The RANE Center for Venous and Lymphatic Diseases, Jackson, Miss.
The RANE Center for Venous and Lymphatic Diseases, Jackson, Miss.
J Vasc Surg Venous Lymphat Disord. 2021 Sep;9(5):1119-1127. doi: 10.1016/j.jvsv.2020.12.071. Epub 2020 Dec 16.
Thrombophilia conditions are associated with an increased risk of venous thromboembolism. Elevated plasma levels of factor VIII (>150 IU/dL) increase the risk of venous thrombosis. The aim of this report is to analyze a subset of patients in whom plasma factor VIII levels were investigated as part of a thrombophilia panel at a specialty venous clinic at a tertiary care hospital.
From January 2019 to December 2019, records of all patients (n = 306) who had a plasma factor VIII level assay performed as part of a thrombophilia panel were retrospectively analyzed. Group 1 (n = 92) had normal factor VIII levels (≤150 IU/dL), whereas group 2 (n = 214) had elevated factor VIII levels (>150 IU/dL). Venous thromboembolic events were classified as provoked if there was an association with surgery, trauma, immobilization, orthopedic fracture, peripartum period, or use of hormones. If there was no associated factor identifiable in the patient's history, the event was considered unprovoked.
The median age for patients in groups 1 and 2 was 55 and 65 years, respectively. Family history of deep venous thrombosis (DVT) was noted in 6 patients in group 1 (6.5%) vs 77 patients in group 2 (36%), P value: .0001. Unprovoked DVT was more commonly noted in group 2 patients (66%) compared with group 1 patients (5%), P value: .0001. In addition, venous ulceration was more commonly encountered in group 2 (23%) than group 1 (11%), P value: .008. Factor VIII level >150 IU/dL was a significant predictor of DVT occurrence itself (odds ratio: 3.3, P value <.005). Factor VIII level >200 IU/dL was a significant predictor of occurrence of two or more episodes of DVT (odds ratio: 12.3, P value < .005).
Factor VIII levels were found to be elevated in a significant proportion of patients in whom thrombophilia testing was performed at a specialty venous clinic. This elevation was more common in patients with venous ulceration, a positive family history of DVT, and a personal history of an unprovoked DVT. Levels above 200 IU/dL were associated with DVT recurrence. This has important implications for secondary prophylactic strategies for DVT.
血栓形成倾向与静脉血栓栓塞风险增加相关。血浆因子 VIII 水平升高（>150IU/dL）会增加静脉血栓形成的风险。本报告的目的是分析在一家三级医院的专科静脉诊所进行血栓形成倾向检测时，部分患者的血浆因子 VIII 水平。
2019 年 1 月至 2019 年 12 月，回顾性分析了所有接受血浆因子 VIII 水平检测的患者（n=306）的记录，这些患者是作为专科静脉诊所血栓形成倾向检测的一部分。第 1 组（n=92）因子 VIII 水平正常（≤150IU/dL），第 2 组（n=214）因子 VIII 水平升高（>150IU/dL）。如果静脉血栓栓塞事件与手术、外伤、固定、骨科骨折、围产期或激素使用有关，则将其归类为诱因。如果在患者病史中无法识别相关因素，则认为该事件为非诱因。
第 1 组和第 2 组患者的中位年龄分别为 55 岁和 65 岁。第 1 组 6 例（6.5%）患者有深静脉血栓形成（DVT）家族史，第 2 组 77 例（36%）患者有该家族史，P 值：<.0001。第 2 组患者（66%）更常见非诱因性 DVT，而第 1 组患者（5%）则较少见，P 值：<.0001。此外，第 2 组（23%）比第 1 组（11%）更常发生静脉溃疡，P 值：.008。因子 VIII 水平>150IU/dL 是 DVT 发生本身的显著预测因子（比值比：3.3，P 值<.005）。因子 VIII 水平>200IU/dL 是发生两次或更多次 DVT 的显著预测因子（比值比：12.3，P 值<.005）。
在专科静脉诊所进行血栓形成倾向检测的患者中，发现相当一部分患者的因子 VIII 水平升高。在有静脉溃疡、DVT 阳性家族史和非诱因性 DVT 个人史的患者中，这种升高更为常见。水平高于 200IU/dL 与 DVT 复发有关。这对 DVT 的二级预防策略有重要意义。
