Racial and ethnic differences in the risk of postpartum venous thromboembolism: a population-based, case-control study

Racial and ethnic disparities in eligibility for postpartum venous thromboembolism prophylaxis in the United States

BACKGROUND

Postpartum venous thromboembolism (VTE) incidence differs by race and ethnicity in the United States. However, it is unclear whether the eligibility criteria for postpartum VTE prophylaxis mirror this disparity.

OBJECTIVE

To characterize the prevalence of risk factors and eligibility for postpartum VTE prophylaxis, among US Birthing people, stratified by race and ethnicity.

METHODS

We analyzed the National Inpatient Sample from October 2015 to December 2019, using diagnosis and procedure codes to identify postpartum individuals and their VTE risk factors. We compared proportion of delivery hospitalizations meeting eligibility for thromboprophylaxis stratified by race or ethnicity, according to American College of Gynecology and Obstetrics, American College of Chest Physicians, Royal College of Obstetricians and Gynecologists (RCOG), and American Society for Hematology guidelines.

RESULTS

Among a national estimate of 14 967 861 delivery hospitalizations in the United States, the proportion of individuals eligible for thromboprophylaxis using the RCOG, American College of Chest Physicians, American College of Gynecology and Obstetrics, and American Society for Hematology guidelines were 32.9%, 8.0%, 0.2%, and 0.2%, respectively. Using the RCOG criteria, non-Hispanic Black individuals had the highest proportion of thromboprophylaxis eligibility (39.7%), whereas it was lowest among Hispanic individuals (30.8%). Racial disparities in thromboprophylaxis eligibility were driven by differences in clinical risk factors (38.8% non-Hispanic Black population vs 30.5% Hispanic population) and cesarean section rates (35.9% vs 32.2%), rather than history of VTE (0.3% vs 0.1%), inherited thrombophilia (0.2% vs 0.2%), or sickle cell disease (0.4% vs <0.1%).

CONCLUSION

Non-Hispanic Black individuals were most likely to qualify for postpartum thromboprophylaxis, attributable to clinical risk factors rather than inherited risk factors. An urgent need exists to better understand ethno-racial disparities in thromboprophylaxis use and to equitably address modifiable risk factors for postpartum VTE.

Hypertensive Disorders of Pregnancy and Pre-Pregnancy Hypertension with Subsequent Incident Venous Thromboembolic Events

Hypertensive disorders of pregnancy (HDP) and pre-pregnancy hypertension contribute to maternal morbidity and mortality. We examined the association of HDP and pre-pregnancy hypertension with subsequent venous thromboembolic (VTE) events. The retrospective cohort study included 444,859 women with ≥1 live, singleton birth in South Carolina (2004-2016). Hospital and emergency department visit and death certificate data defined incident VTE, HDP, and pre-pregnancy hypertension. Birth certificate data also defined the exposures. Adjusted Cox proportional hazards methods modeled VTE events risk. Of the cohort, 2.6% of women had pre-pregnancy hypertension, 5.8% had HDP, 2.8% had both pre-pregnancy hypertension and HDP (both conditions), and 88.8% had neither condition. The risk of incident VTE events within one year of delivery was higher in women with HDP (hazard ratio [HR] = 1.62, 95% confidence interval [CI]: 1.15-2.29) and both conditions (HR = 2.32, 95% CI: 1.60-3.35) compared to those with neither condition as was the risk within five years for women with HDP (HR = 1.35, 95% CI: 1.13-1.60) and for women with both conditions (HR = 1.82, 95% CI: 1.50-2.20). One- and five-year risks did not differ in women with pre-pregnancy hypertension compared to women with neither condition. Compared to non-Hispanic White (NHW) women with neither condition, the incident VTE event risk was elevated within five years of delivery for NHW (HR = 1.29, 95% CI: 1.02-1.63; HR = 1.59, 95% CI: 1.16-2.17) and non-Hispanic Black (NHB; HR = 1.51, 95% CI: 1.16-2.96; HR = 2.08, 95% CI: 1.62-2.66) women with HDP and with both conditions, respectively, and for NHB women with pre-pregnancy hypertension (HR = 1.50, 95% CI: 1.09-2.07). VTE event risk was highest in women with HDP, and the event rates were higher in NHB women than in NHW women in the same exposure group.

