Transfer RNAs are linked to ischemic stroke and major bleeding in patients with end-stage kidney disease.

BACKGROUND: Patients with end-stage kidney disease (ESKD) are at very high risk for thromboembolism and bleeding. This study aimed to identify small non-coding RNAs (sncRNAs), specifically microRNAs and transfer-RNA (tRNA)-derived fragments (tRFs), as potential novel biomarkers for predicting thromboembolism and bleeding in this high-risk population. METHODS: In this sncRNA discovery research, we leveraged the VIVALDI cohort, consisting of 625 ESKD patients on hemodialysis, to conduct two nested case-control studies, each comprising 18 participants. The primary outcomes were ischemic stroke in the first study and major bleeding in the second. Plasma samples were processed using the miND pipeline for RNA-seq analysis to investigate differential expression of microRNAs and tRNA/tRFs between cases and their respective matched controls, with results stringently adjusted for false discovery rate (FDR). RESULTS: No significant differential expression of microRNAs for either ischemic stroke or major bleeding outcomes was observed in the two nested case-control studies. However, we identified four tRNAs significantly differentially expressed in ischemic stroke cases and seven in major bleeding cases, compared to controls (FDR<0.1). Coverage plots indicated that specific tRNA fragments (tRFs), rather than full-length tRNAs, were detected, however. Alternative mapping approaches revealed challenges and technical limitations that precluded in-depth differential expression analyses on these specific tRFs. Yet, they also underscored the potential of tRNAs and tRFs as markers for thromboembolism and bleeding. CONCLUSION: While microRNAs did not show significant differential expression, our study identifies specific tRNAs/tRFs as potential novel biomarkers for ischemic stroke and major bleeding in ESKD patients. .

Plasmin Generation Analysis in Patients with Bleeding Disorder of Unknown Cause.

Bleeding disorder of unknown cause (BDUC) is a diagnosis of exclusion after evaluation of plasma coagulation and platelet function. The underlying mechanisms are unclear, but increased fibrinolysis and abnormal clot formation may play a role. All BDUC patients (n=375) from the Vienna bleeding biobank were analyzed in comparison to healthy controls (HC, n=100) in this case-control study. Plasmin generation (PG) parameters were analyzed using calibrated fluorescence detection in citrated-plasma samples. Turbidimetric plasma clot formation/ lysis of 293 (78%) BDUC patients and confocal microscopy of clots from representative BDUC patients (n=6) and HC (n=9) were assessed. Fibrinolytic factors were measured using commercially available ELISAs. In PG analysis, BDUC patients exhibited lower velocity and peak plasmin, but a higher endogenous plasmin potential compared to HC. Peak plasmin correlated with maximum clot absorbance, but not with clot lysis time. Clot absorbance is an indicator of clot fiber density. Confocal microscopy analysis revealed that BDUC patients' clots had a tendency towards thicker fibers, which negatively correlated with peak plasmin (r=-0.561, p=0.030). Peak plasmin correlated weakly with FXIII, but not with the other fibrinolytic factors (alpha2-antiplasmin, thrombin activatable fibrinolysis inhibitor or plasminogen activator inhibitor 1) or bleeding severity. A model comprising fibrinogen and parameters of PG yielded high predictive power in discriminating BDUC patients from HC during 5-fold stratified cross validation (80% of data, mean AUC: 0.847). The same model generalized well to unseen data (20% of data, AUC: 0.856). Overall, BDUC patients exhibited counterintuitively reduced peak plasmin, potentially related to altered clot structure.

Telomere length is associated with increased risk of cardiovascular events in patients with end-stage kidney disease on hemodialysis.

