Duration of primary/secondary treatment to prevent recurrent venous thromboembolism: a systematic review and meta-analysis.

It is, however, associated with an increased risk for major bleeding.

然而，它与主要出血风险增加有关

This meta-analysissystematically reviewed the evidence regarding the duration of antithrombotic therapy to assess benefits and harms.

本荟萃分析系统地回顾了关于抗血栓治疗持续时间的证据，以评估其益处和危害。

We systematically searched for randomized controlled trials (RCTs) that compared shorter (3-6 months) with longer (>6 months) courses of anticoagulation for the primary treatment of venous thromboembolism (VTE) or that compared discontinued with indefinite antithrombotic therapy for the secondary prevention of VTE.

我们系统地搜索了比较短期（3-6个月）与长期（>6个月）抗凝治疗的随机对照试验（RCTs），这些试验针对的是静脉血栓栓塞（VTE）的主要治疗，或者比较了中断与无限期抗血栓治疗在VTE二级预防中的效果。

Pairs of reviewers screened the eligible trials and collected data.

审查员成对筛选符合条件的试验并收集数据。

This study included 22 RCTs (11 617 participants).

本研究包括了22项随机对照试验（共11,617名参与者）。

Pooled estimates showed that, for the primary treatment of unprovoked VTE, VTE provoked by chronic risk factors or transient risk factors, treating patients with a longer course (>6 months) of anticoagulation, as opposed to a shorter course (3-6 months), probably reduced recurrent PE (risk ratio [RR], 0.66; 95% confidence interval[CI], 0.42-1.02) and DVT (RR, 0.85; 95% CI, 0.63-1.14), but it was associated with increased mortality (RR, 1.43; 95% CI, 0.85-2.41) (moderate certainty) and a higher risk for major bleeding (RR, 2.02; 95% CI, 1.02-3.98; high certainty).

汇总估计显示，对于未诱发的VTE、由慢性风险因素或短暂风险因素诱发的VTE的一线治疗，与较短疗程（3-6个月）相比，给予患者更长疗程（>6个月）的抗凝治疗可能降低了复发性PE（风险比[RR]，0.66；95%置信区间[CI]，0.42-1.02）和DVT（RR，0.85；95% CI，0.63-1.14），但与增加的死亡率（RR，1.43；95% CI，0.85-2.41）（中等确定性）和更高的主要出血风险（RR，2.02；95% CI，1.02-3.98；高确定性）相关。

For the secondary prevention of unprovoked VTE and VTE provoked by chronic risk factors, when compared with discontinuing treatment, indefinite anticoagulation therapy was associated with decreased mortality (RR, 0.54; 95% CI, 0.36-0.81), a reduction in recurrent PE (RR, 0.25; 95% CI, 0.16-0.41) and DVT (RR, 0.15; 95% CI, 0.10-0.21), and an increase in the risk for bleeding (RR, 1.98; 95% CI, 1.18-3.30), all supported by high certainty.

对于未诱发的VTE和由慢性风险因素诱发的VTE的二级预防，与停止治疗相比，无限期抗凝治疗与降低死亡率（RR，0.54；95% CI，0.36-0.81）、减少复发性PE（RR，0.25；95% CI，0.16-0.41）和DVT（RR，0.15；95% CI，0.10-0.21）相关，并且增加了出血风险（RR，1.98；95% CI，1.18-3.30），所有这些都得到了高确定性的支持。

Indefinite antiplatelet therapy may be associated with decreased mortality (RR, 0.95; 95% CI: 0.53-1.68; low certainty), probably a reduction in recurrent PE (RR, 0.65; 95% CI, 0.41-1.03) and DVT (RR, 0.44; 95% CI, 0.17-1.13) (moderate certainty), and may increase the risk for bleeding (RR, 1.28; 95% CI, 0.48-3.41; low certainty).

长期抗血小板治疗可能与降低死亡率相关（RR, 0.95; 95% 置信区间: 0.53-1.68; 低确定性），可能减少复发性肺栓塞（RR, 0.65; 95% 置信区间, 0.41-1.03）和深静脉血栓形成（RR, 0.44; 95% 置信区间, 0.17-1.13）（中等确定性），并可能增加出血风险（RR, 1.28; 95% 置信区间, 0.48-3.41; 低确定性）。

In summary, for the primary treatment of all types of VTE, shorter (3-6 months) duration of anticoagulation is more beneficial. For the secondary prevention of unprovoked VTE or VTE provoked by chronic risk factors, indefinite antithrombotic treatment is more beneficial.

总结来说，对于所有类型的VTE（静脉血栓栓塞症）的初次治疗，较短的（3-6个月）抗凝治疗更为有益。对于未诱发的VTE或由慢性风险因素诱发的VTE的二级预防，无限期的抗血栓治疗更为有益。