Venous thromboembolism in pregnant women with sickle cell disease: a retrospective database analysis

Maternal and Infant Outcomes in a Subset of Patients with Sickle Cell Disease in South Carolina

OBJECTIVES

Sickle cell disease (SCD), which disproportionately affects minorities, increases complications during pregnancy. Severe maternal mortality is increased in women with SCD, including morbidity related to the disease and other nondisease-related complications. It also can have devastating complications for fetuses, with increases in premature birth and low birth weight. This study aimed to describe the characteristics of women with SCD in South Carolina, with a specific focus on fetal and maternal outcomes and complications. The secondary aim of this study was to identify the effect of maternal characteristics on birth outcomes, including social determinants of health.

METHODS

A secondary analysis of women from a single institution, the Medical University of South Carolina, which was part of the registry from the multi-institutional Sickle Cell Disease Implementation Consortium, was conducted. Patient demographics, self-reported pregnancy history, hydroxyurea use, and maternal and fetal outcomes were collected from patient-reported survey data. In addition, the number of vaso-occlusive episodes surrounding their pregnancies was collected for analysis.

RESULTS

Fifty-nine percent (116/195) of the female participants reported ever being pregnant. Seventy-two percent had live births, 15.8% had miscarriages, 1.8% had stillbirths, and 6.1% had an abortion. The mean age was 22.3 ± 4 years, with no difference in markers of severity between the groups. Most women were HbSS genotype with high rates of pain in the last year. No difference was found in age, education, employment, or income between these groups of women. Women in the nonlive birth cohort had higher body weights (78.7 versus 72.1 kg, P = 0.045). The Distressed Community Index was used as a marker for social determinants of health and was similar between the two groups, with a majority of both cohorts (61.7% and 52%) living in "at risk" and "distressed" communities. Complications related to SCD were high, including 43% of women experiencing pain during pregnancy, 5.2% developing acute chest syndrome, and 22.4% requiring transfusion. An additional 11% experienced preeclampsia. Unfavorable infant outcomes included 49% of the infants being premature and 40% having babies weighing less than 5.5 lb at birth.

CONCLUSIONS

High rates of complications to both mother and infant were found in the women with SCD. Although few statistically significant predictors were found, by identifying and addressing specific needs of pregnant women with SCD, we can work toward reducing fetal and maternal mortality in an already vulnerable population.

Venous Thromboembolism in Individuals with Sickle Cell Disease: A Narrative Review

Sickle cell disease (SCD) is an inherited hemoglobinopathy characterized by vaso-occlusion, hemolysis of red blood cells (RBC), and a predisposition for venous thromboembolism (VTE). The sickling and hemolysis of RBC culminate in coagulation system abnormalities, platelet activation, endothelial dysfunction, and impaired blood flow manifesting as a prothrombotic state. In addition, individuals with SCD are often exposed to extrinsic risk factors for VTE including recurrent hospitalizations, central venous catheters, and acute medical illnesses. The diagnosis is often challenging as symptoms may mimic other complications of SCD, and there is little data to guide diagnostic algorithms involving probability scoring in the SCD population. Non-anticoagulant strategies aimed at reducing disease severity may aid in lowering the risk of VTE, but data is limited. Furthermore, high quality evidence regarding anticoagulation in prevention and treatment of SCD is severely lacking, resulting in heterogeneity in clinical practice. In this narrative review we aim to review the prothrombotic pathophysiology of SCD, to describe the risk factors, high risk of mortality, and types of VTE in SCD, to develop an approach to the diagnosis of VTE in SCD, and to understand the limited available evidence for the prevention and treatment of VTE in SCD.

Plasminogen activator inhibitor-2 and impaired fibrinolysis in pregnancy and sickle cell anemia

PURPOSE

This is the first study that aimed to determine antigen levels in plasma and genotypes of PAI-2 in pregnant and non-pregnant homozygous sickle cell anemia (SCA) patients.

METHODS

The study subjects were all Bahraini females in the reproductive age group. The study population included 31 pregnant homozygous SS (SCA) patients. Three control groups were also studied to evaluate the effect of pregnancy and SCA on PAI-2 levels and fibrinolysis: (1) 31 healthy non-pregnant volunteers; (2) 31 cases of normal pregnancy; and (3) 20 non-pregnant SCA patients. Pregnancies were screened in the second (TM2) and third (TM3) trimesters. Global coagulation, fibrinolysis rate (euglobulin clot lysis time, ECLT), PAI-2 antigen (ELISA), and PAI-2 Ser(413)/Cys polymorphism (restriction fragment length polymorphism analysis) were determined.

RESULTS

Feto-maternal complications were documented in both pregnancy groups. PAI-2 antigen levels were undetectable in the non-pregnant groups, but was quantifiable in both pregnant groups. Impaired fibrinolysis rate and rising PAI-2 levels with progression of pregnancy were observed in both healthy and SCA subjects. These changes were more prominent in SCA, although the rise in ECLT was less steep and PAI-2 antigen levels were not significantly different compared to normal pregnancy in the third trimester. No correlation was observed between PAI-2 genotypes and plasma antigen levels. Also, no significant difference in feto-maternal complications was found in normal (n = 25) versus SCA pregnant patients (n = 30).

