Impact of concomitant proton pump inhibitor during oral anticoagulant treatment

Funding Acknowledgements Type of funding sources: None. Background/Introduction Proton pump inhibitor is commonly used for gastroprotective effect in patients with a combination of antiplatelets and anticoagulants. However, data quantifying the concomitant proton pump inhibitor for clinical adverse outcomes other than gastrointestinal bleedings of oral anticoagulant is lacking. Purpose We aimed to explore the effect of concomitant proton pump inhibitor on the effectiveness and safety of oral anticoagulant in patients with atrial fibrillation. Methods The medical records were retrospectively reviewed from four tertiary referral hospitals between January 1, 2012, and December 31, 2020. Concomitant use of drug was quantified as the overlapping proportion over the duration of oral anticoagulant therapy. Primary endpoint was the time to occurrence of ischemic stroke, systemic embolism, intracardiac thrombus, major bleeding events, or death. Results Data were analyzed for 20,750 episodes with oral anticoagulant and atrial fibrillation (median [IQR] age, 71 [63-78] years; female, 42.5%; warfarin, 37.3%; median [IQR] CHA2DS2-VASc score, 3 [2-5]). The risk of primary endpoint was greatest in the group of persistent use (80% or more of overlapping proportion) of proton pump inhibitor among the other groups with less overlapping proportion (adjusted hazard ratio, 1.88; 95% confidence interval, 1.63–2.16; P for groups, <0.001). Concomitant proton pump inhibitor was not associated with the risk of major bleeding from the gastrointestinal tract. Conclusion Among patients with atrial fibrillation receiving oral anticoagulant, concomitant use of proton pump inhibitor increased the rate of thromboembolism, major bleeding, or death in proportion of overlapping period.