Man or woman, prescription rates for stroke-preventing anticoagulants were no different for patients with nonvalvular atrial fibrillation in a global study. However, on the whole the same anticoagulation rates showed inadequate thromboprophylaxis in the majority of patients.

Data from the GARFIELD-AF (Global Anticoagulant Registry in the FIELD – Atrial Fibrillation) provided the basis of this analysis. The registry included data from 858 sites from 30 countries on patients with newly diagnosed nonvalvular atrial fibrillation and one or more stroke risk factors. While the registry is ongoing, they used cases from 2010 through 2013.

Gregory Y.H. Lip, MD, of the University of Birmingham Center for Cardiovascular Science at the City Hospital in Birmingham, England, and colleagues suspected a difference would exist between anticoagulation between men and women, favoring men. What they found instead was that rates were not different overall nor in patients with CHADS2 scores of two or more.

Approximately a third of patients – male or female – at high or moderate to high risk for stroke were not receiving thromboprophylaxis. Instead, around 40 percent of patients who would not be considered candidates according to guidelines received anticoagulation. They also noted that those at high risk for bleeding were more likely to receive antiplatelet therapy alone or combination antithrombotic therapy than those at low risk.

Stroke prevention, Lip et al wrote, needed to improve, including assessment of risk among patients and ensuring adequate treatment for those at most risk.

“The presence of comorbid conditions such as coronary artery disease cannot, alone, account for the high rates of use of combination therapy in men and women at high risk of bleeding. Furthermore, a high HAS-BLED [Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio (INR), Elderly, Drugs/alcohol concomitantly] score per se should not be used to withdraw or preclude the use of anticoagulants; rather, it should be used to identify patients at higher risk of bleeding and to correct any potentially reversible risk factors for this event, and, in particular, to reconsider the use of combination antithrombotic therapy,” they wrote.

The study was published online Feb. 24 in Circulation: Cardiovascular Quality and Outcomes.