Soluble fms-like tyrosine kinase-1 and placental growth factor kinetics during and after pregnancy in women with suspected or confirmed pre-eclampsia

Longitudinal 8-Epi-Prostaglandin F2-Alpha and Angiogenic Profile Mediator Evaluation during Pregnancy in Women with Suspected or Confirmed Pre-eclampsia

Background: In this exploratory study, we aimed to evaluate the dynamics of angiogenic [soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), soluble Endoglin (sEng), and sFlt-1/PlGF, PlGF/sFlt-1, and sEng/PlGF ratios] and oxidative stress [8-epi-prostaglandin F2 alpha (8-epi-PGF2α) and 8-epi-PGF2α/PlGF ratio] mediator levels in women with suspected or confirmed pre-eclampsia (PE) at least two times during pregnancy. We also wanted to identify the possible correlations between 8-epi-PGF2α and angiogenic mediator levels at the time of inclusion of pregnant women. Methods: We included 40 pregnant women with suspected or confirmed PE, with a mean age of 29 years (range between 18 and 41 years) and gestational age between 18 and 28 weeks at inclusion in this study. The Enzyme-Linked Immunosorbent Assay (ELISA) method to measure the levels of serum angiogenic and oxidative stress mediators was used. Results: The evaluation of baseline sFlt-1/PlGF ratios using a cut-off of 38 suggested that 25 pregnant women had a sFlt-1/PlGF ratio of >38 (sFlt-1/PlGF ratio of >38 group) and 15 had a sFlt-1/PlGF ratio of ≤38 (sFlt-1/PlGF ratio of ≤38 group). The increases in sFlt-1/PlGF ratio in the sFlt-1/PlGF ratio of >38 group were caused by both an increase in sFlt-1 (2.04-fold) and a decrease in PlGF levels (2.55-fold). The 8-epi-PGF2α median levels were higher in the sFlt-1/PlGF ratio of >38 group (1.62-fold). During follow-up after pregnancy, we observed that the mean values of sFlt-1 and sEng and the median values of 8-epi-PGF2α and sFlt-1/PlGF, sEng/PlGF, and 8-epi-PGF2α/PlGF ratios increased directly proportional to gestational age for each measurement time until delivery in both groups. For five women who had a sFlt-1/PlGF ratio ≤38 at inclusion, sFlt-1/PlGF ratio was observed to increase to >38 later in pregnancy. We observed that, in the sFlt-1/PlGF ratio >38 group, baseline 8-epi-PGF2α levels better correlated with angiogenic mediator levels. Conclusions: Our study shows that 33.33% of pregnant women evaluated for suspected or confirmed PE with a sFlt-1/PlGF ratio of ≤38 displayed a rise in sFlt-1/PlGF ratio in subsequent weeks. In addition, together with angiogenic mediators, 8-epi-PGF2 α can be utilized as an independent predictor factor to help clinicians identify or predict which pregnant women will develop PE.

Angiogenic imbalance in pre-eclampsia and fetal growth restriction: enhanced soluble fms-like tyrosine kinase-1 binding or diminished production of placental growth factor?

OBJECTIVES

To assess levels of total placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and free PlGF in women with pre-eclampsia (PE) with or without a small-for-gestational-age (SGA) neonate in order to establish whether low free PlGF levels associated with PE and SGA are due to enhanced sFlt-1 binding or decreased PlGF production.

METHODS

This was a secondary analysis of a prospective multicenter cohort study involving 407 pregnancies with suspected or confirmed PE, in which total PlGF levels were calculated from measured sFlt-1 and free PlGF levels. The control group included women who were suspected to have PE at a certain point in pregnancy but did not develop PE. The analysis was stratified according to whether PE was early- or late-onset (gestational age < 34 weeks vs ≥ 34 weeks) and according to the presence of SGA at birth, which was used as a proxy of fetal growth restriction in the absence of Doppler ultrasound and biometric data.

RESULTS

In early-onset PE, both women with and those without SGA had lower free (19 and 45 pg/mL) and total (44 and 100 pg/mL) PlGF levels compared with women without PE (free and total PlGF, 300 and 381 pg/mL, respectively). SGA alone did not affect free and total PlGF in this condition (free and total PlGF, 264 and 352 pg/mL, respectively). Observations in women with late-onset PE were similar, although the changes were more modest. Both SGA (gestational age < 34 weeks) and PE were individually associated with increased sFlt-1 and, in women with both PE and SGA, the upregulation of sFlt-1 occurred in a synergistic manner, thus resulting in the highest sFlt-1/free PlGF ratio in this group. This occurred in both early- and late-onset PE.

