Chronic Anticoagulation is Associated With Significantly Increased Rates of Medical Complications, Periprosthetic Joint Infection, and Revision After Primary Total Knee Arthroplasty.

Background: The proportion of patients undergoing total knee arthroplasty (TKA) who are on chronic anticoagulation (CA) is increasing. As existing literature is limited, the purpose of this study was to compare complication rates after primary TKA among patients who were vs were not on CA. Methods: This is a retrospective cohort study using the IBM MarketScan databases. Patients who underwent primary TKA were dichotomized into the CA or control cohort based upon the presence or absence, respectively, of claims for direct oral anticoagulants, warfarin, or low-molecular-weight heparin within 6 months both before and after TKA. Rates of readmissions, medical complications within 90 days, periprosthetic joint infection (PJI), and all-cause revision at 2 years were compared with multivariable logistic regression. Results: A total of 181,760 patients met inclusion criteria, including 13,967 (7.7%) on CA. At 90 days, the CA cohort exhibited significantly higher rates of sepsis (0.9 vs 2.2%; odds ratio (OR) 1.7; Conclusions: CA was associated with significantly higher rates of readmission, medical complications, PJI, and all-cause revision after primary TKA. This data highlights the importance of preoperative medical optimization and perioperative medical management in this population.