Abnormal vaginal bleeding in women of reproductive age treated with edoxaban or warfarin for venous thromboembolism: a post hoc analysis of the Hokusai-VTE study

Incidence and Impact on Quality of Life of Heavy Menstrual Bleeding in Women on Oral Anticoagulant Therapy

INTRODUCTION

Heavy menstrual bleeding affects up to two thirds of women on oral anticoagulation. The rates of heavy menstrual bleeding, its impact on quality of life and associated risk factors in women attending anticoagulation clinics in South Africa are largely unknown.

MATERIALS AND METHODS

A prospective cohort study was performed over an eight-month period in women on Warfarin (n = 30) and Rivaroxaban (n = 27) for a median [interquartile range] duration of 15.5 [78.0] months attending an anticoagulation clinic in Johannesburg, South Africa. Heavy menstrual bleeding was assessed over one menstrual cycle using the validated pictorial blood loss assessment charts (PBAC) and the menstrual bleeding questionnaire (MBQ).

RESULTS

In this population of predominantly African ethnicity, with a median age of 39 [8] years, 39 (68.4%) women experienced heavy menstrual bleeding, defined as a PBAC score of >100. Median cycle length on anticoagulation and MBQ scores were significantly higher among women with a PBAC score of >100 (p > 0.05). Univariate analysis identified Rivaroxaban as a risk factor for heavy menstrual bleeding (OR 5.03, 95% CI 1.40-18.12). Heavy menstrual bleeding required treatment in 29 (74.4%) women which included management of iron deficiency, anti-fibrinolytics, modification of anticoagulation and hormonal contraception.

CONCLUSION

Heavy menstrual bleeding was associated with a considerable negative impact on quality of life. This was most significant for women on Rivaroxaban as compared to Warfarin. It is essential to monitor and appropriately treat heavy menstrual bleeding in at risk women on anticoagulant treatment.

Effects of antiplatelet therapy on menstrual blood loss in reproductive-aged women: a systematic review

Background

The effects of antiplatelet therapy on menstrual bleeding have not been well characterized.

Objectives

To systematically review the effects of antiplatelet therapy on menstrual bleeding.

Methods

A literature search was performed for studies of reproductive-aged women who received antiplatelet therapy. Characteristics of menstrual bleeding both before and after initiation of antiplatelet therapy and from comparison groups were collected. Two reviewers independently assessed the risk of bias in individual studies.

Results

Thirteen studies with a total of 611 women who received antiplatelet therapy were included. Types of antiplatelet drugs used were aspirin (n = 8), aspirin and/or clopidogrel (n = 2), prasugrel (n = 1), and not specified (n = 2). Risk of bias was assessed at moderate (n = 1), serious (n = 8), critical (n = 2), and no information (n = 2). Three studies reported changes in menstrual blood loss volume. One of these showed no increase during antiplatelet therapy; the other 2 studies suggested that aspirin may increase menstrual blood loss volume. In 3 studies that assessed the duration of menstrual bleeding, up to 13% of women reported an increased duration of menstruation. In 5 studies that reported the intensity of menstrual flow, 13% to 38% of women experienced an increase in the intensity of flow. Five studies reported the prevalence of heavy menstrual bleeding in women who received antiplatelet therapy, with estimates ranging from 7% to 38%.

Conclusion

There is lack of high-quality data on the effects of antiplatelet therapy on menstrual bleeding. Aspirin may increase menstrual blood loss, at least in a minority of women, whereas the effects of P2Y12 inhibitors are unknown.

Abnormal uterine bleeding in anticoagulated patients by drug class: outcomes and management

BACKGROUND

Although abnormal uterine bleeding is a known adverse effect of anticoagulant drugs, true rates have not been widely studied. Society-backed recommendations and guidelines do not yet exist for prevention and management of abnormal uterine bleeding among anticoagulated patients.

OBJECTIVE

This study aimed to describe the incidence of new-onset abnormal uterine bleeding among patients receiving therapeutic anticoagulation by anticoagulant class, and to evaluate gynecologic treatment patterns.

STUDY DESIGN

We conducted an institutional review board-waived retrospective chart review of female patients aged 18 to 55 years and prescribed therapeutic anticoagulants, including vitamin-K antagonists, low-molecular-weight heparins, and direct oral anticoagulants, in an urban hospital network from January 2015 through January 2020. We excluded patients with antecedent abnormal uterine bleeding and menopause. Associations between abnormal uterine bleeding, anticoagulant class, and other covariates were evaluated with Pearson chi-square and analysis-of-variance tests. The primary outcome, abnormal uterine bleeding odds by anticoagulant class, was modeled with logistic regression. Age, antiplatelet therapy, body mass index, and race were included in our multivariable model. Secondary outcomes included emergency department visits and treatment patterns.

RESULTS

Of the 2479 patients who met the inclusion criteria, 645 were diagnosed with abnormal uterine bleeding after initiating therapeutic anticoagulation. After adjusting for age, race, body mass index, and concurrent use of antiplatelet therapy, those receiving all 3 classes of anticoagulants had higher odds of experiencing abnormal uterine bleeding (adjusted odds ratio, 2.63; confidence interval, 1.70-4.08; P<.001), whereas those taking only direct oral anticoagulants had the lowest odds (adjusted odds ratio, 0.70; confidence interval, 0.51-0.97; P=.032), with vitamin-K antagonists as the reference group. Race other than White was associated with higher odds of abnormal uterine bleeding, as was lower age. The most common hormone therapies used among patients with abnormal uterine bleeding were levonorgestrel intrauterine devices (7.6%; 49/645) and oral progestins (7.6%; 49/645). Sixty-eight patients (10.5%; 68/645) had an emergency department visit for abnormal uterine bleeding; 29.5% (190/645) of patients received a blood transfusion; 12.2% (79/645) began any pharmacologic therapy for bleeding; and 18.8% (121/645) underwent any gynecologic procedure.

