Two-Year Burden of Antibiotic Use for Prosthetic Joint Infection Following Total Knee Arthroplasty

Introduction: Prosthetic joint infection (PJI) after total knee arthroplasty (TKA) poses an economic burden on patients and the healthcare system. Our study aims to estimate the total days and cost of therapeutic antibiotic use among patients with PJI after TKA. Patients and Methods: A nationwide claims database study was conducted. Primary exposure was the diagnosis of PJI within 90 days post-TKA. Outcomes were days of antibiotic use and costs associated with antibiotics over the 2-year period post-TKA. Propensity score matching analysis was performed to adjust for patient and provider characteristics. Results: A total of 13,201 patients (female 59.0%, age 59.4 ± 8.4, PJI 1.0%) were included in the study. Patients with PJI had 135.8 more days of antibiotic use than patients without PJI (p < 0.001). PJI patients spent $2138.9 more on antibiotics than those without PJI (p < 0.001). The attributable cost of antibiotics use for PJI patients is estimated to be $12 million over two years following acute PJI diagnosis and reflects 814,000 antibiotic-days of therapy. Discussion and Conclusion: Patients with early PJI receive a large quantity of antibiotics and contribute to overall antibiotic use and cost. Reducing early PJI after TKA would be expected to have considerable antimicrobial stewardship benefits.