Risks and benefits of direct oral anticoagulants versus warfarin in a real world setting: cohort study in primary care

Vinogradova, Yana; Coupland, Carol; Hill, Trevor; Hippisley-Cox, Julia

Abstract

Objective: To investigate the associations between direct oral anticoagulants (DOACs) and risks of bleeding, ischaemic stroke, venous thromboembolism, and all cause mortality compared with warfarin.

Design: Prospective open cohort study.

Setting: UK general practices contributing to QResearch or Clinical Practice Research Datalink.

Participants: 132 231 warfarin, 7744 dabigatran, 37 863 rivaroxaban, and 18 223 apixaban users without anticoagulant prescriptions for 12 months before study entry, subgrouped into 103 270 patients with atrial fibrillation and 92 791 without atrial fibrillation between 2011 and 2016.

Main outcome measures: Major bleeding leading to hospital admission or death. Specific sites of bleeding and all cause mortality were also studied.

Results: In patients with atrial fibrillation, compared with warfarin, apixaban was associated with a decreased risk of major bleeding (adjusted hazard ratio 0.66, 95% confidence interval 0.54 to 0.79) and intracranial bleeding (0.40, 0.25 to 0.64); dabigatran was associated with a decreased risk of intracranial bleeding (0.45, 0.26 to 0.77). An increased risk of all cause mortality was observed in patients taking rivaroxaban (1.19, 1.09 to 1.29) or on lower doses of apixaban (1.27, 1.12 to 1.45). In patients without atrial fibrillation, compared with warfarin, apixaban was associated with a decreased risk of major bleeding (0.60, 0.46 to 0.79), any gastrointestinal bleeding (0.55, 0.37 to 0.83), and upper gastrointestinal bleeding (0.55, 0.36 to 0.83); rivaroxaban was associated with a decreased risk of intracranial bleeding (0.54, 0.35 to 0.82). Increased risk of all cause mortality was observed in patients taking rivaroxaban (1.51, 1.38 to 1.66) and those on lower doses of apixaban (1.34, 1.13 to 1.58).

Conclusions: Overall, apixaban was found to be the safest drug, with reduced risks of major, intracranial, and gastrointestinal bleeding compared with warfarin. Rivaroxaban and low dose apixaban were, however, associated with increased risks of all cause mortality compared with warfarin.

Citation

Vinogradova, Y., Coupland, C., Hill, T., & Hippisley-Cox, J. (2018). Risks and benefits of direct oral anticoagulants versus warfarin in a real world setting: cohort study in primary care. BMJ, 362, Article k2505. https://doi.org/10.1136/bmj.k2505

• Journal Article Type: Article
• Acceptance Date: May 22, 2018
• Publication Date: Jul 4, 2018
• Deposit Date: Jul 13, 2018
• Publicly Available Date: Jul 13, 2018
• Journal: BMJ
• Print ISSN: 0959-8138
• Electronic ISSN: 1756-1833
• Publisher: BMJ Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 362
• Article Number: k2505
• DOI: https://doi.org/10.1136/bmj.k2505
• Keywords: Direct oral anticoagulants; DOACS; Warfarin; Primary Care; Bleeding; risks of bleeding; Ischaemic stroke; Venous thromboembolism; All cause mortality
• Public URL: https://nottingham-repository.worktribe.com/output/945365
• Publisher URL: https://www.bmj.com/content/362/bmj.k2505
• Related Public URLs: https://creativecommons.org/licenses/by/4.0/
• Contract Date: Jul 13, 2018