CONCLUSIONS

Particularly in pregnancies with early-onset PE and SGA, diminished PlGF production is an important cause of low free PlGF levels. Under such conditions, sFlt-1 lowering is unlikely to restore the angiogenic balance. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Postnatal cardiovascular morbidity following preterm pre-eclampsia: An observational study

OBJECTIVE

To explore the nature of postnatal cardiovascular morbidity following pregnancies complicated by preterm pre-eclampsia and investigate associations between pregnancy characteristics and maternal postnatal cardiovascular function.

STUDY DESIGN

This was an observational sub-study of a single-centre feasibility randomised double-blind placebo-controlled trial (https://www.

CLINICALTRIALS

gov; NCT03466333), involving women with preterm pre-eclampsia, delivering before 37 weeks. Eligible women underwent echocardiography, arteriography and blood pressure monitoring within three days of birth, six weeks and six months postpartum. Correlations between pregnancy and cardiovascular characteristics were assessed using Spearman's correlation.

MAIN OUTCOME MEASURES

The prevalence of cardiovascular dysfunction and remodelling six months following preterm pre-eclampsia.

RESULTS

Forty-four women completed the study. At six months, 27 (61 %) had diastolic dysfunction, 33 (75 %) had raised total vascular resistance (TVR) and 18 (41 %) had left ventricular remodelling. Sixteen (46 %) women had de novo hypertension by six months and only two (5 %) women had a completely normal echocardiogram. Echocardiography did not change significantly from six weeks to six months. Earlier gestation at delivery and lower birthweight centile were associated with worse six-month diastolic dysfunction (E/E': rho = -0.39, p = 0.001 & rho = -0.42, p = 0.005) and TVR (rho = -0.34, p = 0.02 & rho = -0.37, p = 0.01).

CONCLUSIONS

Preterm pre-eclampsia is associated with persistent cardiovascular morbidity-six months postpartum in the majority of women. These cardiovascular changes have significant implications for long-term cardiovascular health. The graded severity of diastolic dysfunction and TVR with worsening pre-eclampsia phenotype suggests a dose-effect. However, the mechanistic link remains uncertain.

The prognostic utility of soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PIGF) biomarkers for predicting preeclampsia: a secondary analysis of data from the INSPIRE trial

Objective

To compare the prognostic performance of biomarkers soluble fms-like tyrosine kinase-1 (sFlt-1), Placental Growth Factor (PIGF), and sFlt-1/PIGF ratio as continuous values or as a binary cut-off of 38 for predicting preeclampsia (PE) within 7 days.

Design

Secondary analysis of a randomised clinical trial.

Setting

Oxford University Hospitals, Oxford, United Kingdom (UK).

Population

Pregnant women between 24⁺⁰ to 37⁺⁰ weeks of gestation with a clinical suspicion of preeclampsia.

Main outcome

Onset of preeclampsia within 7 days of the initial biomarker test.

Methods

Logistic regression model for onset of preeclampsia using: (i) sFlt-1 (ii) PIGF, (iii) sFlt-1/PIGF ratio (continuous), and (iv) sFlt-1/PIGF ratio as a cut-off above or below 38.

Results

Of the total 370 women, 42 (11.3%) developed PE within 7 days of screening. Models with sFlt-1 and sFlt-1/PIGF ratio (continuous) had greater overall performance than models with PIGF or with sFlt-1/PIGF ratio as a cut-off at 38 (R²: sFlt-1 = 55%, PIGF = 38%, sFlt-1/PIGF ratio = 57%, sFlt-1/PIGF ratio as cut-off at 38 model = 46%). The discrimination performance was the highest in sFlt-1 and sFlt-1/PIGF ratio (continuous) (c-statistic, sFlt-1 = 0.94, sFlt-1/PIGF ratio (continuous) = 0.94) models compared to PIGF or sFlt-1/PIGF cut-off models (c-statistic, PIGF = 0.87, sFlt-1/PIGF cut-off = 0.89).

Conclusion

Models using continuous values of sFlt-1 only or sFlt-1/PIGF ratio had better predictive performance compared to a PIGF only or the model with sFlt-1/PIGF ratio as a cut-off at 38. Further studies based on a larger sample size are warranted to substantiate this finding.

A case of preeclampsia developing massive ascites after delivery

We experienced a case of preeclampsia in which massive ascites became apparent in the postpartum period. The patient had isolated proteinuria without hypertension before delivery. The infant had fatal growth restriction and neonatal distress. Massive ascites and isolated proteinuria are important symptoms for predicting the aggravation of PE.

