Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
Thromb Res. 2013;132(6):724-8. doi: 10.1016/j.thromres.2013.09.012. Epub 2013 Sep 16.
Current anticoagulation guidelines suggest that optimal anticoagulation duration for unprovoked venous thromboembolism is determined by an individual risk assessment, balancing risks of anticoagulation bleeding with venous thromboembolism recurrence. Among individuals heterozygous for the factor V Leiden mutation, while venous thromboembolism recurrence risk is greater, the risk for bleeding is recognized to be lower, suggesting longer duration anticoagulation could be considered.
The objective of this study was to compare standard vs. lifelong anticoagulation in 20-year-old factor V Leiden heterozygotes with unprovoked venous thromboembolism.
A Markov state-transition model was used, incorporating risks of major, minor, and fatal anticoagulation bleeding, bleeding and thromboembolism morbidity and mortality, and quality of life utilities. Model parameter values favoring lifelong anticoagulation in factor V Leiden heterozygotes were determined in sensitivity analyses. Outcomes were in quality-adjusted life years, discounted at 3% per year.
In general population groups with odds ratios for venous thromboembolism recurrence and anticoagulation bleeding of 1.0, a short-term anticoagulation strategy gained 0.09 quality-adjusted life years more than a lifelong anticoagulation strategy. By contrast, in factor V Leiden heterozygotes, lifetime anticoagulation was favored if their relative risk of venous thromboembolism was greater than 1.07 or their relative risk for bleeding was less than 0.91. Results were relatively insensitive to individual variation in other parameter values.
Lifelong anticoagulation may benefit individuals heterozygous for factor V Leiden and previous idiopathic venous thromboembolism. Studies assessing bleeding risk with anticoagulation in factor V Leiden heterozygotes and the costs of indefinite anticoagulation are needed to determine if lifelong anticoagulation is the optimal strategy.
目前的抗凝指南建议，对于无诱因的静脉血栓栓塞症，最佳抗凝持续时间取决于个体风险评估，在权衡抗凝出血风险与静脉血栓栓塞症复发风险之间取得平衡。在因子 V 莱顿突变杂合子中，虽然静脉血栓栓塞症复发风险更高，但出血风险被认为较低，这表明可以考虑更长时间的抗凝。
本研究旨在比较有诱因的静脉血栓栓塞症的因子 V 莱顿杂合子中标准抗凝与终身抗凝。
采用马尔可夫状态转移模型，纳入大出血、小出血和致命抗凝出血、出血和血栓栓塞发病率和死亡率以及生活质量效用的风险。在敏感性分析中确定了有利于因子 V 莱顿杂合子终身抗凝的模型参数值。结果以质量调整生命年来表示，每年贴现率为 3%。
在静脉血栓栓塞症复发和抗凝出血的比值比为 1.0 的一般人群中，短期抗凝策略比终身抗凝策略多获得 0.09 个质量调整生命年。相比之下，如果因子 V 莱顿杂合子的静脉血栓栓塞症风险比大于 1.07 或出血风险比小于 0.91，则终身抗凝是有利的。结果对其他参数值的个体差异相对不敏感。
终身抗凝可能对因子 V 莱顿突变和既往特发性静脉血栓栓塞症的杂合子个体有益。需要评估因子 V 莱顿杂合子中抗凝出血风险和无限期抗凝的成本，以确定终身抗凝是否是最佳策略。
