Rivaroxaban chemoprophylaxis following TKA and THA associated with increased risk of bleeding compared to aspirin and enoxaparin

An optimal venous thromboembolism prophylaxis agent should balance efficacy and safety. While rivaroxaban provides effective venous thromboembolism prophylaxis after total joint arthroplasty, it may be associated with higher rates of bleeding.

Piple et al conducted a study to compare the safety and efficacy of rivaroxaban to aspirin and enoxaparin. It was done at Department of Orthopaedic Surgery, Keck School of Medicine of the University of Southern California, Los Angeles, California. The article has been published in 'The Journal of Arthroplasty.'

A large national database was queried for patients who underwent elective primary total hip (THA) or total knee arthroplasty (TKA) who received rivaroxaban, aspirin, or enoxaparin. Multivariate analyses were performed to assess the 90-day risk of bleeding and thromboembolic complications. Among TKA patients identified, 86,721 (10.8%) received rivaroxaban, 408,038 (50.8%) received aspirin, and 108,377 (13.5%) received enoxaparin. Among THA patients, 42,469 (9.5%) received rivaroxaban, 242,876 (54.5%) received aspirin, and 59,727 (13.4%) received enoxaparin.

Key findings of the study were:

• After accounting for confounding factors, rivaroxaban was associated with increased risk of transfusion (TKA: adjusted odds ratio [aOR] = 2.58, P < .001; THA: aOR 1.64, P < .001), pulmonary embolism (TKA: aOR = 1.25, P = .007), and deep vein thrombosis (TKA: aOR = 1.13, P = .022) compared to aspirin.

• Compared to enoxaparin, rivaroxaban was associated with an increased risk of combined bleeding events (TKA: aOR = 1.07, P < .001, THA: aOR = 1.11, P < .001), but decreased risk of combined prothrombotic events (THA: aOR = 0.85, P = .036).

• TKA patients who received their first dose of rivaroxaban on POD0 had higher rates of acute blood loss anemia (22.9 versus 18.7%, P < .001) compared to patients who received their first dose on POD1 or later. After accounting for confounders, POD0 patients were at increased risk for acute blood loss anemia (aOR: 1.32, 95% CI: 1.27-1.37, P < .001), but decreased risk for blood transfusion (aOR: 0.82, CI: 0.72-0.93, P ¼ .002).

The authors concluded that – “These data suggest rivaroxaban is associated with increased risks of bleeding complications and DVT when compared to aspirin following primary TKA and THA. Furthermore, rivaroxaban use was associated with an increased risk of DVT compared to aspirin; however, these findings may be due to unaccounted confounding in the high-risk rivaroxaban cohort. Also, rivaroxaban was associated with similar bleeding and VTE complications when compared to enoxaparin. These data highlight the potential risks associated with rivaroxaban use following TKA and THA should guide optimal DVT prophylaxis agent choice.”

Further reading:

Safety and Efficacy of Rivaroxaban in Primary Total Hip and Knee Arthroplasty Amit S. Piple, Jennifer C. Wang et al The Journal of Arthroplasty https://doi.org/10.1016/j.arth.2023.02