6/28/23, 12:23 AM CRISTAL Pathway Feedback Search Clinical Topics Home Studies CRISTAL CRISTAL Disease Disease Hip osteoarthritis Knee osteoarthritis Trial question Is aspirin monotherapy noninferior to enoxaparin in patients undergoing hip or knee arthroplasty for OA? Study design Multi-center Open label RCT Population Characteristics of study participants 56.6% female N = 9203 43.4% male 9203 patients (5511 female, 4200 male) Inclusion criteria: adult patients undergoing hip or knee arthroplasty for OA Key exclusion criteria: receipt of preoperative anticoagulation; medical contraindication to aspirin or enoxaparin; receipt of warfarin Interventions N=5416 aspirin (at a dose of 100 mg/day for 35 days after total hip arthroplasty and for 14 days after total knee arthroplasty) N=3787 enoxaparin (at a dose of 40 mg/day for 35 days after total hip arthroplasty and for 14 days after total knee arthroplasty) Primary outcome Symptomatic venous thromboembolism at day 90 3.5 % 3.45 https://web.pathway.md/studies/recJobn7ummhiY4wp 1/2 6/28/23, 12:23 AM CRISTAL Pathway 2.6 % 1.82 1.7 % Difference exceeding nonferiority margin 0.9 % 0.0 % Aspirin Enoxaparin Difference exceeding nonferiority margin in symptomatic VTE at day 90 (3.45% vs. 1.82%; AD 1.97%, 95% CI 0.54 to 3.41) Secondary outcomes No significant difference in death from any cause at 90 days (0.1% vs. 0.1%; AD 0.05%, 95% CI -0.05 to 0.15) No significant difference in major bleeding at 90 days (0.3% vs. 0.4%; ARD -0.05, 95% CI -0.35 to 0.25) No significant difference in drug adherence (85% vs. 86%; ARD -0.99, 99% CI -0.91 to 1.08) Conclusion In adult patients undergoing hip or knee arthroplasty for OA, aspirin was not noninferior to enoxaparin with respect to symptomatic VTE at day 90. Reference CRISTAL Study Group, Verinder S Sidhu, Thu-Lan Kelly et al. Effect of Aspirin vs Enoxaparin on Symptomatic Venous Thromboembolism in Patients Undergoing Hip or Knee Arthroplasty: The CRISTAL Randomized Trial. JAMA. 2022 Aug 23;328(8):719-727. Open reference URL https://web.pathway.md/studies/recJobn7ummhiY4wp 2/2