Economic evaluation of outpatient parenteral antimicrobial therapy: a systematic review

Introduction: Outpatient parenteral antimicrobial therapy (OPAT) consists of providing antimicrobial therapy by parenteral infusion without hospitalization. A systematic review was performed to compare OPAT and hospitalization as health care modalities from an economic perspective.Areas covered: We identified 1455 articles using 13 electronic databases and manual searches. Two independent reviewers identified 35 studies conducted between 1978 and 2016. We observed high heterogeneity in the following: countries, infection site, OPAT strategies and outcomes analyzed. Of these, 88% had a retrospective observational design and one was a randomized trial. With respect to economic analyses, 71% of the studies considered the cost-consequences, 11% cost minimization, 6% cost-benefit, 6% cost-utility analyses and 6% cost effectiveness. Considering all 35 studies, the general OPAT cost saving was 57.19% (from -13.03% to 95.47%). Taking into consideration only high-quality studies (6 comparative studies), the cost saving declined by 16.54% (from -13.03% to 46.86%).Expert commentary: Although most studies demonstrate that OPAT is cost-effective, the magnitude of this effect is compromised by poor methodological quality and heterogeneity. Economic assessments of the issue are needed using more rigorous methodologies that include a broad range of perspectives to identify the real magnitude of economic savings in different settings and OPAT modalities.