CONCLUSION

Abnormal uterine bleeding occurs frequently among patients on therapeutic anticoagulation. Incidence in this sample varied considerably by anticoagulant class and race; use of single-agent direct oral anticoagulation carried the lowest risk. Important sequelae such as bleeding-related emergency department visits, blood transfusions, and gynecologic procedures were common. Balancing bleeding and clotting risk in patients on therapeutic anticoagulation requires a nuanced approach and should involve collaborative management between hematologists and gynecologists.

Oral direct thrombin inhibitors or oral factor Xa inhibitors versus conventional anticoagulants for the treatment of pulmonary embolism

BACKGROUND

Pulmonary embolism (PE) is a potentially life-threatening condition in which a clot can migrate from the deep veins, most commonly in the leg, to the lungs. Conventional treatment of PE used unfractionated heparin (UFH), low molecular weight heparin (LMWH), fondaparinux, and vitamin K antagonists (VKAs). Recently, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors. DOACs have characteristics that may be favourable to conventional treatment, including oral administration, a predictable effect, no need for frequent monitoring or re-dosing, and few known drug interactions. This review reports the efficacy and safety of these drugs in the long-term treatment of PE (minimum duration of three months). This is an update of a Cochrane Review first published in 2015.  OBJECTIVES: To assess the efficacy and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of PE.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov trials registers to 2 March 2022. We checked the reference lists of relevant articles for additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which people with a PE confirmed by standard imaging techniques were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with a conventional anticoagulant or compared with each other for the long-term treatment of PE (minimum duration three months).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were recurrent PE, recurrent venous thromboembolism (VTE), and deep vein thrombosis (DVT). Secondary outcomes were all-cause mortality, major bleeding, and health-related quality of life. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified five additional RCTs with 1484 participants for this update. Together with the previously included trials, we have included ten RCTs with a total of 13,073 participants. Two studies investigated an oral DTI (dabigatran) and eight studies investigated oral factor Xa inhibitors (three rivaroxaban, three apixaban, and two edoxaban). The studies were of good methodological quality overall.  Meta-analysis showed no clear difference in the efficacy and safety of oral DTI compared with conventional anticoagulation in preventing recurrent PE (odds ratio (OR) 1.02, 95% confidence interval (CI) 0.50 to 2.04; 2 studies, 1602 participants; moderate-certainty evidence), recurrent VTE (OR 0.93, 95% CI 0.52 to 1.66; 2 studies, 1602 participants; moderate-certainty evidence), DVT (OR 0.79, 95% CI 0.29 to 2.13; 2 studies, 1602 participants; moderate-certainty evidence), and major bleeding (OR 0.50, 95% CI 0.15 to 1.68; 2 studies, 1527 participants; moderate-certainty evidence). We downgraded the certainty of evidence by one level for imprecision due to the low number of events. There was also no clear difference between the oral factor Xa inhibitors and conventional anticoagulation in the prevention of recurrent PE (OR 0.92, 95% CI 0.66 to 1.29; 3 studies, 8186 participants; moderate-certainty evidence), recurrent VTE (OR 0.83, 95% CI 0.66 to 1.03; 8 studies, 11,416 participants; moderate-certainty evidence), DVT (OR 0.77, 95% CI 0.48 to 1.25; 2 studies, 8151 participants; moderate-certainty evidence), all-cause mortality (OR 1.16, 95% CI 0.79 to 1.70; 1 study, 4817 participants; moderate-certainty evidence) and major bleeding (OR 0.71, 95% CI 0.36 to 1.41; 8 studies, 11,447 participants; low-certainty evidence); the heterogeneity for major bleeding was significant (I2 = 79%). We downgraded the certainty of the evidence to moderate and low because of imprecision due to the low number of events and inconsistency due to clinical heterogeneity. None of the included studies measured health-related quality of life.

AUTHORS' CONCLUSIONS

Available evidence shows there is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent PE, recurrent VTE, DVT, all-cause mortality, and major bleeding. The certainty of evidence was moderate or low. Future large clinical trials are required to identify if individual drugs differ in effectiveness and bleeding risk, and to explore effect differences in subgroups, including people with cancer and obesity.

Oral direct thrombin inhibitors or oral factor Xa inhibitors versus conventional anticoagulants for the treatment of deep vein thrombosis

