Prevalence and risk factors associated with readmission with acute kidney injury in patients receiving vancomycin outpatient parenteral antimicrobial therapy

Introduction: Vancomycin is commonly used during outpatient parenteral antimicrobial therapy (OPAT). Therapeutic drug monitoring (TDM) of vancomycin is recommended to ensure effective and safe therapy, as use has been associated with acute kidney injury (AKI). Methods: The MarketScan® Commercial Database was queried from 2010 to 2016 to identify patients aged 18–64 years discharged from an inpatient hospitalization on vancomycin OPAT. The primary endpoint was hospital readmission with AKI within 6 weeks of index hospital discharge. TDM was defined as at least one vancomycin level obtained during outpatient therapy. Bivariate analysis was used to examine associations with outcomes; significant factors were incorporated into a multivariable logistic regression model. Results: A total of 14,196 patients were included in the study; median age was 54 years and 53.8% were male. Readmission with AKI occurred in 385 (2.7%) and was independently associated with chronic kidney disease (aOR 2.63 [95%CI 1.96–3.52]), congestive heart failure (1.81 [1.34–2.44]), chronic liver disease (1.74 [1.17–2.59]), hypertension (1.73 [1.39–2.17]), septicemia (1.61 [1.30–2.00]), and concomitant OPAT with IV penicillins (1.73 [1.21–2.49]) while skin and soft tissue infection (0.67 [0.54–0.83]) and surgical site infection (0.74 [0.59–0.93]) were associated with lower risk of readmission with AKI. TDM was not associated with lower risk of readmission with AKI. Conclusion: Chronic kidney disease, congestive heart failure, hypertension, chronic liver disease, septicemia, and concomitant OPAT with IV penicillins were significantly associated with higher risk of readmission with AKI during vancomycin OPAT.