CONCLUSIONS

These observations suggest that with progression of pregnancy, increasing PAI-2 levels contribute to the hypercoagulable state, particularly in SCA patients.

Evaluating thromboprophylaxis in the sickle cell disease population: Navigating the evidence gap

Sickle cell disease (SCD) arises from beta-globin gene mutations, with global estimates indicating around 500 000 affected neonates in 2021. In the United States, it is considered rare, impacting fewer than 200 000 individuals. The key pathogenic flaw lies in mutant haemoglobin S, prone to polymerization under low oxygen conditions, causing erythrocytes to adopt a sickled shape. This leads to complications like vascular occlusion, haemolytic anaemia, inflammation and organ damage. Beyond erythrocyte abnormalities however, there is a body of literature highlighting the hypercoagulable state that is likely a contributor to many of the complications we see in SCD. The persistent activation of the coagulation cascade results in thromboembolic events, notably venous thromboembolism (VTE) which is independently associated with increased mortality in both adults and children with SCD. While the increased risk of VTE in the SCD population seems well established, there is a lack of guidelines for thromboprophylaxis in this population. This Wider Perspective will describe the hypercoagulable state and increased thrombosis risk in the SCD population, as well as advocate for the development of evidence-based guidelines to aid in the prevention of VTE in SCD.

Venous thromboembolism in pregnancy and postpartum: an illustrated review

The topic of this review is venous thromboembolism (VTE) during pregnancy and postpartum. The following topics will be addressed: epidemiology and pathophysiology of VTE in pregnancy and postpartum, diagnostic considerations for VTE in pregnancy, indications for prophylactic and therapeutic anticoagulation in pregnancy and postpartum, choice of anticoagulation in pregnancy and breastfeeding, anticoagulation management during labor and delivery, and anticoagulation considerations for assisted reproductive technology.

Sickle-Cell Trait as a Risk Factor for an Unprovoked Venous Thromboembolism: A Case Report

In this case report, we examine the increased risk of venous thromboembolism (VTE) in patients with sickle-cell trait (SCT), illustrated by a patient with SCT who developed pulmonary embolism (PE) despite low scores on conventional risk assessment tools. The case prompts both a discussion of risk assessment and management strategies in this population.

Pregnancy-related thromboembolism in women with sickle cell disease: An analysis of National Medicaid Data

Pregnancy and sickle cell disease (SCD) both individually carry a risk of thromboembolism (TE). Pregnancy in people with SCD may further enhance the prothrombotic effect of the underlying disease. The objectives of this study were to determine the rate and risk factors for arterial and venous thrombosis in pregnant people with SCD. Administrative claims data from the United States Centers for Medicare and Medicaid Service Analytic eXtract from 2006 to 2018 were used. The study population included people with SCD from the start of their first identified pregnancy until 1 year postpartum and a control cohort of pregnant people without SCD of similar age and race. Outcomes of interest were identified with ICD-9 or 10 codes. Logistic regression analyses were used to analyze risk factors. We identified infant deliveries in 6388 unique people with SCD and 17 110 controls. A total of 720 venous thromboembolism (11.3%) and 335 arterial TE (5.2%) were observed in people with SCD compared to 202 (1.2%) and 95 (0.6%) in controls. People with SCD had an 8-11 times higher odds of TE compared to controls (p < .001). Within the SCD cohort, age, hemoglobin SS (HbSS) genotype, hypertension, and history of thrombosis were identified as independent risk factors for pregnancy-related TE. Pregnancy-specific factors (pre-eclampsia, eclampsia, multigestational pregnancy) were not associated with TE. In conclusion, the risk of pregnancy-related TE is considerably higher in people with SCD compared with controls without SCD. Hence, people with SCD, particularly those with multiple risk factors may be candidates for thromboprophylaxis during pregnancy and the postpartum period.

Hypercoagulability in Sickle Cell Disease: A Thrombo-Inflammatory Mechanism

Sickle cell disease (SCD) is a group of inherited disorders characterized by the presence of abnormal hemoglobin S. Patients with SCD suffer from frequent episodes of anemia, chronic hemolysis, pain crisis, and vaso-occlusion. Additionally, SCD is associated with diverse and serious clinical complications, including thrombosis, which can lead to organ failure, increased morbidity, and eventually, mortality. SCD is known to be a hypercoagulable condition, and the cause of hypercoagulability is multifactorial, with the molecular basis of hemoglobin S being the main driver. The presence of hemoglobin S induces sickling of the RBCs and their subsequent hemolysis, as well as oxidative stress. Both of these processes can alter the hemostatic system, through the activation of platelets, coagulation system, and fibrinolysis, as well as depletion of coagulation inhibitors. These changes can also induce the formation of microvesicles and expression of tissue factor, leading to activation of WBCs, endothelial cell damage, and inflammatory response. Understanding the various factors that drive hypercoagulability as a thrombo-inflammatory mechanism in SCD can help provide explanations for the pathogenesis and other complications of the disease.