BACKGROUND

Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately one in 1000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors, which have characteristics that may be favourable compared to conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or dose adjustment and few known drug interactions. DOACs are now commonly being used for treating DVT: recent guidelines recommended DOACs over conventional anticoagulants for both DVT and PE treatment. This Cochrane Review was first published in 2015. It was the first systematic review to measure the effectiveness and safety of these drugs in the treatment of DVT. This is an update of the 2015 review.  OBJECTIVES: To assess the effectiveness and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of DVT.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 1 March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which people with a DVT, confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with conventional anticoagulation or compared with each other for the treatment of DVT.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were recurrent venous thromboembolism (VTE), recurrent DVT and PE. Secondary outcomes included all-cause mortality, major bleeding, post-thrombotic syndrome (PTS) and quality of life (QoL). We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified 10 new studies with 2950 participants for this update. In total, we included 21 RCTs involving 30,895 participants. Three studies investigated oral DTIs (two dabigatran and one ximelagatran), 17 investigated oral factor Xa inhibitors (eight rivaroxaban, five apixaban and four edoxaban) and one three-arm trial investigated both a DTI (dabigatran) and factor Xa inhibitor (rivaroxaban). Overall, the studies were of good methodological quality. Meta-analysis comparing DTIs to conventional anticoagulation showed no clear difference in the rate of recurrent VTE (odds ratio (OR) 1.17, 95% confidence interval (CI) 0.83 to 1.65; 3 studies, 5994 participants; moderate-certainty evidence), recurrent DVT (OR 1.11, 95% CI 0.74 to 1.66; 3 studies, 5994 participants; moderate-certainty evidence), fatal PE (OR 1.32, 95% CI 0.29 to 6.02; 3 studies, 5994 participants; moderate-certainty evidence), non-fatal PE (OR 1.29, 95% CI 0.64 to 2.59; 3 studies, 5994 participants; moderate-certainty evidence) or all-cause mortality (OR 0.66, 95% CI 0.41 to 1.08; 1 study, 2489 participants; moderate-certainty evidence). DTIs reduced the rate of major bleeding (OR 0.58, 95% CI 0.38 to 0.89; 3 studies, 5994 participants; high-certainty evidence).   For oral factor Xa inhibitors compared with conventional anticoagulation, meta-analysis demonstrated no clear difference in recurrent VTE (OR 0.85, 95% CI 0.71 to 1.01; 13 studies, 17,505 participants; moderate-certainty evidence), recurrent DVT (OR 0.70, 95% CI 0.49 to 1.01; 9 studies, 16,439 participants; moderate-certainty evidence), fatal PE (OR 1.18, 95% CI 0.69 to 2.02; 6 studies, 15,082 participants; moderate-certainty evidence), non-fatal PE (OR 0.93, 95% CI 0.68 to 1.27; 7 studies, 15,166 participants; moderate-certainty evidence) or all-cause mortality (OR 0.87, 95% CI 0.67 to 1.14; 9 studies, 10,770 participants; moderate-certainty evidence). Meta-analysis showed a reduced rate of major bleeding with oral factor Xa inhibitors compared with conventional anticoagulation (OR 0.63, 95% CI 0.45 to 0.89; 17 studies, 18,066 participants; high-certainty evidence).  AUTHORS' CONCLUSIONS: The current review suggests that DOACs may be superior to conventional therapy in terms of safety (major bleeding), and are probably equivalent in terms of efficacy. There is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent VTE, recurrent DVT, pulmonary embolism and all-cause mortality. DOACs reduced the rate of major bleeding compared to conventional anticoagulation. The certainty of evidence was moderate or high.

How do anticoagulants impact menstrual bleeding and quality of life? - The PERIOD study

Background

There is increasing recognition that menstruating women prescribed anticoagulants experience heavy menstrual bleeding.

Objectives

The aim of this study is to report the extent of bleeding in menstruating women after commencing anticoagulants and the impact it has on their quality of life.

Methods

Women aged 18 to 50, initiated on anticoagulant therapy, were approached to take part in the study. In parallel, a control group of women was also recruited. Women were asked to complete the menstrual bleeding questionnaire and a pictorial blood assessment chart (PBAC) during their next 2 menstrual cycles. Differences between the control and anticoagulated group were compared. Significance was considered at < .05. Ethics committee approval: REC reference: 19/SW/0211.

Results

Fifty-seven women in the anticoagulation and 109 women in the control group returned their questionnaires. Women in the anticoagulated group reported an increase in the median length of their menstrual cycle from 5 to 6 days after commencing anticoagulation, compared to 5 days for women in the control group (P < .05). Anticoagulated women reported significantly higher PBAC scores as compared to the control group (P < .05), with two-thirds of women in the anticoagulation group reporting heavy menstrual bleeding. Women in the anticoagulation group reported worsening quality of life scores following the initiation of anticoagulation, compared with women in the control group (P < .05).

Conclusion

Heavy menstrual bleeding occurred in two-thirds of women commencing anticoagulants, who completed a PBAC, which had negative impact on their quality of life. Clinicians commencing anticoagulation therapy should be mindful of this, and recognized measures should be taken to help minimize this problem for menstruating individuals.

Anticoagulant therapy for women: implications for menstruation, pregnancy, and lactation

Estrogen exposure, in the setting of pregnancy, the postpartum state, combined hormonal contraceptives (CHCs), or hormone therapy use, has been clearly associated with increased rates of venous thromboembolism (VTE). Although recurrence rates are low in these settings, up to 70% of anticoagulated menstruating individuals experience abnormal or heavy menstrual bleeding (HMB), which commonly results in iron deficiency with or without anemia. Patients taking rivaroxaban appear to experience higher rates of HMB compared with those on apixaban, dabigatran, or warfarin. HMB can often be diagnosed in a single visit with a good menstrual history assessing for factors with a known association with increased or heavy bleeding, such as changing pads or tampons more often than every 2 hours, clots larger than a quarter, and iron deficiency (ferritin <50  ng/mL). HMB can be managed with hormonal therapies, including those associated with VTE risk, such as CHCs and depot-medroxyprogesterone acetate (DMPA). In many cases, continuing CHCs or DMPA while a patient is therapeutically anticoagulated is reasonable, so long as the therapy is discontinued before anticoagulation is stopped. Modification of the anticoagulation regimen, such as decreasing to a prophylactic dose in the acute treatment period, is not currently recommended. For patients who are currently pregnant, low-molecular-weight heparin (LMWH) is still standard of care during pregnancy; routine monitoring of anti-factor Xa levels is not currently recommended. Warfarin or LMWH may be considered in the postpartum setting, but direct-acting oral anticoagulants are currently not recommended for lactating patients.

