Methavigul Komsing, Boonyapisit Warangkna
J Med Assoc Thai. 2014 Dec;97(12):1274-80.
To determine the optimal International Normalized Ratio (INR) level in Thai atrialfibrillation (AF) patients who received warfarin.
This retrospective study enrolled 230 AF patients that received warfarin in Siriraj Hospital between January 1, 2005 andDecember 31, 2009 and collected the INR level at the time of the event, the numbers of ischemic stroke, and bleeding events. The incidence density of ischemic stroke or bleeding events was calculated by dividing the number of ischemic stroke or bleeding event in each INR level with the summation of the time that each patient stayed in each INR group. The patients with a prosthetic valve were excluded. The INR range was classified into six groups (less than 1.5, 1.5 to 1.9, 2.0 to 2.4, 2.5 to 2.9, 3.0 to 3.4, and greater than 3.4). The optimal INR level was defined as the lowest incidence density of ischemic stroke and bleeding complications.
Two hundred thirty AF patients (the mean age 68 ± 12 years) were enrolled, contributing to 737.54 patient-years of observation period. Of the 230 patients, nine patients experienced 12 ischemic events (1.6 per 100 patient-years) and 54 patients experienced 57 bleeding events (7.7 per 100 patient-years). The percentage of patient-time spent within INR 2 to 3, INR less than 2, and INR more than 3 were 40.75, 46.22, and 13.03%, respectively. The INR level more than 3.4 increased both major and minor bleeding events (p = 0.001). The INR level of 3.0 to 3.4 increased the minor bleeding events (p = 0.03). The INR level less than 1.5 increased incidence of ischemic stroke (p = 0.03). The overall event rate was lowest in the INR range from 1.5 to 2.9, which is significantly different from that of lNR more than 2.9 (p < 0.0001), but trend lower than INR less than 1.5 without being statistically significant (p = 0.198).
An INR of 1.5-2.9 appeared to be associated with the lowest incidence rate of bleeding or ischemic stroke in a cohort of Thai AFpatients receiving warfarin therapy for stroke prevention.
确定接受华法林治疗的泰国房颤（AF）患者的最佳国际标准化比值（INR）水平。
这项回顾性研究纳入了2005年1月1日至2009年12月31日期间在诗里拉吉医院接受华法林治疗的230例AF患者，并收集了事件发生时的INR水平、缺血性卒中数量和出血事件。缺血性卒中和出血事件的发病密度通过将每个INR水平的缺血性卒中和出血事件数量除以每个患者在每个INR组停留时间的总和来计算。排除有人工瓣膜的患者。INR范围分为六组（小于1.5、1.5至1.9、2.0至2.4、2.5至2.9、3.0至3.4以及大于3.4）。最佳INR水平定义为缺血性卒中和出血并发症的最低发病密度。
纳入230例AF患者（平均年龄68±12岁），观察期为737.54患者年。在这230例患者中，9例患者发生12次缺血性事件（每100患者年1.6次），54例患者发生57次出血事件（每100患者年7.7次）。INR在2至3、INR小于2以及INR大于3的患者时间百分比分别为40.75%、46.22%和13.03%。INR大于3.4会增加严重和轻微出血事件（p = 0.001）。INR为3.0至3.4会增加轻微出血事件（p = 0.03）。INR小于1.5会增加缺血性卒中发生率（p = 0.03）。总体事件发生率在INR范围1.5至2.9时最低，与INR大于2.9时显著不同（p < 0.0001），但低于INR小于1.5时，差异无统计学意义（p = 0.198）。
在一组接受华法林预防卒中治疗的泰国AF患者中，INR为1.5 - 2.9似乎与出血或缺血性卒中的最低发生率相关。
