Incidence rate of venous thrombosis in women switching combined oral contraceptives: a cohort study.

Background: The incidence rate of venous thrombosis (VT) in women switching combined oral contraceptives (COCs) is unknown. Objectives: We hypothesize that women switching COCs may have a similar increased incidence rate of VT as women who start COCs. Switching means starting with a new COC, which may biologically approximate starting. Methods: We conducted a cohort study with data from the Netherlands and Denmark. First, we identified starters who were defined as women who did not use COCs in the 2 years prior to the start of their first COC prescription within the study period. Switchers were a subset of COC starters who redeemed a COC formulation different from their initial COC during follow-up but not longer than 12 months after starting. We estimated incidence rate ratios (adjusted incidence rate ratio [aIRR]) of VT with 95% CIs among COC switchers as compared with COC starters using Poisson regression adjusted for age, COC progestogen generation, and preexisting obesity. Results: In both countries, we found an increased risk of VT among switchers as compared with starters during the first 3 months of the follow-up (aIRR = 1.77; 95% CI, 1.22-2.56 in the Netherlands and aIRR = 1.50; 95% CI, 1.04-2.16 in Denmark). Conclusion: Switchers, particularly in the first 3 months after switching, may experience a renewed starter effect thereby increasing the risk of VT.

Hormonal contraceptive use after a first venous thrombotic event and the risk of recurrence in premenopausal women.

BACKGROUND: Extensive evidence is available on hormonal contraceptive (HC) use and the risk of a first venous thromboembolism (VTE) event. Despite recommendations to discontinue combined HC (CHC) use, some women continue or start its use after a first VTE. OBJECTIVES: We aimed to evaluate the VTE recurrence risk associated with HC use in premenopausal women. METHODS: Premenopausal women with a first VTE included in the Multiple Environmental and Genetic Assessment of Venous Thrombosis study between 1999 and 2004 were followed for a recurrence until 2010. Data on HC use were available through linkage to the Dutch Foundation for Pharmaceutical Statistics. The risk of recurrence was assessed 1) during anticoagulant therapy and 2) after cessation of anticoagulant therapy. Time-dependent Cox proportional hazards models were used to estimate hazard ratios (HRs) with 95% CIs adjusted for age and body mass index at baseline and thromboprophylaxis use during follow-up. RESULTS: Six hundred fifty women were uniquely linked and followed for a total of 3538 person-years (median, 6.1 years), during which 57 VTE recurrences occurred. Five occurred (8.8%) during anticoagulation treatment, with no clear risk difference for CHC use vs nonuse (HR, 0.8; 95% CI, 0.1-8.2). After anticoagulation cessation, CHC use was associated with a 2.4-fold higher risk of recurrence (HR, 2.4; 95% CI, 1.2-5.0) compared with nonuse. Recurrence risk for levonorgestrel-releasing intrauterine device use was similar to that for nonuse (HR, 0.9; 95% CI, 0.3-3.1). CONCLUSION: CHC use after a first VTE is safe during anticoagulant use but substantially increases the risk of a recurrent VTE event in absence of anticoagulant use. This study adds to the evidence regarding the use of a levonorgestrel-releasing intrauterine device as a safe alternative.

Association between venous thromboembolism-associated genetic variants, coagulation factor levels, and thrombin generation potential.

Recently three large meta-analyses of genome-wide association studies for venous thromboembolism (VTE) identified over 130 genetic variants. However, mechanisms by which newly identified and therefore underexplored VTE-associated genetic variants influence VTE remain unclear. To elucidate the mechanism, we investigated the association between 61 newly identified VTE-associated genetic variants and the levels of coagulation factor (F) VIII, FIX, FXI, and fibrinogen as well as thrombin generation parameters (lag time, peak, endogenous thrombin potential, time-to-peak, and velocity), which are well-known biological traits associated with VTE. This study was conducted on 5341 participants of the Netherlands Epidemiology of Obesity study. The associations between VTE-associated genetic variants and coagulation factor levels and thrombin generation parameters were examined using linear regression analyses, adjusted for age, sex, body mass index, oral contraceptive use, hormone replacement therapy, and menopausal status. Of 61 genetic variants, 33 were associated with one or more of the coagulation factor levels and thrombin generation parameters. Following multiple testing corrections, five genetic variants remained significant, of which MAP1A rs55707100 exhibited the most robust association with thrombin generation parameters and FXI levels (ß = -5.33%, 95% confidence interval: -8.44, -2.22). Our findings shed light on the underlying mechanisms by which these genetic variants influence the risk of VTE.