Incidence and impact of anticoagulation-associated abnormal menstrual bleeding in women after venous thromboembolism

Preliminary data and clinical experience have suggested an increased risk of abnormal uterine bleeding (AUB) in women of reproductive age treated with anticoagulants, but solid data are lacking. The TEAM-VTE study was an international multicenter prospective cohort study in women aged 18 to 50 years diagnosed with acute venous thromboembolism (VTE). Menstrual blood loss was measured by pictorial blood loss assessment charts at baseline for the last menstrual cycle before VTE diagnosis and prospectively for each cycle during 3 to 6 months of follow-up. AUB was defined as an increased score on the pictorial blood loss assessment chart (>100 or >150) or self-reported AUB. AUB-related quality of life (QoL) was assessed at baseline and the end of follow-up using the Menstrual Bleeding Questionnaire. The study was terminated early because of slow recruitment attributable to the COVID-19 pandemic. Of the 98 women, 65 (66%) met at least one of the 3 definitions of AUB during follow-up (95% confidence interval [CI], 57%-75%). AUB occurred in 60% of women (36 of 60) without AUB before VTE diagnosis (new-onset AUB; 95% CI, 47%-71%). Overall, QoL decreased over time, with a mean Menstrual Bleeding Questionnaire score increase of 5.1 points (95% CI, 2.2-7.9), but this decrease in QoL was observed only among women with new-onset AUB. To conclude, 2 of every 3 women who start anticoagulation for acute VTE experience AUB, with a considerable negative impact on QoL. These findings should be a call to action to increase awareness and provide evidence-based strategies to prevent and treat AUB in this setting. This was an academic study registered at www.clinicaltrials.gov as #NCT04748393; no funding was received.

Bleeding Issues in Women Under Oral Anticoagulation

In premenopausal women treatment with direct oral anticoagulants (DOACs) can be associated with an increased risk of heavy menstrual bleeding (HMB) compared with vitamin K antagonists. These findings come from retrospective or prospective single-center studies and post hoc analysis of regulatory studies in which HMB was not a predefined safety outcome. In most of these publications, there is a lack of information about the use of different contraceptive methods which can influence HMB. Another limitation is the various definitions of HMB, which makes comparison between studies regarding the incidences of HMB difficult.

Therefore, prospective studies are urgently needed to investigate the severity and duration of unaffected menstrual bleeding under oral anticoagulation independently of oral contraceptives or intrauterine devices. An ongoing multicenter German registry is aiming to compare the incidence of unaffected HMB in consecutive women of reproductive age (18–50 years) treated with different DOACs because of venous thromboembolism.

When HMB occurs during oral anticoagulation, management includes interruption or dose reduction of anticoagulation with the danger of recurrent venous thrombosis, switch to another oral anticoagulant, or additional use of the antifibrinolytic agent tranexamic acid with the potential risk of thrombosis. Concomitant use of either oral hormonal contraceptive therapy or hormone-releasing intrauterine systems can also reduce HMB.

Optimal follow-up after acute pulmonary embolism: a position paper of the European Society of Cardiology Working Group on Pulmonary Circulation and Right Ventricular Function, in collaboration with the European Society of Cardiology Working Group on Atherosclerosis and Vascular Biology, endorsed by the European Respiratory Society

This position paper provides a comprehensive guide for optimal follow-up of patients with acute pulmonary embolism (PE), covering multiple relevant aspects of patient counselling. It serves as a practical guide to treating patients with acute PE complementary to the formal 2019 European Society of Cardiology guidelines developed with the European Respiratory Society. We propose a holistic approach considering the whole spectrum of serious adverse events that patients with acute PE may encounter on the short and long run. We underline the relevance of assessment of modifiable risk factors for bleeding, of acquired thrombophilia and limited cancer screening (unprovoked PE) as well as a dedicated surveillance for the potential development of chronic thromboembolic pulmonary hypertension as part of routine practice; routine testing for genetic thrombophilia should be avoided. We advocate the use of outcome measures for functional outcome and quality of life to quantify the impact of the PE diagnosis and identify patients with the post-PE syndrome early. Counselling patients on maintaining a healthy lifestyle mitigates the risk of the post-PE syndrome and improves cardiovascular prognosis. Therefore, we consider it important to discuss when and how to resume sporting activities soon after diagnosing PE. Additional patient-relevant topics that require Focused counselling are travel and birth control.

Do women with venous thromboembolism bleed more than men during anticoagulation? Data from the real-life, prospective START-Register

Background:

Venous thromboembolism (VTE) is a frequent and serious disease that requires immediate and long-term anticoagulant treatment, which is inevitably associated with a risk of bleeding complications. Some studies, though not all, reported a higher risk of bleeding in female patients treated with either old anticoagulants [vitamin k antagonists (VKAs)] or recent anticoagulants [direct oral anticoagulants (DOACs)]. Furthermore, analyses of clinical trials reported an abnormal vaginal bleeding in women of reproductive age treated with DOACs. This study aimed at comparing the risk of bleeding in an inception cohort of VTE women and men included in a prospective observational registry.

Methods:

Baseline characteristics and bleeding events occurring during anticoagulation in patients of both sexes, included in the START-Register after a first VTE, were analyzed.