Hematobiochemical variability and predictors of new-onset and persistent postpartum preeclampsia

Preeclampsia (PE) can occur antepartum or postpartum. When it develops de novo after childbirth, it is termed new-onset postpartum PE (NOPPE). Often, antepartum PE disappears after childbirth; however, in some women it persists after childbirth. This form of PE is termed persistent PE (PPE). Thus, there are two forms of postpartum PE: NOPPE and PPE. The pathogenesis and pathophysiology of these diseases have not been fully characterized, and whether NOPPE and PPE are different or similar pathological conditions remains unexplored. Thus, we aimed to compare the haematological and biochemical characteristics of NOPPE and PPE, predict the occurrence of new-onset PE and identify lifestyles that predispose women to postpartum PE. A total of 130 women comprising 65 normotensive postpartum women, 33 NOPPE and 32 PPE women were recruited for this hospital-based case-control study. The socio-demographic and lifestyle characteristics of the participants were obtained through well-structured questionnaires. Haematological and biochemical indices were measured using automated analysers and ELISA. The prevalence of postpartum PE was 11.9%. Dyslipidaemia (p =  < 0.0001), hypomagnesaemia (p =  < 0.001), elevated serum levels of ALT, AST (p =  < 0.0001), sVCAM-1 (p =  < 0.0001) and sFlt-1 (p =  < 0.0001) were more prevalent and severe in the PPE than in the NOPPE. Sedentary lifestyle was common among both groups of hypertensive women. Elevated ALT and AST were significant predictors of NOPPE. These findings indicate that preeclampsia exists after childbirth in a high percentage of women. NOPPE and PPE are different pathological conditions that require different clinical management. Combined glucose, lipid and liver assessment could be useful in predicting postpartum PE.

Should angiogenic markers be included in diagnostic criteria of superimposed pre-eclampsia in women with chronic hypertension?

OBJECTIVE

Although the most recent guidance from the International Society for the Study of Hypertension in Pregnancy (ISSHP) has highlighted the role of angiogenic marker assessment in the diagnosis of pre-eclampsia (PE) in women with chronic hypertension, the ISSHP has withheld recommending its implementation due to the limited available evidence in this group of women. Therefore, we aimed to investigate the value of soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) assessment in women with chronic hypertension and suspected superimposed PE.

METHODS

This was a retrospective analysis of prospectively collected data recorded in an electronic database between January 2013 and October 2019. Women with chronic hypertension and singleton pregnancy who had suspected superimposed PE were included. Superimposed PE was suspected in women presenting with worsening hypertension, epigastric pain, new-onset edema, dyspnea or neurological symptoms. The exclusion criteria were delivery within 1 week after assessment for reasons other than PE, chronic kidney disease, history of cardiac disease, fetal aneuploidy, genetic syndrome or major structural anomaly and missing pregnancy outcome. Maternal serum angiogenic markers (sFlt-1, PlGF and sFlt-1/PlGF ratio) were measured. The primary outcome was the utility of angiogenic markers in the prediction of superimposed PE. Predictive accuracy was assessed for superimposed PE diagnosed at different timepoints, including within 1 week after assessment and any time before birth. The secondary outcome was comparison of adverse maternal and perinatal outcomes between women with superimposed PE diagnosed according to the traditional ISSHP criteria and those diagnosed according to extended criteria including angiogenic markers. The predictive accuracy of each angiogenic marker was assessed using receiver-operating-characteristics-curve analysis. Area under the curve (AUC) values were compared using De Long's test. A sensitivity analysis was planned for gestational age at assessment. The association of various variables with composite adverse maternal and perinatal outcomes was assessed using binomial regression.

RESULTS

The study included 142 pregnant women with chronic hypertension and suspected superimposed PE, of whom 25 (17.6%) developed PE within 1 week after assessment, 52 (36.6%) developed PE at any timepoint before birth and 90 (63.4%) delivered without PE. Maternal serum angiogenic imbalance was associated significantly with superimposed PE diagnosed according to the ISSHP criteria within 1 week or at any time after assessment (P < 0.001 for both). The predictive accuracy of maternal serum sFlt-1/PlGF ratio for superimposed PE diagnosed within 1 week after assessment was superior to that of maternal serum PlGF level (AUC, 0.91 vs 0.86; P = 0.032). The addition of angiogenic imbalance to the traditional ISSHP diagnostic criteria was associated with an increase in the detection rate (35.1% increase; 95% credible interval (CrI), 16.6-53.6%) and positive (9.6% increase; 95% CrI, 0.0-20.6%) and negative (3.1% increase; 95% CrI, 1.3-4.9%) predictive values for composite adverse maternal outcome, with high posterior probabilities of an increase in each predictive accuracy parameter (> 99.9%, 95.6% and > 99.9%, respectively), without a meaningful decrease in specificity. The addition of angiogenic imbalance improved the detection rate for composite adverse perinatal outcome (20.6% increase; 95% CrI, 0.0-42.2%), with a high posterior probability (96.9%). There was a corresponding drop in specificity (5.7% decrease; 95% CrI, -2.3% to 13.6%), with a posterior probability of 91.8%.