Genomic science of risk prediction for venous thromboembolic disease: convenient clarification or compounding complexity.

Venous thromboembolism (VTE) refers to abnormal blood clots in veins occurring in 1 to 2 per 1000 individuals every year. While anticoagulant treatment can prevent VTE, it increases the risk of bleeding. This emphasizes the importance of identifying individuals with a high risk of VTE and providing prophylactic interventions to these individuals to reduce both VTE and bleeding risks. Current risk assessment of VTE is based on the combination of mainly clinical risk factors. With the identification of an increasing number of genetic variants associated with the risk of VTE, the addition of genetic findings to clinical prediction models can improve risk prediction for VTE. Especially for individuals in high-risk situations, the added value of genetic findings to clinical prediction models may have benefits such as better prophylaxis of VTE and the reduced side effects of bleeding from unnecessary treatment. Nevertheless, the question of whether these models will eventually have clinical utility remains to be proven. Here, we review the current state of knowledge on genetic risk factors for VTE, explore genetic prediction models for VTE, and discuss their clinical implications and challenges.

Health-related quality of life after first venous thromboembolism in individuals aged 70 years and older.

Background: There is limited information on short- and long-term effects of venous thromboembolism (VTE) on health-related quality of life (HRQoL) in the elderly. Objectives: To assess change in generic HRQoL and disease-specific HRQoL in patients 1 year after the VTE. Methods: The Age and Thrombosis, Acquired and Genetic risk factors in the elderly (AT-AGE) study is a 2-center case-control study performed in Leiden, the Netherlands, and Vermont, United States, among individuals aged ≥70 years. We measured generic HRQoL using the 36-item Short Form Health Survey (SF-36) and disease-specific HRQoL using the Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms Questionnaire (VEINES-QoL/Sym) and the Pulmonary Embolism-Specific Quality of Life Questionnaire (PEmb-QoL). All patients completed these questionnaires shortly after their VTE and 1 year later, while controls completed the 36-item Short Form Health Survey questionnaire once. Linear regression for change in quality of life scores was performed and adjusted for potential confounders. Results: For the current analysis, we included patients who were visited twice (n = 316) and controls (n = 427) with HRQoL information. Mean age of patients and controls was similar (78.8 vs 75.5 years). In patients who survived at least 1 year after the VTE, generic HRQoL improved for both summary scores, but it did not reach the level of the age-matched controls: physical and mental summary scores increased by 5.6 and 5.5 points, respectively, but compared with controls, remained 8.2 and 6.4 points lower. For disease-specific HRQoL, the Pulmonary Embolism-Specific Quality of Life Questionnaire overall score decreased from 21.7% to 15.2%, indicating improved HRQoL. Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms Questionnaire scores did not change over time. Conclusion: Overall, the quality of life of patients with VTE was worse than that of controls after 1 year, indicating a long-term impact of VTE diagnosis in the elderly.

Sex-specific association between microvascular health and coagulation parameters: the Netherlands Epidemiology of Obesity study.

