Aspirin: alternative to warfarin post-VTE?
Low-dose aspirin may offer a suitable alternative to warfarin in patients who have had venous thromboembolism (VTE), suggest the results of a study published in The New England Journal of Medicine.
The treatment failed to reduce the risk of recurrent VTE compared with placebo, but decreased the risk of major vascular events, resulting in an overall improved net clinical benefit, according to the authors.
The study included 822 patients who had experienced a first unprovoked VTE. All patients had completed initial anticoagulant therapy, with 72% receiving it for at least 6 months before the trial.
Over around 3 years of follow-up, 14% of patients assigned to aspirin 100 mg once daily had a recurrent VTE, compared with 18% who took a placebo. The authors estimate that this represents a 26% reduction in the relative risk of recurrent VTE with aspirin, although this was not statistically significant.
However, when they considered secondary outcomes, patients who received aspirin were 34% less likely to have VTE, myocardial infarction, stroke, or cardiovascular death than patients on placebo (5.2 vs 8.0% per year). Furthermore, net clinical benefit, which also included major bleeding or death from any cause, was reduced by 33% in the aspirin group compared with placebo (6.0 vs 9.0% per year).
Vitamin K antagonists such as warfarin are effective in preventing recurrent VTE but patients may discontinue them due to the risk of bleeding and inconvenience, leaving them at risk.
"Aspirin, although substantially less effective than warfarin, provides an attractive alternative because it is simple and inexpensive and its safety profile is well documented," Dr Timothy Brighton (Prince of Wales Hospital, Sydney, Australia) and colleagues conclude.
GP News is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
By Kirsty Oswald