Comparison of Outcomes in Outpatient Parenteral Antimicrobial Therapy (OPAT) Patients Receiving Vancomycin vs. Non-Vancomycin Anti-MRSA Therapy

Abstract

BackgroundThis evaluation set out to determine whether vancomycin therapy was associated with higher rates of clinical failure compared with non-vancomycin anti-methicillin-resistant Staphylococcus aureus therapy (NVAMT) in outpatient parenteral antimicrobial therapy (OPAT).MethodsThis was a retrospective, single center cohort study including patients who received ≥7 days of OPAT with vancomycin, ceftaroline, or daptomycin from January 1, 2009 through March 31, 2016 at the VA Saint Louis Healthcare System. The primary outcome was clinical failure, defined as a composite of acute kidney injury (AKI), creatinine phosphokinase elevations ≥ 500 units/L, adverse drug events necessitating a change in therapy, readmission due to recurrence of infection, or reinitiation of antibiotics after discontinuation. Secondary outcomes were the individual components of the composite primary outcome. Multivariate logistic regression was used to evaluate independent risk factors for clinical failure. Factors evaluated for inclusion in the multivariate model were age >65 at initiation, creatinine clearance >50 mL/minute, length of therapy >28 days, concomitant antibiotic therapy, comorbid disease states, and vancomycin therapy.ResultsA total of 125 patients were included in the analysis – 72 receiving vancomycin and 53 receiving NVAMT. Baseline characteristics between groups were similar, except patients in the NVAMT group had a greater mean serum creatinine and a higher rate of CKD at baseline; 1.53 vs 1.23 (P = 0.032) and 35.9% vs. 19.4% (P = 0.04) respectively. Forty-three percent (31/72) of patients receiving vancomycin achieved clinical failure compared with 54.7% (29/53) of NVAMT patients (P = 0.197). Of the secondary outcomes analyzed, only readmission due to recurrence was significant between groups (vancomycin vs. NVAMT) – 13.8% vs. 30.2% (P = 0.026). In the univariate model only the choice of vancomycin met pre-defined criteria (P < 0.2) for inclusion in the multivariate model. In the multivariate analysis the choice of vancomycin was not found to be significant (0.71 (95% CI 0.33–1.52), P = 0.37).ConclusionVancomycin was not associated with an increased risk of clinical failure when compared with NVAMT in patients receiving OPAT.Disclosures All authors: No reported disclosures.