CONCLUSIONS

In women with chronic hypertension and suspected superimposed PE, addition of maternal serum angiogenic markers to the traditional diagnostic criteria for superimposed PE improved significantly the sensitivity for the prediction of both maternal and perinatal adverse outcomes. Implementation of angiogenic marker assessment in the evaluation of pregnant women with chronic hypertension should therefore be considered. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Placental Trophoblast Specific Overexpression of Chemerin Induces Preeclampsia-like Symptoms

Maternal circulating levels of the adipokine chemerin are elevated in preeclampsia, but its origin and contribution to preeclampsia remain unknown. We therefore studied 1) placental chemerin expression and release in human pregnancy, and 2) the consequences of chemerin overexpression via lentivirus-mediated trophoblast-specific gene manipulation in both mice and immortalized human trophoblast. Placental chemerin expression and release were increased in women with preeclampsia, and their circulating chemerin levels correlated positively with the soluble Fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor ratio, a well-known biomarker of preeclampsia severity. Placental trophoblast chemerin overexpression in mice induced a preeclampsia-like syndrome, involving hypertension, proteinuria, and endotheliosis, combined with diminished trophoblast invasion, a disorganized labyrinth layer, and upregulation of sFlt-1 and the inflammation markers nuclear factor-kappa B, tumor necrosis factor-α and interleukin-1β. It also led to embryo resorption, while maternal serum chemerin levels correlated negatively with fetal weight in mice. Chemerin overexpression in human trophoblasts upregulated sFlt-1, reduced vascular endothelial factor-A, and inhibited migration and invasion, as well as tube formation during co-culture with human umbilical vein endothelial cells. The chemokine-like receptor 1 (CMKLR1) antagonist α-NETA prevented the latter phenomena, although it did not reverse the chemerin-induced downregulation of the phosphoinositide 3-kinase/Akt pathway. In conclusion, upregulation of placental chemerin synthesis disturbs normal placental development via its CMKLR1 receptor, thereby contributing to fetal growth restriction/resorption and the development of preeclampsia. Chemerin might be a novel biomarker of preeclampsia, and inhibition of the chemerin/CMKLR1 pathway is a promising novel therapeutic strategy to treat preeclampsia.

Postpartum preeclampsia or eclampsia: defining its place and management among the hypertensive disorders of pregnancy

High blood pressure in the postpartum period is most commonly seen in women with antenatal hypertensive disorders, but it can develop de novo in the postpartum time frame. Whether postpartum preeclampsia or eclampsia represents a separate entity from preeclampsia or eclampsia with antepartum onset is unclear. Although definitions vary, the diagnosis of postpartum preeclampsia should be considered in women with new-onset hypertension 48 hours to 6 weeks after delivery. New-onset postpartum preeclampsia is an understudied disease entity with few evidence-based guidelines to guide diagnosis and management. We propose that new-onset hypertension with the presence of any severe features (including severely elevated blood pressure in women with no history of hypertension) be referred to as postpartum preeclampsia after exclusion of other etiologies to facilitate recognition and timely management. Older maternal age, black race, maternal obesity, and cesarean delivery are all associated with a higher risk of postpartum preeclampsia. Most women with delayed-onset postpartum preeclampsia present within the first 7 to 10 days after delivery, most frequently with neurologic symptoms, typically headache. The cornerstones of treatment include the use of antihypertensive agents, magnesium, and diuresis. Postpartum preeclampsia may be associated with a higher risk of maternal morbidity than preeclampsia with antepartum onset, yet it remains an understudied disease process. Future research should focus on the pathophysiology and specific risk factors. A better understanding is imperative for patient care and counseling and anticipatory guidance before hospital discharge and is important for the reduction of maternal morbidity and mortality in the postpartum period.

Model for Early Prediction of Preeclampsia: A Nested Case Controlled Study in Indian Women

Purpose

Preeclampsia (PE) affects 5-7% of the pregnancies worldwide, and is one of the most dreaded disorders of pregnancy contributing to maternal and neonatal mortality. PE is mostly presented in the third trimester of pregnancy. Here, we used serum placental growth factor (PIGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) to develop a model for predicting PE in Indian women in early second trimester.

