Elevated von Willebrand factor levels during heavy menstrual bleeding episodes limit the diagnostic utility for von Willebrand disease

Hemoglobin concentration and body mass index are determinants of plasma von Willebrand factor and factor VIII levels

BACKGROUND

Von Willebrand Disease (VWD) is the most common inherited bleeding disorder. VWD is characterized by an abnormal quantity or quality of von Willebrand Factor (VWF). Anemia is often found at presentation for a bleeding disorder evaluation due to chronic blood loss.

OBJECTIVES/HYPOTHESIS

We hypothesized that anemia is associated with elevations in both VWF and factor VIII (FVIII) over baseline. We also hypothesized that obesity would be associated with increased levels of VWF.

METHODS

We conducted a single-center review of the electronic health record for patients that had proximal von Willebrand profiles and Hb data.

RESULTS

We identified 4552 unique subjects with VWF studies and a CBC within 24 h. We found that decreasing hemoglobin inversely correlated with VWF antigen, VWF ristocetin cofactor activity, and FVIII activity. We also found that obesity and Black race were independently associated with increased VWF antigen, activity, and FVIII activity. Hb, race, and body mass index (BMI) continued to be determinants of VWF and FVIII levels in multivariable analysis.

CONCLUSION

Our study demonstrates that anemia, race, and BMI were found to be associated with elevation of VWF antigen, VWF activity, and FVIII levels. As many individuals with anemia present for evaluation for a bleeding disorder, these variables need to be considered.

KEY POINTS

- Anemia was found to be associated with elevation of VWF antigen, VWF activity and FVIII levels. - Testing von Willebrand factor at times of anemia may mask a diagnosis of von Willebrand Disease.

von Willebrand disease

von Willebrand disease (VWD) is the most common inherited bleeding disorder. The disorder is characterized by excessive mucocutaneous bleeding. The most common bleeding manifestations of this condition include nosebleeds, bruising, bleeding from minor wounds, menorrhagia or postpartum bleeding in women as well as bleeding after surgery. Other less frequent symptoms include gastrointestinal bleeding, haematomas or haemarthroses. VWD pathophysiology is complex and results from defects in von Willebrand factor (VWF) glycoprotein. Quantitative deficiencies are responsible for type 1 VWD with a partial decrease of VWF and type 3 with the complete absence of VWF. Qualitative abnormalities cause type 2 VWD, being further divided into types 2A, 2B, 2M and 2N. Although common, VWD is at risk of misdiagnosis, overdiagnosis and underdiagnosis owing to several factors, including complex diagnosis, variability of bleeding symptoms, presence of external variables (blood groups and other physiological modifiers such as exercise, thyroid hormones, oestrogens, and ageing), and lack of disease awareness among non-specialist health-care providers. Establishing the correct VWD diagnosis requires an array of specialized phenotypic assays and/or molecular genetic testing of the VWF gene. The management of bleeding includes increasing endogenous VWF levels with desmopressin or infusion of exogenous VWF concentrates (plasma-derived or recombinant). Fibrinolytic inhibitors, topical haemostatic agents and hormonal therapies are used as effective adjunctive measures.

Early diagnosis of persons with von Willebrand disease using a machine learning algorithm and real-world data

BACKGROUND

Von Willebrand disease (VWD) is underdiagnosed, often delaying treatment. VWD claims coding is limited and includes no severity qualifiers; improved identification methods for VWD are needed. The aim of this study is to identify and characterize undiagnosed symptomatic persons with VWD in the US from medical insurance claims using predictive machine learning (ML) models.

RESEARCH DESIGN AND METHODS

Diagnosed and potentially undiagnosed VWD cohorts were defined using Komodo longitudinal US claims data (January 2015-March 2020). ML models were built using key characteristics predictive of VWD diagnosis from the diagnosed cohort. Two ML models predicted VWD diagnosis with the highest accuracy in females (random forest; 84%) and males (gradient boosting machine; 85%). Undiagnosed persons suspected to have VWD were identified using an 80% cutoff probability; profiles of key characteristics were constructed.

