ASPIRE
Trial question
What is the role of low-dose aspirin in patients who have had a first episode of unprovoked VTE and have a high risk of recurrence after anticoagulants are discontinued?
Study design
Multi-center
Double blinded
RCT
Population
Characteristics of study participants
46.0% female
54.0% male
N = 822
822 patients (375 female, 447 male)
Inclusion criteria: patients who had completed initial anticoagulant therapy after a first episode of unprovoked VTE
Key exclusion criteria: first unprovoked episode of VTE > 2 years before enrollment; indication or contraindication for the use of aspirin, other antiplatelet therapy, or a nonsteroidal antiinflammatory drug; indication for continuing oral anticoagulation therapy; or other medical problems that would interfere with participation in the trial or limit life expectancy
Interventions
N=411 aspirin (100 mg PO once daily, for up to 4 years)
N=411 placebo (matching placebo PO once daily, for up to 4 years)
Primary outcome
Incidence of recurrent venous thromboembolism
4.8
6.5
6.5 % / y
4.9 % / y
3.3 % / y
1.6 % / y
0.0 % / y
Aspirin
Placebo
No significant difference ↔
No significant difference in the incidence of recurrent VTE (4.8% / y vs. 6.5% / y; HR 0.74, 95% CI 0.52 to 1.05)
Secondary outcomes
Significant decrease in the incidence of major vascular events (5.2% / y vs. 8% / y; HR 0.66, 95% CI 0.48 to 0.92)
Significant decrease in the incidence of VTE, myocardial infarction, stroke, major bleeding, or death (6% / y vs. 9% / y; HR 0.67, 95% CI 0.49 to 0.91)
Safety outcomes
No significant difference in major or clinically relevant nonmajor bleeding or serious adverse events.
Conclusion
In patients who had completed initial anticoagulant therapy after a first episode of unprovoked VTE, aspirin was not superior to placebo with respect to the incidence of recurrent VTE.
Reference
Brighton TA, Eikelboom JW, Mann K et al. Low-dose aspirin for preventing recurrent venous thromboembolism. N Engl J Med. 2012 Nov 22;367(21):1979-87.
Open reference URL