Comparison of international normalized ratio audit parameters in patients enrolled in GARFIELD-AF and treated with vitamin K antagonists
British Journal of Haematololgy
Vitamin K antagonist (VKA) therapy for stroke prevention in atrial fibrillation (AF) requires monitoring of the international normalized ratio (INR). The Authors evaluated the agreement between two INR audit parameters, frequency in range (FIR) and proportion of time in the therapeutic range (TTR), using data from a global population of 17,168 patients with newly diagnosed non-valvular AF, the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
The Authors found that the difference between FIR and TTR explains 17.4% of the total variability of measurements. These results suggest that FIR and TTR are not equivalent and cannot be used interchangeably.
Reference
Fitzmaurice DA, Accetta G, Haas S, Kayani G, Lucas Luciardi H, Misselwitz F, Pieper K, Ten Cate H, Turpie AG, Kakkar AK; GARFIELD-AF Investigators. Tondo C tra i collaboratori. Comparison of international normalized ratio audit parameters in patients enrolled in GARFIELD-AF and treated with vitamin K antagonists. Br J Haematol 2016 Apr 12. [Epub ahead of print]