Development and validation of a facile rapid assessment scale for perinatal venous thromboembolism in puerperium in Chinese women

BACKGROUND

It is still urgent and challenge to develop a simple risk assessment scale for venous thromboembolism (VTE) in puerperium in Chinese women.

METHODS

The study, a retrospective case-control study, was conducted in 12 hospitals in different cities in China. A total of 1152 pregnant women were selected, including 384 cases with VTE and 768 cases without VTE. A logistic regression method was conducted to determine the risk factors of VTE.

RESULTS

Age, BMI before delivery, gestational diabetes mellitus, family history (thrombosis, diabetes, cardiovascular disease), and assisted reproductive technology were independent risk factors (P<0.05). The difference between the high-risk group and the low-risk group was statistically significant(P<0.001) with a sensitivity of 0.578, specificity of 0.756, Yuden index o.334, and area under the ROC curve of 0.878.

CONCLUSIONS

The age (≥ 35 years), BMI before delivery (≥ 30 kg/m2), gestational diabetes mellitus, family history of related diseases and assisted reproductive technology are more likely to cause VTE after full-time delivery. The simple and rapid assessment scale of VTE in women after full-term delivery has perfect discrimination (P < 0.001), which can be applied to predict the risk of VTE in Chinese full-term postpartum women.

Venous Thromboembolism in Pregnancy: Challenges and Solutions

Venous thromboembolism (VTE) is a serious medical condition that can lead to severe morbidity and mortality, making it a significant public health concern. VTE is a multifactorial condition that results from the interaction of genetic, acquired, and environmental factors. Physiological changes during pregnancy increase the risk of VTE as they express Virchow's triad (increased coagulation factors, decreased fibrinolysis, trauma, and venous stasis). Moreover, pregnancy-related risk factors, such as advanced maternal age, obesity, multiple gestations, and cesarean delivery, further increase the risk of VTE. Managing VTE in pregnancy is challenging due to the complexity of balancing the risks and benefits of anticoagulant therapy for both the mother and the fetus. A multidisciplinary approach involving obstetricians, hematologists, and neonatologists, is necessary to ensure optimal outcomes for both the mother and baby. This review aims to discuss the current challenges associated with VTE in pregnancy and identify potential solutions for improving outcomes for pregnant women at risk for VTE.

Baseline rotational thromboelastometry (ROTEM) values in a healthy, diverse obstetric population and parameter changes by pregnancy-induced comorbidities

Background

Point-of-care testing provides a representation of the patient's coagulability status during effective postpartum hemorrhage management. Baseline values of rotational thromboelastometry (ROTEM) have not yet been reported in a heterogeneous obstetric population. This study aimed to establish a baseline for a diverse population representative of the United States. The secondary aim was to evaluate the association of these hematologic parameters with comorbidities, race, and socioeconomic factors.

Methods

The study was a retrospective review of collected ROTEM values of women undergoing vaginal or cesarean delivery with a history of or at risk for postpartum hemorrhage. Patients were divided into healthy and comorbid groups. Exclusion criteria for both groups included active or recent bleeding, receipt of blood products or clot-enhancing factors, and liver disease. Mean values of ROTEM by race and comorbidities were included. Median values were reported for intrinsic pathway thromboelastometry (INTEM), extrinsic pathway thromboelastometry (EXTEM), and fibrin polymerization thromboelastometry (FIBTEM) amplitude at 10 minutes (A10) and 20 minutes (A20), coagulation time, clot formation time, and maximum clot firmness.

Results

A total of 681 records were reviewed; 485 met inclusion criteria, and 267 met healthy criteria. The mean (standard deviation) demographics for maternal age (years), body mass index (kg/m2), and gestational age (weeks) were 32.2 (5.7), 34 (7.3), and 35.4 (5), respectively. The median INTEM, EXTEM, and FIBTEM A10 were 63, 65, and 23 mm. The mean for INTEM, EXTEM, and FIBTEM A10 was increased for those who were Black or obese, whereas a decreased FIBTEM and EXTEM A10 was noted in those who were Asian or those who had the hemolysis, elevated liver enzymes, low platelet syndrome.

