F10 and atrial fibrillation: In the J-ROCKET AF (Japanese Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation) study, the principal safety endpoints (major bleeding plus nonmajor clinically relevant bleeding) in the rivaroxaban arm were significantly increased in the elderly (age ≥75 years) (HR: 1.49; 95% CI: 1.02-2.16) but not in the non-elderly (age <75 years) (HR: 0.89; 95% CI: 0.64-1.23) when compared with the warfarin arm (P for interaction = 0.04).82