MI risk lower with direct oral anticoagulants vs. vitamin K antagonists
Compared with vitamin K antagonists such as warfarin, direct oral anticoagulants were associated with lower risk for MI in patients with nonvalvular atrial fibrillation, according to a retrospective cohort study.
There was no difference in MI risk among the direct oral anticoagulants, researchers reported.
The researchers analyzed 31,739 patients (median age, 74 years; 47% women) with nonvalvular AF from Danish health care registers who began a prescription for a vitamin K antagonist (28%), apixaban (Eliquis, Bristol-Myers Squibb/Pfizer; 27%), dabigatran (Pradaxa, Boehringer Ingelheim; 23%) or rivaroxaban (Xarelto, Janssen; 22%) between January 2013 and June 2016.
The outcome of interest was standardized 1-year risk for MI.
The standardized 1-year risk for MI was higher in patients taking a vitamin K antagonist (1.6%; 95% CI, 1.3-1.8) than in patients taking apixaban (1.2%; 95% CI, 0.9-1.4), dabigatran (1.2%; 95% CI, 1-1.5) or rivaroxaban (1.1%; 95% CI, 0.8-1.3), Christina Ji-Young Lee, MD, from the department of health science and technology at Aalborg University and unit of epidemiology and biostatistics at Aalborg University Hospital in Denmark, and colleagues wrote.
The risk differences for all three direct oral anticoagulants vs. vitamin K antagonists were significant (apixaban, –0.4%; 95% CI, –0.7 to –0.1; dabigatran, –0.4%; 95% CI, –0.7 to –0.03; rivaroxaban; –0.5%; 95% CI, –0.8 to –0.2), according to the researchers.
However, the risk differences between the direct oral anticoagulants were not significant (dabigatran vs. apixaban, 0.04%; 95% CI, –0.3 to 0.4; rivaroxaban vs. apixaban, 0.1%; 95% CI, –0.4 to 0.3; rivaroxaban vs. dabigatran, –0.1%; 95% CI, –0.5 to 0.2), they wrote.
“Furthermore, the results were consistent for patients with and without prior ischemic heart disease and concomitant antiplatelet therapy,” Lee and colleagues wrote.
In a related editorial, Stefan H. Hohnloser, MD, professor of medicine and cardiology and head of the department of electrophysiology at Johann Wolfgang Goethe University in Frankfurt, Germany, and John W. Eikelboom, MD, MBBS, MSc, associate professor of medicine at McMaster University in Hamilton, Ontario, Canada, wrote that the study “helps to settle the dust around an 8-year-old debate concerning the risk of MI in patients receiving [direct oral anticoagulant] therapy (and specifically dabigatran) for stroke prevention in AF. Based on the large and consistent body of evidence now available, clinicians can use dabigatran with even greater confidence in AF patients, including those with a history of coronary artery disease and prior MI.” – by Erik Swain
Disclosures: Lee reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures. Eikelboom and Hohnloser report they have financial ties with multiple pharmaceutical and device companies.