Conclusions

Our heterogeneous population presents ROTEM values within the interquartile range of those previously reported in European studies. Black race, obesity, and preeclampsia were associated with hypercoagulable profiles.

Epidemiology and prevention of venous thromboembolism

Venous thromboembolism, that consists of the interrelated conditions deep-vein thrombosis and pulmonary embolism, is an under-appreciated vascular disease. In Western regions, approximately 1 in 12 individuals will be diagnosed with venous thromboembolism in their lifetime. Rates of venous thromboembolism are lower in Asia, but data from other regions are sparse. Numerous risk factors for venous thromboembolism have been identified, which can be classified as acute or subacute triggers (provoking factors that increase the risk of venous thromboembolism) and basal or acquired risk factors (which can be modifiable or static). Approximately 20% of individuals who have a venous thromboembolism event die within 1 year (although often from the provoking condition), and complications are common among survivors. Fortunately, opportunities exist for primordial prevention (prevention of the development of underlying risk factors), primary prevention (management of risk factors among individuals at high risk of the condition) and secondary prevention (prevention of recurrent events) of venous thromboembolism. In this Review, we describe the epidemiology of venous thromboembolism, including the incidence, risk factors, outcomes and opportunities for prevention. Meaningful health disparities exist in both the incidence and outcomes of venous thromboembolism. We also discuss these disparities as well as opportunities to reduce them.

Gout and risk of venous thromboembolism: A systematic review and meta-analysis of cohort studies

BACKGROUND

The association between gout and venous thromboembolism (VTE) remains ambiguous, and the results of current studies are inconsistent. A systematic review and meta-analysis of cohort studies were conducted to comprehensively assess the associations between gout and VTE and its subtypes, deep venous thrombosis (DVT) and pulmonary embolism (PE).

METHODS

PubMed, Web of Science, Embase, Scopus, and the Cochrane Library databases were searched up to June 2021, to identify eligible cohort studies, reporting the association of gout with VTE and its subtypes. We pooled hazard ratios (HRs) with 95% confidence intervals (CIs). Subgroup analysis, sensitivity analysis, and publication bias tests were also conducted.

RESULTS

Five studies involving 642 632 individuals were included. Patients with gout had a statistically significantly higher risk of VTE (HR: 1.33; 95% CI: 1.21, 1.46; P < .001) compared with non-gout controls, and significant associations were also found between gout and DVT (HR: 1.40; 95% CI: 1.22, 1.62; P < .001) and PE (HR: 1.18; 95% CI: 1.07, 1.30; P = .001). Subgroup analysis showed this association in men (HR: 1.37; 95% CI: 1.14, 1.65; P = .001) and women (HR: 1.36; 95% CI: 1.21, 1.53; P < .001) were consistent (P = .980). Meta-regression analysis revealed publication year (P = .005) and quality of study (P = .006) contributed to heterogeneity.

CONCLUSIONS

In conclusion, our study provided evidence that gout was associated with the risk of VTE and its subtypes DVT and PE. However, more prospective and high-quality clinical evidence is required to confirm our findings.

Race does matter: venous thromboembolism in trauma patients with isolated severe pelvic fractures

PURPOSE

Studies in non-trauma populations have shown that Black patients have a higher risk of venous thromboembolism (VTE) compared to other races. We sought to determine whether this association exists in trauma patients. The incidence of VTE is particularly high following severe pelvic fractures. To limit confounding factors associated with additional injuries, we examined patients with isolated blunt severe pelvic fractures.

METHODS

The TQIP database (2013-2017) was queried for all patients who sustained isolated blunt severe pelvic fractures (AIS ≥ 3) and received VTE prophylaxis (VTEp) with either unfractionated heparin or low molecular weight heparin. The study groups were Asian, Black, and White race as defined by TQIP. The primary outcome was differences in the rate of thromboembolic events.