RESULTS

The trained ML models were applied to the undiagnosed cohort (28,463 females; 20,439 males) with suspected VWD. Fifty-two percent of undiagnosed females had heavy menstrual bleeding, a key pre-diagnosis symptom. Undiagnosed males tended to have more frequent medical procedures, hospitalizations, and emergency room visits compared with undiagnosed females.

CONCLUSIONS

ML algorithms successfully identified potentially undiagnosed symptomatic people with VWD, although many may remain undiagnosed and undertreated. External validation of the algorithms is recommended.

The necessity of repeat testing for von Willebrand disease in adult patients with mild to moderate bleeding disorders

BACKGROUND

In patients with mild-to-moderate bleeding disorders (MBD), von Willebrand disease (VWD) is diagnosed at von Willebrand factor (VWF) levels ≤50 IU/dL. Although VWF levels are unstable, repeated testing for VWD diagnosis is not necessarily advised in recent guidelines.

OBJECTIVES

To analyze the relevance of repeated VWF testing to diagnose VWD in patients with MBD.

METHODS

Data of 277 patients with MBD from the Vienna Bleeding Biobank with at least 2 separate assessments of VWF antigen (VWF:Ag) and activity (VWF:Act) were analyzed.

RESULTS

In repeated VWF measurements, 36 patients (13.0%) had "changing" VWF levels (≤/>50 IU/dL), 27 (9.7%) had persistent levels ≤50 IU/dL ("pathologic"), and 214 (77.3%) had levels >50 IU/dL ("normal"). Of the 36 changing patients, 22 (61%) were diagnosed with VWD at baseline, whereas the others only met VWD diagnostic criteria at repeated measurements. Using logistic regression, we estimated a probability of change of 26.4% (95% CI, 12.5-47.4) at baseline VWF levels of 30 IU/dL, 50.8% (95% CI, 35.6-65.8) at 50 IU/dL, 18.8% (95% CI, 12.3-27.6) at 60 IU/dL, and 1.2% (95% CI, 0.3-4.9) at 80 IU/dL. Baseline VWF was a strong predictor for changing status (Χ2 = 49.9; P < .001), while age, sex, Vicenza score, and blood type O had limited added value (Χ2 = 5.1; P = .278). Baseline VWF:Ag or VWF:Act cutoffs of 80 IU/dL had negative predictive values of 98.1% and 99.1% for changing status, respectively.

CONCLUSION

Our data emphasize an overlap between patients with VWD and MBD with bleeding disorder of unknown cause and underline the need for repeated VWF testing, especially in patients with VWF levels <80 IU/dL.

Investigating patients for bleeding disorders when most of the "usual" ones have been ruled out

A State of the Art lecture titled "Investigating Patients for Bleeding Disorders When Most of the Usual Ones Have Been Ruled Out" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023. Mild to moderate bleeding disorders (MBDs) in patients in whom no diagnosis of an established disorder, such as platelet function defect, von Willebrand disease, or a coagulation factor deficiency, can be identified are classified as bleeding disorders of unknown cause (BDUCs). Prospective data from the Vienna Bleeding Biobank and other studies have revealed a high proportion of BDUCs of up to 70% among patients with MBD who have a similar bleeding phenotype as other MBDs. As BDUC is a diagnosis of exclusion, the accuracy of the diagnostic workup is essential. For example, repeated testing for von Willebrand disease should be considered if von Willebrand factor values are <80 IU/dL. Current evidence does not support the clinical use of global assays such as thromboelastography, platelet function analyzer, or thrombin generation potential. Rare and novel bleeding disorders due to genetic variants in fibrinolytic factors or natural anticoagulants are rare and should only be analyzed in patients with specific phenotypes and a clear family history. In BDUC, blood group O was identified as a risk factor for increased bleeding severity and bleeding risk after hemostatic challenges. Future studies should improve the phenotypical characterization and ideally identify novel risk factors in BDUC, as a multifactorial pathogenesis is suspected. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress.

Initial von Willebrand factor antigen values in adolescent females predict future values

INTRODUCTION

Diagnosing von Willebrand Disease (VWD) in adolescent females is challenging as menstruation and physiologic stress elevate von Willebrand factor (VWF) laboratory values.