BACKGROUND: Microvascular dysfunction is a growing determinant of sex differences in coronary heart disease (CHD). Dysregulation of the coagulation system is involved in CHD pathogenesis and can be induced by endothelial glycocalyx (EG) perturbation. However, little is known about the link between EG function and coagulation parameters in population-based studies on sex specificity. OBJECTIVES: We sought to examine the sex differences in the relationship between EG function and coagulation parameters in a middle-aged Dutch population. METHODS: Using baseline measurements of 771 participants from the Netherlands Epidemiology of Obesity study (age, 56 years [IQR, 51-61 years]; 53% women; body mass index, 27.9 kg/m2 [IQR, 25.1-30.9 kg/m2]), associations between glycocalyx-related perfused boundary region (PBR) derived using sidestream dark-field imaging and coagulation parameters (factor [F]VIII/IX/XI; thrombin generation parameters; and fibrinogen) were investigated using linear regression analyses, adjusting for possible confounders (including C-reactive protein, leptin, and glycoprotein acetyls), followed by sex-stratified analyses. RESULTS: There was a sex difference in the associations between PBR and coagulation parameters. Particularly in women, 1-SD PBR (both total and feed vessel, indicating poorer glycocalyx status) was associated with higher FIX activity ([1.8%; 95% CI, 0.3%-3.3%] and [2.0%; 95% CI, 0.5%-3.4%], respectively) and plasma fibrinogen levels ([5.1 mg/dL; 95% CI, 0.4-9.9 mg/dL] and [5.8 mg/dL; 95% CI, 1.1-10.6 mg/dL], respectively). Furthermore, 1-SD PBRcapillary was associated with higher FVIII activity (3.5%; 95% CI, 0.4%-6.5%) and plasma fibrinogen levels (5.3 mg/dL; 95% CI, 0.6-10.0 mg/dL). CONCLUSION: We revealed a sex-specific association between microcirculatory health and procoagulant status, which suggests that microvascular health be considered during early development of CHD in women.

Plasma levels of coagulation factors VIII and IX and risk of venous thromboembolism: Systematic review and meta-analysis.

INTRODUCTION: The associations of plasma factor VIII (FVIII) and factor IX (FIX) levels with risk of venous thromboembolism (VTE) are not well defined. We performed a systematic review and meta-analysis of these associations. METHODS: Random effects inverse-variance weighted meta-analysis was used to estimate pooled odds ratios for comparisons across equal quartiles of the distributions and 90 % thresholds (higher versus lower), and for testing linear trends. RESULTS: Among 15 studies (5327 cases) the pooled odds ratio of VTE for the fourth versus first quarter was 3.92 (95 % confidence interval 1.61, 5.29) for FVIII level; and among 7 studies (3498 cases) 1.57 (1.32, 1.87) for FIX level. Comparing factor levels above, versus below, the 90th percentile, the estimated pooled odds ratios were 3.00 (2.10, 4.30) for FVIII; 1.77 (1.22, 2.56) for FIX; and 4.56 (2.73, 7.63) for both FVIII and FIX considered jointly. CONCLUSIONS: We confirm increases in risk of VTE across population distributions of FVIII and FIX levels. Levels above the 90th percentile have almost twice the risk for FIX level compared to levels below; three-fold risk for FVIII level; and almost five-fold risk for both FVIII and FIX levels elevated.

Enhanced in vivo and ex vivo thrombin generation after lower-leg trauma, but not after knee arthroscopy.

BACKGROUND: There is room for improvement of prevention of venous thromboembolism (VTE) after lower-leg cast application or knee arthroscopy. Information about the mechanism of clot formation in these patients may be useful to identify new prophylaxis targets. We aimed to study the effect of 1) lower-leg injury and 2) knee arthroscopy on thrombin generation. METHODS: A cross-sectional study was conducted using plasma samples of POT-(K)CAST trials to measure ex vivo thrombin generation (Calibrated Automated Thrombography [CAT]) and plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin (TAT), fibrinopeptide A (FPA). Plasma was obtained shortly after lower-leg trauma or before and after (< 4 h) knee arthroscopy. Participants were randomly selected from those who did not develop VTE. For aim 1, samples of 88 patients with lower-leg injury were compared with 89 control samples (i.e., preoperative samples of arthroscopy patients). Linear regression was used to obtain mean differences (or ratios if ln-retransformed because of skewedness) adjusted for age, sex, body mass index, comorbidities. For aim 2, pre- and postoperative samples of 85 arthroscopy patients were compared, for which mean changes were obtained. RESULTS: In patients with lower-leg injury (aim 1), endogenous thrombin potential, thrombin peak, velocity index, FPA and TAT were increased as compared with controls. In arthroscopy patients (aim 2), pre- and postoperative levels were similar for all parameters. CONCLUSION: Lower-leg trauma increases thrombin generation both ex vivo and in vivo, in contrast to knee arthroscopy. This may imply that the pathogenesis of VTE is different in both situations.

