Aspirin was noninferior to low-molecular-weight heparins for thromboprophylaxis in patients with surgically treated extremity fractures or with any pelvic or acetabular fracture, researchers report. The use of aspirin was associated with low incidences of deep-vein thrombosis and pulmonary embolism and low 90-day mortality.
The pragmatic, multicenter, randomized, noninferiority trial included adult patients with a surgically treated fracture of an extremity (hip to midfoot or shoulder to wrist) or any pelvic or acetabular fracture. Participants were randomized to low-molecular-weight heparin (enoxaparin 30 mg twice daily) or aspirin 81 mg twice daily during hospitalization.
Based on a primary outcome of death from any cause at 90 days, the results showed: “A total of 12,211 patients were randomly assigned to receive aspirin (6,101 patients) or low-molecular-weight heparin (6,110 patients). Patients had a mean (± SD) age of 44.6 ± 17.8 years, 0.7% had a history of venous thromboembolism, and 2.5% had a history of cancer. Patients received a mean of 8.8 ± 10.6 in-hospital thromboprophylaxis doses and were prescribed a median 21-day supply of thromboprophylaxis at discharge. Death occurred in 47 patients (0.78%) in the aspirin group and in 45 patients (0.73%) in the low-molecular-weight–heparin group (difference, 0.05 percentage points; 96.2% confidence interval, −0.27 to 0.38; P <0.001 for a noninferiority margin of 0.75 percentage points). Deep-vein thrombosis occurred in 2.51% of patients in the aspirin group and 1.71% in the low-molecular-weight–heparin group (difference, 0.80 percentage points; 95% CI, 0.28 to 1.31). The incidence of pulmonary embolism (1.49% in each group), bleeding complications, and other serious adverse events were similar in the two groups.”
Editorial: “The findings in this trial clearly indicate that guidelines for the prevention of hospital-acquired venous thromboembolism will need to be rewritten to include the option of aspirin in patients with traumatic injuries,” an editorialist writes. “More work is needed to determine whether aspirin should also be considered for venous thromboembolism prophylaxis after other types of surgeries and for nonsurgical patients who have risk factors for venous thromboembolism.”