AIM

To develop a VWF prediction model for adolescent females based on initial VWF results.

METHODS

We identified female patients aged 9 to 21 years with any VWF laboratory test over a 5-year period (2017-2021) at any Texas Children's Hospital facility. Patient demographics, VWF testing, haemoglobin concentration, serum ferritin and site of clinical testing were collected (initial and subsequent laboratory evaluations). A Bayesian linear regression model was developed. Prediction intervals were analysed to identify thresholds for patients in whom repeat testing was unlikely to identify low VWF levels (< 50%), consistent with VWD.

RESULTS

A total of 6125 adolescent females underwent VWF testing; 1204 (19.7%) had repeat testing. Based on the prediction model, initial VWF antigen values of 80%, 90% and ≥100% carried a 92.6%, 96.6% and ≥98.0% probability of having repeat normal repeat VWF values, respectively. Subjects assessed in outpatient adolescent medicine or gynaecology clinics were more likely to have low VWF values compared to those assessed in the acute care setting (p < .001). Median presenting haemoglobin and serum ferritin were 12.4 g/dL and 13 ng/mL, respectively and were similar in those with normal versus low VWF antigen values.

CONCLUSION

Repeat testing in adolescent females whose initial VWF antigen values are ≥90% is unlikely to identify additional patients with VWD. Iron deficiency screening should be performed in all adolescent females.

Building the foundation for a community-generated national research blueprint for inherited bleeding disorders: research to advance the health of people with inherited bleeding disorders with the potential to menstruate

BACKGROUND

People who have or had the potential to menstruate (PPM) with inherited bleeding disorders (BD) face particular challenges receiving appropriate diagnosis and care and participating in research. As part of an initiative to create a National Research Blueprint for future decades of research, the National Hemophilia Foundation (NHF) and American Thrombosis and Hemostasis Network conducted extensive all-stakeholder consultations to identify the priorities of PPM with inherited BDs and those who care for them.

RESEARCH DESIGN AND METHODS

Working group (WG) 4 of the NHF State of the Science Research Summit distilled community-identified priorities for PPM with inherited BDs into concrete research questions and scored their feasibility, impact, and risk.

RESULTS

WG4 identified important gaps in the foundational knowledge upon which to base optimal diagnosis and care for PPM with inherited BDs. They defined 44 top-priority research questions concerning lifespan sex biology, pregnancy and the post-partum context, uterine physiology and bleeding, bone and joint health, health care delivery, and patient-reported outcomes and quality-of-life.

CONCLUSIONS

The needs of PPM will best be advanced with research designed across the spectrum of sex and gender biology, with methodologies and outcome measures tailored to this population, involving them throughout.

The diagnosis, natural history, and management of von Willebrand disease in women in the age of guidelines

INTRODUCTION

Women and girls with bleeding disorders face multiple bleeding challenges throughout their life. The most significant morbidity and mortality are due to heavy menstrual bleeding and postpartum hemorrhage in their reproductive years. The ASH/ISTH/NHF/WFH 2021 guidelines on diagnosing and managing von Willebrand disease (VWD) provide several new updates.

AREAS COVERED

Women with VWD have a higher prevalence of heavy menstrual bleeding. The subpopulation of adolescents is particularly vulnerable, as the diagnosis is often delayed with increased comorbidity of iron deficiency anemia and associated symptoms. A detailed review is done on the prevalence of bleeding-related complications, especially heavy menstrual bleeding (HMB) and post-partum hemorrhage (PPH). The management strategies are also reviewed in detail, with a specific focus on the target factor levels and the use of antifibrinolytics.

EXPERT OPINION

The 2021 ASH/ISTH/NHF/WFH diagnostic and management recommendations are reviewed with a specific focus on hormonal methods of HMB management and antifibrinolytics in this situation. The reviewed topics include neuraxial anesthesia, factor cutoff, and tranexamic acid use in the postpartum period.

