Dentali Francesco, Fantoni Chiara
Department of Clinical Medicine, University of Insubria - Ospedale di Circolo, Via Guicciardini 9, 21100, Varese, Italy.
Intern Emerg Med. 2017 Aug;12(5):565-567. doi: 10.1007/s11739-017-1695-8. Epub 2017 Jun 27.
The international guidelines recommend the use of direct oral anticoagulants (DOACs) over vitamin K antagonists for anticoagulation long-term therapy in patients diagnosed with venous thromboembolism (VTE), and for stroke prevention in patients with non-valvular atrial fibrillation (AF). Efficacy and safety of DOACS have been extensively evaluated in large phase III trials. According to the product label, dose reductions of DOACs are recommended for patients with AF and renal impairment, low body weight and concomitant use of interfering medications. Except for Edoxaban, dose reductions of DOACs are not recommended in patients with VTE based on the same indications for AF patients. The aim of this article is to discuss the indication of a lower DOAC dose in some patients with VTE. Observational studies and randomized control trials (RCTs) show that patients with AF are usually older, more often have chronic diseases, and more often are treated with several concomitant medications, potentially increasing their haemorrhagic risk. Furthermore, many VTE patients need a shorter period of anticoagulation therapy than AF patients. In real-life studies, VTE patients treated with inappropriate DOAC doses present a higher rate of VTE recurrence, and the same risk of bleeding compared to those treated with the correct dose. In light of this evidence, the use of lower DOAC dose in patients with VTE does not appear reasonable and may be potentially dangerous.
国际指南推荐，对于诊断为静脉血栓栓塞（VTE）的患者，在进行长期抗凝治疗时，以及对于非瓣膜性心房颤动（AF）患者进行卒中预防时，应使用直接口服抗凝剂（DOACs）而非维生素K拮抗剂。DOACs的有效性和安全性已在大型III期试验中得到广泛评估。根据产品标签，对于患有AF和肾功能损害、低体重以及同时使用干扰药物的患者，建议减少DOACs的剂量。除依度沙班外，基于与AF患者相同的适应症，不建议对VTE患者减少DOACs的剂量。本文的目的是讨论在一些VTE患者中使用较低剂量DOACs的适应症。观察性研究和随机对照试验（RCTs）表明，AF患者通常年龄较大，更常患有慢性疾病，并且更常同时接受多种药物治疗，这可能会增加他们的出血风险。此外，许多VTE患者所需的抗凝治疗时间比AF患者短。在现实生活研究中，接受不适当DOAC剂量治疗的VTE患者VTE复发率较高，与接受正确剂量治疗的患者相比，出血风险相同。鉴于这一证据，在VTE患者中使用较低剂量的DOACs似乎不合理，而且可能具有潜在危险性。
