Analysis · Health
What a Bleeding Safety Study Counts—and What It Can Miss
By AWEI · AI-compiled · Published · Analysis prepared · 1 source · doi.org
Of 478 rivaroxaban users identified with major bleeding, 423 had gastrointestinal bleeding and 36 had bleeding inside the skull. Yet nine of the 14 deaths during bleeding hospitalizations involved intracranial bleeding. In this study, the most frequent bleeding site and the site accompanying most hospital deaths differed.
Sally Tamayo and colleagues reported these findings in 2015 using US Department of Defense health records. Their retrospective observational study covered 27,467 people with nonvalvular atrial fibrillation from January 2013 through March 2014. It had no comparison group receiving another anticoagulant and did not randomly assign treatment.
The researchers reconstructed exposure from prescription dispensings, accounting for early refills and gaps. They counted qualifying bleeds during rivaroxaban exposure and for seven days after discontinuation. A previously validated algorithm identified bleeding hospitalizations through diagnosis and procedure codes, excluding trauma-related events. Dispensing records could not confirm that patients actually took the drug.
They identified 496 bleeding events in 478 patients. Using each patient’s first event and accumulated time at risk produced a rate of 2.86 per 100 person-years. Repeat bleeds contributed to the event total but not to that incidence calculation. The headline rate therefore did not capture the full burden of recurrent bleeding.
The hospital-based definition also shaped what could be seen. Sudden fatal bleeding at home could be missed; coded cases were not individually adjudicated, and the definition differed from clinical trial definitions. Only 14 hospital deaths were recorded, limiting precision. These records establish temporal associations, not that rivaroxaban caused each bleed or death. Janssen Scientific Affairs and Bayer HealthCare funded the study.
The practical lesson is to read a safety rate alongside its counting rules: which events qualify, whether recurrences count, and where deaths are captured. This study describes an important pattern in one insured population, but cannot rank anticoagulants by safety or estimate an individual’s outcome.
Sources used for this article (1)
Direct links to the publisher reports used to prepare this article.
- Source 1
- Characterizing Major Bleeding in Patients With Nonvalvular Atrial Fibrillation: A Pharmacovigilance Study of 27 467 Patients Taking Rivaroxaban Sally Tamayo, W. Frank Peacock, Manesh R. Patel …
