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Abstract: Introduction: Increased cardiovascular mortality and risk of venous thromboembolism are serious extra-pulmonary complications of chronic obstructive pulmonary disease (COPD). Previously, circulating active tissue factor (TF) and factor XIa (FXIa) have been reported to be associated with acute coronary syndromes. Objective: To measure plasma FXIa and active TF, prothrombin fragment 1.2 (F1.2), and markers of systemic inflammation (C-reactive protein [CRP], interleukin-6 [IL-6], tumor necrosis factor α [TNFα] and matrix metalloproteinase 9 [MMP-9]) in 60 patients with documented stable COPD free of previous thromboembolic events. Methods: In-house clotting assays using inhibitory monoclonal antibodies against FXIa and TF. Results: FXIa was detected in 9 (15%) and TF activity in 7 (11.7%) COPD patients. Subjects positive for FXIa and/or TF (n=10; 16.7%) had higher F1.2 (median [interquartile range], 398 [216] vs 192 [42] pM, p<0.000001), fibrinogen (5.58 [2.01] vs 3.97 [2.47] g/L, p=0.0007), CRP (14.75 [1.20] vs 1.88 [2.95] mg/L, p<0.000001), IL-6 (8.14 [4.74] vs 2.45 [2.24] pg/mL, p=0.00002), and right ventricular systolic pressure (47 [15] vs 38 [12] mmHg, p=0.023), and lower vital capacity (66 [15] vs 80 [17] % predicted, p=0.04) than COPD patients without detectable FXIa and TF. COPD severity was not associated with the presence of circulating FXIa and active TF. Conclusions: This is the first study to show that active FXIa and TF are present in stable COPD patients, who exhibit enhanced systemic inflammation and thrombin generation. Our findings suggest a new prothrombotic mechanism which might contribute to elevated risk of thromboembolic complications in COPD. [Copyright &y& Elsevier]

Abstract: Background: Chronic obstructive pulmonary disease (COPD) is associated with an increased risk for thromboembolic events. We investigated thrombin generation profiles in COPD patients and their dependence on plasma factor/inhibitor composition. Methods: Factors (f) (fII, fV, fVII, fVIII, fIX, fX), antithrombin, protein C (PC) and free tissue factor pathway inhibitor (fTFPI) from 60 COPD patients (aged 64.2±10.1years; a mean forced expiratory volume in 1 second [FEV1], 55.6±15.8% of predicted values) were compared with those for 43 controls matched for age, sex, weight and smoking. Patients receiving anticoagulation were excluded. Using each individual''s plasma coagulation protein composition, tissue factor-initiated thrombin generation was assessed computationally. Results: COPD patients had higher fII (115±16 vs 102±10%, p<0.0001), fV (114±19 vs 102±12%, p=0.0002), fVII (111±15 vs 102±17%, p=0.002), fVIII (170±34 vs 115±27%, p<0.0001), and fIX (119±21 vs 107±17%, p=0.003), and lower fTFPI (17.7±3.2 vs 18.9±3.2ng/ml, p=0.047) compared with controls, while fX, antithrombin, and PC were similar in both groups. Computational thrombin generation profiles showed that compared with controls, COPD patients had higher maximum thrombin levels (+28.3%, p<0.0001), rates of thrombin generation (+46.1%, p<0.0001) and total thrombin formation (+14.4%, p<0.001), together with shorter initiation phase of thrombin generation (p<0.0001) and the time to maximum thrombin levels (p<0.0001). Thrombin generation profiles in COPD patients can be normalized via correction of fII, fVIII , fIX and TFPI. The severity of COPD and inflammatory markers were not associated with thrombin generation profiles. Conclusions: Prothrombotic phenotype in COPD patients is largely driven by increased prothrombin, fVIII, fIX, and lower fTFPI. [Copyright &y& Elsevier]

Discusses the clinical management of antiphospholipid syndrome, a condition in which antibodies binding to phospholipids are thought to be involved in the development of thrombosis and/or pregnancy complications. Antigenic determinants of antiphospholipid antibodies; Anticoagulant mechanisms of lupus anticoagulants; Diagnosis; Treatment regimen.

Background: Development of clinical practice guidelines involves making trade-offs between desirable and undesirable consequences of alternative management strategies. Although the relative value of health states to patients should provide the basis for these trade-offs, few guidelines have systematically summarized the relevant evidence. We conducted a systematic review relating to values and preferences of patients considering antithrombotic therapy.Methods: We included studies examining patient preferences for alternative approaches to antithrombotic prophylaxis and studies that examined, in the context of antithrombotic prophylaxis or treatment, how patients value alternative health states and experiences with treatment. We conducted a systematic search and compiled structured summaries of the results. Steps in the process that involved judgment were conducted in duplicate.Results: We identified 48 eligible studies. Sixteen dealt with atrial fibrillation, five with VTE, four with stroke or myocardial infarction prophylaxis, six with thrombolysis in acute stroke or myocardial infarction, and 17 with burden of antithrombotic treatment.Conclusion: Patient values and preferences regarding thromboprophylaxis treatment appear to be highly variable. Participant responses may depend on their prior experience with the treatments or health outcomes considered as well as on the methods used for preference elicitation. It should be standard for clinical practice guidelines to conduct systematic reviews of patient values and preferences in the specific content area. [ABSTRACT FROM AUTHOR]