996. Impact of Penicillin Allergy Labels on Carbapenem Use in a Multi-Center Study

BACKGROUND: Antibiotic allergy labels lead to excess exposure to broad-spectrum antibiotics and can result in patient harm. We aimed to describe the prevalence of penicillin allergy labels (PAL) across a variety of hospital settings and its association with carbapenem exposure. METHODS: We performed a retrospective cohort analysis of inpatient admissions from 14 hospitals in the Duke Antimicrobial Stewardship Outreach Network (DASON) and Duke Health System from 2016 to 2018. Data were collected from the DASON central database which is derived from electronic health record extracts. PAL was defined from drug allergy documentation indicating any reaction to penicillin or its related agents, but did not include labels for other β-lactam agents (e.g., cephalosporin). Carbapenem exposure was defined as a binary variable indicating receipt of at least one dose of meropenem, ertapenem, doripenem or imipenem on an inpatient unit. The association between PAL and carbapenem exposure was assessed using multivariable logistical regression with candidate covariates including age, gender, comorbidity score, and exposure to intensive care or hematology/oncology unit. Hospital-level PAL prevalence was defined as the percentage of inpatient admissions. Hospital-level carbapenem use rates were assessed as days of therapy (DOT) per 1000 patient-days and stratified by PAL to understand the portion of use associated with PAL. RESULTS: Of the 727,168 admissions included in this study, 84,033 (11.6%) patients had a PAL. The majority of admissions with documented PAL were in patients >65 years old (47.9%, n = 40,240) and female (57.8%, n = 418,472). PAL was associated with a 2-fold higher risk of receipt of carbapenem (adjusted odds ratio 2.13, 95% CI 0.89–2.40, P < 0.0001). PAL prevalence varied among hospitals (median 14%, range 5–20%). Hospitals with antibiotic allergy-focused stewardship programs (ASP) had a similar PAL prevalence (median 13.8 vs. 15.9%, P = 0.08), but the percent of carbapenem DOT used in patients with PAL was similar (median 23% vs. 24%, P = 0.6). CONCLUSION: PAL was associated with increased carbapenem exposure on the patient level. Allergy-focused ASP activities may affect PAL but it is unclear whether it reduces carbapenem use based on these observational data. DISCLOSURES: All authors: No reported disclosures.