Low-Dose Aspirin is Safe and Effective for Prevention of Venous Thromboembolism after Femoral Neck Fracture.

Introduction: Although patients who undergo arthroplasty for hip fractures are at high risk of venous thromboembolism (VTE), current guidelines do not specify the optimal VTE prophylactic agent. Recent evidence demonstrates that aspirin (ASA) may be safe and effective for VTE prevention in these patients. The purpose of this study was to determine the safety and efficacy of low-dose ASA (81 mg) compared to non-ASA agents after arthroplasty for femoral neck fracture.

Methods: A total of 36,576 patients who underwent arthroplasty for femoral neck fracture from January 2012 through December 2023 were identified in a national database. Patients were stratified by baseline VTE risk into high-risk and standard-risk groups and further categorized based on the type of VTE prophylaxis received - low-dose ASA only or non-ASA prophylaxis only. Rates and odds of deep vein thrombosis (DVT), pulmonary embolism (PE), and adverse events, including bleeding, blood transfusion requirements, and emergency department visits, were assessed in the 90-day postoperative period for propensity-matched cohorts.

Results: Compared to non-ASA prophylaxis, use of low-dose ASA only was associated with significantly lower odds of DVT in both high-risk (odds ratio [OR]: 0.46; 95% confidence interval [CI]: 0.30 to 0.69) and standard-risk (OR: 0.37; 95% CI: 0.18 to 0.76) groups, and lower odds of PE in high-risk patients (OR: 0.27; 95% CI: 0.14 to 0.55). There were no significant differences in odds of PE in standard-risk patients (OR: 0.71; 95% CI: 0.32 to 1.61). Low-dose ASA was associated with lower odds of bleeding events, blood transfusion requirements, and emergency department visits.

Conclusions: Use of low-dose ASA is safe and effective in preventing VTE in patients undergoing arthroplasty for femoral neck fracture. As this population is at higher risk of mortality, prospective studies comparing VTE prophylaxis regimens are necessary to further improve clinical outcomes.