An evaluation of risk factors for readmission in patients receiving outpatient parenteral antimicrobial therapy

BACKGROUND: Outpatient parenteral antimicrobial therapy (OPAT), when required, is beneficial to patients and healthcare systems by reducing hospital length-of-stay, providing cost savings, and improving patient satisfaction. OBJECTIVES: The purpose of this study is to determine readmission rates and associated risk factors in patients receiving OPAT at home. METHODS: This retrospective study included hospitalized patients 15 years and older who were discharged on intravenous antimicrobial therapy via OPAT at home between January 2018 and December 2019. Patients receiving antimicrobials at a skilled nursing facility, long-term acute care, or dialysis center, and those who began OPAT at home directly from the outpatient setting were excluded. The primary outcome of this study was all-cause 30-day readmission rate. Secondary outcomes included 90-day readmission rate, rates of complications related to OPAT, emergency department visits during OPAT, and predictors of all-cause 30-day readmission through a logistic regression analysis. RESULTS: Two hundred individual patients were included in the analysis; 60% were male and the mean age was 49 years. The most common indications for OPAT at home were bone and joint infection (52%) and bacteremia (26%). Forty patients (20%) experienced an unplanned, all-cause 30-day readmission, with a total of 48 readmission events. Of the 40 patients who were readmitted within 30 days, 20 (50%) were due to non-OPAT related reasons. Sixty patients (30%) experienced an OPAT-related complication, and chronic kidney disease was found to be an independent predictor of readmission (OR: 2.8, 95% CI: 1.0–7.6). CONCLUSIONS: Patients receiving OPAT at home are at increased risk for early hospital readmission, but it is often due to reasons not associated with OPAT. Patients with chronic kidney disease beginning OPAT at home should be closely monitored after discharge.