Association of ABO blood groups with venous thrombosis recurrence in middle-aged patients: insights from a weighted Cox analysis dedicated to ambispective design.

BACKGROUND: In studies of time-to-events, it is common to collect information about events that occurred before the inclusion in a prospective cohort. When the studied risk factors are independent of time, including both pre- and post-inclusion events in the analyses, generally referred to as relying on an ambispective design, increases the statistical power but may lead to a selection bias. In the field of venous thromboembolism (VT), ABO blood groups have been the subject of extensive research due to their substantial effect on VT risk. However, few studies have investigated their effect on the risk of VT recurrence. Motivated by the study of the association of genetically determined ABO blood groups with VT recurrence, we propose a methodology to include pre-inclusion events in the analysis of ambispective studies while avoiding the selection bias due to mortality. METHODS: This work relies on two independent cohorts of VT patients, the French MARTHA study built on an ambispective design and the Dutch MEGA study built on a standard prospective design. For the analysis of the MARTHA study, a weighted Cox model was developed where weights were defined by the inverse of the survival probability at the time of data collection about the events. Thanks to the collection of information on the vital status of patients, we could estimate the survival probabilities using a delayed-entry Cox model on the death risk. Finally, results obtained in both studies were then meta-analysed. RESULTS: In the combined sample totalling 2,752 patients including 993 recurrences, the A1 blood group has an increased risk (Hazard Ratio (HR) of 1.18, p = 4.2 × 10-3) compared with the O1 group, homogeneously in MARTHA and in MEGA. The same trend (HR = 1.19, p = 0.06) was observed for the less frequent A2 group. CONCLUSION: The proposed methodology increases the power of studies relying on an ambispective design which is frequent in epidemiologic studies about recurrent events. This approach allowed to clarify the association of ABO blood groups with the risk of VT recurrence. Besides, this methodology has an immediate field of application in the context of genome wide association studies.

Hepatic triglyceride content is intricately associated with numerous metabolites and biochemical pathways.

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is characterized by the pathological accumulation of triglycerides in hepatocytes and is associated with insulin resistance, atherogenic dyslipidaemia and cardiometabolic diseases. Thus far, the extent of metabolic dysregulation associated with hepatic triglyceride accumulation has not been fully addressed. In this study, we aimed to identify metabolites associated with hepatic triglyceride content (HTGC) and map these associations using network analysis. METHODS: To gain insight in the spectrum of metabolites associated with hepatic triglyceride accumulation, we performed a comprehensive plasma metabolomics screening of 1363 metabolites in apparently healthy middle aged (age 45-65) individuals (N = 496) in whom HTGC was measured by proton magnetic resonance spectroscopy. An atlas of metabolite-HTGC associations, based on univariate results, was created using correlation-based Gaussian graphical model (GGM) and genome scale metabolic model network analyses. Pathways associated with the clinical prognosis marker fibrosis 4 (FIB-4) index were tested using a closed global test. RESULTS: Our analyses revealed that 118 metabolites were univariately associated with HTGC (p-value <6.59 × 10-5 ), including 106 endogenous, 1 xenobiotic and 11 partially characterized/uncharacterized metabolites. These associations were mapped to several biological pathways including branched amino acids (BCAA), diglycerols, sphingomyelin, glucosyl-ceramide and lactosyl-ceramide. We also identified a novel possible HTGC-related pathway connecting glutamate, metabolonic lactone sulphate and X-15245 using the GGM network. These pathways were confirmed to be associated with the FIB-4 index as well. The full interactive metabolite-HTGC atlas is provided online: https://tofaquih.github.io/AtlasLiver/. CONCLUSIONS: The combined network and pathway analyses indicated extensive associations between BCAA and the lipids pathways with HTGC and the FIB-4 index. Moreover, we report a novel pathway glutamate-metabolonic lactone sulphate-X-15245 with a potential strong association with HTGC. These findings can aid elucidating HTGC metabolomic profiles and provide insight into novel drug targets for fibrosis-related outcomes.