Diagnostic pitfalls and conundrums in type 1 von Willebrand disease

Most people with von Willebrand disease (VWD) have a partial quantitative deficiency of plasma von Willebrand factor (VWF) or type 1 VWD. In contrast to type 2 and type 3 VWD, laboratory assays will not always establish the diagnosis in type 1 VWD. This is because plasma VWF levels in type 1 VWD, especially those with levels closer to 50 IU/dL, overlap with the general population. Assessment is further complicated by increased plasma VWF levels in response to physiologic stressors or aging. Diagnosis of those with type 1 VWD with plasma VWF levels 30 to 50 IU/dL (previously referred to as "low VWF") requires expert assessment of bleeding phenotype as well as an understanding of the limitations of both bleeding assessment tools (BATs) and laboratory testing. Using the available evidence and highlighting research gaps, we discuss common dilemmas facing providers relating to assessment of adolescents, transition from pediatrics to adult care, and older individuals with type 1 VWD.

High Prevalence of Congenital Factor VII (FVII) Deficiency in Adolescent Females with Heavy Menstrual Bleeding and Iron Deficiency Anemia

STUDY OBJECTIVE

To examine the clinical characteristics and prevalence of congenital bleeding disorders (CBDs), with emphasis on congenital factor VII (FVII) deficiency and other rare bleeding disorders, in adolescent and young adult females referred to a hemophilia treatment center (HTC) for evaluation and management of heavy menstrual bleeding (HMB) and iron deficiency anemia (IDA) DESIGN: In this single-center retrospective study, we reviewed the clinical characteristics and prevalence of CBDs in postmenarchal females, younger than 22 years of age, referred to an HTC from 2015 to 2021 for evaluation of HMB with or without IDA.

RESULTS

One hundred females, with a mean age of 15 years (range 9-20 years), met initial study criteria, and 95 were included in the final analysis. Forty-five (47%) females were ultimately diagnosed with a CBD. The most prevalent diagnoses were FVII deficiency and type 1 von Willebrand disease (VWD) (42.3%, n = 19 each). Forty-two percent of patients with FVII deficiency had a low-for-age FVII activity level, 21.1% were only positive for the FVII R353Q variant associated with borderline FVII levels, whereas 36.8% had both a low-for-age FVII activity level and a positive R353Q variant. Eighty percent of patients with a CBD were found to have relatives with abnormal bleeding symptoms.

CONCLUSION

Congenital FVII deficiency is prevalent among female adolescents experiencing HMB with or without IDA. In addition to VWD, evaluation for this specific factor deficiency should be considered as part of the initial CBD workup. Presence of abnormal bleeding history in the family could also help to predict presence of a CBD.

Diagnosis of Bleeding Disorders in Adolescents Hospitalized for Heavy Menstrual Bleeding

Background  There is scarce information regarding the prevalence and clinical impact of saddle pulmonary embolism (PE) in patients with cancer.

Objectives  This study aimed to assess the prevalence, clinical findings, and short-term outcomes of patients with cancer-related saddle PE including acute symptomatic and unsuspected events.

Patients/Methods  Consecutive patients with cancer-related PE (March 1, 2006–October 31, 2014) were retrospectively reviewed by a chest radiologist to assess PE burden and signs of right ventricular (RV) overload. The clinical outcomes within 30 days were evaluated according to saddle versus nonsaddle PE.

Results  Thirty-six (12%) out of 289 patients with newly diagnosed cancer-related PE presented with saddle PE. Saddle PE was found in 21 cases (58%) with acute symptomatic PE and the remaining 15 cases (42%) were found as unsuspected findings. Patients with saddle PE had more frequently experienced a previous thrombotic event (31 vs. 13%; p  = 0.008), and it occurred more frequently as an acute symptomatic event (58 vs. 39%; p  = 0.025) compared with those with nonsaddle PE. Signs of RV overload including RV/left ventricle ratio ≥1 (22 vs. 4%; p  < 0.001) and interventricular septum displacement (53 vs. 20%; p  < 0.001) were also more common in patients with saddle PE compared with nonsaddle PE. Overall, PE-related mortality, venous thromboembolism recurrence, and major bleeding within 30 days were found to be similar according to saddle versus nonsaddle PE.