INTRODUCTION: Patients with chronic kidney disease (CKD), especially those with end-stage kidney disease (ESKD) on hemodialysis (HD), are at increased risk for cardiovascular disease (CVD), including myocardial infarction and ischemic stroke. A shortening in telomere length, as a parameter for accelerated vascular aging, is an established biomarker for CVD in the general population. We aimed to elucidate the role of telomere length in ESKD patient on HD and its association with cardiovascular outcomes. METHODS: Telomere length was measured in a prospective population-based cohort study of prevalent HD patients. DNA was isolated from whole blood, sampled at baseline, and analyzed for telomere length via a qPCR-based approach. The risk for the occurrence of the independently adjudicated 3P-MACE outcome (myocardial infarction, ischemic stroke, and cardiovascular death) was statistically analyzed considering the competing risk of non-cardiovascular death. RESULTS: In the cohort of 308 patients with ESKD (115 (37.3%) women, median (25th-75th percentile) age: 67.0 (56.8 - 76.0), the median telomere length was 1.51 kb (25th-75th percentile 0.6-3.2 kb). The 3P-MACE outcome occurred with an incidence rate of 9.4 per 100 patient-years. Patients with longer telomere length more frequently had vascular nephropathy compared to patients with shorter telomere length. Interestingly, patients in the highest quartile of telomere length had a 1.8-fold increased risk for 3P-MACE (95%CI 1.051-3.201, p=0.033), after multivariable adjustment for age, history of stroke, myocardial infarction, venous thromboembolism, presence of heart valve replacement, atrial fibrillation, smoking, anticoagulation, or immunosuppressive use. CONCLUSION: Surprisingly, in this high-risk cohort of patients with ESKD on HD, longer telomere lengths were associated with increased risk of cardiovascular events.

Biomarker-enhanced cardiovascular risk prediction in patients with cancer: a prospective cohort study.

BACKGROUND: Continuously improving cancer-specific survival puts a growing proportion of cancer patients at risk of major adverse cardiovascular events (MACE), but tailored tools for cardiovascular risk prediction remain unavailable. OBJECTIVES: To assess a broad panel of cardiovascular biomarkers and risk factors for the prediction of MACE and cardiovascular death in cancer patients. METHODS: In total, 2192 patients with newly diagnosed or recurrent cancer were followed prospectively for the occurrence of 2-year MACE and 5-year cardiovascular death. Univariable and multivariable risk models were fit to assess independent associations of cardiovascular risk factors and biomarkers with adverse outcomes, and a risk score was developed. RESULTS: Traditional cardiovascular risk factors and selected cancer types were linked to higher MACE risk. While levels of Lp(a), CRP, and GDF-15 did not associate with MACE, levels of ICAM-1, P-/E-/L-selectins, and NT-proBNP were independently linked to 2-year MACE risk. A clinical risk score was derived, assigning +1 point for male sex, smoking, and age of ≥60 years and +2 points for atherosclerotic disease, yielding a bootstrapped C-statistic of 0.76 (95% CI: 0.71-0.81) for the prediction of 2-year MACE. Implementation of biomarker data conferred improved performance (0.83, 95% CI: 0.78-0.88), with a simplified model showing similar performance (0.80, 95% CI: 0.74-0.86). The biomarker-enhanced and simplified prediction models achieved a C-statistic of 0.82 (95% CI: 0.71-0.93) and 0.74 (95% CI: 0.64-0.83) for the prediction of 5-year cardiovascular death. CONCLUSION: Biomarker-enhanced risk prediction strategies allow the identification of cancer patients at high risk of MACE and cardiovascular death. While external validation studies are ongoing, this first-of-its-kind risk score may provide the basis for personalized cardiovascular risk assessment across cancer entities.

Bleeding events in patients with cancer: incidence, risk factors, and impact on prognosis in a prospective cohort study.