Normal range CAG repeat size variations in the HTT gene are associated with an adverse lipoprotein profile partially mediated by body mass index.

Tandem cytosine-adenine-guanine (CAG) repeat sizes of 36 or more in the huntingtin gene (HTT) cause Huntington's disease (HD). Apart from neuropsychiatric complications, the disease is also accompanied by metabolic dysregulation and weight loss, which contribute to a progressive functional decline. Recent studies also reported an association between repeats below the pathogenic threshold (<36) for HD and body mass index (BMI), suggesting that HTT repeat sizes in the non-pathogenic range are associated with metabolic dysregulation. In this study, we hypothesized that HTT repeat sizes < 36 are associated with metabolite levels, possibly mediated through reduced BMI. We pooled data from three European cohorts (n = 10 228) with genotyped HTT CAG repeat size and metabolomic measurements. All 145 metabolites were measured on the same targeted platform in all studies. Multilevel mixed-effects analysis using the CAG repeat size in HTT identified 67 repeat size metabolite associations. Overall, the metabolomic profile associated with larger CAG repeat sizes in HTT were unfavorable-similar to those of higher risk of coronary artery disease and type 2 diabetes-and included elevated levels of amino acids, fatty acids, low-density lipoprotein (LDL)-, very low-density lipoprotein- and intermediate density lipoprotein (IDL)-related metabolites while with decreased levels of very large high-density lipoprotein (HDL)-related metabolites. Furthermore, the associations of 50 metabolites, in particular, specific very large HDL-related metabolites, were mediated by lower BMI. However, no mediation effect was found for 17 metabolites related to LDL and IDL. In conclusion, our findings indicate that large non-pathogenic CAG repeat sizes in HTT are associated with an unfavorable metabolomic profile despite their association with a lower BMI.

Sex-specific aspects of venous thromboembolism: What is new and what is next?

Men seem to have a higher intrinsic risk of venous thromboembolism (VTE) than women, regardless of age. To date, this difference has not been explained. By integrating state-of-the-art research presented at the International Society on Thrombosis and Haemostasis Congress of 2021 with the available literature, we address potential explanations for this intriguing risk difference between men and women. We discuss the role of exogenous and endogenous sex hormones as the most important known sex-specific determinants of VTE risk. In addition, we highlight clues on the role of sex hormones and VTE risk from clinical scenarios such as pregnancy and the polycystic ovary syndrome. Furthermore, we address new potential sex-specific risk factors and unanswered research questions, which could provide more insight in the intrinsic risk difference between men and women, such as body height and differences in body fat distribution, leading to dysregulation of metabolism and inflammation.

Association of Remote History of Venous Thrombosis With Risk of Venous Thrombosis After Age 70 Years.