Results:

In all, 1298 women were compared with 1290 men. Women were older and more often had renal diseases; their index events were often provoked (often by hormonal contraception and pregnancy), and more frequently presented as isolated pulmonary embolism (PE). The rate of bleeding was similar in women (2.9% patient-years) and men (2.1% patient-years), though it was higher when uterine bleeds were included (3.5% patient-years, p = 0.0141). More bleeds occurred in VKA- than DOAC-treated patients (6.4% versus 2.6%, respectively; p = 0.0013). At multivariate analysis, age ⩾ 75 years was associated with higher prevalence of bleeds.

Conclusion:

The occurrence of bleeding was not different between women and men during anticoagulation after VTE. Only after inclusion of vaginal/uterine bleeds, the rate of bleeding was higher in women. The incidence of bleeding was higher in women treated with VKAs.

Plain Language Summary

Reproductive issues in women on direct oral anticoagulants

Direct oral anticoagulants (DOACs) are replacing warfarin and other vitamin K antagonists for a wide range of indications. Advantages of DOAC therapy are fewer food and drug interactions and fixed dosing without routine laboratory monitoring, making DOACs the perfect choice especially for younger patients, in whom the main indication for anticoagulation is prevention and treatment of venous thromboembolism (VTE). Although DOACs are safer and much more convenient than other anticoagulant alternatives, their profile may have drawbacks, especially for younger female patients in whom reproductive issues need special considerations. These may include the issue of heavy menstrual bleeding (HMB) during anticoagulant therapy, the embryotoxicity risk from inadvertent DOAC exposure during pregnancy, and the prevention or planning of pregnancies during DOAC therapy. This review summarizes the most relevant evidence in this increasingly important field of women's health.

Outpatient treatment of emergency department patients diagnosed with venous thromboembolism

Venous thromboembolism (VTE) includes the diagnosis of either deep venous thrombosis (DVT) and/or pulmonary embolism (PE). This review discusses an evidence-based approach to the outpatient treatment of VTE in the emergency care setting. Main findings: The majority of patients diagnosed with VTE in the acute care setting are at low risk for an adverse event. Outpatient treatment for patients deemed low-risk by validated clinical decision tools leads to safe, efficacious, patient-centered, and cost-effective care. From a patient perspective, outpatient treatment of VTE can been simplified by the use of direct oral anticoagulant (DOACs) medications, and is supported by clinical trial evidence, and clinical practice guidelines from international societies. Outpatient treatment of patients with DVT has been more widely accepted as a best practice, while adoption of outpatient treatment of low-risk patients with acute PE has lagged. Many acute care clinicians remain wary of discharging patients with PE, concerned about drug access, adherence, and follow-up. Patients with VTE should be risk stratified identically as emerging evidence has demonstrated efficacy and safety in the interdependence of acute care protocols for the outpatient treatment of low-risk DVT and PE. Clinicians who practice in the acute care setting should be comfortable with risk stratification, anticoagulation, and discharge of low-risk VTE.

Comparative Risk Assessment of Severe Uterine Bleeding Following Exposure to Direct Oral Anticoagulants: A Network Study Across Four Observational Databases in the USA

BACKGROUND

Antithrombotic therapies are associated with an increased bleeding risk. Abnormal uterine bleeding data have been reported in clinical trials of patients with venous thromboembolism (VTE), but data are limited for patients with atrial fibrillation (AF).

OBJECTIVE

Using real-world data from four US healthcare databases (October 2010 to December 2018), we compared the occurrence of severe uterine bleeding among women newly exposed to rivaroxaban, apixaban, dabigatran, and warfarin stratified by indication.

METHODS

To reduce potential confounding, patients in comparative cohorts were matched on propensity scores. Treatment effect estimates were generated using Cox proportional hazard models for each indication, in each database, and only for pairwise comparisons that met a priori study diagnostics. If estimates were homogeneous (I2 < 40%), a meta-analysis across databases was performed and pooled hazard ratios reported.

RESULTS

Data from 363,919 women newly exposed to a direct oral anticoagulant or warfarin with a prior diagnosis of AF (60.8%) or VTE (39.2%) were analyzed. Overall incidence of severe uterine bleeding was low in the populations exposed to direct oral anticoagulants, although relatively higher in the younger VTE population vs the AF population (unadjusted incidence rates: 2.8-33.7 vs 1.9-10.0 events/1000 person-years). In the propensity score-matched AF population, a suggestive, moderately increased risk of severe uterine bleeding was observed for rivaroxaban relative to warfarin [hazard ratios and 95% confidence intervals from 0.83 (0.27-2.48) to 2.84 (1.32-6.23) across databases with significant heterogeneity], apixaban [pooled hazard ratio 1.45 (0.91-2.28)], and dabigatran [2.12 (1.01-4.43)], which were sensitive to the time-at-risk period. In the propensity score-matched VTE population, a consistent increased risk of severe uterine bleeding was observed for rivaroxaban relative to warfarin [2.03 (1.19-3.27)] and apixaban [2.25 (1.45-3.41)], which were insensitive to the time-at-risk period.

CONCLUSIONS

For women who need antithrombotic therapy, personalized management strategies with careful evaluation of benefits and risks are required. CLINICALTRIALS.

GOV REGISTRATION

NCT04394234; registered in May 2020.

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.