Hemostatic imbalances are frequent in patients with cancer. While cancer-associated thrombotic complications have been well characterized, data on bleeding events in cancer patients are sparse. Therefore, we aimed to investigate the incidence, risk factors, and impact on prognosis of bleeding events in cancer patients initiating systemic anti-cancer therapies in a prospective cohort study, the Vienna Cancer, Thrombosis and Bleeding Study (CAT-BLED). The primary study outcome was defined as clinically relevant bleeding (CRB), comprising major bleeding (MB) and clinically relevant non-major bleeding (CRNMB). In total, 791 patients (48% female, median age [interquartile range, IQR]: 63 [54-70] years) with various cancer types, 65.5% stage IV, were included. Over a median follow-up of 19 months (IQR: 8.7-24.0), we observed 194 CRB events in 139 (17.6%) patients, of which 42 (30%) were tumor-related, 64 (46.0%) gastrointestinal, and 7 (5.0%) intracerebral. The 12-month cumulative incidence of first CRB and MB was 16.6% (95% confidence interval [CI]: 13.7-19.6) and 9.1% (95% CI: 6.8-11.3) in the whole cohort and 14.4% (95% confidence interval [CI]: 11.2-17.5) and 7.0% (95% CI: 4.7-9.2) in those without anticoagulation. Patients with head and neck cancer had the highest risk of CRB. Lower baseline hemoglobin and albumin were associated with bleeding in patients without anticoagulation. Seven (5.0%) bleeding events were fatal, of which 6 occurred in patients without anticoagulation. Patients with CRB were at an increased risk of all-cause mortality (multivariable transition hazard ratio [95%CI]: 5.80 [4.53-7.43]). In patients with cancer bleeding events represent a frequent complication and are associated with increased mortality.

Fibrinolysis is impaired in patients with primary immune thrombocytopenia.

BACKGROUND: Patients with primary immune thrombocytopenia (ITP) have an increased risk of thrombosis, which may be due to altered fibrinolysis. OBJECTIVES: To elucidate the clinical impact of delayed fibrinolysis in ITP patients. METHODS: A turbidimetric clot formation and lysis assay and a fluorometric plasmin generation (PG) assay were performed and levels of plasminogen-activator-inhibitor-1 (PAI-1), tissue-plasminogen-activator (tPA), tPA-PAI-1 complexes, α2-antiplasmin, TAFI and D-Dimer were assessed in 86 adult primary ITP patients and 78 healthy controls (HC). RESULTS: ITP patients showed significantly delayed clot formation, increased clot density, and prolonged clot lysis time (CLT) compared to HC with a median (IQR) CLT of 28.0 (13.7-34.7) minutes in patients and 17.3 (12.0-28.0) minutes in HC, while in PG only the lag time was prolonged. In ITP patients compared to controls, PAI-1 was higher (1.2 (0.8-2.6) vs 1.1 (0.6-2.1) U/mL), and tPA antigen and activity were lower (tPA antigen: 2.6 (1.1-4.4) vs 3.7 (3.2-4.7) ng/mL; tPA activity ≤0 U/mL: 26% vs 7%). TPA-PAI-1 complex levels were positively associated with CLT in multiple linear regression analysis (ß=0.241, p=0.019), whereas PG parameters were not associated with CLT. Six patients, who developed thrombosis during follow-up, had higher levels of tPA-PAI-1 complexes. CONCLUSION: Prolonged CLT and delayed onset of PG may indicate a hypofibrinolytic tendency in ITP patients, as also indicated by high PAI-1 and low tPA levels. No association was found between fibrinolytic potential and the bleeding phenotype, whereas higher tPA-PAI-1 complex levels were associated with prolonged CLT and increased in patients with future thrombosis.

Anxiety in patients with venous thromboembolism: quantification and risk factors in a prospective cohort study.