Importance: Previous venous thrombosis (VT) is associated with risk of future VT, but quantification of risk over the life course is poorly understood. More information is needed for clinicians to understand the association of remote history of VT with the risk of VT in older patients. Objective: To assess the association between a remote history of VT and the development of VT in older age. Design, Setting, and Participants: The Age and Thrombosis, Acquired and Genetic Risk Factors in the Elderly case-control study enrolled patients 70 years and older with VT and control individuals 70 years and older without VT between June 2008 and August 2011. The Age and Thrombosis, Acquired and Genetic Risk Factors in the Elderly study is a 2-center, population-based case-control study that was conducted in Burlington, Vermont, in the US and in Leiden, the Netherlands. Consecutively diagnosed patients with an objectively proven episode of VT (deep vein thrombosis of the leg or pulmonary embolism) were included. Control individuals were identified in the same geographic areas as the patients and were randomly selected. Data were analyzed between May 2021 and October 2021. Exposures: Self-reported remote VT (occurring >10 years before to enrollment). Main Outcomes and Measures: The main outcome was the risk of VT at older age. The association of self-reported history of remote VT with VT at older age was assessed by calculating odds ratios (ORs) as estimates of relative risk with 95% CIs. Results: A total of 460 patients with VT and 456 control participants were included. There were slightly more women than men in both groups (60.2% of patients [n = 277] were women and 52.4% of control participants [n = 239] were women), and the mean (range) age of patients was 78.7 (70.0-100.9) years, which was similar to the control participants. Compared with individuals without remote VT, those with a remote history of VT had an increased risk of VT (OR, 2.54; 95% CI, 1.56-4.13). The crude risk estimate was robust to adjustment and time since remote VT, that is, individuals with a VT 10 to 30 years ago (OR, 2.74; 95% CI, 1.34-5.57) and those with a VT more than 30 years ago (OR, 2.42; 95% CI, 1.21-4.84) had a an increased risk of VT. The population-attributable fraction of a remote history of VT was 7.7%. Conclusions and Relevance: In this study, a remote history of VT was associated with risk of VT in older individuals. This quantification could assist clinicians in advising patients on VT prevention.

Association between cardiovascular risk factors and venous thromboembolism in the elderly.

BACKGROUND: The preponderance of the evidence supports no association between traditional cardiovascular risk factors and venous thromboembolism (VTE), other than obesity. There are limited data in older people. OBJECTIVES: To investigate whether cardiovascular risk factors (body mass index, smoking, alcohol intake, hypertension, and diabetes) are associated with the risk of VTE in elderly and to assess the combined effect between cardiovascular risk factors and genetic risk factors for VTE (factor V Leiden/prothrombin 20210A, positive family history of VTE, and non-O blood group). METHODS: The Age and Thrombosis, Acquired and Genetic risk factors in the Elderly study is a multicenter case-control study performed in Vermont, USA and Leiden, the Netherlands, comprising 401 cases with first VTE and 431 control subjects, all aged ≥70 years. To assess the risk of VTE, odds ratios (OR) with 95% confidence intervals (CIs) were calculated, adjusting for potential confounders. RESULTS: Both height and weight were positively associated with VTE risk: the ORs were 2.2 (95% CI, 1.2-3.9) and 1.5 (95% CI, 1.0-2.4) in the top quartile for height and weight separately. This risk was more pronounced for unprovoked VTE. Smoking, alcohol intake, and diabetes were not associated with VTE. Higher systolic and diastolic blood pressure and hypertension were associated with a decreased risk of VTE. In the presence of a genetic predisposition, height and weight further increased the risk of VTE. CONCLUSIONS: In the elderly, height and weight are positively associated with the risk of VTE. With genetic predisposition, higher levels of height and weight further increase the risk of VTE.

The influence of corn trypsin inhibitor on the contribution of coagulation determinants to the Technoclone Thrombin Generation Assay (TGA) and the Calibrated Automated Thrombogram (CAT).

