Dabigatran Bleeding Complications Are Not More Common than Expected

Dabigatran is safer than warfarin, and reporting bias explains high numbers of reported complications.

Dabigatran was approved in October 2010 for stroke prevention in patients with atrial fibrillation. Following its approval, the U.S. Food and Drug Administration (FDA) received an unexpected number of reports of bleeding complications, and news media raised the possibility that this agent was not as safe in general use as it had been in controlled clinical trials. In December 2011, the FDA issued a drug safety communication warning of bleeding risks (http://www.fda.gov/drugs/drugsafety/ucm282724.htm).

Using an insurance claims database, FDA investigators quantified bleeding events in dabigatran and warfarin recipients from the date of approval through December 2011. The rate of gastrointestinal hemorrhage was 1.6 per 100,000 days of treatment for dabigatran versus 3.1 for warfarin. Corresponding figures for intracranial hemorrhage were 0.9 and 1.9.

In a separate study, authors at a Boston emergency department describe a prospective case series of 15 patients with dabigatran-associated bleeding and 123 with warfarin-associated bleeding from June to December 2011. Review of medical records for all dabigatran cases and 25 warfarin cases showed dabigatran recipients had a shorter hospital stays (3.5 vs. 6.0 days), older age (77 vs. 70 years), more gastrointestinal bleeding (80% vs. 48%), less intracranial bleeding (0% vs. 32%), and more acute renal failure (53% vs. 42%).

CITATION(S):

Southworth MR et al. Dabigatran and postmarketing reports of bleeding. N Engl J Med 2013 Apr 4; 368:1272. 

Berger R et al. Hemorrhagic complications in emergency department patients who are receiving dabigatran compared with warfarin. Ann Emerg Med 2013 Apr; 61:475.