1837. Evaluation of Disparities in Beta-Lactam Allergies and Subsequent Antibiotic Use in Outpatients with Acute Bacterial Skin and Skin Structure Infections

Abstract

Abstract Background Black patients with skin and soft tissue infections are more likely to have a documented penicillin allergy and use of non-beta-lactams than white patients. We sought to compare the prevalence and risk factors for documented beta-lactam allergy (D-BLA) among racial and ethnic minorities (REM) and white patients and beta-lactam (BL) use for outpatient Acute Bacterial Skin and Skin Structure Infections (ABSSSIs). Methods We conducted a cohort study of adult outpatients (18-90 years) seen by the Texas Tech University Health Science Center Physicians group (2012-2021). All patients had an ICD-9 or ICD-10 code for an ABSSSI in the primary or secondary position. Descriptive statistics were reported. Logistic regression models were used to determine which factors were statistically associated with D-BLA and which factors were associated with BL use for the ABSSSI. Multivariable (MV) analysis results were reported as odds ratios (OR) and 95% confidence intervals (95%CI). All analyses were conducted in R. Results REM represented 38% of the 21,673 patients in the cohort. A D-BLA was present for 18% percent of all patients and was higher in white patients than REM (22 vs 13%). Factors associated with D-BLA on MV analysis of the total cohort were age (OR 1.01 per year, 95%CI 1.01-1.01), Medicaid (OR 1.18, 95%CI 1.04-1.34), or Medicare (OR 1.17, 95%CI 1.05-1.31). Factors associated with a lower likelihood of D-BLA on MV analysis of the entire cohort were REM (OR 0.55, 95%CI 0.51-0.60) and male sex (OR 0.56, 95%CI 0.52-0.60). Regarding BL use, white patients were less likely to receive a BL than REM (26 vs 30%). Factors associated with a reduced likelihood of BL use on MV analysis of the total cohort were D-BLA (OR 0.60, 95%CI, 0.54-0.67), Medicaid (OR 0.83, 95%CI 0.74-0.93), or Medicare (OR 0.64, 95%CI 0.58-0.70). Factors associated with BL use on MV analysis of the entire cohort were REM (OR 1.20, 95%CI 1.12-1.28), male sex (OR 1.45, 95%CI 1.36-1.54), or self-pay (OR 1.52, 95%CI 1.37-1.68). The interaction term between REM and D-BLA was not significant for BL use. Conclusion REM were at a reduced risk of a D-BLA in our cohort and were more likely to receive a BL for ABSSSIs. Payor status and sex also significantly impacted rates of D-BLA and BL use. Disclosures Ronald G. Hall, II, PharmD, MSCS, Merck: Grant/Research Support Carlos Alvarez, PharmD, MSc, MSCS, Boehringer Ingelheim: Grant/Research Support|Bristol Myer Squibb: Grant/Research Support|Merck: Grant/Research Support