Using Anticoagulants With Antiplatelets Questionable In Some With AF

To their possible detriment, a sizable minority of patients with nonvalvular atrial fibrillation at risk of stroke are receiving oral anticoagulants (OAC) in addition to antiplatelet (AP) drugs, according to a study of data from the Global Anticoagulant Registry in the Field (GARFIELD-AF) registry.

"In the large multinational GARFIELD study we found that approximately one in eight patients with atrial fibrillation are newly prescribed anti-platelet therapy along with anticoagulation, with or without cardiovascular indications for the antiplatelet therapy," Dr. Keith A. A. Fox of the University of Edinburgh told Reuters Health by email.

To learn more about these patients, and how they compared with those not prescribed AP drugs, Dr. Fox and his colleagues analyzed data on more than 24,000 patients in the study. None had previously received OAC or AP therapy.

More than 3,000 patients (12.5%) were given OAC plus AP and the remainder were given OAC alone, the researchers report in JAMA Network Open. The dual-therapy group had a greater prevalence of cardiovascular indications for AP, including acute coronary syndromes (22.0% vs. 4.3%) and coronary-artery disease (39.1% vs. 9.8%),

At 12 months, the dual-therapy group had a significantly higher incidence of stroke (adjusted hazard ratio, 1.49) and bleeding events (aHR, 1.41), and they showed non-significant increases in all-cause mortality (aHR, 1.22) and acute coronary syndrome (aHR, 1.16).

There was no reduction in risk of other clinical outcomes with OAC plus AP versus OAC alone.

Patients on dual-therapy "have higher cardiovascular risks and higher rates of cardiovascular complications. However, having taken account of all measured co-morbidities and treatments, the excess risks of stroke and of bleeding persist," Dr. Fox said.

"The clinical implications," he concluded, "are that concomitant prescription of antiplatelet therapy with anticoagulation for atrial fibrillation should not be performed unless there are clear indications for the additional anti-platelet therapy."

Dr. Anil K. Gehi, director of Cardiac Electrophysiology at the UNC School of Medicine, in Chapel Hill, NC, told Reuters Health by email, "Current guidelines state that dual therapy should be used only in patients with atrial fibrillation and concomitant vascular disease."

However, Dr. Gehi added that recent studies "suggest that even in patients with AF and vascular disease, anticoagulation monotherapy may be adequate. With the caveat that comparative effectiveness analyses from registries will be compromised by selection bias, the study here...adds to the evidence that the role for dual therapy in AF should be limited."

—David Douglas

Source