Predisposing Factors and Incidence of Venous Thromboembolism among Hospitalized Patients with Sickle Cell Disease

Though patients with sickle cell disease (SCD) are at risk of developing venous thromboembolism (VTE), clear estimates of its incidence and predisposing factors in hospitalized SCD patients are not available. Therefore, this issue was addressed to facilitate an early diagnosis and initiate appropriate prophylactic and treatment strategies. A retrospective observational study was conducted on patients with SCD who were admitted to an academic center in Saudi Arabia over a 10-year period. We identified 1054 admissions of 394 patients with SCD. Of the 3% of patients identified with VTE, 50% experienced pulmonary embolism (PE), 34.3% exhibited deep vein thrombosis (DVT), 6.3% exhibited cerebral vein thrombosis, and 9.4% showed other forms of VTE. In pregnant SCD patients, 6.4% developed a VTE event during their hospital admission. Of the risk factors, high white blood cell count, length of stay, and presence of any additional risk factor for VTE was associated significantly with higher risk of VTE. In our study, this risk seems to be much lower, which is likely attributed to the use of VTE prophylactic strategies implemented in our center. Nevertheless, further studies are needed to establish the ideal prophylactic strategy in patients with SCD.

A Comprehensive Review of Pregnancy in Sickle Cell Disease

Sickle cell hemoglobinopathies encompass a range of qualitative and quantitative hemoglobin disorders that are inherited genetically. This group of disorders includes sickle cell beta thalassemia, sickle cell trait, and sickle cell disease (SCD). Globally, SCD is the most common disorder. Even epidemiological data suggests the majority of diseases, as well as traits, are concentrated in Sub-Saharan Africa, North-East Africa, the Middle East, and India. The physiological changes in pregnancy predispose to an increased risk of catastrophic events like a vaso-occlusive crisis, thromboembolic events, and their related sequelae, leading eventually to villous infarction, necrosis, and fibrosis leading to compromising uteroplacental circulation. Conversely, the mother may exhibit exacerbated symptoms of gestational hypertension, placental abruption, preterm labor, and venous thromboembolism. Although this disease is manageable, it has the potential to adversely impact maternal and child health on a national level. The chances of severe complications in the pregnant state affecting both mother and fetus attract due attention of health services towards redefining and researching this disease and its management frequently. The literature review on the following situation advocates the general treatment to be observed under the headings of preconceptual care, strengthened antenatal care, strict intranatal care, and compliant post-natal care. Preconceptually, genetic screening of couples, with education on the adverse effects of the disease, comes as the first line of management. Newer facilities like preimplantation genetic diagnosis and celocentesis may even allow for early diagnosis as well as help patients who do not wish to terminate the pregnancy by selective transfer of unaffected embryos. This may be combined with an extensive evaluation of the psychosocial aspect and socioeconomic status of couples who administer vaccines as prophylaxis for preventable diseases. Strengthening antenatal care is associated with routine blood investigations for every registered antenatal patient with adequate awareness about the conditions that precipitate the crisis. All patients should be prophylactically treated with appropriate doses of aspirin, iron, folic acid, and multivitamins. Radiological examinations by ultrasonography may be used to monitor placenta previa, abruption, or preterm labor. Later in pregnancy, it should be recommended to perform biophysical profiling and assessment of umbilical artery flow. Intranatal care deals with strict-term institutional delivery of all sickle cell-diseased mothers with a preference for vaginal delivery. Post-natal care requires a precise assessment of blood loss during labor to initiate transfusion therapy as soon as needed. Exclusive breastfeeding, with the importance of early initiation of it, must be emphasized. Screening of neonates as quickly as possible must be done for hemoglobinopathies. Through this review, authors are trying to make aware of the complications that can be faced during pregnancy in SCD patients, its prevention, and its treatment according to various new guidelines and research available.

Positive rate and quality assessment of CT pulmonary angiography in sickle cell disease: a case‒control study

BACKGROUND

Pulmonary complications are common in sickle cell disease (SCD) and can mimic pulmonary embolisms (PEs), leading to potential overuse of computed tomography pulmonary angiography (CTPA). Maximizing the quality of CTPA is essential for its diagnostic accuracy. However, little is known about the positive rate and quality of CTPA in SCD.

METHODS

This retrospective case‒control study aimed to determine the positive rate and quality of CTPA studies performed to rule out PE in SCD (HbSS genotype) patients compared to a control group. Logistic regression analysis was used to identify independent factors associated with suboptimal CTPA studies, defined as a mean enhancement of < 210 HU in the pulmonary artery.

RESULTS

The study included 480 patients, consisting of 240 SCD patients and 240 controls. The positive rate of PE was 4.0%, with a similar rate in both SCD patients and the control group (4.2% vs. 3.8%, p = 0.08). However, SCD patients had significantly lower contrast enhancement of the pulmonary artery than the control group (266.1 ± 90.5 HU vs. 342.2 ± 116.1 HU, p < 0.01). Notably, 25.4% of SCD patients had suboptimal scans. The logistic regression model demonstrated that SCD was significantly associated with suboptimal pulmonary arterial contrast enhancement compared to the control group (OR = 4.4; 95% CI: 2.4-8.3).