Conclusion  Saddle PE is not uncommon in patients with cancer-related PE including in those with unsuspected PE. Similar 30-day outcomes were found according to saddle versus nonsaddle PE in our cohort.

Emergency Department Evaluation of Abnormal Uterine Bleeding in US Children's Hospitals

STUDY OBJECTIVE

To assess initial evaluation patterns of patients presenting to the Emergency Department (ED) with abnormal uterine bleeding (AUB) including differences by race DESIGN: Retrospective multicenter cohort study from October 2015 through September 2020 SETTING: Forty-seven children's hospitals submitting data to the Pediatric Health Information System PARTICIPANTS: Female patients aged 8-21 with an ED encounter with AUB as the primary diagnosis code INTERVENTIONS AND MAIN OUTCOME MEASURES: Proportion of visits with at least 1 laboratory assessment for the evaluation of anemia, iron deficiency, and/or hemostatic disorders RESULTS: We identified 17,759 unique patients with AUB seen in the ED who met inclusion criteria. Median age was 16.3 years (IQR, 14.1-17.8 years). Most encounters (n = 11,576, 65.2%) included evaluation for anemia, but only 6.8% (n = 1,215) included assessment for iron deficiency and 26.2% (n = 4,654) for hemostatic disorders. Black patients accounted for 34.7% (n = 6,155) of AUB encounters yet constituted only 25% of all ED encounters (n = 198,192). Black patients with AUB were less likely to undergo bleeding disorder evaluation (OR = 0.76; 95% CI, 0.69-0.83) but more likely to receive evaluation for sexually transmitted infections (OR = 1.63; 95% CI, 1.48-1.80) compared with White patients, despite controlling for age and concomitant pain.

CONCLUSIONS

In a national cohort of adolescents presenting to the ED with AUB, evaluations for anemia and hemostatic disorders were infrequently performed, and racial differences existed regarding initial assessment. Further studies are needed to understand the factors underlying racial differences in hematologic testing and the impact of this disparity on health outcomes for females with AUB.

Health issues in women and girls affected by haemophilia with a focus on nomenclature, heavy menstrual bleeding, and musculoskeletal issues

Introduction

Women and girls affected by haemophilia, including haemophilia carriers (WGH) are at risk of bleeding symptoms that may go unrecognized, including heavy menstrual bleeding (HMB) and musculoskeletal bleeding. Terminology continues to evolve.

Aim

To describe the current recommendations for nomenclature surrounding WGH, and the current understanding of HMB, iron deficiency, and musculoskeletal complaints in these patients.

Methods

Literature was reviewed and summarized.

Results

With regards to nomenclature, women with factor levels less than 50% should be classified as having haemophilia, while carriers with normal levels should be characterized accordingly to symptomatology. HMB and resultant iron deficiency are common among WGH, have a multitude of downstream effects, and maybe overlooked due to stigma around menstruation. Musculoskeletal bleeding and resultant joint changes are increasingly recognized in this population but do not necessarily correlate with factor levels.

Conclusion

Although progress has been made in the care of WGH, much work remains to further improve their care.

Cryptogenic oozers and bruisers

Bleeding disorders with normal, borderline, or nondiagnostic coagulation tests represent a diagnostic challenge. Disorders of primary hemostasis can be further evaluated by additional platelet function testing modalities, platelet electron microscopy, repeat von Willebrand disease testing, and specialized von Willebrand factor testing beyond the usual initial panel. Secondary hemostasis is further evaluated by coagulation factor assays, and factor XIII assays are used to diagnose disorders of fibrin clot stabilization. Fibrinolytic disorders are particularly difficult to diagnose with current testing options. A significant number of patients remain unclassified after thorough testing; most unclassified patients have a clinically mild bleeding phenotype, and many may have undiagnosed platelet function disorders. High-throughput genetic testing using large gene panels for bleeding disorders may allow diagnosis of a larger number of these patients in the future, but more study is needed. A logical laboratory workup in the context of the clinical setting and with a high level of expertise regarding test interpretation and limitations facilitates a diagnosis for as many patients as possible.