BACKGROUND: Patients with venous thromboembolism (VTE) are at risk of psychological consequences. However, as opposed to physical sequelae of VTE, mental health issues are understudied. OBJECTIVES: To assess anxiety after VTE and investigate associated clinical characteristics. METHODS: We conducted a prospective cohort study, including patients with acute deep vein thrombosis (DVT) and/or pulmonary embolism. Patients with cancer, pregnancy, or puerperium were excluded. Anxiety was assessed with the Patient-Reported Outcome Measurement Information System short form 8a. Standardized T-scores were calculated (reference, 50; SD, 10), with higher values indicating more anxiety. We associated clinical characteristics at baseline with T-scores at 3-month follow-up in a multivariable linear regression model. Patient clusters depending on anxiety trajectories were explored. RESULTS: We included 257 patients (38.5% women) with a median (IQR) age of 54.1 (42.2-63.5) years. While mean (SD) T-scores decreased from baseline to follow-up (51.03 [9.18] to 46.74 [8.89]; P < .001), we observed an increase in 23.7% of all patients. Female sex (T-score change, 3.09; 95% CI, 0.96-5.22), older age until 45 years, and anxiety at baseline were associated with increased T-scores at follow-up. VTE history (-1.55; 95% CI, -3.62 to 0.52) and pulmonary embolism (-1.23; 95% CI, -3.16 to 0.69) were associated with reduced T-scores, albeit not reaching statistical significance. In a cluster of older female patients with DVT, anxiety tended to increase over time. CONCLUSION: While most patients with VTE reported reduced anxiety over time, some patients experienced worsening. Female sex, older age, more anxiety at baseline, no VTE history, and DVT were associated with increased anxiety 3 months after VTE.

Prevalence and incidence of venous thromboembolism in geriatric patients admitted to long-term care hospitals.

The risk of venous thromboembolism (VTE) increases with age. However, the risk of VTE in the setting of long-term care hospitals is understudied. Our objective was to provide data on the prevalence and incidence of VTE in older adults admitted to long-term care hospitals. In this retrospective cohort study, we collected data about chronically ill and multimorbid patients aged 65 years and older from two long-term care hospitals. The primary endpoint of this study was the lifetime prevalence of VTE, and the secondary endpoint was VTE incidence during residency in long-term care hospitals. We analysed data from 1148 patients with a mean age of 84.1 ± 7.9 years, of whom 74.2% were women. The lifetime prevalence of VTE at baseline was 9.6% (95% CI 7.9-11.4). Cumulative incidence of VTE at 1, 2, and 3 years from baseline was estimated at 3.5% (95% CI 2.5-4.7), 4.2% (95% CI 3.1-5.5), and 5.4% (95% CI 4.1-7.0), respectively. Overall, the incidence rate of VTE in our study was 2.82 (95% CI 2.18-3.66) per 100 person-years. The study indicated a considerably high lifetime prevalence and incidence of VTE during residence in long-term care hospital settings, requiring further evaluation in larger prospective studies.

Predelivery Haemostatic Biomarkers in Women with Non-Severe Postpartum Haemorrhage.

Background: Postpartum haemorrhage (PPH) is a frequent complication of childbirth that is difficult to predict. Predelivery coagulation biomarkers may help to guide preventive strategies. Our objective was to evaluate the association of predelivery haemostatic biomarkers with non-severe PPH. Methods: A nested case-control study was conducted within the « Study of Biological Determinants of Bleeding Postpartum ¼ in order to compare different haemostatic biomarkers in plasma from pregnant women with non-severe PPH (cases) and controls without PPH matched for age, body mass index, term, and mode of delivery. Blood was collected at entry in the delivery room. Global haemostatic assays (thrombin generation assay (TGA) and plasmin generation assay (PGA)) were then performed on freshly thawed aliquots of platelet-poor plasma. Results: A total of 370 pregnant women (185 cases and 185 controls) were included. Median [interquartile range] predelivery platelet count was lower in PPH cases than in controls (217 [181-259] versus 242 [196-280] G/L). TGA and PGA parameters were similar between cases and controls. In a subset analysis of vaginal deliveries (n = 144), median predelivery TGA thrombin peak was lower, and median predelivery PGA lag phase was longer in cases compared to controls. In multivariable analysis, only predelivery platelet count was independently associated with non-severe PPH. Conclusions: Predelivery platelet count is associated with non-severe PPH. Differences in other haemostatic parameters are tenuous, questioning their usefulness in predicting non-severe PPH.

Functional limitations 3 and 12 months after venous thromboembolism: a cohort study.