CONCLUSIONS

This study revealed a relatively low positive rate of CTPA in both SCD patients and the control group. However, SCD was significantly associated with suboptimal image quality due to inadequate contrast enhancement of the pulmonary artery. Further research is needed to identify measures that can enhance the quality of CTPA studies in SCD patients and to establish a specific imaging protocol for this patient population.

Severe Maternal Morbidity and Mortality in Sickle Cell Disease in the National Inpatient Sample, 2012-2018

IMPORTANCE

Pregnancy outcomes are historically poor among people with sickle cell disease (SCD) in the US, most of whom have Black race. Whether outcomes have improved is unknown.

OBJECTIVE

To tabulate adverse pregnancy outcomes among patients with SCD, comparing outcomes of deliveries among Black people with SCD with those of Black people without SCD and a control non-Black population, and to measure the association of racial disparities with adverse outcomes in SCD pregnancies.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study was a secondary analysis involving data from National Inpatient Sample, a nationally representative sample of 20% of acute hospital admissions in the US, between 2012 and 2018. The data set included all admissions with codes for delivery of a pregnancy among people aged 11 to 55 years. Data were analyzed from September 2021 to August 2022.

EXPOSURES

SCD, racial disparities.

MAIN OUTCOMES AND MEASURES

Severe maternal morbidity (SMM) as measured by the US Centers for Disease Control and Prevention's index alongside other outcomes; multiple logistic regression was used to compare the odds for adverse pregnancy outcomes.

RESULTS

The sample included 5 401 899 deliveries, including 3901 deliveries among people with SCD and 742 164 deliveries among people with Black race. Compared with the non-Black control group, patients with SCD and Black patients were younger (mean [SD] age: SCD, 27.2 [5.9] years; Black, 27.1 [6.1] years vs 28.7 [5.9] years) and more likely to have public insurance (SCD, 2609 deliveries [67.3%]; Black, 496 828 deliveries [65.4%] vs 1 880 198 deliveries [40.8%]). The maternal mortality rate in deliveries among people with SCD was 26 times greater than in the non-Black control group and more than 10 times greater than among Black pregnant people without SCD (Per 10 000 deliveries: SCD 13.3; 95% CI, 5.7-31.2; Black race, 1.2; 95% CI, 1.0-1.5; non-Black control 0.5; 95% CI, 0.5-0.6). Compared with the control group, SCD deliveries had higher odds of SMM (adjusted odds ratio [aOR], 7.22; 95% CI, 6.25-8.34; P < .001), especially cerebrovascular events (aOR, 22.00; 95% CI, 15.25-31.72; P < .001) and thromboembolism (aOR, 17.34; 95% CI, 11.55-26.03; P < .001). Racial disparities explained a median (IQR) 28.9% (21.2%-33.1%) of the increased risk in deliveries to people with SCD and between 40% and 50% of the increased risk for acute kidney failure (excess risk [ER], 56.9%; 95% CI, 54.3%-59.3%), intrauterine fetal demise (ER, 47.8%; 95% CI, 46.6%-49.1%), and eclampsia (ER, 42.1%; 95% CI, 37.9%-46.1%).

CONCLUSIONS AND RELEVANCE

In this large cross-sectional study of pregnancy outcomes in people with SCD, the risk for SMM was higher compared with deliveries among people without SCD, especially for thrombotic events, organ failure, and death. Racial disparities were associated with adverse outcomes. Our findings compel scientific, clinical, and political effort to improve outcomes for pregnant people with SCD.

Go the Distance

This overview of reproductive and sexual health care concerns for people with sickle cell disease (SCD) addresses clinical concerns that can be complex and are inherently multidisciplinary. Clinicians must be prepared to initiate reproductive health care discussions, as these intimate concerns may not be volunteered by patients. SCD is associated with delayed onset of puberty, sickle pain during menstruation, disease-specific contraceptive considerations, high-risk pregnancy, priapism, erectile dysfunction, and offspring who inherit a hemoglobinopathy trait from affected parents. Reproductive health considerations are underrecognized, undertreated, and understudied. They need attention in primary care and specialty SCD, urology, and obstetrics and gynecology clinics.

Sex as an Independent Risk Factor for Venous Thromboembolism in Sickle Cell Disease: A Cross-Sectional Study

Venous thromboembolism (VTE) affects up to 25% of individuals with sickle cell disease (SCD), but risk factors are not well characterized. We sought to measure the prevalence of VTE among SCD patients in our health system and to describe the relationship between medical history, biological sex, and VTE. We performed a retrospective chart review of SCD patients who visited an outpatient hematology clinic within Penn Medicine between June 2014 and June 2019. Demographics and medical history were compared across those with and without a history of VTE. We developed a logistic regression model to describe factors independently associated with VTE. Of 597 patients with SCD who were identified, 147 (24.6%) had a history of VTE; 100 were female and 47 were male. In the regression model, female sex was independently associated with history of VTE (odds ratio 1.91, 95% confidence interval 1.26-2.91), as were pulmonary hypertension, hydroxyurea use, and history of stroke. Among females only, 49.7% were parous and 18.8% had used oral contraceptives, and these proportions did not differ by history of VTE. One-quarter of the SCD patients in our health system had a history of VTE, confirming significantly higher rates than in the general population. Females had twice the odds of VTE compared to males, highlighting an important sex disparity in SCD disease outcomes and raising questions regarding optimal pregnancy and contraceptive care for females with SCD.

