JNTU Pharm. D V Year PHARMACOEPIDEMIOLOGY AND PHARMACOECONOMICS Previous Question Paper (April - 2023 - R08)

Drug use measures are quantitative tools used in pharmacoepidemiology to assess the patterns, extent, and quality of drug utilization within a population. These measures provide the data necessary to evaluate therapeutic practices and identify potential safety or efficacy issues.

Key drug use measures include:

• Defined Daily Dose (DDD): The assumed average maintenance dose per day for a drug used for its main indication in adults. It serves as a technical unit of measurement to compare drug consumption across different settings and time periods.
• Prescribed Daily Dose (PDD): The actual average dose prescribed by clinicians, which may differ from the DDD. Comparing PDD to DDD helps identify over- or under-utilization.
• Drug Utilization 90% (DU90%): A method identifying the drugs that account for 90% of the total volume of drug use. It is used to focus quality improvement efforts on the most frequently used medications.
• Therapeutic Intensity Index: A measure of the number of drugs or the complexity of regimens prescribed to a single patient, often used in hospital settings.

Prevalence studies in pharmacoepidemiology are cross-sectional assessments that determine the proportion of a population using a specific drug or experiencing a drug-related event at a single point in time or over a defined short interval.

Objectives:

• To estimate the burden of drug use within a specific population.
• To identify demographic or clinical characteristics associated with drug exposure.
• To monitor trends in prescribing patterns and identify potential polypharmacy.
• To provide baseline data for planning public health interventions.

Methodology:

1. Define the study population: Clearly specify the inclusion and exclusion criteria, such as age, disease state, or healthcare setting (e.g., hospital vs. community).
2. Data Collection: Utilize sources such as electronic health records, pharmacy dispensing databases, or patient surveys to capture drug exposure data at the index date.
3. Classification: Categorize medications using standardized systems like the Anatomical Therapeutic Chemical (ATC) classification.
4. Calculation: Calculate the prevalence proportion using the formula:
   Prevalence = (Number of individuals using the drug at time t / Total population at risk at time t) × 100
5. Analysis: Perform statistical analysis to determine associations between drug use and variables such as age, gender, or comorbidities, ensuring adjustment for potential confounding factors.