Assessment of Antibiotic Use and Concordance with Practice Guidelines within Three Diverse Ambulatory Clinic Systems

Abstract Objectives The objectives of this study were (1) to determine the rate of antibiotic prescribing at ambulatory clinics, and (2) to assess the concordance of antibiotic prescriptions with published guidelines and FDA-approved indications in terms of drug choices and dosing regimen. Methods In this cross-sectional study, patients of all ages receiving at least one prescription during ambulatory visits in 2016-17 were observed. For each of three clinic systems included in this study, oral antibiotic prescribing rates were estimated per patient and per ambulatory visit. Then, the concordance of oral antibiotic prescribing was assessed with respect to (1) choice of agent and (2) dosing regimen by comparing it to the recommended therapeutic regimen (RTR). Results A total of 284,348 patients receiving at least one prescription were included in the analysis. Between clinics, 17.4 to 43.7 per 100 patients received antibiotics. Of the antibiotics prescribed, 48.9% in Clinic A, 48.0% in Clinic B, and 60.7% in Clinic C were considered to be discordant in terms of drug choice. When the dosing regimen was taken into account in addition to the choice of agent, 72.6% in Clinic A, 76.7% in Clinic B, and 81.6% in Clinic C were discordant based on drug choice or dosing regimen. Of the prescriptions written with a discordant dosing regimen, 91.2% in Clinic A, 79.6% in Clinic B, and 91.0% in Clinic C were at a higher dosage than RTR. Conclusions Antibiotic prescribing rates vary by clinics, whereas discordant prescribing is consistently prevalent across clinics. More efforts should be put into ambulatory care to address antibiotic misuse problems, and our method could improve ambulatory antimicrobial stewardship programs.