Safety of antithrombotic therapy in East Asian patients

Antithrombotic agents are widely used on the globe for prevention of thrombotic events such as atherothrombotic events and thromboembolic stroke in atrial fibrillation or for prevention and treatment of venous thromboembolism. However, the net clinical benefit of antithrombotic intervention may differ substantially in various sub-population of patients. Here, the authors attempt to address the risk of serious bleeding in East Asian as compared to the other regions of the world. The community-based epidemiological data suggest numerically higher risk of hemorrhage stroke in East Asian as compared to the globe. Importantly, the life-time risk of ischemic stroke in East Asia is higher than that of the globe. Regarding the serious bleeding risk in East Asians with the use of antithrombotic agents, various clinical trials and international registries provided conflicting information. It is hard to draw generalized conclusion, but there are some specific sub-population in East Asian with higher risk of specific serious bleeding events with the use of specific antithrombotic agents such as the risk of intra-cranial bleeding (ICH) with Vitamin K antagonists. Specific characteristics in East Asian such as higher prevalence of lacunar stroke may contribute higher risk of ICH in East Asian, but the detailed mechanism is still to be elucidated. In conclusion, further investigations are necessary to clarify the specific conditions where the risk of serious bleeding events in East Asian patients differ substantially compared to the global. In addition, further understanding of the mechanisms causing the different bleeding response in specific conditions in East Asian is awaited.