In thrombin generation (TG) assays, regarded as global coagulation tests, contact activation is considered a major problem which can be eliminated by adding Corn Trypsin Inhibitor (CTI). In previous studies, however, venous thrombosis risk prediction using TG assays did not improve after CTI addition. However, it is unknown whether CTI addition could help to detect subtle but relevant nuances in determinants of TG, making the assay more suitable to detect disturbances in the coagulation system. This study's objective was to assess whether the addition of CTI is associated with a broader contribution of individual coagulation factors to the total amount of thrombin formed in Calibrated Automated Thrombogram (CAT) and Technoclone Thrombin Generation Assay (TGA). Thrombin generation was measured in 326 healthy individuals from THE VTE study at very low tissue factor concentrations, with and without addition of CTI prior to blood sampling. The influence of several coagulation factors on total amount of thrombin formed, i.e. area under the curve (AUC) or endogenous thrombin potential (ETP), was analysed using multiple linear regression with standardisation of all values resulting in Z-scores with 95% confidence intervals (95%CI). Association between coagulation factors and TG changed minimally after addition of CTI. Largest changes after CTI addition were found for following factors: for CAT: free protein S (from 0.00 (95%CI -0.12 to 0.12) to -0.29 (95%CI -0.43 to -0.15)) and protein S (from -0.05 (95%CI -0.18 to 0.08) to -0.21 (95%CI -0.37 to -0.05)); for TGA: antithrombin (from -0.11 (-0.23 to 0.02) to -0.19 (-0.30 to -0.07)), factor VIII (from 0.15 (0.03 to 0.27) to 0.24 (0.13 to 0.36)) and fibrinogen (from 0.12 (-0.01 to 0.26) to 0.19 (0.06 to 0.32)). In conclusion, there is no clear trend towards a broader contribution of coagulation factors in samples handled with CTI compared with those handled without CTI.

The EHA Research Roadmap: Blood Coagulation and Hemostatic Disorders.

In 2016, the European Hematology Association (EHA) published the EHA Roadmap for European Hematology Research1 aiming to highlight achievements in the diagnostics and treatment of blood disorders, and to better inform European policy makers and other stakeholders about the urgent clinical and scientific needs and priorities in the field of hematology. Each section was coordinated by 1-2 section editors who were leading international experts in the field. In the 5 years that have followed, advances in the field of hematology have been plentiful. As such, EHA is pleased to present an updated Research Roadmap, now including 11 sections, each of which will be published separately. The updated EHA Research Roadmap identifies the most urgent priorities in hematology research and clinical science, therefore supporting a more informed, focused, and ideally funded future for European hematology research. The 11 EHA Research Roadmap sections include Normal Hematopoiesis; Malignant Lymphoid Diseases; Malignant Myeloid Diseases; Anemias and Related Diseases; Platelet Disorders; Blood Coagulation and Hemostatic Disorders; Transfusion Medicine; Infections in Hematology; Hematopoietic Stem Cell Transplantation; CAR-T and Other Cell-based Immune Therapies; and Gene Therapy.

D-dimer, thrombin generation, and risk of a first venous thrombosis in the elderly.

BACKGROUND: A high D-dimer level and parameters of the thrombin generation (TG) potential are associated with the risk of a first venous thrombosis (VT) in young and middle-aged populations. OBJECTIVES: To investigate whether D-dimer and TG potential (lag-time, time-to-peak [ttPeak], peak thrombin, endogenous thrombin potential [ETP], and velocity index), are associated with the risk of a first VT in those aged 70 years and older. METHODS: We included 215 patients with a first VT and 358 controls, all aged >70 years, from the Age and Thrombosis, Acquired and Genetic Risk Factors in the Elderly (AT-AGE) study. To assess the risk of VT, odds ratios with 95% confidence intervals (CIs) were estimated using logistic regression analysis. RESULTS: D-dimer and all TG parameters except lag time were associated with an increased risk of VT in a dose-response manner. Comparing the fourth with the first quartile (for ttPeak comparing the first with the fourth quartile), risk estimates were: 7.8 (95% CI, 4.0-15.0) for peak, 2.0 (95% CI, 1.2-3.3) for ttPeak, 9.1 (95% CI, 4.4-18.9) for ETP, and 11.5 (95% CI, 5.7-23.3) for velocity index. Comparing the highest quartile of D-dimer with the lowest, the risk was 7.7-fold increased (95% CI, 4.0-14.8). Furthermore, all factors also increased the risk of VT after dichotomizing at more extreme cutoff values. The risk of VT was further increased in the presence of multiple prothrombotic TG parameters and elevated D-dimer level or in combination with prothrombotic mutations. CONCLUSIONS: D-dimer and TG parameters (except lag time) are associated with the risk of first VT in elderly population.