Management of heavy menstrual bleeding on anticoagulation

Heavy menstrual bleeding (HMB) is a common complication of anticoagulation, affecting ∼70% of menstruating women receiving oral anticoagulants. The risk of HMB is lower with apixaban and/or dabigatran than with rivaroxaban. HMB can result in iron deficiency with or without anemia, increased need for medical interventions, decreased quality of life, and missed school/work. Mainstays of treatment include hormone therapies such as the levonorgestrel intrauterine system, subdermal implant, and other progesterone-based therapies, which can result in decreased blood loss and, in some cases, amenorrhea. Combined hormone therapies can be used while patients continue receiving anticoagulation and are also highly effective for decreasing menstrual blood loss. Rarely, procedure-based interventions such as endometrial ablation may be required. Patients should be evaluated for iron deficiency and anemia and offered supportive therapies as needed. Abbreviating the course of anticoagulation or skipping doses can increase the risk of recurrent venous thromboembolism by as much as fivefold, but switching oral anticoagulants may be considered. Awareness of HMB and careful history taking at each visit are crucial to avoid a missed diagnosis.

How I assess and manage the risk of bleeding in patients treated for venous thromboembolism

For patients with venous thromboembolism (VTE), prediction of bleeding is relevant throughout the course of treatment, although the means and goal of this prediction differ between the subsequent stages of treatment: treatment initiation, hospital discharge, 3-month follow-up, and long-term follow-up. Even in the absence of fully established risk prediction schemes and outcome studies using a prediction scheme for treatment decisions, the present evidence supports screening for and targeting of modifiable risk factors for major bleeding, as well as the application of decision rules to identify patients at low risk of bleeding complications, in whom long-term anticoagulant treatment is likely safe. Moving forward, prediction tools need to be incorporated in well-designed randomized controlled trials aiming to establish optimal treatment duration in patients at high risk of recurrent VTE. Moreover, the benefit of their longitudinal assessment rather than application as stand-alone baseline assessments should be studied, because changes in bleeding risk over time likely constitute the best predictor of major bleeding. We provide the state-of-the-art of assessing and managing bleeding risk in patients with acute VTE and highlight a practical approach for daily practice illustrated by 2 case scenarios.

Descriptive study of the general practitioners' perception of direct oral anticoagulants and the risk of genital bleeding in women of childbearing age

AIM OF THE STUDY AND PATIENTS

Direct oral anticoagulants (DOA) tend to replace antivitamins K (VKA). The incidence of major and minor hemorrhages is higher in women, a difference potentially linked to genital hemorrhages. The objective is to assess the practices and perception of general practitioners of the use of oral anticoagulant therapy in women of childbearing age.

MATERIALS AND METHODS

Descriptive, observational, transversal and monocentric study. An 11-items questionnaire was sent to 900 randomized general practitioners, assessing the type of patient, the type of anticoagulant prescribed, the management of genital bleeding, and the assessment of the quality of life of anticoagulated patients.

RESULTS

DOA were the most prescribed anticoagulants. Genital hemorrhage was the second leading cause of minor hemorrhage. Most doctors (60.6%) believed they were due to VKAs. 25% reported an alteration in the quality of life of patients following these genital hemorrhages and 47.5% addressed this subject in consultation.

CONCLUSION

Our study suggests that, according to the general practitioners interviewed, genital hemorrhage is more frequent on VKA than on DOA in women of reproductive age, which is contradictory with the data in the literature. The probably taboo subject is rarely mentioned in consultation and is responsible for a deterioration in the quality of life in these young patients. No recommendation exists on the management of this type of genital hemorrhage in these women. An algorithm is proposed for their management.

Acute treatment of venous thromboembolism

All patients with venous thromboembolism (VTE) should receive anticoagulant treatment in the absence of absolute contraindications. Initial anticoagulant treatment is crucial for reducing mortality, preventing early recurrences, and improving long-term outcome. Treatment and patient disposition should be tailored to the severity of clinical presentation, to comorbidities, and to the potential to receive appropriate care in the outpatient setting. Direct oral anticoagulants (DOACs) used in fixed doses without laboratory monitoring are the agents of choice for the treatment of acute VTE in the majority of patients. In comparison with conventional anticoagulation (parenteral anticoagulants followed by vitamin K antagonists), these agents showed improved safety (relative risk [RR] of major bleeding, 0.61; 95% confidence interval [CI], 0.45-0.83) with a similar risk of recurrence (RR, 0.90; 95% CI, 0.77-1.06). Vitamin K antagonists or low molecular weight heparins are still alternatives to DOACs for the treatment of VTE in specific patient categories such as those with severe renal failure or antiphospholipid syndrome, or cancer, respectively. In addition to therapeutic anticoagulation, probably less than 10% of patients require reperfusion by thrombolysis or interventional treatments; those patients are hemodynamically unstable with acute pulmonary embolism, and a minority of them have proximal limb-threatening deep vein thrombosis (DVT). The choice of treatment should be driven by the combination of evidence from clinical trials and by local expertise. The majority of patients with acute DVT and a proportion of selected hemodynamically stable patients with acute pulmonary embolism can be safely managed as outpatients.

Effectiveness and Safety of Apixaban for Treatment of Venous Thromboembolism in Daily Practice

