Treatment of patients with rare bleeding disorders in the Netherlands:Real-life data from the RBiN study

Background Patients with rare inherited bleeding disorders (RBDs) exhibit hemorrhagic symptoms, varying in type and severity, often requiring only on-demand treatment. Prolonged bleeding after invasive procedures is common. Adequate peri-procedural therapy may reduce this bleeding risk. Objective To describe general treatment plans of RBD patients and evaluate the use of peri-procedural hemostatic therapy. Methods In the Rare Bleeding Disorders in the Netherlands (RBiN) study, RBD patients from all six Dutch Hemophilia Treatment Centers were included. General treatment plans were extracted from patient files. Patients with a dental or surgical procedure in their history were interviewed about use of peri-procedural treatment and bleeding complications. Results Two-hundred sixty-three patients with a rare coagulation factor deficiency or fibrinolytic disorder were included. Eighty-four percent had a documented general treatment plan. General treatment plans of patients with the same RBD were heterogeneous, particularly in factor XI deficiency. Overall, 308 dental and 408 surgical procedures were reported. Bleeding occurred in 50% of dental and 53% of surgical procedures performed without hemostatic treatment and in 28% of dental and 19% of surgical procedures performed with hemostatic treatment. Not only patients with severe RBDs, but also patients with mild deficiencies, experienced increased bleeding without proper hemostatic treatment. Conclusion Large heterogeneity in general treatment plans of RBD patients was found. Bleeding after invasive procedures was reported frequently, both before and after RBD diagnosis, irrespective of factor activity levels and particularly when peri-procedural treatment was omitted. Improved guidelines should include uniform recommendations for most appropriate hemostatic products per RBD and emphasize the relevance of individual bleeding history

Targeted exome analysis in patients with rare bleeding disorders:data from the Rare Bleeding Disorders in the Netherlands study

Background: Rare coagulation factor deficiencies and disorders of fibrinolysis (defined as rare bleeding disorders [RBDs]) present with a heterogeneous bleeding phenotype, and bleeding severity is difficult to predict. Objectives: Describe underlying rare genetic variants in the Dutch RBD population and investigate the relationship between genotype, laboratory phenotype, and clinical phenotype. Methods: The Rare Bleeding Disorders in the Netherlands is a cross-sectional, nationwide study conducted between October 1, 2017, and November 30, 2019. Bleeding scores and blood samples were collected during a single study visit. Coagulation factor levels were measured centrally, and targeted exome analysis was performed on 156 genes involved in thrombosis and hemostasis. Pathogenicity was assigned according to the Association for Clinical Genetic Science guidelines. Results: Rare genetic variants specific to the diagnosed RBD were found in 132 of 156 patients (85%). Of the 214 rare genetic variants identified, 57% (n = 123) were clearly pathogenic, 19% (n = 40) were likely pathogenic, and 24% (n = 51) were variants of unknown significance. No explanatory genetic variants were found in patients with plasminogen activator inhibitor type 1 deficiency or hyperfibrinolysis. A correlation existed between factor activity levels and the presence of a genetic variant in the corresponding gene in patients with rare coagulation factor deficiencies and alpha-2-antiplasmin deficiency. Co-occurrence of multiple genetic variants was present in a quarter of patients, but effect on phenotype remains unclear. Conclusion: Targeted exome analysis may offer advantages over single-gene analysis, emphasized by a number of combined deficiencies in this study. Further studies are required to determine the role of co-occurring hemostasis gene variants on the bleeding phenotype in RBDs.</p

Targeted exome analysis in patients with rare bleeding disorders: data from the Rare Bleeding Disorders in the Netherlands study

Background: Rare coagulation factor deficiencies and disorders of fibrinolysis (defined as rare bleeding disorders [RBDs]) present with a heterogeneous bleeding phenotype, and bleeding severity is difficult to predict. Objectives: Describe underlying rare genetic variants in the Dutch RBD population and investigate the relationship between genotype, laboratory phenotype, and clinical phenotype. Methods: The Rare Bleeding Disorders in the Netherlands is a cross-sectional, nationwide study conducted between October 1, 2017, and November 30, 2019. Bleeding scores and blood samples were collected during a single study visit. Coagulation factor levels were measured centrally, and targeted exome analysis was performed on 156 genes involved in thrombosis and hemostasis. Pathogenicity was assigned according to the Association for Clinical Genetic Science guidelines. Results: Rare genetic variants specific to the diagnosed RBD were found in 132 of 156 patients (85%). Of the 214 rare genetic variants identified, 57% (n = 123) were clearly pathogenic, 19% (n = 40) were likely pathogenic, and 24% (n = 51) were variants of unknown significance. No explanatory genetic variants were found in patients with plasminogen activator inhibitor type 1 deficiency or hyperfibrinolysis. A correlation existed between factor activity levels and the presence of a genetic variant in the corresponding gene in patients with rare coagulation factor deficiencies and alpha-2-antiplasmin deficiency. Co-occurrence of multiple genetic variants was present in a quarter of patients, but effect on phenotype remains unclear. Conclusion: Targeted exome analysis may offer advantages over single-gene analysis, emphasized by a number of combined deficiencies in this study. Further studies are required to determine the role of co-occurring hemostasis gene variants on the bleeding phenotype in RBDs

