Characterizing Major Bleeding in Patients With Nonvalvular Atrial Fibrillation: A Pharmacovigilance Study of 27 467 Patients Taking Rivaroxaban

Tamayo S, Peacock F, Patel M, et al.
Clin. Cardiol. 2015 (in press); Published online in wileyonlinelibrary.com; DOI:10.1002/clc.22373
 Atrial fibrillation (AF) is associated with a 5-fold risk of stroke [1,2]. For several decades, Vitamin K antagonists (eg, warfarin) have been a standard prophylactic therapy in reducing the risk of stroke in patients with AF. Rivaroxaban is a novel direct factor Xa inhibitor oral anticoagulant to reduce the risk of stroke and systemic embolism in patients who have nonvalvular AF (NVAF).
An inherent risk associated with the use of anticoagulants is bleeding [3,4]. The objective of the present study is to provide longitudinal safety data on major bleeding (MB) among rivaroxaban users with NVAF in a real-world clinical setting. This observational, retrospective study retrieved information from electronic health care records and a cohort of 27467 rivaroxaban users with NVAF was followed for 15 months.

Main results

• Of 27 467 patients receiving rivaroxaban, 496 MB events occurred in 478 patients, an incidence of 2.86 per 100 person-years (95%CI:2.61-3.13).
• Patients with MB were older (mean age of 78.4 vs 75.7 years) compared with non-MB patients, and had higher rates of hypertension (95.6% vs 75.8%), coronary artery disease (64.2% vs 36.7%), heart failure (48.5% vs 23.7%), and renal disease (38.7% vs 16.7%).
• Major bleeding was most commonly gastrointestinal (88.5%) or intracranial (7.5%).
• Fourteen of the 478 patients died during their MB hospitalisation (fatal bleeding rate of 0.08 per 100 person-years; 95%CI: 0.05-0.14).

Conclusions

The present study showed that the MB rate was 2.86 per 100 person-years  and fatal bleeds were rare. Major bleeding was usually gastrointestinal or intracranial in origin. Patients who experienced MB were older and more likely to have comorbidity at baseline. These outcomes are similar to those reported in the in the ROCKET-AF registration trial [3,4], in which the reported MB rates were 3.6 for rivaroxaban and 3.5 for warfarin (per 100 person years) in patients with NVAF.

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References

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 4. Goodman SG, Wojdyla DM, Piccini JP, et al. Factors associated with major bleeding events: insights from the Rivaroxaban Once-Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF). J Am Coll Cardiol. 2014;63:891–900.