At present, there are few studies on the stability of warfarin anticoagulation therapy. The main evaluation method is SAMe-TT2R2 score, but it has obvious limitations and is not applicable to non-white population. Previous studies have shown that platelet distribution width (PDW) and left atrial diameter (LAD) are closely related to time within therapeutic range (TTR). Whether they can be incorporated into the existing scoring system and improved is worthy of clinical reflection.

To explore the predictive value of modified SAMe-T-PDW2-LAD2 score for the percentage of TTR of common international normalized ratio (INR) for the stability of warfarin anticoagulation therapy.

A total of 164 patients with persistent nonvalvular atrial fibrillation who were treated with warfarin anticoagulation in Jiujiang NO.1 People's Hospital from January 2021 to June 2023 were selected as the research objects. TTR≥65% was defined as high quality anticoagulation. TTR<65% was defined as substandard, that is, the stability of warfarin anticoagulation therapy was not high-quality. According to the above criteria, the patients were divided into two groups: TTR≥65% group (TTR≥65%, 46 cases) and TTR<65% group (TTR<65%, 118 cases). The modified SAMe-T-PDW2-LAD2 score retained the four parameters of gender, age, comorbidities and combined medication in the previous SAMe-TT2R2 score, and the two parameters of race and smoking were deleted. "Increased PDW" and "increased LAD" were replaced by 2 points respectively. The above parameters were collected and compared between the two groups. Binary Logistic regression analysis was used to explore the influencing factors of stable TTR target in warfarin anticoagulation therapy. Receiver operating characteristic (ROC) curves of SAMe-TT2R2 score and modified SAMe-T-PDW2-LAD2 score were plotted to evaluate the TTR target stability of warfarin anticoagulation therapy.

Single factor analysis showed that there were significant differences in age, combined with heart failure, combined with hyperlipidemia, smoking, increased PDW and increased LAD between the two groups (P<0.05). Binary Logistic regression analysis showed that age (OR=0.882, 95%CI=0.812-0.958, P=0.003), increased PDW (OR=0.443, 95%CI=0.282-0.697, P<0.001), and increased LAD (OR=0.031, 95%CI=0.001-0.853, P=0.040) were the influencing factors of achieving stable TTR target on warfarin anticoagulation therapy. There were significant differences in TTR and TTR reaching the target rate between groups with different scores of SAMe-TT2R2 score (P<0.05). The TTR of scores 6 and 7 groups was higher than that of scores 2, 3, 4 and 5 groups (P<0.05). The TTR target rate in the score 7 group was higher than that in the score 2, 3, 4, 5, and 6 groups (P<0.05). There were significant differences in TTR and TTR reaching the target rate among different score groups of modified SAMe-T-PDW2-LAD2 score (P<0.05). The TTR of scores 3, 4, 5, 6, and 7 groups was lower than that of scores 0, 1, and 2 groups (P<0.05). The TTR target rate in the integral 2 group was higher than that in the integral 0, 1, 3, 4, 5, 6, and 7 groups (P<0.05). ROC curve results showed that the area under the ROC curve (AUC) of SAMe-TT2R2 score for evaluating the stability of warfarin anticoagulation therapy TTR target was 0.803 (95%CI=0.737-0.868), the best cut-off value was 5.5, the sensitivity was 1, and the specificity was 0.508. The AUC of modified SAMe-T-PDW2-LAD2 score was 0.814 (95%CI=0.751-0.877), the best cut-off value was 2.5, the sensitivity was 0.848, and the specificity was 0.737.

Age, increased PDW and increased LAD are the influencing factors of achieving stable TTR target in warfarin anticoagulation therapy. There are many limitations of SAMe-TT2R2 score in evaluating the stability of warfarin anticoagulation therapy. The modified SAMe-T-PDW2-LAD2 score has better clinical application value in evaluating the stability of warfarin anticoagulation therapy.

目前关于华法林抗凝治疗稳定性的研究较少，现有主要评估方法为SAMe-TT2R2积分，但该积分具有较为明显的局限性且不适用于非白种人群，前期研究显示血小板分布宽度（PDW）以及左心房内径（LAD）与治疗目标范围内的时间百分比（TTR）的达标具有密切关系，可否将二者纳入现有的积分体系并加以改良运用值得临床深思。

探索改良SAMe-T-PDW2-LAD2积分对华法林抗凝治疗稳定性常用国际标准化比值（INR）在TTR达标的预测价值，以期为改进现有华法林抗凝治疗稳定性的评价方案提供方法学参考。

选取2021年1月—2023年6月就诊于九江市第一人民医院的164例使用华法林抗凝治疗的持续性非瓣膜性心房颤动患者作为研究对象。根据TTR评价界值（65%）将TTR≥65%定义为达标，即华法林抗凝治疗稳定性为高质量抗凝；将TTR<65%定义为未达标，即华法林抗凝治疗稳定性为非高质量抗凝。同时根据上述标准将患者分为两组：TTR达标组（TTR≥65%，46例）和TTR未达标组（TTR<65%，118例）。改良SAMe-T-PDW2-LAD2积分保留了既往SAMe-TT2R2积分中性别、年龄、合并疾病、合并用药这4项参数，并尝试将种族、吸烟这2项参数删除，代替以"PDW升高"和"LAD增大"并分别积分为2分；收集并比较两组患者的上述参数。采用二元Logistic回归分析探讨华法林抗凝治疗稳定性TTR达标的影响因素；分别绘制SAMe-TT2R2积分、改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性TTR达标的受试者工作特征（ROC）曲线。

单因素分析结果显示，两组患者年龄及合并心力衰竭、合并高脂血症、吸烟、PDW升高、LAD增大比例比较，差异有统计学意义（P<0.05）。二元Logistic回归分析结果显示，年龄（OR=0.882，95%CI=0.812~0.958，P=0.003）、PDW升高（OR=0.443，95%CI=0.282~0.697，P<0.001）、LAD增大（OR=0.031，95%CI=0.001~0.853，P=0.040）是华法林抗凝治疗稳定性TTR达标的影响因素。SAMe-TT2R2积分不同分值组TTR、TTR达标率比较，差异有统计学意义（P<0.05）；其中积分6、7分组TTR高于积分2、3、4、5分组（P<0.05）；积分7分组TTR达标率高于积分2、3、4、5、6分组（P<0.05）。改良SAMe-T-PDW2-LAD2积分不同分值组TTR、TTR达标率比较，差异有统计学意义（P<0.05）；其中积分3、4、5、6、7分组TTR低于积分0、1、2分组（P<0.05）；积分2分组TTR达标率高于积分0、1、3、4、5、6、7分组（P<0.05）。ROC曲线结果显示，SAMe-TT2R2积分评价华法林抗凝治疗稳定性TTR达标的ROC曲线下面积（AUC）为0.803（95%CI=0.737~0.868），最佳截断值为5.5分，灵敏度为1，特异度为0.508；改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性TTR达标的AUC为0.814（95%CI=0.751~0.877），最佳截断值为2.5分，灵敏度为0.848，特异度为0.737。

年龄、PDW升高、LAD增大是华法林抗凝治疗稳定性TTR达标的影响因素。SAMe-TT2R2积分评价华法林抗凝治疗稳定性存在较多的局限性，改良SAMe-T-PDW2-LAD2积分评价华法林抗凝治疗稳定性具有较好的临床应用价值。