Available evidence to identify factors independently associated with failed thromboprophylaxis (FT) in medical patients is insufficient. The present study seeks to evaluate in hospitalized patients, which clinical factors are associated with the development of FT. A case-control study nested to a historical cohort, comparing patients who developed failed thromboprophylaxis (cases) with those who did not (controls). Univariate and multivariate regression analysis was performed to define the factors associated with FT. We selected 204 cases and 408 controls (52.4% men, median age 63 years). Medical patients were 78.4%. The most frequent thromboprophylaxis scheme was enoxaparin. In the failed thromboprophylaxis group, most of the embolic events corresponded to pulmonary embolism (53.4%). Among cases, BMI was higher (26.3 vs. 25 kg/m2, p < 0.001), as was the proportion of patients with leukocytosis > 13,000 (27% vs. 18.9%, p:0.22), and patients who required intensive care management (48% vs. 24.8%, p < 0.001). Factors independently associated with FT were BMI (OR1.04;95%CI 1.00-1.09, p:0.39), active cancer (OR:1.63;95%IC 1.03–2.57, p:0.04), leukocytosis (OR:1.64;95%CI 1.05–2.57, p:0.03) and ICU requirement (OR:3.67;95%CI 2.31–5.83, p < 0.001). Our study suggests that the failed thromboprophylaxis is associated with high BMI, active cancer, leukocytosis, and ICU requirement. Future studies should evaluate whether there is benefit in adjusting the thromboprophylaxis scheme in patients with one or more of these factors.

中文翻译：

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血栓预防失败导致静脉血栓栓塞性疾病的相关因素

现有证据不足以确定与内科患者血栓预防（FT）失败独立相关的因素。本研究旨在评估住院患者中哪些临床因素与 FT 的发生相关。一项病例对照研究嵌套在一个历史队列中，将血栓预防失败的患者（病例）与没有血栓预防的患者（对照）进行比较。进行单变量和多变量回归分析来定义与 FT 相关的因素。我们选择了 204 例病例和 408 例对照（52.4% 为男性，中位年龄 63 岁）。内科患者占78.4%。最常见的血栓预防方案是依诺肝素。在血栓预防失败组中，大多数栓塞事件对应于肺栓塞（53.4%）。在病例中，BMI较高（26.3 vs. 25 kg/m2，p < 0.001），白细胞增多> 13,000的患者比例较高（27% vs. 18.9%，p：0.22），以及需要重症监护管理的患者（48% 与 24.8%，p < 0.001）。与 FT 独立相关的因素为 BMI (OR1.04;95%CI 1.00-1.09, p:0.39)、活动性癌症 (OR:1.63;95%IC 1.03–2.57, p:0.04)、白细胞增多 (OR:1.64;95) %CI 1.05–2.57，p:0.03）和 ICU 要求（OR：3.67；95%CI 2.31–5.83，p < 0.001）。我们的研究表明，血栓预防失败与高 BMI、活动性癌症、白细胞增多和 ICU 需求相关。未来的研究应该评估对于具有一种或多种这些因素的患者调整血栓预防方案是否有益。