RESULTS

A total of 9491 patients were included in the study. Of these, 232 (2.4%) were Asian, 1238 (13.0%) Black, and 8021 (84.5%) White. There was no significant difference in the distribution of pelvis AIS 3,4,5 between the groups. Black patients had a significantly higher incidence of VTE, DVT and PE compared to Asians and Whites. After adjusting for differences between the groups, Black patients had higher odds of developing pulmonary embolism (OR 1.887, 95% CI 1.101-3.232, p = 0.021) compared to White patients.

CONCLUSIONS

In this nationwide study of trauma patients with severe pelvic fractures, Black patients were more likely to develop pulmonary embolism compared to White patients. Further research to identify the determinants of racial disparities in trauma-related VTE is warranted, to target interventions that can improve VTE outcomes for all patients.

Anticoagulation Strategies in Non-Critically Ill Patients with Covid-19

BACKGROUND: Optimal thromboprophylaxis for hospitalized patients with coronavirus disease 2019 (Covid-19) is uncertain. METHODS: In an open-label, adaptive platform trial, we randomly assigned hospitalized adults with Covid-19 to low-dose low-molecular-weight heparin thromboprophylaxis or intermediate-dose or low-dose plus aspirin. In response to external evidence, the aspirin intervention was discontinued and a therapeutic-dose arm added. The primary end point was death or the requirement for new organ support by day 28, analyzed with a Bayesian logistic model. Enrolment was closed as a result of operational constraints. RESULTS: Between February 2021 and March 2022, 1574 patients were randomly assigned. Among 1526 participants included in the analysis (India, n=1273; Australia and New Zealand, n=138; and Nepal, n=115), the primary outcome occurred in 35 (5.9%) of 596 in low-dose, 25 (4.2%) of 601 in intermediate-dose, 20 (7.2%) of 279 in low-dose plus aspirin, and 7 (14%) of 50 in therapeutic-dose anticoagulation. Compared with low-dose thromboprophylaxis, the median adjusted odds ratio for the primary outcome for intermediate-dose was 0.74 (95% credible interval [CrI], 0.43 to 1.27; posterior probability of effectiveness [adjusted odds ratio<1; Pr], 86%), for low-dose plus aspirin 0.88 (95% CrI, 0.47 to 1.64; Pr, 65%), and for therapeutic-dose anticoagulation 2.22 (95% CrI, 0.77 to 6.20; Pr, 7%). Overall thrombotic and bleeding rates were 0.8% and 0.4%, respectively. There were 10 serious adverse reactions related to anticoagulation strategy, of which nine were grade 1 or 2 across study interventions and one grade 4 episode of retroperitoneal hematoma in a patient receiving intermediate-dose anticoagulation. CONCLUSIONS: In hospitalized non–critically ill adults with Covid-19, compared with low-dose, there was an 86% posterior probability that intermediate-dose, 65% posterior probability that low-dose plus aspirin, and a 7% posterior probability that therapeutic-dose anticoagulation reduced the odds of death or requirement for organ support. No treatment strategy met prespecified stopping criteria before trial closure, precluding definitive conclusions. (Funded by Australian National Health and Medical Research Council or Medical Research Future Fund Investigator and Practitioner Grants and others; ClinicalTrials.gov number, NCT04483960.)

The Risk of Thrombosis Around Pregnancy: Where Do We Stand?

Pregnancy and puerperium increase the relative risk of venous thromboembolism (VTE) and the absolute risk remains low, around 1 per 1,000, with induced mortality of around 1 per 100,000. Analysis of large databases has helped specify the modes of presentation and risk factors (RF) whose impact is greater after than before childbirth, since VTE during pregnancy and post-partum obey different RFs. The evolution of the population concerned (mostly women over 35, obese, of multi-ethnicity undergoing medically assisted reproduction) affects the frequency of these RFs. Pulmonary embolism (PE) is over-represented after childbirth, but 30% of PE in pregnancy occurs without any RFs. Recommendations for prevention, mainly from expert groups, are heterogeneous and often discordant. Low molecular weight heparins (LMWH) are the mainstay of pharmacological thromboprophylaxis, in a field where randomized controlled studies are definitely lacking. VTE risk assessment in pregnancy must be systematic and repetitive. Risk assessment methods and scores are beginning to emerge to guide thromboprophylaxis and should be used more systematically. In the future, analyzing observational data from huge, nationwide registries and prospective cluster clinical trials may bring to light clinically relevant outcomes likely to feed comprehensive guidelines.

