Cost analysis of an adult outpatient parenteral antibiotic therapy (OPAT) programme - A Canadian teaching hospital and ministry of health perspective

Background: Outpatient parenteral antibiotic therapy (OPAT) programmes have become prevalent over the past 2 decades. From the US perspective, these p rogrammes have been shown to reduce healthcare costs. No comprehensive anal ysis has been published from the Canadian perspective. Objective: To describe a Canadian OPAT programme for the 3-year period sinc e its inception and to conduct a treatment cost analysis. Design and methods: Demographics and resource utilisation data (health prof essional labour, laboratory acid diagnostic tests, antimicrobials, delivery , home nursing care, catheters and catheter placement) were prospectively c ollected for enrollees in the OPAT programme over the evaluation period. Av oided hospital resource utilisation was estimated via retrospective chart r eview by the investigators. Costs were retrospectively assigned to each res ource and total cost avoidance by the OPAT programme was determined from ea ch perspective. Perspective: A teaching hospital and a provincial Ministry of Health (MOH). Main outcome measures and results: 140 treatment courses were initiated for 117 adult patients (mean age 54 years) who were enrolled into the programm e. Mean pre-OPAT length of hospital stay was 12 days, and mean OPAT duratio n was 22.5 days. Bone/joint (39%), skin and soft tissue (16%), cardiac (13% ) and respiratory tract (12%) infections were the most common infections ma naged. The most commonly used antimicrobials were vancomycin (29%), cloxaci llin +/- gentamicin (22%) and ceftriaxone +/- gentamicin (11%). 85% of enro llees successfully completed their planned antimicrobial treatment regimens . Premature discontinuation of antimicrobial therapy for various reasons oc curred in the remaining 15% of courses. The mean cost per treatment course of OPAT was 1910 Canadian dollars ($Can) from the hospital perspective and $Can6326 from the MOH perspective. Assuming that patients would have otherw ise completed their antimicrobial therapy in hospital, the mean cost per tr eatment course was estimated to be $Can 14 271. The overall cost avoidance of the OPAT programme was $Can 1 730 530 (hospital perspective) and $Can1 0 09 450 (MOH perspective) over the 3-year assessment period. Sensitivity ana lyses revealed the results to bt: robust to plausible changes. Conclusions: This analysis supports the premise that an adult OPAT programm e can substantially reduce healthcare costs in the Canadian healthcare sett ing.