K. G. Jebsen Thrombosis Research and Expertise Center (TREC), Department of Clinical Medicine, UiT - the Arctic University of Norway, Tromsø, Norway.
Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway.
J Thromb Haemost. 2018 Jul;16(7):1327-1335. doi: 10.1111/jth.14130. Epub 2018 May 27.
Essentials Competing risk by death may lead to overestimation of venous thromboembolism (VTE) risk in cancers. We assessed the risk of VTE in cancer with and without accounting for competing risk by death. The risk of VTE was influenced by the mortality rate and the time since cancer diagnosis. Competing risk by death should be taken into account when exploring VTE risk in cancer.
Background Venous thromboembolism (VTE) is a common complication in cancer, and studies have suggested that aggressive cancers create the highest risk of VTE. However, competing risk by death may result in overestimation of VTE risk in patients with cancers associated with high mortality. Therefore, we estimated the risk of VTE by cancer site, accounting for the differential mortality between cancers. Methods The Scandinavian Thrombosis and Cancer cohort included 144 952 participants followed from 1993-1997 to 2008-2012. Incidence rates, cause-specific hazard ratios (HRs) and subdistribution HRs (SHRs) were assessed for overall cancer and by cancer site according to time intervals since cancer diagnosis. Results During follow-up, 14 272 subjects developed cancer, and 567 had cancer-related VTE. In cause-specific analyses, the VTE risk was highest in the first 6 months after cancer diagnosis (HR 17.5, 95% confidence interval [CI] 15.1-20.3), and declined rapidly thereafter. However, when mortality was taken into account, the risk was similar in the periods 6 months before (SHR 4.8, 95% CI 3.6-6.4) and 6 months after (SHR 4.6, 95% CI 3.9-5.4) cancer diagnosis. The range of the 2-year cumulative VTE incidence rates was substantially narrowed for all cancer sites after competing risk by death was taken into account (from 1-10% to 1-4%). Conclusion VTE risk by cancer site was influenced by the mortality rate and the time since cancer diagnosis. Our findings suggest that the cancer itself is a major contributor to VTE risk, and that competing risk by death should be taken into account when VTE risk in cancer is explored.
死亡竞争风险可能导致癌症患者静脉血栓栓塞症（VTE）风险的高估。本研究旨在评估考虑与不考虑死亡竞争风险时癌症患者的 VTE 风险。VTE 的风险受到死亡率和癌症诊断后时间的影响。在探索癌症患者的 VTE 风险时，应考虑死亡竞争风险。
静脉血栓栓塞症（VTE）是癌症的常见并发症，研究表明侵袭性癌症会导致 VTE 风险最高。然而，死亡竞争风险可能导致与高死亡率相关的癌症患者的 VTE 风险被高估。因此，我们按癌症部位估计 VTE 的风险，同时考虑癌症之间的死亡率差异。
斯堪的纳维亚血栓形成和癌症队列纳入了 144952 名参与者，随访时间从 1993-1997 年至 2008-2012 年。根据癌症诊断后时间间隔，评估总体癌症和癌症部位的发病率、癌症特异性危险比（HR）和亚分布 HR（SHR）。
在随访期间，14272 名受试者发生癌症，567 名受试者发生癌症相关 VTE。在癌症特异性分析中，癌症诊断后 6 个月内 VTE 风险最高（HR 17.5，95%置信区间[CI]15.1-20.3），此后迅速下降。然而，当考虑死亡率时，癌症诊断前 6 个月（SHR 4.8，95%CI 3.6-6.4）和后 6 个月（SHR 4.6，95%CI 3.9-5.4）的风险相似。考虑到死亡竞争风险后，所有癌症部位的 2 年累积 VTE 发生率范围显著缩小（从 1-10%缩小至 1-4%）。
癌症部位的 VTE 风险受到死亡率和癌症诊断后时间的影响。本研究结果表明，癌症本身是 VTE 风险的主要因素，在探索癌症患者的 VTE 风险时，应考虑死亡竞争风险。