Hospital Variation and Associated Organizational Factors of Pregnancy-Related Venous Thromboembolism in China

Objective

Identifying organizational factors affecting venous thromboembolism (VTE) incidence and variations between hospitals.

Methods

From a 2019 survey of VTE and live births in 113 hospitals, organizational factors: (hospital type, characteristics, live birth number), resource availability: (D-dimer, B-scan ultrasonography of lower extremity veins, computed tomographic pulmonary angiography [CTPA], and competency: [risk assessment, use of anticoagulants and patient education], data were collected and the associations, weighted by live birth number, analyzed.

Results

Of 113 hospitals in China, 770,828 live births and 526 cases of VTE (68.2 per 100,000 live births) were reported. Nine hospitals lacked B-scan ultrasonography of lower extremity veins and 22 lacked CTPA. Prevalence rates of VTE rates were higher in general hospitals (Odds ratio [OR] = 4.251, 95% CI: 3.373-5.357), hospitals with live births < 10,000 (OR = 1.650-2.193), and hospitals without B-scan ultrasonography (OR = 1.661, 95% CI: 1.096-2.518). Hospitals implementing patient education, had a lower risk of VTE (OR = 0.296-0.374), and VTE rate decreased with the annual increase in live births.

Conclusions

Improved hospital resource availability and competency, especially patient education, is vital for reducing VTE-related maternal mortality and morbidity risk.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.

RESULTS

Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Ethnic differences in thromboprophylaxis for COVID-19 patients: should they be considered?

Thromboembolic events contribute to morbidity and mortality in coronavirus disease 2019 (COVID-19). As a result, thromboprophylaxis using low-molecular-weight heparin (LMWH) is universally recommended for hospitalized patients based on multiple guidelines. However, ethnic differences with respect to thrombogenicity have been reported and the incidence of thromboembolic events is considered to be lower in the Asian population. Despite the importance of thromboprophylaxis, bleeding is also a side effect that should be considered. We examine the data relating to potential ethnic differences in thrombosis and bleeding in COVID-19. Although sufficient data is not yet available, current evidence does not oppose routine anticoagulant use and thromboprophylaxis using a standard dose of LMWH for admitted patients regardless of ethnicity based on our review.

Ethnoracial variations in venous thrombosis: Implications for management, and a call to action

Despite decades of improvement in its diagnosis and management, venous thromboembolism (VTE) remains a significant cause of cardiovascular morbidity and mortality. Clinically relevant differences exist in the risk of symptomatic VTE among ethnoracial groups. Underlying these differences in rates of VTE are patterns of known genetic thrombophilias, which may also influence the risks of major bleeding related to vitamin K antagonists or direct oral anticoagulants. In addition, social factors, differential access to care, and disease awareness differ between ethnoracial groups, which contributes to disparities in VTE outcomes that include higher fatal events. The vast majority of participants included in clinical trials for the prevention and treatment of VTE have been White Caucasian, which limits our understanding of the differential impact of these agents in non-White ethnoracial groups. Increasing the participation in clinical trials of diverse ethnoracial groups should be a priority, especially those groups who are disproportionately affected by the burden of VTE, or possible bleeding complications when exposed to anticoagulants. Advocacy by patients, researchers, and regulatory bodies is crucial to ensure adequate enrolment of diverse ethnoracial groups in order to best inform clinical decisions to optimize VTE prevention and treatment for non-White populations.

Preventing postpartum venous thromboembolism: A call to action to reduce undue maternal morbidity and mortality

Postpartum venous thromboembolism (VTE) is a leading cause of maternal mortality in developed countries and can carry significant long-term morbidity. Despite being able to identify postpartum VTE risk factors in a large proportion of the obstetrical population, there is little high-quality evidence available to guide practice on who should receive postpartum thromboprophylaxis. Based on epidemiological data, women with a prior history of VTE or known potent thrombophilia are likely to benefit from an extended duration of low-molecular-weight heparin (LMWH) prophylaxis. However, significant controversy exists around the benefit and harm of postpartum thromboprophylaxis in women with more modest risk factors, such as those with mild thrombophilias or transient situational risk factors around labor and delivery, such as cesarean delivery. We review the available data for postpartum VTE risk factors and thromboprophylaxis in these patients. This review highlights the latest evidence in the area of postpartum VTE prevention, and is a call to action for further research in this area to improve maternal morbidity and mortality.

