Elderly patients in ROCKET AF saw equal benefits with less risk of intracranial bleeding with rivaroxaban compared with warfarin. But there was a greater risk of noncranial bleeding in these patients.
In a study published online June 3 in Circulation, researchers proposed that the stable dosage of rivaroxaban (Xarelto, Janssen Pharmaceuticals/Bayer HealthCare) with less need of repeated monitoring and adjustments will make it a more effective anticoagulant treatment for reducing the risk of stroke in patients with nonvalvular atrial fibrillation (AF).
The prespecified analysis used data collected during the international ROCKET AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation) trial to determine the efficacy and safety of rivaroxaban versus warfarin in atrial fibrillation patients 75 years and older. Efficacy was determined by how well each drug was able to prevent stroke and systemic embolism in patients, while safety was defined by bleeding risks.
Results in the elderly patient group were further compared to a group of patients younger than 75 years to note the effect of the aging process on overall effectiveness.
“Since elderly patients with AF bear the highest risk of stroke and greatest susceptibility to adverse drug effects, the balance of risk and benefit is a key therapeutic consideration for older patients,” stated first author Jonathan L. Halperin, MD, of the Icahn School of Medicine at Mount Sinai, N.Y., et al.
For 24 months, 14,264 patients were followed and reviewed for bleeding complications, either ischemic or hemorrhagic stroke, systemic embolism, transit ischemic attack or acute MI. Compliance was reportedly as a little better than half for older patients in either treatment group. Younger patients saw nearly 70 percent compliance.
Over the course of the study, stroke and systemic embolism rates for older patients were at 2.29 percent for those on rivaroxaban vs. 2.85 percent on warfarin. Patients aged 75 years and older had a greater risk of major bleeding on rivaroxaban (4.86 percent) than on warfarin (4.4 percent), while for younger patients, both risk of stroke and major bleeding events was less than half that.
Still, Halperin et al stated, “The main clinical implication of this study is that in elderly patients with nonvalvular AF at high risk of stroke, factor Xa inhibition with rivaroxaban is as effective as adjusted-dose anticoagulation with warfarin. Although rivaroxaban caused more clinically relevant non-major bleeding, it carried less risk of intracranial bleeding, a particular concern in the elderly.”
Jane E. Freedman, MD, of the University of Massachusetts Medical School in Worcester, et al, wrote in an accompanying editorial, “The public health importance atrial fibrillation and stroke in elderly adults remains strong and should direct areas for investigation that may mitigate stroke-related morbidity.” They added, “Clearly needed are innovative approaches that may ultimately facilitate the application of novel preventive, diagnostic, and therapeutic insights into the management of older adults with atrial fibrillation.”
ROCKET AF was funded by Janssen Pharmaceuticals and Bayer HealthCare.