Prevalence of venous thromboembolism and its associations in a large racially homogenous population of sickle cell disease patients

To determine the prevalence of venous thromboembolism (VTE) among adult sickle cell disease (SCD) patients in Nigeria.

METHODS

This was a multicentre retrospective study in which the medical records of adult SCD patients were reviewed. Information on demographics, steady-state haemogram, clinical phenotypes, duration of follow-up, history of VTE including risk factors and management was collected.

RESULTS

Of the 509 SCD patients with a median (IQR) duration of follow-up of 2 years, 10 (2.0%) had VTE (9 DVT and 1 PE). Their median (IQR) age was 27 (22.8-30.3) years. Identifiable risk factors for VTE included positive family history (2, 20%) surgery, splenectomy, paraplegia and cancer (1, 10% each). No risk factor was identifiable in four persons. VTE had no significant association with age and gender. VTE was significantly associated with the following events: acute chest syndrome [p = .002, odds ratio (OR) 8, 95% CI 2.2-28.9], osteonecrosis [p = .012, OR 5.24, 95% CI, 1.45-18.91] and vaso-occlusive crisis [p = .035]. Also significantly associated with VTE were pulmonary hypertension [p = .001, OR 23.3, 95%CI 5.18-105.06] and stroke [p = .032, OR 9.35, 95%CI 0.87-53.25].

CONCLUSION

The prevalence of VTE among SCD patients in Nigeria is low. It is significantly associated with vaso-occlusive crisis, pulmonary hypertension and stroke.

Predicting risk factors for thromboembolic complications in patients with sickle cell anaemia - lessons learned for prophylaxis

Objective

To assess the clinical and laboratory predictors of venous thromboembolism (VTE) in patients with sickle cell anaemia (SCA) and its relationship to morbidity and mortality.

Methods

This retrospective case–control study analysed data from patients with SCA that experienced VTE compared with matched control patients with SCA but no VTE (2:1 ratio).

Results

A total of 102 patients with SCA were enrolled (68 cases with VTE and 34 controls). Amongst the 68 cases (median age, 29.5 years), 26 (38.2%) presented with isolated pulmonary embolism (PE). A higher prevalence of splenectomy (73.5% versus 35.3%) was observed in the cases compared with the controls. A significantly higher prevalence of central venous catheter (CVC) insertion (42.6% versus 8.8%) was observed in the cases compared with the controls. High white blood cell counts, serum lactic dehydrogenase (LDH), bilirubin and C-reactive protein (CRP) and low haemoglobin (Hb) and HbF were significant risk factors for VTE. Forty-two cases (61.8%) developed acute chest syndrome, 10 (14.7%) had a stroke and seven (10.3%) died.

Conclusions

VTE in patients with SCA has a high impact on morbidity and mortality. PE was the leading presentation of VTE, with CVC insertion, high LDH, bilirubin, CRP and white blood cell counts along with low Hb and HbF constituting other significant risk factors.

The molecular basis for the prothrombotic state in sickle cell disease

The genetic and molecular basis of sickle cell disease (SCD) has long since been characterized but the pathophysiological basis is not entirely defined. How a red cell hemolytic disorder initiates inflammation, endothelial dysfunction, coagulation activation and eventually leads to vascular thrombosis, is yet to be elucidated. Recent evidence has demonstrated a high frequency of unprovoked/recurrent venous thromboembolism (VTE) in SCD, with an increased risk of mortality among patients with a history of VTE. Here, we thoroughly review the molecular basis for the prothrombotic state in SCD, specifically highlighting emerging evidence for activation of overlapping inflammation and coagulation pathways, that predispose to venous thromboembolism. We share perspectives in managing venous thrombosis in SCD, highlighting innovative therapies with the potential to influence the clinical course of disease and reduce thrombotic risk, while maintaining an acceptable safety profile.

Pulmonary complications for women with sickle cell disease in pregnancy: systematic review and meta-analysis

BACKGROUND

Sickle cell disease (SCD) is a multisystem disease characterised by vaso-occlusive crisis, chronic anaemia and a shorter lifespan. More patients with SCD are living till reproductive age and contemplating pregnancy. Pulmonary complications in pregnancy are significant causes of maternal morbidity and mortality but yet this has not been systematically quantified. A systematic review and meta-analysis were conducted to quantify the association between SCD and pulmonary complications in pregnancy.

METHODS

MEDLINE, EMBASE, Web of Science, Cochrane and Maternity and Infant Care databases were searched for publications between January 1998 and April 2019. Observational studies involving at least 30 participants were included. Random-effects models were used for statistical meta-analysis.

FINDINGS

Twenty-two studies were included in the systematic review and 18 in the quantitative analysis. The meta-analysis included 3964 pregnancies with SCD and 336 559 controls. Compared with women without SCD, pregnancies complicated by SCD were at increased risk of pulmonary thromboembolism (relative risk (RR) 7.74; 95% CI 4.65 to 12.89). The estimated prevalence of acute chest syndrome and pneumonia was 6.46% (95% CI 4.66% to 8.25%), with no significant difference between the HbSS and HbSC genotypes (RR 1.42; 95% CI 0.90 to 2.23).