A local risk score model for venous thromboembolism prophylaxis for caesarean section in Chinese women and comparison with international guidelines

OBJECTIVE

Recommendations for venous thromboembolism (VTE) prophylaxis from authoritative guidelines for women undergoing caesarean delivery differed significantly and may not be applicable to Chinese populations. We aim to formulate a local risk model for VTE prophylaxis for caesarean section women.

MATERIAL AND METHODS

A local risk score model based on demographic, obstetric and medical parameters was used to assess the risk of VTE in women undergoing caesarean delivery from May 2017 to April 2018 in a regional obstetric unit. Women with increased risk (VTE Score ≥ 2) are given mechanical prophylaxis with pneumatic cuff and those with high risk (VTE Score ≥ 3) are additionally prescribed low molecular weight heparin (LMWH) as pharmacological prophylaxis in the early postpartum period. The risk scores obtained by applying other major guidelines were then compared.

RESULTS

Of 859 patients were included for analysis, overweight (15.3%), advanced maternal age (9.7%), multiple pregnancy (5.1%), obesity (4.7%), and primary postpartum haemorrhage (4.1%) were the most common risk factors. Overall, 109 (12.7%) patients required mechanical prophylaxis and 28 (3.3%) patients required additional pharmacological prophylaxis. No patient had postpartum VTE events nor serious haemorrhage after receiving LMWH prophylaxis. In contrast, applying the Royal College of Obstetricians and Gynaecologists guidelines to our cohort, 649 (75.6%) patients would receive LMWH after caesarean section, compared with no patients under the American College of Obstetrics and Gynaecology guidelines.

CONCLUSIONS

Our local risk score model avoided the need for large proportions of women to be subjected to pharmacological prophylaxis, and appeared safe and practical.

American Society of Hematology 2018 guidelines for management of venous thromboembolism: venous thromboembolism in the context of pregnancy

BACKGROUND

Venous thromboembolism (VTE) complicates ∼1.2 of every 1000 deliveries. Despite these low absolute risks, pregnancy-associated VTE is a leading cause of maternal morbidity and mortality.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians and others in decisions about the prevention and management of pregnancy-associated VTE.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations.

RESULTS

The panel agreed on 31 recommendations related to the treatment of VTE and superficial vein thrombosis, diagnosis of VTE, and thrombosis prophylaxis.

CONCLUSIONS

There was a strong recommendation for low-molecular-weight heparin (LWMH) over unfractionated heparin for acute VTE. Most recommendations were conditional, including those for either twice-per-day or once-per-day LMWH dosing for the treatment of acute VTE and initial outpatient therapy over hospital admission with low-risk acute VTE, as well as against routine anti-factor Xa (FXa) monitoring to guide dosing with LMWH for VTE treatment. There was a strong recommendation (low certainty in evidence) for antepartum anticoagulant prophylaxis with a history of unprovoked or hormonally associated VTE and a conditional recommendation against antepartum anticoagulant prophylaxis with prior VTE associated with a resolved nonhormonal provoking risk factor.

Safety and efficacy of adjusted-dose enoxaparin in pregnant patients with increased risk for venous thromboembolic disease

OBJECTIVE

To assess the efficacy and safety of anti-Xa guided dose-adjusted low molecular weight heparin (LMWH) thromboprophylaxis in at-risk pregnant women.

METHODS

This single-center retrospective study was conducted at a quaternary hospital in Johannesburg, South Africa. We analyzed clinical and laboratory data for pregnant patients referred between January 1, 1999, and May 1, 2017, with an increased risk of venous thromboembolic disease (VTED) and treated with prophylactic LMWH adjusted according to anti-Xa levels. The efficacy endpoint was pregnancy-related VTED and/or pregnancy loss despite anti-Xa guided dose-adjusted LMWH thromboprophylaxis.