Methods

In this case-control study, a total 1452 healthy pregnant women were recruited. Blood samples were collected at the following gestational weeks (GWs), 12-20 (GW1), 21-28 (GW2) and 29-term (GW3), and post-delivery. Body mass index (BMI) was calculated by anthropometric measurements. Serum sFlt-1, PIGF and VEGF were analyzed by ELISA. A predictive model for PE was developed using multivariable logistic regression analysis.

Results

In PE cases, serum PlGF and VEGF levels were significantly lower at each GW, while serum sFlt-1 was lower only at GW1, relative to age-matched controls, (n = 132/group). Age-matched comparison between PE cases and controls indicated that sFlt-1 was associated with decreased PE outcome (Odds ratio. OR = 0.988, CI = 0.982-0.993), whereas sFlt-1/PlGF ratio (OR = 1.577, CI = 1.344-1.920) and BMI (OR = 1.334, CI = 1.187-1.520) were associated with increased PE outcome. Logistic regression was used to develop a predictive model for PE at GW1. Using testing dataset, model was externally validated which resulted in 88% accuracy in predicting PE cases at 0.5 probability cutoff.

Conclusion

Prediction model using sFlt-1, sFlt-1/PlGF ratio and BMI may be useful to predict PE as early as 12-20 weeks in women with optimal sensitivity and specificity.

Administration of recombinant human placental growth factor decreases blood pressure in obese hypertensive pregnant rats

OBJECTIVES

Although epidemiological studies have shown that obesity is associated with increased incidence of hypertension during pregnancy, the mechanisms linking these two comorbidities are not as well studied. Previous investigations detected lower levels of the anti-hypertensive and pregnancy-related factor, placental growth factor (PlGF), in obese hypertensive pregnancies. Therefore, we examined whether obese hypertensive pregnant rats have reduced PlGF and whether increasing its levels by administering recombinant human (rh)PlGF reduces their blood pressure.

METHODS

We utilized a genetic model of obesity characterized to be heavier, hypertensive and fertile, namely rats having heterozygous deficiency of the melanocortin-4 receptor (MC4R-def).

RESULTS

MC4R-def obese rats had lower circulating levels of PlGF than wild-type lean controls at gestational day 19. Also, assessment of the PlGF receptor, Flt-1, in the vasculature showed that its levels were reduced in aorta and kidney glomeruli but increased in small mesenteric arteries. Chronic intraperitoneal administration of rhPlGF from gestational day 13-19 significantly increased circulating PlGF levels in both obese and lean rats, but reduced blood pressure only in the obese pregnant group. The rhPlGF treatment did not alter maternal body and fat masses or circulating levels of the adipokines, leptin and adiponectin. In addition, this treatment did not impact average foetal weights but increased placental weights regardless of obese or lean pregnancy.

CONCLUSION

PlGF is reduced in MC4R-def obese hypertensive pregnant rats, which is similar to findings in obese hypertensive pregnant women, while increasing its levels with exogenous rhPlGF reduces their blood pressure.

A Review of Research Progress of Pregnancy with Twins with Preeclampsia

Preeclampsia has a significant long-term effect on the health of both mothers and babies. Preeclampsia-related pregnancy complications increase the morbidity and mortality of pregnant women and their fetuses by 5-8%. The recent advancement of assisted reproductive technology, combined with a rise in the number of elderly pregnant women, has resulted in pregnancy incidence with twins. Twins pregnant women have a 2-3 times greater risk of developing preeclampsia than singleton pregnant women, and it happens sooner and progresses faster. It is more severe and may appear in an atypical way. End-organ damage, such as renal failure, stroke, cardiac arrest, pulmonary edema, placental abruption, and cesarean section, are related maternal complications. Fetal growth retardation, stillbirth, and premature delivery with obstetric signs are all fetal complications. According to studies, all multiple pregnancies can take low-dose aspirin (60-150 mg) to minimize the risk of preeclampsia. To improve pregnancy outcomes and reduce the inherent risk of pregnancy with twins, twins should be handled as a high-risk pregnancy and treated differently than singletons. The literature on twin pregnancy with preeclampsia is the subject of this review. It will examine the current state of research on preeclampsia in pregnancy with twins, including the occurrence, diagnosis, and pathophysiological process. Moreover, the effect of pregnancy with twins on the perinatal outcome and pregnancy management of pregnancy with twins, including blood pressure management and preeclampsia prevention and treatment, is examined in this literature review. The goal is to figure out what kind of diagnosis and care you may need.

