Clinical efficacy and cost-effectiveness of outpatient parenteral antibiotic therapy (OPAT): a UK perspective

Outpatient parenteral antibiotic therapy (OPAT) is an effective treatment strategy for a wide variety of infections as long as clinical risk is minimized by conforming to practice guidelines. However, its cost-effectiveness has not been established in the setting of the UK National Health Service. We examined the clinical efficacy and cost-effectiveness of an OPAT service based in a large UK teaching hospital, predominantly using the outpatient 'infusion centre' and patient/carer administration models of service delivery. Data on clinical activity and outcomes were collected prospectively on 334 episodes of treatment administered by the Sheffield OPAT service between January 2006 and January 2008. Cost-effectiveness was calculated by comparing real costs of OPAT with estimated inpatient costs for these patient episodes incorporating two additional sensitivity analyses. Of the OPAT episodes, 87% resulted in cure or improvement on completion of intravenous therapy. The readmission rate was 6.3%, and patient satisfaction was high. OPAT cost 41% of equivalent inpatient costs for an Infectious Diseases Unit, 47% of equivalent inpatient costs using national average costs and 61% of inpatient costs using minimum inpatient costs for each diagnosis. Using this service model, OPAT is safe and clinically effective, with low rates of complications/readmissions and high levels of patient satisfaction. OPAT is cost-effective when compared with equivalent inpatient care in the UK healthcare setting.