INTERPRETATION

This meta-analysis highlighted a strong association between SCD and maternal pulmonary complications. Understanding the risks of and the factors associated with pulmonary complications would aid preconceptual counselling and optimal management of the condition in pregnancy, thereby reducing associated maternal morbidity and mortality.

PROSPERO REGISTRATION NUMBER

CRD42019124708.

American Society of Hematology 2019 guidelines for sickle cell disease: cardiopulmonary and kidney disease

BACKGROUND

Prevention and management of end-organ disease represent major challenges facing providers of children and adults with sickle cell disease (SCD). Uncertainty and variability in the screening, diagnosis, and management of cardiopulmonary and renal complications in SCD lead to varying outcomes for affected individuals.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in their decisions about screening, diagnosis, and management of cardiopulmonary and renal complications of SCD.

METHODS

ASH formed a multidisciplinary guideline panel that included 2 patient representatives and was balanced to minimize potential bias from conflicts of interest. The Mayo Evidence-Based Practice Research Program supported the guideline development process, including performing systematic evidence reviews up to September 2017. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE evidence-to-decision frameworks, to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 10 recommendations for screening, diagnosis, and management of cardiopulmonary and renal complications of SCD. Recommendations related to anticoagulation duration for adults with SCD and venous thromboembolism were also developed.

CONCLUSIONS

Most recommendations were conditional due to a paucity of direct, high-quality evidence for outcomes of interest. Future research was identified, including the need for prospective studies to better understand the natural history of cardiopulmonary and renal disease, their relationship to patient-important outcomes, and optimal management.

Inpatient mortality and postpartum readmission rates in sickle cell disease pregnancies: a multistate analysis, 2007-2014

OBJECTIVE

We compared post-partum outcomes between sickle cell disease (SCD) and non-sickle cell populations.

METHODS

We conducted a retrospective analysis of discharge data for 6,911,916 inpatient deliveries in the states of California, Florida, New York, Maryland, and Kentucky from 2007 to 2014 using data from the State Inpatient Databases, Healthcare Cost and Utilization Project. We compared unadjusted rates and adjusted odds of 30- and 90-d readmission rates, in-hospital mortality, length of stay (LOS), and total hospital charges in SCD, sickle cell trait, and non-sickle cell patients.

RESULTS

Compared to non-sickle cell patients, SCD patients were more than two times as likely to die in-hospital (aOR: 2.16, 95% CI: 1.15-4.04, p < .05), 27% as likely to be readmitted up to 30 d postdelivery (aOR: 1.27, 95% CI: 1.13-1.43, p < .001), and 92% as likely to be readmitted up to 90 d postdelivery (aOR 1.92, 95% CI: 1.75-2.11, p < .001). The SCD group also had a longer median LOS, greater total hospital charges, were more likely to experience a postpartum complication, and receive a blood transfusion than the non-SCD group.

CONCLUSIONS

SCD in pregnancy is associated with increased inpatient mortality, readmissions, postpartum complications, LOS, and hospital charges.

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.

Overcoming challenges of venous thromboembolism in sickle cell disease treatment

INTRODUCTION

Venous thromboembolism (VTE) is a common comorbid condition found in sickle cell disease (SCD) and is associated with increased mortality for adults with SCD. The pathophysiology that leads to the thrombophilic state in SCD has been previously reviewed; however, evidence-based guidelines to aid in diagnosis, prevention, and management of VTE are lacking. Areas covered: This review article will cover the pathophysiology underlying the hypercoagulable state, the epidemiology of VTE, and management strategies of VTE in SCD. Expert opinion: Providers should have a high suspicion for diagnosing VTE to help reduce morbidity and mortality in the SCD population. Unlike other thrombophilias, the risk of life-threatening anemia while being treated with anticoagulation is compounded with the potential complications surrounding red blood cell transfusions in this population (i.e. alloimmunization, hyperhemolysis) and this provides another complexity to managing VTE in this population. Clinical trials evaluating the risk and benefit of treatment and treatment duration are needed.

Superimposed Hepatitis C Virus in Sickle Cell Disease Pregnant Woman

Sickle cell disease (SCD) is a hereditary blood disorder that can increase complications during pregnancy and in turn negatively influence pregnancy outcomes. In addition to patients with SCD are at a high risk of been infected with hepatitis C infection. Furthermore in this study, we reported the clinical status of a pregnant woman with SCD who had hepatitis C virus infection.

Sickle cell disease and venous thromboembolism: A retrospective comparison of the rate of positive CT pulmonary angiography in the emergency department

BACKGROUND

Previous authors have reported an increased incidence of acute pulmonary embolism (PE) in patients with sickle cell disease (SCD) based on retrospective analysis of ICD codes. It is unknown whether patients with SCD have higher rates of positive CT pulmonary angiogram (CTPA) in the emergency department (ED).

