Antithrombotic therapy use in patients with atrial fibrillation before the era of non-vitamin K antagonist oral anticoagulants: the Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) Phase I cohort

Abstract

Aims: The introduction of non-VKA oral anticoagulants (NOACs), which differ from the earlier vitamin K antagonist (VKA) treatments, has changed the approach to stroke prevention in atrial fibrillation (AF). GLORIA-AF is a prospective, global registry programme describing the selection of antithrombotic treatment in newly diagnosed AF patients at risk of stroke. It comprises three phases: Phase I, before the introduction of NOACs; Phase II, during the time of the introduction of dabigatran, the first NOAC; and Phase III, once NOACs have been established in clinical practice.

Methods and results: In Phase I, 1063 patients were eligible from the 1100 enrolled (54.3% male; median age 70 years); patients were from China (67.1%), Europe (EU; 27.4%), and the Middle East (ME; 5.6%). The majority of patients using VKAs had high stroke risk (CHA2DS2-VASc ≥ 2; 86.5%); 13.5% had moderate risk (CHA2DS2-VASc = 1). Vitamin K antagonist use was higher for persistent/permanent AF (47.7%) than that for paroxysmal (23.9%). Most patients in China were treated with antiplatelet agents (53.7%) vs. 27.1% in EU and 28.8% in ME. In China, 25.9% of patients had no antithrombotic therapy, vs. 8.6% in EU and 8.5% in ME.

Conclusion: Phase I of GLORIA-AF shows that VKAs were mostly used in patients with persistent/permanent (vs. paroxysmal) AF and in those with high stroke risk. Furthermore, there were meaningful geographical differences in the use of VKA therapy in the era before the availability of NOACs, including a much lower use of VKAs in China, where most patients either received antiplatelet agents or no antithrombotic treatment.

Keywords: Atrial fibrillation; Oral anticoagulation; Registry; Stroke.

Figure 1

Type and symptom burden of AF.

Figure 2

Antithrombotic treatment pattern by region (all regions). ^aOne patient from Europe and 19 from the Middle East are excluded due to receipt of NOAC. AP, antiplatelet agents.

Figure 3

Antithrombotic treatment pattern by AF type (all regions). ^aSixteen patients with paroxysmal AF and four with permanent AF are excluded from the graph because they received a NOAC.

Figure 4

Antithrombotic treatment pattern by stroke risk (CHA₂DS₂-VASc score) (China). AP, antiplatelet agents; CHA₂DS₂-VASc, congestive heart failure, hypertension, age ≥75 years (doubled), diabetes, stroke (doubled), vascular disease, age 65–74 years, sex category (female).