Aspirin Just As Good As Other Blood Thinners At Preventing Clots Following Hip, Knee Joint Surgery

The findings of a new study suggest that taking aspirin is just as effective at preventing blood clots following hip and knee replacement surgery as taking more powerful blood thinners, such as Pradaxa and Xarelto.

Researchers from the U.K. published a study this month in the medical journal JAMA Internal Medicine, which found that aspirin was just as effective as Xarelto, Pradaxa, heparin and similar blood thinners for the prevention of venous thromboembolism events (VTE), such as deep vein thrombosis and pulmonary embolism, and had a comparative safety profile.

The findings suggest that aspirin has both the same efficacy and safety profile as those other drugs for preventing blood clots after surgery, but is far more cost effective.

The study looked at 13 randomized clinical trials involving more than 6,000 participants who were given various medications to prevent blood clot-related events following hip or knee replacement surgery. The researchers looked at studies involving aspirin, heparin, clexane, Pradaxa, Xarelto, and warfarin. They looked for complications such as venous thromboembolism, deep vein thrombosis, pulmonary embolism and bleeding events.

According to the findings, the risk of venous thromboembolism was only 12% higher with aspirin compared to the other blood thinners. However, when they looked at the data for total hip replacement (THR) and total knee replacement (TKR) risks separately, they found no statistical difference. The risks for deep vein thrombosis and pulmonary embolism were also nearly identical. In addition, there was no statistically significant difference in the risk of patients suffering major bleeding, wound hematoma, or wound infection.

“In terms of clinical effectiveness and safety profile, aspirin did not differ statistically significantly from other anticoagulants used for VTE prophylaxis after THR and TKR,” the researchers concluded. “Future trials should focus on noninferiority analysis of aspirin compared with alternative anticoagulants and cost-effectiveness.”

The findings come two months after a study was presented to the American Society of Hematology which found that combining aspirin with many of those same drugs, including for the prevention of VTE, led to no increase in benefits, but increased the risk of bleeding events.

Pradaxa and Xarelto are part of a new generation of blood thinners. However, shortly after they hit the market they were linked to serious bleeding events which were often unstoppable due to the lack of a reversal agent. The bleeding problems resulted in tens of thousands of Pradaxa lawsuits and Xarelto lawsuits.

Boehringer Ingelheim, reached a Pradaxa settlement agreement with most plaintiffs in 2014. A global Xarelto settlement was reached in March 2019, resolving nearly all claims.