The sFlt-1 to PlGF Ratio in Pregnant Women with Rheumatoid Arthritis: Impact of Disease Activity and Sulfasalazine Use

OBJECTIVES

An elevated sFlt-1/PlGF-ratio has been validated as a significant predictor of preeclampsia, but has not been established in women with rheumatoid arthritis (RA). We explored whether the sFlt-1/PlGF-ratio could be altered due to disease activity in RA, and could be applied in this population to predict preeclampsia. Since sulfasalazine has been suggested to improve the angiogenic imbalance in preeclampsia, we also aimed to examine whether sulfasalazine could affect sFlt-1 or PlGF levels.

METHODS

Making use of a nationwide, observational, prospective cohort study on pregnant women with RA, sFlt-1 and PlGF were measured in the third trimester. A total of 221 women, aged 21-42 years, were included, with a median gestational age of 30 + 3 weeks.

RESULTS

No differences in sFlt-1 or PlGF were observed between women with high, intermediate or low disease activity (p= 0.07 and p= 0.41), whereas sFlt-1 and PlGF did not correlate with DAS28-CRP score (r=-0.01 and r=-0.05, respectively). Four (2%) women with a sFlt-1/PlGF-ratio ≤38 developed preeclampsia in comparison to three (43%) women with a ratio > 38, corresponding to a negative predictive value of 98.1%. Sulfasalazine users (n = 57) did not show altered levels of sFlt-1 or PlGF in comparison to non-sulfasalazine users (n = 164, p= 0.91 and p= 0.11).

CONCLUSION

Our study shows that in pregnant women with RA, the sFlt-1/PlGF-ratio is not altered due to disease activity and a cut-off ≤38 can be used to exclude preeclampsia. Additionally, sulfasalazine use did not affect sFlt-1 or PlGF levels in this population.

Maternal Serum Inhibin-A Augments the Value of Maternal Serum PlGF and of sFlt-1/PlGF Ratio in the Prediction of Preeclampsia and/or FGR Near Delivery—A Secondary Analysis

Objective: We previously provided evidence to confirm that maternal serum levels of soluble Fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), and their ratio are useful tools to direct the management of preeclampsia (PE), fetal growth restriction (FGR), and PE+FGR near delivery. In this secondary analysis, we further examine the potential additive value of maternal serum Inhibin-A, which is a hormone marker of the transforming growth factor family, to the accuracy provided by maternal serum PlGF and sFlt-1. Methods: We conducted a secondary analysis where we extracted the data of a cohort of 125 pregnant women enrolled near delivery at the clinics of the University Medical Center of Ljubljana, Slovenia. The dataset included 31 cases of PE, 16 of FGR, 42 of PE+FGR, 15 preterm delivery (PTD), and 21 unaffected controls with delivery of a healthy baby at term. Cases delivered before 34 weeks’ gestation included 10 of PE, 12 of FGR, 28 of PE+FGR, and 6 of PTD. In addition to the recorded demographic characteristics and medical history and the maternal serum levels of PlGF and sFlt-1/PlGF ratio, which were previously published, we evaluated the added value of maternal serum Inhibin-A. The predictive accuracy of each biomarker, their ratios, and combinations were estimated from areas under the curve (AUC) of receiver operating characteristics (ROC) curves, Box and Whisker plots, and by multiple regression. We estimated accuracy by the continuous marker model and a cutoff model. Results: In this study, we combined Inhibin-A with PlGF or with the sFlt-1/PlGF ratio and showed a 10–20% increase in AUCs and 15–45% increase in the detection rate, at 10% false positive rate, of PE, and a lower, but significant, increase for PE+FGR and FGR in all cases but not for FGR in early cases delivered < 34 weeks. The use of a cutoff model was adequate, although a bit higher accuracy was obtained from the continuous model. The highest correlation was found for PlGF with all three complications. Conclusion: In this secondary analysis, we have found that maternal serum Inhibin-A improves the accuracy of predicting PE and PE+FGR provided by maternal serum angiogenic markers alone, bringing the results to a diagnostic level; thus, it could be considered for directing clinical management. Inhibin-A had smaller or no added value for the accuracy of predicting FGR alone, mainly of early cases delivered <34 weeks.

Long-Term Postpartum Cardiac Function and Its Association With Preeclampsia

Background

Preeclampsia is a prominent risk factor for long‐term development of cardiovascular disease. Although existing studies report a strong correlation between preeclampsia and heart failure, the underlying mechanisms are poorly understood. One possibility is the glycoprotein growth factor activin A. During pregnancy, elevated activin A levels are associated with impaired cardiac global longitudinal strain at 1 year, but whether these changes persist beyond 1 year is not known. We hypothesized that activin A levels would remain increased more than 1 year after a preeclamptic pregnancy and correlate with impaired cardiac function.