Dosing of factor VIII concentrate by ideal body weight is more accurate in overweight and obese haemophilia A patients

Aims: Under- and, especially, overdosing of replacement therapy in haemophilia A patients may be prevented by application of other morphometric variables than body weight (BW) to dose factor VIII (FVIII) concentrates. Therefore, we aimed to investigate which morphometric variables best describe interindividual variability (IIV) of FVIII concentrate pharmacokinetic (PK) parameters. Methods: PK profiling was performed by measuring 3 FVIII levels after a standardized dose of 50 IU kg−1 FVIII concentrate. A populat

Sports participation and physical activity in patients with von Willebrand disease

Introduction: Patients with bleeding disorders may experience limitations in sports participation and physical activity. Several studies on sports participation have been performed in haemophilia patients, but studies in patients with von Willebrand disease (VWD) are lacking. Aim: We assessed the sports participation and physical activity of a large cohort of VWD patients. Methods: Patients were included from the “WiN study

Mortality, life expectancy, and causes of death of persons with hemophilia in the Netherlands 2001–2018

Background: Treatment of patients with hemophilia has advanced over the past decades, but it is unknown whether this has resulted in a normal life expectancy in the Netherlands. Objective: This observational cohort study aimed to assess all-cause and cause-specific mortality in patients with hemophilia in the Netherlands between 2001 and 2018 and to compare mortality and life expectancy with previous survival assessments from 1973 onward. Patients/methods: All 1066 patients with hemophilia who participated in a nationwide survey in 2001 were followed until July 2018. Results: Information on 1031 individuals (97%) was available, of whom 142 (14%) deceased during follow-up. Compared with the general Dutch male population, mortality of patients with hemophilia was still increased (standardized mortality ratio: 1.4, 95% confidence interval: 1.2–1.7). Intracranial bleeding and malignancies were the most common causes of death. Estimated median life expectancy of patients with hemophilia was 77 years, 6 years lower than the median life expectancy of the general Dutch male population (83 years). Over the past 45 years, death rates of patients with hemophilia have consistently decreased, approaching the survival experience of the general population. Over the past decades, mortality due to human immunodeficiency virus and hepatitis C virus infections has decreased, death due to intracranial hemorrhages has increased, and death due to ischemic hear

Heavy menstrual bleeding on direct factor Xa inhibitors: Rationale and design of the MEDEA study

Background: In premenopausal women, treatment with direct oral factor Xa inhibitors is associated with an increased risk of heavy menstrual bleeding (HMB) compared with vitamin K antagonists (VKA). Treatment with the direct oral thrombin inhibitor dabigatran appears to be associated with a reduced risk of HMB compared with VKA. These findings come from small observational studies or post hoc analyses of trials in which HMB was not a primary outcome. Use of tranexamic acid during the menstrual period may be effective in patients with HMB, but prospective data regarding efficacy and safety in patients on anticoagulant treatment are lacking. Rationale and Design: A direct comparison of a factor Xa inhibitor and a thrombin inhibitor with HMB as primary outcome, as well as an evaluation of the effects of adding tranexamic acid in women with anticoagulant-associated HMB is highly relevant for clinical practice. The MEDEA study is a randomized, open-label, pragmatic clinical trial to evaluate management strategies in premenopausal women with HMB associated with factor Xa inhibitor therapy. Outcomes: Women using factor Xa inhibitors with proven HMB, as assessed by a pictorial blood loss assessment chart (PBAC) score of >150, will be randomized to one of three study arms: (i) switch to dabigatran; (ii) continue factor Xa inhibitor with addition of tranexamic acid during the menstrual period; or (iii) continue factor Xa inhibitor without intervention. The primary outcome is the difference in PBAC score before and after randomization. Here, we present the rationale and highlight several unique features in the design of the study

