Trends in Periprosthetic Hip Infection and Associated Costs: A Population-Based Study Assessing the Impact of Hospital Factors Using National Data

Background: Periprosthetic joint infection (PJI) is an important cost driver in hip arthroplasty revisions, thus necessitating careful trend monitoring. Recent national trend data are lacking; we therefore assessed national PJI burden, trends in prevalence, and hospitalization costs. Methods: We extracted data on hip arthroplasty revisions from the National Inpatient Sample (2003-2013; n = 465,209). Trends in PJI prevalence and hospitalization costs were (1) assessed for the full cohort and (2) stratified by hospital teaching status, hospital bed size (≤299, 300-499, and ≥500 beds), and hospital region (Northeast, Midwest, South, and West). The Cochran-Armitage trend test (PJI prevalence) and linear regression (hospitalization costs) determined significance of trends. Trends were adjusted for patient's age, gender, insurance type, race, Deyo-Charlson comorbidities, obesity, length of stay, and hospital characteristics. Results: Overall, PJI prevalence was 15.0% (n = 70,011); adjusted prevalence increased from 13.1% in 2003 to 16.4% in 2013 (P <.0001), while adjusted median PJI hospitalization costs increased from $28,240 in 2003 to $31,529 in 2013 (P <.0001). Rural hospitals had the lowest PJI burden (12.5%; n = 4,525), while urban and teaching hospitals had the highest PJI burden (16.4%; n = 40,297). The stratified analyses, particularly in large hospitals (>500 beds), showed that PJI prevalence increased from 13.0% (2003) to 17.4% (2013; a 33.8% increase; P <.0001). Similarly, PJI revision hospitalization costs increased from a median of $27,490 (2003) to $31,312 (2013; a 14% increase; P <.0001). Conclusion: The burden of PJI in hip arthroplasty revision is increasing and—while additional research is needed—there appears to be a particular shift of revision burden to larger hospitals with increasing costs.