Division of Angiology and Hemostasis, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland.
Institute of Pharmacology, University of Bern, Bern, Switzerland.
Thromb Haemost. 2018 Jan;118(1):82-89. doi: 10.1160/TH17-06-0403. Epub 2018 Jan 5.
Improved thromboprophylaxis for acutely ill medical patients relies on valid predictions of thrombotic risks. Our aim was to compare the performance of the Improve and Geneva clinical risk assessment models (RAMs), and to simplify the current Geneva RAM.
Medical inpatients from eight Swiss hospitals were prospectively followed during 90 days, for symptomatic venous thromboembolism (VTE) or VTE-related death. We compared discriminative performance and calibration of the RAMs, using time-to-event methods with competing risk modelling of non-VTE death.
In 1,478 patients, the 90-day VTE cumulative incidence was 1.6%. Discrimination of the Improve and Geneva RAM was similar, with a 30-day AUC (areas under the curve) of 0.78 (95% CI [confidence interval]: 0.65-0.92) and 0.81 (0.73-0.89), respectively. According to the Improve RAM, 68% of participants were at low risk (0.8% VTE at 90 days), and 32% were at high risk (4.7% VTE), with a sensitivity of 73%. According to the Geneva RAM, 35% were at low risk (0.6% VTE) and 65% were at high risk (2.8% VTE), with a sensitivity of 90%. Among patients without thromboprophylaxis, the sensitivity was numerically greater in the Geneva RAM (85%) than in the Improve RAM (54%). We derived a simplified Geneva RAM with comparable discrimination and calibration as the original Geneva RAM.
We found comparably good discrimination of the Improve and Geneva RAMs. The Improve RAM classified more patients as low risk, but with possibly lower sensitivity and greater VTE risks, suggesting that a lower threshold for low risk (<2) should be used. The simplified Geneva RAM may represent an alternative to the Geneva RAM with enhanced usability.
为急性病患者改善血栓预防依赖于对血栓风险的有效预测。我们的目的是比较改进和日内瓦临床风险评估模型（RAM）的性能，并简化目前的日内瓦 RAM。
来自瑞士八家医院的住院患者前瞻性随访 90 天，以确定症状性静脉血栓栓塞（VTE）或与 VTE 相关的死亡。我们使用具有非 VTE 死亡竞争风险建模的时间事件方法比较了 RAM 的判别性能和校准。
在 1478 例患者中，90 天 VTE 的累积发生率为 1.6%。改进和日内瓦 RAM 的区分度相似，30 天 AUC（曲线下面积）分别为 0.78（95%置信区间：0.65-0.92）和 0.81（0.73-0.89）。根据改进的 RAM，68%的参与者处于低危状态（90 天内 VTE 发生率为 0.8%），32%处于高危状态（VTE 发生率为 4.7%），敏感性为 73%。根据日内瓦 RAM，35%的参与者处于低危状态（VTE 发生率为 0.6%），65%的参与者处于高危状态（VTE 发生率为 2.8%），敏感性为 90%。在未接受血栓预防的患者中，日内瓦 RAM 的敏感性（85%）略高于改进 RAM（54%）。我们得出了一个简化的日内瓦 RAM，其具有与原始日内瓦 RAM 相当的判别力和校准。
我们发现改进和日内瓦 RAM 的判别能力相当。改进的 RAM 将更多的患者归类为低危，但敏感性可能较低，VTE 风险较高，这表明应使用较低的低危阈值（<2）。简化的日内瓦 RAM 可能是具有增强可用性的日内瓦 RAM 的替代方案。