ADAMTS-13 and bleeding phenotype in von Willebrand disease

Background: The bleeding phenotype of von Willebrand disease (VWD) varies highly between patients and can only partly be explained by von Willebrand factor (VWF) parameters. By cleaving large VWF multimers into smaller, less active multimers, ADAMTS-13 is an important regulator of VWF activity. However, it is unknown what the role of ADAMTS-13 is in individuals with VWD. Objectives: We therefore studied how ADAMTS-13 activity is associated with the laboratory and bleeding phenotype in individuals with VWD. Methods: We measured ADAMTS-13 activity using the fluorescence resonance energy transfer substrate VWF 73 assay in 638 individuals with VWD in the nationwide cross-sectional Willebrand in the Netherlands study and in 36 healthy controls. The bleeding phenotype was assessed using the Tosetto bleeding score. Results: ADAMTS-13 activity was similar in individuals with VWD (109% ± 20.6%) and controls (110% ± 19.7%). ADAMTS-13 activity was higher in individuals with VWD with type 3 than those with type 1 (mean difference, 11.8%; 95% confidence interval [CI], 2.9%-20.8%) or type 2 (mean difference, 16.1%; 95% CI, 7.1%-25.1%). ADAMTS-13 activity was not associated with the Tosetto bleeding score (0.1 Tosetto bleeding score increase per 10% ADAMTS-13 increase, 95% CI, −0.2 to 0.3). Furthermore, ADAMTS-13 activity did not differ between individuals with and without a bleeding event during the year preceding blood sampling (mean difference, 1.4%; 95% CI, −2.1% to 4.9%). Conclusion: ADAMTS-13 activity was highest in individuals with type 3 VWD, but it had only minor associations with VWF parameters. ADAMTS-13 activity does not influence the bleeding phenotype in individuals with VWD

Bleeding severity in patients with rare bleeding disorders: real-life data from the RBiN study

Patients with hereditary rare bleeding disorders (RBDs) present with diverse hemorrhagic symptoms. Correlation between factor activity levels and clinical bleeding severity is poor for most RBDs. Threshold factor activity levels have been previously described in relation to bleeding severity but have not yet been validated. The Rare Bleeding Disorders in the Netherlands (RBiN) study is a nationwide cross-sectional study of patients registered in all 6 Dutch Haemophilia Treatment Centers with a known RBD and who are age 1 to 99 years. Bleeding scores were determined, and laboratory and clinical data were extracted from patient files. In all, 263 patients were included, of whom 202 (77%) attended the scheduled study visit. The median International Society of Thrombosis and Haemostasis (ISTH) bleeding assessment tool (BAT) score was 9. Correlations between baseline factor activity levels and ISTH BAT scores were strong for deficiencies in factor II (FII) (r = -0.792) and FX (r = -0.838) and were moderate for deficiencies of fibrinogen (r = -0.683), FV (r = -0.623), FVII (r = -0.516), FXIII (r = -0.516), and α2-antiplasmin (r = -0.594). There was no correlation for FXI deficiency (r = -0.218). The RBD BAT identified more women (94% vs 83%) and children (100% vs 71%) with an RBD than the ISTH BAT did. Importantly, 48% of patients had more severe bleeding than predicted for their baseline factor activity level. In addition, 34% of patients were predicted to be asymptomatic, but they actually had grade 2 (31%) or 3 (3%) bleeding. Bleeding severity in patients with RBDs is more pronounced than previously anticipated. The previously determined threshold factor activity levels to ensure no (spontaneous) bleeding in patients with an RBD are inaccurate. This trial was registered at www.clinicaltrials.gov as #NCT03347591

High prevalence of postpartum hemorrhage in women with rare bleeding disorders in the Netherlands: retrospective data from the RBiN study

BACKGROUND: Women with rare bleeding disorders (RBDs), including coagulation factor deficiencies and fibrinolytic disorders, may have a higher risk of postpartum hemorrhage (PPH). Information on this patient category is lacking in the existing PPH guidelines because data on PPH in patients with RBDs are scarce. OBJECTIVE: To describe the prevalence of PPH in women with an RBD and evaluate the use of peripartum hemostatic prophylaxis. METHODS: In the Rare Bleeding Disorders in the Netherlands (RBiN) study, patients with RBDs (n = 263) were included from all 6 Dutch hemophilia treatment centers. Patient-reported information on delivery, peripartum hemostatic prophylaxis, and occurrence of PPH was collected retrospectively. If available, information about the precise volume of postpartum blood loss was extracted from electronic patient files. PPH was defined as blood loss ≥500 mL (World Health Organization guideline). RESULTS: A total of 244 pregnancies, including 193 livebirths, were reported by 85 women. A considerable proportion of these women experienced PPH, ranging from 30% in factor V deficiency to 100% in hyperfibrinolysis. Overall, PPH was reported in 44% of deliveries performed with and 53% of deliveries performed without administration of peripartum hemostatic prophylaxis. Blood loss was significantly higher in deliveries without administration of hemostatic prophylaxis (median 1000 mL) compared to deliveries with administration of prophylaxis (median 400 mL) (p = 0.011). Patients with relatively mild deficiencies also frequently experienced PPH when peripartum hemostatic prophylaxis was omitted. CONCLUSION: PPH is common in rare coagulation factor deficiencies, both severe and mild, and fibrinolytic disorders, especially when peripartum prophylactic hemostatic treatment was not administered. The use of prophylactic hemostatic treatment was associated with less postpartum blood loss