RESULTS

We reviewed data for 113 consecutive pregnant patients with 151 pregnancies referred for prophylactic LMWH. Prevalence of pregnancy-related VTED was 1.3% (95% confidence interval [CI] 0.1-4.7), which is lower than that reported in the literature for fixed-dose thromboprophylaxis in similar at-risk groups. One venous thromboembolism event occurred in the antenatal period (despite adequate prophylaxis) and the second in the postpartum period (related to prolonged labor). Prevalence of pregnancy-related bleeding was 2% (95% CI 0.4-5.7) with all bleeding events considered to be minor and unrelated to LMWH therapy.

CONCLUSION

This study demonstrated the efficacy and safety of anti-Xa dose-adjusted LMWH thromboprophylaxis in at-risk pregnant patients.

Correction of Facial Deformity in Sturge-Weber Syndrome

Background:

Although previous studies have reported soft-tissue management in surgical treatment of Sturge–Weber syndrome (SWS), there are few reports describing facial bone surgery in this patient group. The purpose of this study is to examine the validity of our multidisciplinary algorithm for correcting facial deformities associated with SWS. To the best of our knowledge, this is the first study on orthognathic surgery for SWS patients.

Methods:

A retrospective chart review included 2 SWS patients who completed the surgical treatment algorithm. Radiographic and clinical data were recorded, and a treatment algorithm was derived.

Results:

According to the Roach classification, the first patient was classified as type I presenting with both facial and leptomeningeal vascular anomalies without glaucoma and the second patient as type II presenting only with a hemifacial capillary malformation. Considering positive findings in seizure history and intracranial vascular anomalies in the first case, the anesthetic management was modified to omit hypotensive anesthesia because of the potential risk of intracranial pressure elevation. Primarily, both patients underwent 2-jaw orthognathic surgery and facial bone contouring including genioplasty, zygomatic reduction, buccal fat pad removal, and masseter reduction without major complications. In the second step, the volume and distribution of facial soft tissues were altered by surgical resection and reposition. Both patients were satisfied with the surgical result.

Conclusions:

Our multidisciplinary algorithm can systematically detect potential risk factors. Correction of the asymmetric face by successive bone and soft-tissue surgery enables the patients to reduce their psychosocial burden and increase their quality of life.

Pre-pregnancy BMI, delivery BMI, gestational weight gain and the risk of postpartum venous thrombosis

OBJECTIVE

To characterize the risk of postpartum venous thromboembolism (VTE) associated with body-mass-index (BMI) in both pre-pregnancy and at delivery, and with gestational weight gain (GWG).

METHODS

In a population-based, case-control study, we identified all women in Washington State with ICD-9 codes for VTE in the postpartum period between 2003 and 2011. Controls were women without VTE in the postpartum period, matched by delivery year to cases. Pre-pregnancy BMI, delivery BMI, and covariates were abstracted from birth certificates. Adjusted logistic regression models separately estimated postpartum VTE risk associated with categories of BMI in pre-pregnancy and at delivery.

RESULTS

Cases (n=289) had a higher mean BMI than controls (n=4208) pre-pregnancy (29.9kg/m(2) and 26.3kg/m(2), respectively) and at delivery (34.8kg/m(2) vs. 31.4kg/m(2), respectively), with similar gestational weight gains. Compared with women with a normal pre-pregnancy BMI (18.5-24.9kg/m(2)), overweight (BMI 25-29.9kg/m(2)) and obese (BMI≥30kg/m(2)) women were at a 1.5-fold and 1.8-4 fold greater risk of postpartum VTE, respectively, with greatest risks in women with class III obesity (BMI≥40kg/m(2): OR 4.0, 95%CI 2.7-6.3). Observed associations of delivery BMI with postpartum VTE were less strong than those of pre-pregnancy BMI. Large weight gains during pregnancy (>22kg) also contributed to greater VTE risks (OR 1.5, 95%CI 1.0-2.2).

CONCLUSION

Maternal BMI is an important risk factor for postpartum VTE, grading from weak in overweight women to very strong in women with class III obesity. Care providers may prefer to use pre-pregnancy BMI, along gestational weight gain, when stratifying the risk of postpartum VTE at delivery.

