BACKGROUND: Antimicrobial stewardship programs use a coordinated approach to promote appropriate antimicrobial use, a core strategy to reduce the development and spread of antimicrobial-resistant organisms. Kentucky has the highest outpatient antibiotic prescribing rate in the United States. The objective of our analysis was to better understand outpatient prescription patterns in Kentucky to help inform the development of an outpatient antimicrobial stewardship program.
METHODS: We used IMS Government Solutions antimicrobial data to conduct a descriptive analysis of 10.4 million outpatient prescriptions for antimicrobials written by Kentucky-based providers, including all professionals with the authority to prescribe to humans, in 2013–2014. We calculated the frequency of antimicrobial-specific prescriptions; assessed provider characteristics such as professional specialty (defined by the American Medical Association categorization scheme); and, using U.S. Census data, calculated prescription rates by patient gender.
RESULTS: The overall prescription rate was 1182.4 antimicrobial prescriptions per 1000 person-years (py). The most common antimicrobial prescribed was amoxicillin (n=2,071,233, 19.8% of prescriptions) followed by azithromycin (n=1,781,694, 17.1%). The most common categories of antimicrobials prescribed were aminopenicillins (n=2,091,173, 20.0%), extended spectrum macrolides (n=1,880,807, 18.0%), and cephalosporins (n=1,583,235, 15.2%). Among professional specialties, family medicine providers prescribed the highest absolute number of antimicrobials (n=2,314,069, 22.2%). The number of prescriptions per provider was highest among dermatologists, family medicine providers, and urologists. Outpatient prescription rates were higher among male patients (1,397 per 1000py) than female patients (970 per 1000py).
CONCLUSIONS: An outpatient antimicrobial stewardship program in Kentucky may need to target specific professional specialties and provide education on prescribing in the context of known antimicrobial resistance patterns. Additional data sources should be identified to help interpret variation in prescribing rates by professional specialty. Variations in prescribing rates by patient’s sex may reflect both true differences in the health of the population and differences in health-seeking behaviors; this should be further explored to determine if this should be considered when designing a stewardship program.