Introduction  Phase 3 trials have shown comparable efficacy of direct oral anticoagulants (DOACs) and vitamin K antagonists in patients with acute venous thromboembolism (VTE), with less major bleeding events in patients randomized to DOAC treatment. With DOACs being increasingly used in clinical practice, evaluation of the DOACs in daily practice-based conditions is needed to confirm their safety and effectiveness. The aim of this study is to evaluate the effectiveness and safety of apixaban in VTE patients in daily practice. Methods  In this retrospective cohort study, consecutive patients diagnosed with VTE in two Dutch hospitals (Leiden University Medical Center, Leiden and Haga Teaching Hospital, The Hague) were identified based on administrative codes. We assessed recurrent VTE, major bleeding and mortality during a 3-month follow-up period in those treated with apixaban. Results  Of 671 consecutive VTE patients treated with apixaban, 371 presented with acute pulmonary embolism (PE) and 300 patients with deep-vein thrombosis. During 3 months treatment, 2 patients had a recurrent VTE (0.3%; 95% confidence interval [CI]: 0.08-1.1), 12 patients had major bleeding (1.8%; 95% CI: 1.0-3.2), and 11 patients died (1.6%; 95% CI: 0.9-2.9), of which one patient with recurrent PE and one because of a intracerebral bleeding. Conclusion  In this daily practice-based cohort, apixaban yielded a low incidence of recurrent VTE, comparable to the phase 3 AMPLIFY study patients. The incidence of major bleeding was higher than in the AMPLIFY-study patients, reflecting the importance of daily practice evaluation and the fact that results from phase III clinical studies cannot be directly extrapolated toward daily practice.

Increasing use of anticoagulants in Germany and its impact on hospitalization rates for genitourinary bleeding

The aim of the study was to compare nationwide time trends of prescribed oral anticoagulants (OAC) with the time trend of genitourinary bleedings (GUB) in Germany from 2005 through 2016. The annual numbers of hospitalized patients with GUB coded as "hematuria", "excessive, frequent and irregular menstruation", "postmenopausal bleeding" or "abnormal uterine and vaginal bleeding" were extracted from the nationwide hospitalization file by the Federal Bureau of Statistics. Hospitalization rates were age-standardized using the German standard population 2011. Defined daily doses (DDD) of prescribed anticoagulants among outpatients for the same calendar period were extracted from reports of the statutory health insurance drug information system. Based on DDD, drug treatment rates per 100,000 person years (py) were calculated. From 2005 to 2016, annual OAC treatment rates per 100,000 py increased by 135.8% (from 901.4 to 2125.9). Until 2011 direct oral anticoagulants (DOAC) represented less than 0.1% of all OAC, but 49.9% in 2016. In the same period age-standardized rates of hospitalizations for hematuria increased continuously (annual change of 1.03 (95% CI 0.94-1.11) per 100,000 py), that of "postmenopausal" (- 1.93; 95% CI - 2.38 to - 1.49) or "excessive, frequent and irregular menstruation" decreased (- 1.25; 95% CI -1.62 to - 0.87) and that of "abnormal uterine and vaginal haemorrhage" remained almost unchanged. From all cases with hematuria 5.3% received at least 1 red blood cell concentrate (RBC) in 2005 and 8.2% in 2016 whereas all cases with the other three types of bleeding counted for 1.9% in 2005 and 3.8% in 2016. The time trends for GUB in all subgroups changed steadily and showed no effect of the disproportional increase of DAOCs until 2011. Our ecologic nationwide comparison of OAC treatment rates in outpatients and hospitalization rates for GUBs revealed that despite increasing OAC treatment rates from 2011 to 2016 the hospitalization rates for GUB showed steady annual changes unaffected by the increasing prescription rates of DOACs since 2011.

Optimal management of hormonal contraceptives after an episode of venous thromboembolism

Optimal management of hormonal contraception in patients with venous thromboembolism (VTE) requires an individualized approach considering its potential benefits and complications during and after anticoagulant treatment. Potential benefits include prevention of pregnancy and mitigation of menstrual bleeding that is often worsened after start of anticoagulation therapy. Current evidence suggests that patients may opt for a continuation of (all forms of) hormonal contraception during anticoagulant treatment, provided that they are adequately informed by the treating physicians. Combined oral contraceptives should be stopped before anticoagulant therapy may be discontinued, preferably after the second last menstrual cycle of the intended anticoagulant treatment period. If hormonal contraceptive treatment needs to be initiated in patients with a history of VTE, oral prostagen-only therapy or intra-uterine devices are to be preferred: this may be independent of the anticoagulation status and in light of a negligible risk of (recurrent) VTE associated with their use.

DOACS in women: pros and cons

The recent approval of direct-acting oral anticoagulants (DOAC) for long-term anticoagulation in atrial fibrillation and venous thromboembolism resulted in a rapid implementation of these new drugs into daily care. Although DOAC dosing is similar for women and men and, overall, results in comparable outcomes, sex specific issues need to be considered. This review will discuss DOAC topics specifically related to women's health, including the risks and benefits of DOAC treatment for women, the issue of abnormal uterine bleeding from DOAC and the risk and management of DOAC exposure in pregnancy.

The current place of direct oral anticoagulants in the prevention/treatment of venous thromboembolism

Venous thromboembolism (VTE; includes deep venous thrombosis, DVT, and pulmonary embolism, PE) represents the third most common acute cardiovascular syndrome. Contemporary VTE management comprises primary prevention in high-risk patients, treatment of established VTE, and prevention of its recurrence (secondary prevention). Anticoagulants are the basis of VTE pharmacological prophylaxis and treatment. For several decades, parenteral (heparin and low-molecular-weight heparins, LMWHs) and oral anticoagulants (vitamin K antagonists, VKAs) have been the cornerstone of VTE prevention/treatment. The introduction of direct oral anticoagulants (DOACs: thrombin inhibitor dabigatran and Xa inhibitors rivaroxaban, apixaban, edoxaban, and betrixaban) markedly improved the management of VTE by overcoming many disadvantages of conventional anticoagulants. For primary VTE prevention in patients after total hip/knee arthroplasty, rivaroxaban, apixaban, and dabigatran are preferred over LMWHs, due to comparable efficacy and safety, but favourable acceptability (avoided everyday injections). In other high-risk populations (other surgical patients, acutely ill medical patients), LMWHs are still the recommended option. Betrixaban is currently the only DOAC approved for VTE prophylaxis in medically ill patients during and after hospitalization. For acute VTE treatment and secondary prevention, DOACs (rivaroxaban, apixaban, edoxaban, and dabigatran) are recommended as the first-line therapy in the general population. DOACs proved to be similarly effective but safer than VKAs. In some specific populations, DOACs also seem to be advantageous over conventional treatment (patients with renal impairment, elderly, long-term secondary prevention in cancer patients). Currently, there is no data from randomized head-to-head comparative studies between the DOAC classes or representatives so the choice is made mainly according to patient characteristics and pharmacokinetic properties of the drug.

