title: Rivaroxaban vs. low molecular weight heparin for the prevention of venous thromboembolism after hip or knee arthroplasty: a cohort study.
abstract: BACKGROUND
  Rivaroxaban is increasingly used to prevent venous thromboembolism after hip or knee arthroplasty. Studies evaluating the effectiveness of rivaroxaban compared to low molecular weight heparin after orthopedic surgery in routine practice are scarce.
  
  
  METHODS
  We conducted a retrospective cohort study in 121 hospitals in Ontario, Canada, between 2002 and 2012. We included patients aged 66 years or older (median age 73 years) who received an outpatient prescription for subcutaneous low molecular weight heparin (n = 11 471) or oral rivaroxaban (n = 12 850) on hospital discharge after a total knee or hip arthroplasty. The two coprimary outcomes assessed within 30 days of the prescription date were emergency department visit or hospitalization with venous thromboembolism (either deep vein thrombosis or pulmonary embolism; primary efficacy outcome) and a hospitalization with non-traumatic major hemorrhage (primary safety outcome).
  
  
  RESULTS
  Rivaroxaban use increased over the study period. Compared to low molecular weight heparin, rivaroxaban was associated with a lower 30-day risk of hospitalization with venous thromboembolism (0.47% vs. 0.81%; relative risk 0.58; 95% confidence interval 0.42-0.81; P = 0.001) with no significant difference in hospitalizations for major bleeding (0.18% vs. 0.20%; relative risk 0.89; 95% confidence interval 0.50-1.59; P = 0.700).
  
  
  CONCLUSIONS
  In routine practice, anticoagulant prophylaxis with rivaroxaban compared to low molecular weight heparin after hospital discharge from total hip or knee arthroplasty is associated with a lower risk of symptomatic venous thromboembolism with no difference in the risk of bleeding.
authors: Division of Hematology, Department of Medicine, University of Western Ontario, London, ON, Canada; Department of Epidemiology and Biostatistics, University of Western Ontario, London, ON, Canada; Institute for Clinical Evaluative Sciences - Western (ICES Western), London, ON, Canada.
authors: A
authors: A
authors: Lazo-Langner
authors: J L
authors: JL
authors: Fleet
authors: E
authors: E
authors: McArthur
authors: A X
authors: AX
authors: Garg
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage; D001178:Arthroplasty / Q000009:adverse effects; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D065427:Factor Xa Inhibitors / Q000008:administration & dosage; D005260:Female; D006470:Hemorrhage; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage*; D006615:Hip / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008970:Molecular Weight; D009025:Morpholines / Q000008:administration & dosage*; D009864:Ontario; D012189:Retrospective Studies; D000069552:Rivaroxaban; D013876:Thiophenes / Q000008:administration & dosage*; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000517:prevention & control*
chemical_list: D000925:Anticoagulants; D065427:Factor Xa Inhibitors; D006495:Heparin, Low-Molecular-Weight; D009025:Morpholines; D013876:Thiophenes; D000069552:Rivaroxaban
keywords: arthroplasty; low molecular weight heparin; prophylaxis; rivaroxaban; venous thromboembolism