Methods and Results

To test our hypothesis, we performed echocardiograms and measured activin A levels in women approximately 10 years after an uncomplicated pregnancy (n=25) or a pregnancy complicated by preeclampsia (n=21). Compared with women with a previously normal pregnancy, women with preeclampsia had worse global longitudinal strain (−18.3% versus −21.3%, P=0.001), left ventricular posterior wall thickness (0.91 mm versus 0.80 mm, P=0.003), and interventricular septal thickness (0.96 mm versus 0.81 mm, P=0.0002). Women with preeclampsia also had higher levels of activin A (0.52 versus 0.37 ng/mL, P=0.02) and activin/follistatin‐like 3 ratio (0.03 versus 0.02, P=0.04). In a multivariable model, the relationship between activin A levels and worsening global longitudinal strain persisted after adjusting for age at enrollment, mean arterial pressure, race, and body mass index (P=0.003).

Conclusions

Our findings suggest that both activin A levels and global longitudinal strain are elevated 10 years after a pregnancy complicated by preeclampsia. Future studies are needed to better understand the relationship between preeclampsia, activin A, and long‐term cardiac function.

PAPP-A2 and Inhibin A as Novel Predictors for Pregnancy Complications in Women With Suspected or Confirmed Preeclampsia

Background We aimed to evaluate the value of inhibin A and PAPP-A2 (pregnancy-associated plasma protein-A2) as novel biomarkers in the prediction of preeclampsia-related complications and how they compare with angiogenic biomarkers. Methods and Results Making use of a secondary analysis of a prospective, multicenter, observational study, intended to evaluate the usefulness of sFlt-1 (soluble Fms-like tyrosine kinase-1)/PlGF (placental growth factor) ratio, we measured inhibin A and PAPP-A2 levels in 524 women with suspected/confirmed preeclampsia. Women had a median gestational age of 35 weeks (range, 20-41 weeks) while preeclampsia occurred in 170 (32%) women. Levels of inhibin A and PAPP-A2 were significantly increased in women with preeclampsia and in maternal perfusate of preeclamptic placentas. Inhibin A and PAPP-A2 (C-index = 0.73 and 0.75) significantly improved the prediction of maternal complications when added on top of the traditional criteria; gestational age, parity, proteinuria, and diastolic blood pressure (C-index = 0.60). PAPP-A2 was able to improve the C-index from 0.75 to 0.77 when added on top of the sFlt-1/PlGF ratio for the prediction of maternal complications. To discriminate fetal/neonatal complications on top of traditional criteria, inhibin A and PAPP-A2 showed additive value (C-index = 0.79 to 0.80 and 0.82, respectively) but their discriminative ability remained inferior to that of sFlt-1/PlGF ratio or PlGF. Interestingly, the PAPP-A2/PlGF ratio alone showed remarkable value to predict pregnancy complications, being superior to sFlt-1/PlGF ratio in the case of maternal complications. Conclusions Inhibin A and PAPP-A2 show significant potential to predict preeclampsia-related pregnancy complications and might prove beneficial on top of the angiogenic markers.

SARS-COV-2 infection during pregnancy, a risk factor for eclampsia or neurological manifestations of COVID-19? Case report

BACKGROUND

There are no published cases of tonic-clonic seizures and posterior bilateral blindness during pregnancy and Severe Acute Respiratory Syndrome (SARS) Coronavirus (COV) 2 (SARS-COV-2) infection. We do not just face new and unknown manifestations, but also how different patient groups are affected by SARS-COV-2 infection, such as pregnant women. Coronavirus Disease 2019 (COVID-19), preeclampsia, eclampsia and posterior reversible leukoencephalopathy share endothelium damage and similar pathophysiology.

CASE PRESENTATION

A 35-year-old pregnant woman was admitted for tonic-clonic seizures and SARS-COV-2 infection. She had a normal pregnancy control and no other symptoms before tonic-clonic seizures development. After a Caesarean section (C-section) she developed high blood pressure, and we initiated antihypertensive treatment with labetalol, amlodipine and captopril. Few hours later she developed symptoms of cortical blindness that resolved in 72 h with normal brain computed tomography (CT) angiography.

CONCLUSION

The authors conclude that SARS COV-2 infection could promote brain endothelial damage and facilitate neurological complications during pregnancy.