Agreement of aptamer proteomics with standard methods for measuring venous thrombosis biomarkers.

BACKGROUND: Venous thromboembolism (VTE) is a complex disease with an incidence rate of about 1 in 1000 per year. Despite the availability of validated biomarkers for VTE, unprovoked events account for 50% of first events. Therefore, emerging high-throughput proteomics are promising methods for the expansion of VTE biomarkers. One such promising high-throughput platform is SomaScan, which uses a large library of synthetic oligonucleotide ligands known as aptamers to measure thousands of proteins. OBJECTIVE: The aim of this study was to evaluate the viability of the aptamer-based SomaScan platform for VTE studies by examining its agreement with standard laboratory methods. METHODS: We examined the agreement between eight established VTE biomarkers measured by SomaScan and standard laboratory immunoassay and viscosity-based instruments in 54 individuals (27 cases and 27 controls) from the Thrombophilia, Hypercoagulability and Environmental Risks in Venous Thromboembolism study. We performed the agreement analysis by using a regression model and predicting the estimates and the 95% prediction interval (PI) of the laboratory instrument values using SomaScan values. RESULTS: SomaScan measurements exhibited overall poor agreement, particularly for D-dimer (average fit, 492.7 ng/mL; 95% PI, 110.0-1998.2) and fibrinogen (average fit, 3.3 g/L; 95% PI, 2.0-4.7). CONCLUSION: Our results indicate that SomaScan measurement had poor agreement with the standard laboratory measurements. These results may explain why some genome-wide association studies with VTE proteins measured by SomaScan did not confirm previously identified loci. Therefore, SomaScan should be considered with caution in VTE studies.

Correction: Prediction of recurrent venous thrombosis in all patients with a first venous thrombotic event: The Leiden Thrombosis Recurrence Risk Prediction model (L-TRRiP).

[This corrects the article DOI: 10.1371/journal.pmed.1002883.].

Venous thrombosis with oral postmenopausal hormone therapy: Roles of activated protein C resistance and tissue factor pathway inhibitor.

BACKGROUND: Oral postmenopausal hormone therapy (HT) increases the risk of venous thrombosis (VT). We postulated that activated protein C (APC) resistance induced by HT is one of the mechanisms causing VT, and also assessed the role of one of the main determinants of APC resistance (i.e., tissue factor pathway inhibitor [TFPI]). METHODS: We performed a nested case-control study embedded within two Women's Health Initiative hormone trials. Women were randomized to hormone therapy or placebo. Biomarkers were measured at baseline and after 1 year in 217 cases and 817 controls. RESULTS: Increased APC resistance and decreased TFPI at baseline were associated with VT (odds ratio 1.20-2.06). However, women with such prothrombotic profile at baseline did not have further increased risk of VT when randomized to HT compared with placebo. Although there was no change in APC resistance or TFPI in placebo group after 1 year, HT group showed prothrombotic changes in the biomarkers (i.e., an increase in APC resistance) (mean [standard deviation] 0.39 [0.54]) and decrease in TFPI (-0.21 [0.50]: free TFPI, -0.24 [0.22]: TFPI activity -0.22 [0.20]: total TFPI). However, HT induced prothrombotic change in biomarkers did not increase risk of VT. CONCLUSION: Women with prothrombotic levels of APC resistance and TFPI at baseline were not at increased risk of VT when randomized to HT compared with placebo. This suggests that testing for these biomarkers before starting HT is not required. HT led to prothrombotic change in these biomarkers after one year, but this did not relate to increased risk of VT.