial action should be directed.
- 15. Case-control study •These studies compares cases with disease to controls without disease. Design of a case- control study Not exposed Exposed Exposed Not exposed Cases (people with disease) Start with Controls (people without disease) Population Time
- 16. 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. Design of a cohort study Population People without the disease Exposed Not exposed Disease No disease Disease No disease Time
- 17. Clinical trials •Clinical trials are a type of intervention study. •Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. •Clinical trial produce the best data available for health care decision making. Types of clinical trials: 1. Randomized controlled trials (participants are randomly assigned to either an intervention group or control group ) 2. Non-randomized controlled trail (participants are assigned to groups, but not randomly)
- 18. Field trials •Field trials are a type of intervention study. •Researchers test a new treatment, programs, or strategy in real-life, involving large groups of people or communities. •These trials usually happen outside of hospitals or labs, such as in school villages, towns or workplaces. •These studies involves hundreds or thousands of people.
- 19. Applications of Pharmacoepidemiology 1. Drug Safety Surveillance (Pharmacovigilance) •Detects, assesses, and prevents adverse drug reactions (ADRs). •Identifies long-term or rare side effects post-marketing. •Supports risk-benefit analysis of medications. 2. Post-Marketing Surveillance •Monitors drugs after approval to evaluate real-world safety and effectiveness. •Detects adverse events not seen in clinical trials. 3. Drug Utilization Studies •Examines patterns, quality, and appropriateness of drug use. •Helps improve prescribing practices and optimize therapy.
- 20. 4. Comparative Effectiveness Research • Compares different treatments to determine which works best for whom. • Supports evidence-based healthcare decision-making. 5. Evaluation of Risk Factors • Assesses patient characteristics (e.g., age, genetics, comorbidities) that may affect drug response or side effects. 6. Support for Regulatory Decision Making •Provides data for new drug approvals, labeling, or withdrawal. •Informs regulatory agencies like FDA, EMA, CDSCO.
- 21. References 1. Strom, B. L., Kimmel, S. E., & Hennessy, S. (2019). Pharmacoepidemiology (6th ed.). Wiley- Blackwell. 2. McMahon, A. D. (2003). Approaches to pharmacoepidemiology. British Journal of Clinical Pharmacology. 3. World Health Organization (WHO). (2002). Safety of Medicines: A guide to detecting and reporting adverse drug reactions. WHO Publications. 4. A review of uses of health care utilization databases for epidemiologic research on therapeutics. Journal of Clinical Epidemiology. 5. Grimes, D. A., & Schulz, K. F. (2002). Descriptive studies: what they can and cannot do. The Lancet.
- 22. 6. Gagnon, M. A., & Lexchin, J. (2008). The cost of pushing pills: a new estimate of pharmaceutical promotion expenditures in the United States. 7. Morgenstern, H. (1995). Ecologic studies in epidemiology: concepts, principles, and methods. Annual Review of Public Health. 8. Mann, C. J. (2003). Observational research methods. Research design II: cohort, cross sectional, and case- control studies. 9. Pirmohamed, M. (2004). Adverse drug reactions as cause of admission to hospital: prospective analysis.
- 23. Thank You!