Which Patients Discharged to Home-Based Outpatient Parenteral Antimicrobial Therapy Are at High Risk of Adverse Outcomes?

BACKGROUND: Patients increasingly receive home-based outpatient parenteral antimicrobial therapy (OPAT). Understanding which patients might be at higher risk of complications is critical in effectively triaging resources upon and after hospital discharge. METHODS: A prospective cohort of patients discharged from 1 of 2 academic medical centers in Baltimore, Maryland, between March 2015 and December 2018 were consented and randomly divided into derivation and validation cohorts for development of a risk score for adverse OPAT outcomes. Data from the derivation cohort with the primary outcome of a serious adverse outcome (infection relapse, serious adverse drug event, serious catheter complication, readmission, or death) were analyzed to derive the risk score equation using logistic regression, which was then validated in the validation cohort for performance of predicting a serious adverse outcome. RESULTS: Of 664 patients in the total cohort, half (332) experienced a serious adverse outcome. The model predicting having a serious adverse outcome included type of catheter, time on OPAT, using a catheter for chemotherapy, using a catheter for home parenteral nutrition, being treated for septic arthritis, being on vancomycin, being treated for Enterococcus, being treated for a fungal infection, and being treated empirically. A score ≥2 on the serious adverse outcome score had a 94.0% and 90.9% sensitivity for having a serious adverse outcome in the derivation and validation cohorts, respectively. CONCLUSIONS: A risk score can be implemented to detect who may be at high risk of serious adverse outcomes, but all patients on OPAT may require monitoring to prevent or detect adverse events.