Background: Venous thromboembolism (VTE) is associated with various long-term complications. Objectives: We aimed to investigate the association of clinical characteristics at VTE diagnosis with functional limitations 3 and 12 months afterward. Methods: We conducted a prospective cohort study of VTE patients, excluding patients with cancer, pregnancy, and postpartum period. Functional limitations were assessed with the post-VTE functional status (PVFS) scale (range, 0-4) within 21 days of diagnosis, after 3 and 12 months (prospectively), and 1 month before diagnosis (retrospectively). Twelve-month follow-up was only performed in patients on anticoagulation. We fitted 2 proportional odds logistic regression models for the 3- and 12-month follow-ups and computed odds ratios (ORs) with 95% bootstrap percentile confidence intervals (CIs). Results: We included 307 patients (42% female, median age 55.6 years) with a median (IQR) PVFS scale grade of 2 (2-3) at study inclusion and 0 (0-0) before diagnosis. After 3 months, PVFS scale grade in 269 patients was 1 (0-2). Female sex (OR, 2.15; 95% CI, 1.26-4.14), body mass index (OR per 1 kg/m2 increase, 1.05; 95% CI, 1.00-1.10), functional limitations at baseline, and older age were associated with functional limitations. After 12 months, PVFS scale grade in 124 patients was 1 (0-2). Female sex (OR, 4.47; 95% CI, 2.11-16.00), history of cardiovascular/pulmonary disease (OR, 2.36; 95% CI, 1.01-6.89), and functional limitations at baseline were associated with functional limitations. Conclusion: Functional limitations in VTE patients improved 3 and 12 months after diagnosis but did not return to pre-VTE values. We identified clinical characteristics that could help identify patients at risk of persisting functional limitations after VTE.

[Treatment of haemophilia in Austria]. / Hämophilie-Behandlung in Österreich.

This guideline is intended to provide practical guidance for the diagnosis and treatment of haemophilia in Austria. Few randomized controlled interventional trials are available addressing the treatment of haemophilia, therefore recommendations are usually based on low level of evidence and represent expert consensus.This guideline is based on the WFH guideline, published in 2020, and adapted according to the national circumstances and experience.It includes recommendations and suggestions for diagnosis and follow-up visits and pharmacological therapies for treatment and prophylaxis. Further topics comprise special aspects in children and adults with severe haemophilia, outcome measurement, and management of trauma, special bleedings and interventions, including dental procedures, inhibitors, management of haemophilia carriers, and psychosocial aspects.

A 360-degree perspective on adeno-associated virus (AAV)-based gene therapy for haemophilia: Insights from the physician, the nurse and the patient.

BACKGROUND: Adeno-associated virus (AAV)-based gene therapy for haemophilia has advanced substantially in the last 13 years; recently, three products have received approvals from regulatory authorities. Although the impact on quality of life seems promising, some limitations remain, such as the presence of pre-existing anti-AAV neutralising antibodies and the occurrence of hepatotoxicity. This review follows the CSL Behring-sponsored symposium at the 27th Congress of the European Hematology Association (EHA) 2022 that examined the haemophilia gene therapy process from a 360-degree multidisciplinary perspective. Here, the faculty (haematologist, nurse and haemophilia patient) summarised their own viewpoints from the symposium, with the aim of highlighting the key considerations required to engage with gene therapy effectively, for both patients and providers, as well as the importance of multidisciplinary collaboration, including with industry. RESULTS: When considering these new therapies, patients face a complex decision-making process, which includes whether gene therapy is right for them at their current stage of life. The authors agreed that collaboration and tailored education across the multidisciplinary team (including patients and their carers/families), starting early in the process and continuing throughout the long-term follow-up period, is key for the success of gene therapy. Additionally, patient expectations, which may surround eligibility, follow-up requirements and treatment outcomes, should be continually explored. During these ongoing discussions, transparent communication of the unknown factors, such as anticipated clotting factor levels, long-term factor expression and safety, and psychological changes, is critical. To ensure efficiency and comprehensiveness, clearly­defined protocols should outline the whole process, which should include the recording and management of long-term effects. CONCLUSION: In order to engage effectively, both patients and providers should be familiar with these key considerations prior to their involvement with the haemophilia gene therapy process. The future after the approval of haemophilia gene therapies remains to be seen and real-world evidence is eagerly awaited.

