243 - Temporal Trends in Appropriateness of Ambulatory Antibiotic Prescribing in South Carolina

Background: Previous studies have reported high levels of inappropriate ambulatory antibiotic prescribing in the United States. This population-based cohort study examines temporal trends in appropriateness of ambulatory antibiotic prescribing in South Carolina.

Methods: Aggregated pharmacy claims data for oral antibiotic prescriptions among South Carolina residents < 65 years old were matched with primary diagnosis codes from medical claims within 14 days of the pharmacy claim from 2012-2017. Appropriateness of antibiotics was defined as maybe indicated or not indicated based on diagnosis codes. Chi-square tests were used to examine overall temporal trend in appropriateness and the trends across age group and gender.

Results: During the 6-year period, 3,133,379 prescriptions were identified. Overall, 25.6% of antibiotic prescriptions filled were not indicated. This decreased from 27.9% in 2012 to 22.7% in 2017 (p < 0.001). The most common not indicated conditions were viral upper respiratory infections (39.1%), bronchitis (26.7%), and serous otitis (10.9%). The most common maybe indicated conditions were bacterial otitis (27.5%), acute bacterial tonsillitis (24.8%), and sinusitis (23.6%). While females filled more antibiotic prescriptions, they were less likely than males to have a not indicated condition (24.7% vs. 27.1%, p < 0.001). Prescribing for not indicated conditions was more likely in adults aged 40-64 (33.7%) than those aged 18-39 (23.5%) and < 18 (24.2%).

Conclusion: The observed decline in inappropriate ambulatory antibiotic prescribing from 2012 to 2017 in South Carolina represents welcomed news. Further improvements in ambulatory antibiotic stewardship efforts are needed particularly in men ≥ 40 years old with acute respiratory infections.