December 28th, 2011
No Mortality Benefit of Low-Molecular-Weight Heparin in Acutely Ill Patients
Although venous thromboembolism (VTE) is a serious problem for acutely ill patients in the hospital, a new study published in the New England Journal of Medicine failed to find any improvement in mortality associated with thromboprophylaxis.
Ajay Kakkar and the LIFENOX investigators randomized 8307 acutely ill patients to receive enoxaparin or placebo for 10 days. All patients wore elastic stockings with graduated compression.
The two groups did not differ significantly in 30-day mortality or major bleeding:
- 30-day mortality: 4.9% in the enoxaparin group versus 4.8% in the placebo group (P=0.83)
- major bleeding: 0.4% versus 0.3%, respectively (P=0.35)
The findings, the authors write, “appear to be counterintuitive, given the fact that pharmacologic prophylaxis has been shown to reduce the risk of venous thromboembolism, including asymptomatic deep-vein thrombosis, by at least 45% in hospitalized, acutely ill medical patients.” But, they write in the conclusion, the results do not mean that thromboprophylaxis is not worthwhile:
Pharmacologic thromboprophylaxis continues to have proven benefits in preventing venous thromboembolism, thus reducing the need for the treatment of symptomatic venous thromboembolism with high doses of anticoagulant agents over a prolonged period of time. Furthermore, venous thromboembolism can lead to nonfatal complications such as the post-thrombotic syndrome and chronic thromboembolic pulmonary hypertension, which are often not treated successfully.