BACKGROUND: In 2011, the American Academy of Orthopaedic Surgeons released a consensus recommending venous thromboembolism (VTE) prophylaxis after total knee arthroplasty (TKA). The purpose of our study was to examine (1) incidences of postoperative complications, including pulmonary embolism (PE), deep vein thrombosis (DVT), and transfusion rates; (2) trends from 2016 to 2021 in VTE prophylaxis; and (3) independent risk factors for 90-day total complications following TKA between aspirin, enoxaparin, rivaroxaban, and warfarin.
METHODS: Using a national, all-payer database from 2016 to 2021, we identified all patients who underwent primary TKA. Exclusions included all patients who had prescribed anticoagulants within 1 year prior to TKA, hypercoagulable states, and cancer. Data were collected on baseline demographics, including age, sex, diabetes, and a comorbidity index, in each of the VTE prophylaxis cohorts. Postoperative outcomes included rates of PE, DVT, and transfusion. Multivariable regressions were performed to determine independent risk factors for total complications at 90 days following TKA.
RESULTS: From 2016 to 2021, aspirin was the most used anticoagulant (n = 62,054), followed by rivaroxaban (n = 26,426), enoxaparin (n = 20,980), and warfarin (n = 13,305). The cohort using warfarin had the highest incidences of PE (1.8%) and DVT (5.7%), while the cohort using aspirin had the lowest incidences of PE (0.6%) and DVT (1.6%). The rates of aspirin use increased the most from 2016 to 2021 (32.1% to 70.8%), while the rates of warfarin decreased the most (19.3% to 3.0%). Enoxaparin, rivaroxaban, and warfarin were independent risk factors for total complications at 90 days.
CONCLUSIONS: An epidemiological analysis of VTE prophylaxis use from 2016 to 2021 shows an increase in aspirin following TKA compared to other anticoagulant cohorts in a nationally representative population. This approach provides more insight and a better understanding of anticoagulation trends over this time period in a nationally representative sample.