METHODS

The institutional review board (IRB) approved this retrospective study; informed consent was waived. Between January 1, 2005 and May 31, 2015, 28 patients with SCD underwent a total of 78 CTPA studies in the ED. A control group of 75 non-SCD patients matched for age, gender and race underwent 78 consecutive CTPA studies in the emergency department. Modified Wells' (mWells') scores were calculated for each CTPA study performed. The studies for both groups were blind read by two fellowship trained body radiologists. Descriptive statistics were performed, with significance considered if p < 0.05.

RESULTS

The rate of positive CT pulmonary angiogram in patients with SCD was 6.4% (5/78), compared with 12.8% (10/78) in non-SCD matched controls. There was no significant difference in the rate of positive CTPA (p = 0.277). There was also no difference in the mean mWells' score between the two groups (2.44 for SCD vs. 1.95 for controls, p = 0.120).

CONCLUSION

SCD patients did not have a significantly different rate of acute PE when compared with matched controls undergoing CTPA in the ED.

Sickle cell disease, sickle trait and the risk for venous thromboembolism: a systematic review and meta-analysis

Background

Globally, sickle cell disease (SCD) is one of the most common haemoglobinopathy. Considered a public health problem, it leads to vessel occlusion, blood stasis and chronic activation of the coagulation system responsible for vaso-occlussive crises and venous thromboembolism (VTE) which may be fatal. Although contemporary observational studies suggest a relationship between SCD or sickle trait (SCT) and VTE, there is lack of a summary or meta-analysis data on this possible correlation. Hence, we propose to summarize the available evidence on the association between SCD, SCT and VTE including deep vein thrombosis (DVT) and pulmonary embolism (PE).

Methods

We searched PubMed and Scopus to identify all cross-sectional, cohort and case-control studies reporting on the association between SCD or SCT and VTE, DVT or PE in adults or children from inception to April 25, 2017. For measuring association between SCD or SCT and VTE, DVT, or PE, a meta-analysis using the random-effects method was performed to pool weighted odds ratios (OR) of risk estimates.

Results

From 313 records initially identified from bibliographic databases, 10 studies were eligible and therefore included the meta-analysis. SCD patients had significantly higher risk for VTE (pooled OR 4.4, 95%CI 2.6–7.5, p < 0.001), DVT (OR 1.1, 95% CI 1.1–1.2, p < 0.001) and PE (pooled OR 3.7, 95% CI 3.6–3.8, p < 0.001) as compared to non SCD-adults. A higher risk of VTE (OR 33.2, 95% CI 9.7–113.4, p < 0.001) and DVT (OR 30.7, 95% CI 1.6–578.2, p = 0.02) was found in pregnant or postpartum women with SCD as compared to their counterparts without SCD. Compared to adults with SCT, the risk of VTE was higher in adults with SCD (pooled OR 3.1, 95% CI 1.8–5.3, p < 0.001), and specifically in SCD pregnant or postpartum women (OR 20.3, 95% CI 4.1–102, p = 0.0003). The risk of PE was also higher in adults with SCD (OR 3.1, 95% CCI 1.7–5.9, p = 0.0004) as compared to those with SCT. The risk of VTE was higher in individuals with SCT compared to controls (pooled OR 1.7, 95% CI 1.3–2.2, p < 0.0001), but not in pregnant or postpartum women (OR 0.9, 95% CI 0.3–2.9, p = 0.863). Compared to controls, SCT was associated with a higher risk of PE (pooled OR 2.1, 95% CI 1.2–3.8, p = 0.012) but not of DVT (pooled OR 1.2, 95% CI 0.9–1.7, p = 0.157).

Conclusion

Individuals with SCD, especially pregnant or postpartum women, might have a higher risk of VTE compared to the general population. SCT might also increases the risk of VTE. However, currently available data are not sufficient to allow a definite conclusion. Further larger studies are needed to provide a definitive conclusion on the association between SCD, SCT and VTE.

Electronic supplementary material

The online version of this article (10.1186/s12959-018-0179-z) contains supplementary material, which is available to authorized users.

Description of criteria for near miss in high-complexity obstetric population with sickle cell anemia: an observational study

