Abstract
Revision total knee arthroplasty (TKA) procedures performed secondary to periprosthetic joint infection (PJI) are associated with significant morbidity and mortality. These poor outcomes may be further complicated by the development of postoperative infection requiring aggressive antibiotic treatment. However, this antibiotic overuse may suppress patients' native bacterial flora, leading to Clostridium difficile infection (CDI). With the increased demand for primary TKAs and expected rise in revision TKA due to PJI, it is important to identify factors contributing to CDI. Therefore, we aimed to study the: 1) incidence, 2) demographics, length of stay (LOS), and total costs, and 3) risk factors and mortality associated with CDI in revision TKA patients.
The National Inpatient Sample database was queried for all individuals diagnosed with PJI and who underwent revision TKA between 2009 and 2013. Patients who developed CDI during their in-patient hospital stay were identified, yielding 83,806 patients (799 with CDI) with a mean age of 65 (S.D.=11.2). Logistic regression analysis was conducted to assess the association between hospital- and patient-specific characteristics and the development of CDI.
During the study period, the overall incidence of CDI after revision TKA was 1%. These patients were significantly older (mean age 69.05 vs. 65.52 yrs), had greater LOS (median 11 vs. 5 days), had greater costs ($30,612.93 vs. 18,873.75), and had higher in-hospital mortality (3.6 vs. 0.5%, p < 0 .001 for all) compared to those without infection. Patients with CDI were more likely to be treated in urban, not-for-profit, medium or large bed-sized hospitals located in the Northeast or Midwest (p < 0 .05 for all). Patients with underlying depression (OR 4.267, p=0.007) or fluid/electrolyte disorders (OR 3.48, p=0.001) were more likely to develop infection.
Although CDI is a rare event following revision TKA, it can have detrimental consequences. Our report demonstrates that CDI is associated with longer LOS, higher costs, and greater in-hospital mortality. With increased legislative pressure to lower healthcare expenditures, it is crucial to identify means of preventing costly complications.
