Economic burden of skin and skin structure infections due to Gram-positive bacteria in patients on hospital at home-based outpatient parenteral antibiotic therapy (OPAT)

Objective. To describe and quantify resource use and direct health costs associated with skin and skin structure infections (SSSIs) caused by Gram-positive bacteria in adults receiving outpatient parenteral antimicrobial therapy (OPAT), administered by Hospital at Home units (HaH) in Spain. Material and methods. Observational, multicenter, retrospective study. We included patients of both sexes included in the HaH-based OPAT Registry during 2011 to 2017 who were hospitalized due to SSSIs caused by Gram-positive bacteria. Resource use included home visits (nurses and physician), emergency room visits, conventional hospitalization stay, HaH stay and antibiotic treatment. Costs were quantified by multiplying the natural units of the resources by the corresponding unit cost. All costs were updated to 2019 euros. Results. We included 194 episodes in 189 patients from 24 Spanish hospitals. The most frequent main diagnoses were cellulitis (26.8%) and surgical wound infection (24.2%), and 94% of episodes resulted in clinical improvement or cure after treatment. The median HaH stay was 13 days (interquartile range [IR]:8-22.7), and the conventional hospitalization stay was 5 days (IR: 1-10.7). The mean total cost attributable to the complete infectious process was _7,326 (95% confidence interval: _6,316-_8,416). Conclusions. Our results suggest that OPAT administered by HaH is a safe and efficient alternative for the management of these infections and could lead to lower costs compared with hospital admission.