The plasma miRNome and venous thromboembolism in high-grade glioma: miRNA Sequencing of a nested case-control cohort.

Patients with high-grade gliomas are at high risk of venous thromboembolism (VTE). MicroRNAs (miRNAs) are small non-coding RNAs with multiple roles in tumour biology, haemostasis and platelet function. Their association with VTE risk in high-grade glioma has not been comprehensively mapped so far. We thus conducted a nested case-control study within 152 patients with WHO grade IV glioma that had been part of a prospective cohort study on VTE risk factors. At inclusion a single blood draw was taken, and patients were thereafter followed for a maximum of 2 years. During that time, 24 patients (16%) developed VTE. Of the other 128 patients, we randomly selected 24 age- and sex-matched controls. After quality control, the final group size was 21 patients with VTE during follow-up and 23 without VTE. Small RNA next-generation sequencing of plasma was performed. We observed that hsa-miR-451a was globally the most abundant miRNA. Notably, 51% of all miRNAs showed a correlation with platelet count. The analysis of miRNAs differentially regulated in VTE patients-with and without platelet adjustment-identified potential VTE biomarker candidates such as has-miR-221-3p. Therewith, we here provide one of the largest and deepest peripheral blood miRNA datasets of high-grade glioma patients so far, in which we identified first VTE biomarker candidates that can serve as the starting point for future research.

Standardization of definition and management for bleeding disorder of unknown cause: communication from the SSC of the ISTH.

In many patients referred with significant bleeding phenotype, laboratory testing fails to define any hemostatic abnormalities. Clinical practice with respect to diagnosis and management of this patient cohort poses significant clinical challenges. We recommend that bleeding history in these patients should be objectively assessed using the International Society on Thrombosis and Haemostasis (ISTH) bleeding assessment tool. Patients with increased bleeding assessment tool scores should progress to hemostasis laboratory testing. To diagnose bleeding disorder of unknown cause (BDUC), normal complete blood count, prothrombin time, activated partial thromboplastin time, thrombin time, von Willebrand factor antigen, von Willebrand factor function, coagulation factors VIII, IX, and XI, and platelet light transmission aggregometry should be the minimum laboratory assessment. In some laboratories, additional specialized hemostasis testing may be performed to identify other rare causes of bleeding. We recommend that patients with a significant bleeding phenotype but normal laboratory investigations should be registered with a diagnosis of BDUC in preference to other terminology. Global hemostatic tests and markers of fibrinolysis demonstrate variable abnormalities, and their clinical significance remains uncertain. Targeted genomic sequencing examining candidate hemostatic genes has a low diagnostic yield. Underlying BDUC should be considered in patients with heavy menstrual bleeding since delays in diagnosis often extend to many years and negatively impact quality of life. Treatment options for BDUC patients include tranexamic acid, desmopressin, and platelet transfusions.

Mucin 1 and venous thrombosis in tumor-bearing mice and patients with cancer.