Susceptibility to adverse drug reactions

The pharmacological effects of a drug depend on its concentration at the site of action, and therefore on the concentration in blood and on the dose. The relationship between the concentration or dose and the corresponding effect can usually be represented mathematically as a rectangular hyperbola; when effect is plotted against log concentration or log dose, the curve is sigmoidal. Inevitably, the effect size and the doses causing benefit and harm will differ among individuals, since they are biological phenomena: some individuals are more likely than others to suffer harm at any given dose. Some harmful effects can occur at much lower doses than those used in therapeutics; that is, the log dose-response curve for harm lies far to the left of the log dose-response curve for benefit. Those who suffer such reactions are hypersusceptible. When the dose-response curves for harm and therapeutic effect are in the same range, dose cannot separate the harmful effects from the therapeutic effects, and adverse reactions are collateral. Toxic effects occur when harmful doses are above the doses needed for benefit. In this review we consider factors that influence a subject's susceptibility to adverse drug reactions. Determinants of susceptibility include Immunological, Genetic, demographic (Age and Sex), Physiological and Exogenous factors (drug-drug interactions, for example), and Diseases and disorders such as renal failure, giving the mnemonic I GASPED. Some susceptibility factors are discrete (for example, all-or-none) and some are continuous; susceptibility can therefore be discrete or continuous; and the factors can interact to determine a person's overall susceptibility to harm.

Sex matters: Practice 5P's when treating young women with venous thromboembolism

Sex matters when it comes to venous thromboembolism (VTE). We defined 5P's - period, pill, prognosis, pregnancy, and postthrombotic syndrome - that should be discussed with young women with VTE. Menstrual blood loss (Period) can be aggravated by anticoagulant therapy. This seems particularly true for direct oral anticoagulants. Abnormal uterine bleeding can be managed by hormonal therapy, tranexamic acid, or modification of treatment. The use of combined oral contraceptives (Pill) is a risk factor for VTE. The magnitude of the risk depends on progestagen types and estrogen doses used. In women using therapeutic anticoagulation, concomitant hormonal therapy does not increase the risk of recurrent VTE. Levonorgestrel-releasing intrauterine devices and low-dose progestin-only pills do not increase the risk of VTE. In young women VTE is often provoked by transient hormonal risk factors that affects prognosis. Sex is incorporated as predictor in recurrent VTE risk assessment models. However, current guidelines do not propose using these to guide treatment duration. Pregnancy increases the risk of VTE by 4-fold to 5-fold. Thrombophilia and obstetric risk factors further increase the risk of pregnancy-related VTE. In women with a history of VTE, the risk of recurrence during pregnancy or post partum appears to be influenced by risk factors present during the first VTE. In most women with a history of VTE, antepartum and postpartum thromboprophylaxis with low-molecular-weight heparin is indicated. Women generally are affected by VTE at a younger age then men, and they have to deal with long-term complications (Post-thrombotic syndrome) of deep vein thrombosis early in life.

Abnormal vaginal bleeding in women of reproductive age treated with edoxaban or warfarin for venous thromboembolism: a post hoc analysis of the Hokusai-VTE study

Objective

To investigate the characteristics and outcome of abnormal vaginal bleeding in women receiving edoxaban or warfarin for treatment of venous thromboembolism (VTE).

Design and setting

Post hoc analysis of the Hokusai‐VTE study, a multicentre, randomised, double‐blind trial comparing edoxaban with warfarin for acute symptomatic VTE.

Population

Women below 50 years receiving edoxaban or warfarin for treatment of VTE.

Methods

We collected data on diagnostic measures, treatment, and clinical outcome of abnormal vaginal bleeding events.

Main outcome measures

Occurrence of major and clinically relevant nonmajor (CRNM) abnormal vaginal bleeding events.

Results

In all, 628 women aged under 50 years were treated with edoxaban and 665 with warfarin. The rate of abnormal vaginal bleeding was 15/100 person‐years (py) (95% CI 11–19) in women receiving edoxaban and 9/100 py (95% CI 6–12) in the warfarin group (hazard ratio: 1.7, 95% CI 1.1–2.5). Major abnormal vaginal bleeding occurred in eight (1.3%) women on edoxaban and in three (0.9%) women receiving warfarin [odds ratio (OR) 2.8; 95% CI 0.8–10.8], and CRNM abnormal vaginal bleeding occurred in 53 (8.4%) women treated with edoxaban and in 37 (5.6%) on warfarin therapy (OR 1.6, 95% CI 1.0–2.4). Over 85% of all vaginal bleeds were characterised by heavy menstrual bleeding. Major bleeds frequently required treatment, and in more than 75% of patients anticoagulant therapy was adjusted. The severity of clinical presentation and course of major and CRNM bleeds was mild in most patients.

Conclusions

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin. Reassuringly, most events could be managed conservatively and had a mild outcome.

Tweetable abstract

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin.

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin.