International Circulation: The RE-LY trial showed that dabigatran is useful as an alternative to warfarin for preventing stroke and systemic thromboembolism in atrial fibrillation and according to the Focused Update on the Management of Patients with Atrial Fibrillation， the update on dabigatran has been recommended as a Class I. How should the clinician use that recommendation of a Class I drug that they can administer?
　　《国际循环》：RE-LY试验证明，在心房颤动中，达比加群作为华法林的一种替代药物对预防卒中和体循环栓塞是有用的。根据2011年心房颤动患者治疗更新，达比加群已经作为I类推荐药物。临床医生应如何应用指南指导临床决策？
　　Dr. Ezekowitz: What the clinical trial evidence shows is， in aggregate， dabigatran at 150 is a better drug than warfarin at an INR of 2 to 3. The question among the elderly depends on what dose you would eventually use. My read of the data is that patients over the age of 75 or 80 (depending on how you cut the data) have much fewer GI bleeds using the 150 dose. In fact the GI bleeding rates based on RE-LY are comparable to the bleeding rates you see with warfarin. In that patient base， there is no difference in the reduction of intracranial hemorrhages and the primary events， strokes， remain reduced in the high risk patients. So you can make a case for using the lower dose， the 110mg bid dose， in the older populations particularly in China where Chinese physicians claim that the overall dose of all drugs among their patients should be lower than in Caucasian patients. This is their clinical observation. They also maintain that the INRs for warfarin should be lower among the Chinese and there is a genetic basis for that which has been identified in the last five years， that the Chinese do have genetic variance which would indicate that the average milligram dose of Coumadin should be lower in Chinese than in Caucasians.
　　Dr. Ezekowitz：临床试验证据显示，达比加群150 mg优于华法林（INR 2.0～3.0）。老年人的用药问题取决于你最终会使用什么剂量。我对这一数据的解读是，年龄＞75或80岁的患者（取决于你如何分割数据）使用150 mg的剂量胃肠道出血也较少。实际上，基于RE-LY试验，达比加群胃肠道出血的发生率与华法林相当。一般患者在颅内出血、主要事件和卒中的降低上无差异，高危患者也是如此。 因此对于老年群体，尤其是在中国这样一个医生主张所用药物的总剂量应低于白种人的国家，较低剂量（110 mg bid）的达比加群就有用武之地了，这源于中国医生的临床观察。他们还主张，中国患者口服华法林时，INR的控制范围应更低些，这与遗传因素有关，在过去5年中已得到证实，即中国人的确存在香豆素类的平均剂量应低于白种人的遗传变异。