As part of an ongoing investigation of the safety of blood thinners, the US Food and Drug Administration (FDA) has released results from a large study comparing the relative risks of warfarin with those of dabigatran, a newer product. Analyses of adverse event reports submitted to the FDA have found unexpectedly high rates of bleeding and other adverse events as dabigatran prescribing has increased.

The study, which examined records for 134鈥�000 Medicare patients aged 65 years or older, found that compared with warfarin, dabigatran use is associated with a lower risk of stroke, brain hemorrhage, and death (). However, dabigatran is associated with a higher rate of major gastrointestinal bleeding than warfarin. The study found that both drugs had about the same risk of myocardial infarction. Based on these results, the agency still considers dabigatran 鈥渢o have a favorable benefit-to-risk profile.鈥