Ethnic diversity in the genetics of venous thromboembolism

Genetic susceptibility is considered as a crucial factor for the development of venous thromboembolism (VTE). Epidemiologic and genetic studies have revealed clear disparities in the incidence of VTE and the distribution of genetic factors for VTE in populations stratified by ethnicity worldwide. While gain-of-function polymorphisms in the procoagulant genes are common inherited factors in European-origin populations, the most prevalent molecular basis for venous thrombosis in Asians is confirmed to be dysfunctional variants in the anticoagulant genes. With the breakthrough of genomic technologies, a set of novel common alleles and rare mutations associated with VTE have also been identified, in different ethnic groups. Several putative pathways contributing to the pathogenesis of thrombophilia in populations of African-ancestry are largely unknown, as current knowledge of hereditary and acquired risk factors do not fully explain the highest risk of VTE in Black groups. In-depth studies across diverse ethnic populations are needed to unravel the whole genetics of VTE, which will help developing individual risk prediction models and strategies to minimise VTE in all populations.

Association between newborn birth weight and the risk of postpartum maternal venous thromboembolism: a population-based case-control study

BACKGROUND

Postpartum venous thromboembolism (VTE) is a potentially fatal and preventable event leading to substantial short- and long-term morbidity. We sought to evaluate whether the delivery of term newborns of low or high birth weight was associated with greater risks of VTE.

METHODS AND RESULTS

In a population-based case-control study conducted in Washington State from 1987 through 2011, cases of hospitalized VTE within 3 months of delivery were identified by using selected International Classification of Diseases, Ninth Revision, Clinical Modification codes. Controls were randomly selected postpartum women without VTE, matched on birth year. Birth weight and other maternal and pregnancy characteristics were extracted from birth certificate data. Among term live singleton deliveries, we compared the risk of VTE for mothers of newborns of low and high birth weights (<2500 g and >4000 g, respectively) versus mothers of newborns of normal birth weight (2500-4000 g). Logistic regression models were adjusted for maternal age, race, education, body mass index, parity, delivery methods, gestational length, smoking, gestational diabetes mellitus, and preeclampsia. Patients with VTE (n=547) were older, had a higher body mass index, and experienced more pregnancy-related complications than controls (n=9482). In comparison with mothers of newborns with normal birth weight, mothers of newborns with low birth weight had a 3-fold increased risk of VTE, which persisted after multivariable adjustment (odds ratio, 2.98; 95% confidence interval, 1.80-4.93). Mothers of newborns with high birth weight had only a slightly increased risk of VTE, which was attenuated after multivariable adjustment (odds ratio, 1.26; 95% confidence interval, 0.99-1.61).

CONCLUSIONS

The delivery of a newborn with low birth weight is associated with a 3-fold increased risk of maternal postpartum VTE. This should be considered when assessing VTE risk at delivery.

Disparities in rates of inpatient mortality and adverse events: race/ethnicity and language as independent contributors

Patients with limited English proficiency have known limitations accessing health care, but differences in hospital outcomes once access is obtained are unknown. We investigate inpatient mortality rates and obstetric trauma for self-reported speakers of English, Spanish, and languages of Asia and the Pacific Islands (API) and compare quality of care by language with patterns by race/ethnicity. Data were from the United States Agency for Healthcare Research and Quality, Healthcare Cost and Utilization Project, 2009 State Inpatient Databases for California. There were 3,757,218 records. Speaking a non-English principal language and having a non-White race/ethnicity did not place patients at higher risk for inpatient mortality; the exception was significantly higher stroke mortality for Japanese-speaking patients. Patients who spoke API languages or had API race/ethnicity had higher risk for obstetric trauma than English-speaking White patients. Spanish-speaking Hispanic patients had more obstetric trauma than English-speaking Hispanic patients. The influence of language on obstetric trauma and the potential effects of interpretation services on inpatient care are discussed. The broader context of policy implications for collection and reporting of language data is also presented. Results from other countries with and without English as a primary language are needed for the broadest interpretation and generalization of outcomes.