Enoxaparin as effective as aspirin for lowering symptomatic VTE risk after arthroplasty: JAMA

A secondary analysis of a cluster randomized crossover clinical trial done by The CRISTAL Study Group discovered that there was no difference in mortality after 90 days between patients assigned to enoxaparin versus aspirin for venous thromboembolism (VTE) prevention. The findings of this study were published in The Journal of American Medical Association.

Following hip and knee arthroplasty, ischemic heart disease remains the major cause of death. Aspirin has been postulated as a medication that might lower mortality when administered as venous thromboembolism prophylaxis following these operations due to its antiplatelet and cardioprotective effects. As a result, this study compared aspirin to enoxaparin in terms of lowering 90-day mortality in patients after hip or knee arthroplasty surgeries.

This was a planned secondary analysis of the CRISTAL cluster randomized, crossover, registry-nested trial, which was conducted in 31 Australian hospitals between April 20, 2019, and December 18, 2020. The CRISTAL study sought to establish if aspirin was superior to enoxaparin in preventing symptomatic VTE after hip or knee arthroplasty. The primary research limited the analysis to individuals who had complete hip or knee arthroplasty for osteoarthritis. All adult patients (aged 18 years) receiving any hip or knee arthroplasty operation at participating facilities during the trial are included in this study. Data was analyzed between June 1 and September 6, 2021. The primary endpoint was death within 90 days. The mortality difference between groups was calculated using cluster summary techniques.

The key findings of this study were:

1. A total of 23 458 patients from 31 institutions were involved, with 14 156 assigned to aspirin and 9302 assigned to enoxaparin.

2. Within 90 days of surgery, the aspirin group had a death rate of 1.67% while the enoxaparin group had a mortality rate of 1.53%.

3. The death rate in the subgroup of 21 148 patients with a non fracture diagnosis was 0.49% in the aspirin group and 0.41% in the enoxaparin group.

Reference:

Sidhu, V. S., Kelly, T.-L., Pratt, N., Graves, S. E., Buchbinder, R., Adie, S., Cashman, K., Ackerman, I. N., Bastiras, D., Brighton, R., Burns, A. W. R., Chong, B. H., Ellis, A., … Harris, I. A. (2023). Effect of Aspirin vs Enoxaparin on 90-Day Mortality in Patients Undergoing Hip or Knee Arthroplasty. In JAMA Network Open (Vol. 6, Issue 6, p. e2317838). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2023.17838