Aspirin reduces bleeding risk in patients following hip fracture surgery, but not in hip or knee arthroplasty, according to new research.
The meta-analysis included 1408 participants and looked at randomised trials comparing aspirin to anticoagulants for prevention of VTE following major lower extremity surgery. Anticoagulants featured in the comparisons were vitamin K antagonists, unfractionated heparin, low-molecular-weight heparin, thrombin inhibitors, pentasaccharides and factor Xa/IIa inhibitors. All trials screened participants for DVT post-surgery. The main outcome measures were the rate of proximal DVT that occurred in the popliteal vein and above, bleeding events, and pulmonary embolism. A bleeding event was defined as any need for post-operative blood transfusion or otherwise clinically significant bleeding.
The results showed that the risk of bleeding was 48% lower with aspirin than with anticoagulants. When grouped according to surgery type, risk remained statistically lower in the aspirin group in patients following hip fracture repair, with aspirin reducing bleeding risk by 68% compared to anticoagulation, but not in patients who had a total hip or knee arthroplasty. Overall rates of DVT did not differ statistically between aspirin and anticoagulants. Sub-grouped by type of surgery, there was a non-significant trend favouring anticoagulation following hip fracture repair, but not knee or hip arthroplasty.
The researchers noted that ‘compared with anticoagulation, aspirin may be associated with a higher risk of DVT following hip fracture repair, although bleeding rates were substantially lower’, adding that ‘the lower risk of bleeding with aspirin is likely outweighed by a probable trend toward higher risk of VTE.’