Factors influencing the cost of prosthetic joint infection treatment

Prosthetic joint infection (PJI) is associated with significant costs to the healthcare system. Current literature examines the cost of specific treatment modalities without assessing other cost drivers for PJI. Aims: To examine the overall cost of the treatment of PJI and to identify factors associated with management costs. Methods: The costs of treatment of prosthetic joint infections were examined in 139 patients across 10 hospitals over a 3-year period (January 2006 to December 2008). Cost calculations included hospitalization costs, surgical costs, hospital-in-the-home costs and antibiotic therapy costs. Negative binomial regression analysis was performed to model factors associated with total cost. Findings: The median cost of treating prosthetic joint infection per patient was Australian 34,800 (interquartile range: 20,305, 56,929). The following factors were associated with increased treatment costs: septic revision arthroplasty (67 increase in treatment cost; P=0.02), hypotension at presentation (70 increase; P=0.03), polymicrobial infections (41 increase; P=0.009), surgical treatment with one-stage exchange (100 increase; P=0.002) or resection arthroplasty (48 increase; P=0.001) were independently associated with increased treatment costs. Culture-negative prosthetic joint infections were associated with decreased costs (29 decrease in treatment cost; P=0.047). Treatment failure was associated with 156 increase in treatment costs. Conclusions: This study identifies clinically important factors influencing treatment costs that may be of relevance to policy-makers, particularly in the setting of hospital reimbursement and guiding future research into cost-effective preventive strategies.