Impact of Anticoagulant Selection on Mortality in Noncancer Venous Thromboembolism
Overview
In a Medicare cohort of 47,860 patients with noncancer venous thromboembolism (VTE), rivaroxaban was associated with a modestly lower 6-month all-cause mortality compared to warfarin, while apixaban showed no significant difference. These findings were consistent even among patients with kidney or liver disease.
Background
Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, requires anticoagulation treatment. Direct oral anticoagulants (DOACs) such as rivaroxaban and apixaban have largely replaced warfarin due to favorable efficacy and safety profiles demonstrated in clinical trials. However, limited data exist comparing DOACs directly on mortality outcomes, especially in patients with comorbid kidney or liver disease, who were underrepresented in trials. Understanding real-world mortality risks associated with different anticoagulants is critical for optimizing VTE management in older adults.
Data Highlights
Anticoagulant
Adjusted Hazard Ratio (HR) for 6-month Mortality
95% Confidence Interval
Rivaroxaban vs Warfarin
0.82
0.76-0.90
Apixaban vs Warfarin
0.96
0.87-1.07
Apixaban vs Rivaroxaban
1.14
1.01-1.28
Key Findings
Among 47,860 Medicare beneficiaries with incident noncancer VTE, 3,422 deaths occurred within 6 months of anticoagulant initiation.
Rivaroxaban use was associated with an 18% lower adjusted risk of death compared to warfarin (HR 0.82; 95% CI 0.76-0.90).
Apixaban showed no significant mortality difference compared to warfarin (HR 0.96; 95% CI 0.87-1.07).
Direct comparison between apixaban and rivaroxaban suggested a slightly higher mortality risk with apixaban (HR 1.14; 95% CI 1.01-1.28).
These mortality associations were consistent in subgroups with kidney disease and liver disease, indicating DOAC safety in these populations.
Overall, mortality risk was similar across oral anticoagulants, though rivaroxaban may confer a modest survival advantage.
Clinical Implications
Clinicians can consider rivaroxaban as a potentially preferable option over warfarin for initial anticoagulation in older patients with noncancer VTE, including those with kidney or liver comorbidities. Apixaban appears to have a comparable safety profile to warfarin regarding mortality. These findings support the safety of DOACs in patients with renal or hepatic impairment, aligning with guideline recommendations but providing real-world evidence to inform anticoagulant selection.
Conclusion
In this large Medicare cohort, rivaroxaban was associated with lower 6-month mortality compared to warfarin, while apixaban showed no significant difference. DOACs appear safe for VTE treatment in patients with kidney or liver disease, supporting their use in these populations.
References
Author/Source/2024 -- Impact of Anticoagulant Selection on Mortality in Initial Management of Noncancer Venous Thromboembolism: Analysis of Medicare Data from 2011 to 2018