INTRODUCTION: Mucins released from epithelial tumors have been proposed to play a role in cancer-associated thrombosis. Mucin1 (MUC1) is a transmembrane mucin that is overexpressed in a variety of human malignancies, including breast and pancreatic cancer. We analyzed the association of MUC1 and venous thrombosis in a mouse tumor model and in patients with cancer. MATERIALS AND METHODS: We used a human pancreatic cancer cell line HPAF-II that expresses a high level of MUC1. We grew HPAF-II tumors in the pancreas of Crl:NU-Foxn1nu male mice. MUC1 in plasma and extracellular vesicles (EVs) isolated from plasma was measured using an enzyme-linked immunosorbent assay. MUC1 in EVs and venous thrombi from tumor-bearing mice was assessed by western blotting. We measured MUC1 in plasma from healthy controls and patients with stomach, colorectal or pancreatic cancer with or without venous thromboembolism. RESULTS AND DISCUSSION: MUC1 was detected in the plasma of mice bearing HPAF-II tumors and was associated with EVs. MUC1 was present in venous thrombi from mice bearing HFAP-II tumors. Recombinant MUC1 did not induce platelet aggregation. Levels of MUC1 were higher in patients with pancreatic cancer compared with healthy controls. In contrast to the mouse model, MUC1 was present in EV-free plasma in samples from healthy controls and patients with cancer. There was no significant difference in the levels of MUC1 in cancer patients with or without VTE. Our data did not find any evidence that MUC1 contributed to VTE in patients with cancer.

Impact of thrombosis location on walking capacity: a cohort study of patients with acute deep vein thrombosis.

Background: Data on walking impairment during the acute phase of deep vein thrombosis (DVT) are limited. Objectives: This study aimed to assess the degree of walking impairment in patients with acute DVT, with a particular focus on the relation to the DVT's anatomical location. Methods: Patients with sonographically confirmed DVT were eligible for inclusion in this cohort study. Pain-free walking distance (PWD) and maximum walking distance (MWD) were determined using standardized treadmill ergometer tests and analyzed in relation to DVT location. The impact of previous DVT on walking capacity was evaluated in an exploratory analysis. Results: The study included 64 patients (31% women; median age, 55 years). The median (IQR) time from diagnosis to exercise test was 3 (1-5) days. Patients with suprainguinal DVT demonstrated significantly shorter median (IQR) MWD than those with infrainguinal DVT (130 (61-202) m vs 565 (128-750) m; P < .01), while PWD did not significantly differ (PWD: 20 (0-30) m vs 40 (0-222) m; P = .14). The proportion of patients who had to terminate treadmill tests prematurely was higher in patients with suprainguinal DVT (91.7% vs 57.7%; P = .04). PWD and MWD seemed to be similar in patients with and without a history of DVT. Premature test termination and suprainguinal DVT location were associated with reduced quality of life, as measured by the EuroQoL Group 5-Dimension 5-Level questionnaire and visual analog scale. Conclusion: Suprainguinal DVT was linked to a more pronounced walking impairment compared with infrainguinal DVT. Limited walking capacity was associated with a reduced quality of life.

Activated protein C and free protein S in patients with mild to moderate bleeding disorders.

BACKGROUND: Underlying mechanisms for bleeding and impaired thrombin generation (TG) and plasma clot formation (PCF) in patients with mild to moderate bleeding disorders (MBDs) are still to be elucidated, especially in bleeding disorder of unknown cause (BDUC). The role of the natural anticoagulants activated protein C (APC) and free protein S (PS) has not yet been investigated in this patient population. AIMS: To analyze antigen levels of APC and PS in patients with MBDs and BDUC and investigate associations to clinical bleeding phenotype and severity as well as and hemostatic capacity. METHODS: Antigen levels of APC and free PS were measured in 262 patients from the Vienna Bleeding Biobank (VIBB), a single-center cohort study, by ELISA and compared to 61 healthy controls (HC). RESULTS: Antigen levels of APC were higher in MBD patients than in HC when adjusted for age, sex and BMI (median (IQR) 33.1 (20.6-52.6) and 28.6 (16.4-47.2) ng/mL). This was most pronounced in patients with BDUC (35.3 (21.7-54.3) ng/mL). No differences in PS antigen levels between patients and HC were seen overall, or according to specific diagnoses. Further, no association between APC or PS and bleeding severity or global tests of hemostasis or TG were identified, while paradoxically APC weakly correlated with shorter lag time and time to peak of PCF in BDUC. CONCLUSION: Our data demonstrate increased antigen levels of APC in BDUC, which might contribute to the bleeding tendency in some patients and could be a future therapeutic target in BDUC.