Introduction: Sickle cell disease (SCD) is one of the most common monogenic diseases worldwide, affecting approximately 30 million people across the globe. It is one of the most common hemoglobinopathies affecting pregnancy, particularly in the black population. Pregnant women with SCD, in conjunction with the physiological changes of pregnancy, have an increased risk of developing severe maternal and fetal complications.Materials and methods: A descriptive, observational study was conducted retrospectively to determine the maternal and neonatal disease burden of pregnant women with SCD between 2011 and 2016. The study included pregnant patients with SCD admitted to the hospital, with confirmed diagnosis through hemoglobin electrophoresis. Patients having no confirmatory testing of the disease were excluded.Results: In all, 54% (34 patients) had no previous diagnosis of sickle cell anemia or presence of sickle cell trait, and so an in-hospital diagnosis was carried out through hemoglobin gel electrophoresis, whereas the remaining 46% (28 patients) had already a peripheral diagnosis. In total, the following profiles were obtained: Hb AS 62.9% (39 patients), Hb SC 17.7% (11 patients), Hb SS 16.1% (10 patients), Hb AC 3.2% (2 patients), and Hb CC 0% (0 patients). Vaso-occlusive pain crises constituted the most common cause of hospital admission antepartum (54.8% of the general population), occurring in 100% of the patients with Hb SS and Hb AC, in 45% of the Hb SC group and in 43% of those with the Hb AS trait. The second cause of hospital admission encompassed infectious processes, which affected 45% of the general population, 30% of the Hb AS group, 60% of the Hb SS group, 77% of the Hb SC group, and 100% of the Hb AC group. The method of termination of pregnancy of 44% (27 patients) was C-section. The most common perinatal complication was preterm birth, occurring in 26% (16 patients), with the highest incidence in the Hb AC group. The second most common complication was the intrauterine growth restriction, reported in 6% (4 patients) of all patients, being most frequently in the Hb SS group.Conclusion: Pregnant women having SCD should be assessed and managed by a multidisciplinary team composed of hematology, perinatology, and intensive care. Management should be conducted preferably in high-quality centers experienced in treating this entity, thereby decreasing the great impact of morbidity and mortality associated with SCD in the pregnant population.

How I diagnose and treat venous thromboembolism in sickle cell disease

The incidence of venous thromboembolism (VTE) in adult patients with sickle cell disease (SCD) is high. However, overlapping features between the clinical presentation of VTE and SCD complications and a low index of suspicion for thrombosis can influence patient management decisions. VTE in SCD can therefore present management challenges to the clinical hematologist. Herein, we present 3 distinct clinical vignettes that are representative of our clinical practice with SCD patients. These vignettes are discussed with specific reference to the hypercoagulable state in SCD patients, recent VTE diagnosis and anticoagulant therapy guidelines from the general population, and evaluation of the risk of bleeding as a result of long-term exposure to anticoagulant therapy. We examine current diagnostic and treatment options, highlight limitations of the existing clinical prognostic models that offer personalized guidance regarding the duration of anticoagulation, and propose a clinical approach to guide the decision to extend anticoagulation beyond 3 months.

Sickle cell disease: an inherited thrombophilia

Activation of the hemostatic system occurs in patients with sickle cell disease. The extent to which this activation contributes to sickle cell pathophysiology is uncertain. Clinical trials of anticoagulants or platelet inhibitors have demonstrated the ability to decrease biomarkers of hemostatic activation, but this has generally not resulted in improvement in clinically relevant outcomes. Venous thromboembolism (VTE: deep venous thrombosis and pulmonary embolism) has been until recently an underappreciated complication of sickle cell disease, with incident event and recurrence rates consistent with a strong thrombophilia. There is no strong evidence that management should differ than for other patients with VTE, with the possible exception that secondary prophylaxis be extended regardless of provocation, given the persistent strong thrombophilic state.

Coagulation abnormalities of sickle cell disease: Relationship with clinical outcomes and the effect of disease modifying therapies

Sickle cell disease (SCD) is a hypercoagulable state. Patients exhibit increased platelet activation, high plasma levels of markers of thrombin generation, depletion of natural anticoagulant proteins, abnormal activation of the fibrinolytic system, and increased tissue factor expression, even in the non-crisis "steady state." Furthermore, SCD is characterized by an increased risk of thrombotic complications. The pathogenesis of coagulation activation in SCD appears to be multi-factorial, with contributions from ischemia-reperfusion injury and inflammation, hemolysis and nitric oxide deficiency, and increased sickle RBC phosphatidylserine expression. Recent studies in animal models suggest that activation of coagulation may contribute to the pathogenesis of SCD, but the data on the contribution of coagulation and platelet activation to SCD-related complications in humans are limited. Clinical trials of new generations of anticoagulants and antiplatelet agents, using a variety of clinical endpoints are warranted.

The five key things you need to know to manage adult patients with sickle cell disease

The lack of a strong evidence base to guide the management of adults with sickle cell disease (SCD) makes it difficult for patients to receive high quality care outside of specialty centers. As there is a dearth of providers with sickle cell expertise, the purpose of this article is to identify some of the key things every provider who manages the care of adults with SCD should know. Managing adults with SCD requires excellent clinical skills, as it can affect every organ and cause life-threatening complications but it also requires a willingness to manage patients who often have psychosocial issues that are complex and impact care and care delivery in very significant ways. We have chosen topics for which there is a limited evidence base but which have significant clinical consequences if left unrecognized or poorly managed. The topics that will be addressed include chronic pain, neurocognitive dysfunction, renal disease, venous thromboembolism, and avoiding the inappropriate use of red cell transfusions.

Sickle cell disease and venous thromboembolism in pregnancy and the puerperium

Recent data strongly suggest an increased risk of venous thromboembolism in subjects with sickle cell disease and to a lesser extent, sickle cell trait. However, most studies have been retrospective, case-control or cross-sectional based on data obtained from administrative databases. More data from adequately powered prospective studies that include matched controls are needed to definitely establish the link between venous thromboembolism during pregnancy and sickle hemoglobin disorders. Similarly, there remains a need for properly designed randomized control trials to establish the safety of various hormonal contraceptive methods in women with sickle cell disorders.