Prevalence of Inappropriate Antibiotic Prescribing in Primary Care Clinics within a Veterans Affairs Health Care System

Abstract

Data are needed from outpatient settings to better inform antimicrobial stewardship. In this study, a random sample of outpatient antibiotic prescriptions by primary care providers (PCPs) at our health care system was reviewed and compared to consensus guidelines. Over 12 months, 3,880 acute antibiotic prescriptions were written by 76 PCPs caring for 40,734 patients (median panel, 600 patients; range, 33 to 1,547). PCPs ordered a median of 84 antibiotic prescriptions per 1,000 patients per year. Azithromycin (25.8%), amoxicillin-clavulanate (13.3%), doxycycline (12.4%), amoxicillin (11%), fluoroquinolones (11%), and trimethoprim-sulfamethoxazole (10.6%) were prescribed most commonly. Medical records corresponding to 300 prescriptions from 59 PCPs were analyzed in depth. The most common indications for these prescriptions were acute respiratory tract infection (28.3%), urinary tract infection (23%), skin and soft tissue infection (15.7%), and chronic obstructive pulmonary disease (COPD) exacerbation (6.3%). In 5.7% of cases, no reason for the prescription was listed. No antibiotic was indicated in 49.7% of cases. In 12.3% of cases, an antibiotic was indicated, but the prescribed agent was guideline discordant. In another 14% of cases, a guideline-concordant antibiotic was given for a guideline-discordant duration. Therefore, 76% of reviewed prescriptions were inappropriate. Ciprofloxacin and azithromycin were most likely to be prescribed inappropriately. A non-face-to-face encounter prompted 34% of prescriptions. The condition for which an antibiotic was prescribed was not listed in primary or secondary diagnosis codes in 54.5% of clinic visits. In conclusion, there is an enormous opportunity to reduce inappropriate outpatient antibiotic prescriptions.

Keywords: antimicrobial stewardship; inappropriate prescribing; outpatient; prescribing patterns; primary care.

FIG 1

Distribution of antibiotic indices for providers with panel sizes >100 patients. Considerable variation was observed. The median antibiotic index was 84 (dashed line).

FIG 2

Appropriateness of antibiotic prescribing for the most common outpatient indications. The data highlight that there are vast opportunities for interventions to improve practice and that optimal interventions are likely to differ by indication.