C-allele of rs4769613 Near FLT1 Represents a High-Confidence Placental Risk Factor for Preeclampsia

The variant rs4769613 T/C within the enhancer element near FLT1, an acknowledged gene in preeclampsia, was previously identified as a risk factor for preeclampsia in the genome-wide association study (GWAS) targeting placental genotypes. We aimed to test the robustness of this association in 2 Estonian cohorts. Both placental sample sets HAPPY PREGNANCY (Development of novel non-invasive biomarkers for fertility and healthy pregnancy; preeclampsia, n=44 versus nonpreeclampsia, n=1724) and REPROMETA (REPROgrammed fetal and/or maternal METAbolism; 52/277) exhibited suggestive association between rs4769613[C] variant and preeclampsia (logistic regression adjusted for gestational age and fetal sex, nominal P<0.05). Meta-analysis across 2 samples (96/2001) replicated the genome-wide association study outcome (Bonferroni corrected P=4×10^-3; odds ratio, 1.75 [95% CI, 1.23-2.49]). No association was detected with gestational diabetes mellitus, preterm birth, and newborn parameters. Also, neither maternal nor paternal rs4769613 genotypes predisposed to preeclampsia. The exact role of placental rs4769613 genotype in the preeclampsia pathogenesis is to be clarified as no effect was detected on maternal baseline serum sFlt-1 (soluble fms-related receptor tyrosine kinase 1) levels. However, when placental FLT1 gene expression and maternal serum sFlt-1 measurements were stratified by placental rs4769613 genotypes, significantly higher transcript and biomarker levels were detected in preeclampsia versus nonpreeclampsia cases in the CC- and CT- (Student t test, P≤0.02), but not in the TT-genotype subgroup. We suggest that rs4769613 represents a conditional expression Quantitative Trait Locus, whereby only the enhancer with the C-allele reacts to promote the FLT1 expression in unfavorable placental conditions. The study highlighted that the placental FLT1 rs4769613 C-allele is a preeclampsia-specific risk factor. It may contribute to early identification of high-risk women, for example, when genotyped in the cffDNA available in maternal blood plasma.

Added prognostic value of longitudinal changes of angiogenic factors in early-onset severe pre-eclampsia: a prospective cohort study

OBJECTIVE

To assess in women with early-onset severe pre-eclampsia whether longitudinal changes in angiogenic factors improve the prediction of adverse outcome.

DESIGN

Prospective cohort study.

SETTING

Maternity units in two Spanish hospitals.

POPULATION

Women with diagnosis of early-onset severe pre-eclampsia.

METHODS

Levels of placental growth factor (PlGF), soluble fms-like tyrosine kinase (sFlt-) and sFlt-1/PlGF ratio were measured at admission and before delivery, and average daily change calculated. The association of longitudinal changes of angiogenic factors with the time interval to delivery and with complications was evaluated by logistic and Cox regression.

MAIN OUTCOME MEASURES

Interval to delivery and composite of adverse outcomes.

RESULTS

We included 63 women, of which 26 (41.3%) had a complication. Longitudinal changes of sFlt-1 were more pronounced in complicated pregnancies (median: 1047 versus 342 pg/ml/day; P = 0.04). On the multivariate analysis, the clinical risk score and sFlt-1 at admission explained 6.2% of the uncertainty for complication; the addition of sFlt-1 longitudinal changes improved this to 25.3% (P = 0.002). The median time from admission to delivery was 4 days (95% CI 1.6-6.04) in those in the highest quartile of sFlt-1 longitudinal changes versus 16 days (95% CI 12.4-19.6) in the remaining women (Log-rank test P < 0.001).

CONCLUSIONS

Longitudinal changes in sFlt-1 maternal levels from admission for confirmed early-onset severe pre-eclampsia add to baseline characteristics in the prediction of adverse outcome and interval to delivery.

TWEETABLE ABSTRACT

In early-onset severe pre-eclampsia, longitudinal changes in sFlt-1 levels improve the prediction of complications and interval to delivery.

Human Placental Vascular Reactivity in Health and Disease: Implications for the Treatment of Pre-eclampsia

Adequate development of the placenta is essential for optimal pregnancy outcome. Pre-eclampsia (PE) is increasingly recognized to be a consequence of placental dysfunction and can cause serious maternal and fetal complications during pregnancy. Furthermore, PE increases the risk of neonatal problems and has been shown to be a risk factor for cardiovascular disease of the mother later in life. Currently, there is no adequate treatment for PE, mainly because its multifactorial pathophysiology remains incompletely understood. It originates in early pregnancy with abnormal placentation and involves a cascade of dysregulated systems in the placental vasculature. To investigate therapeutic strategies it is essential to understand the regulation of vascular reactivity and remodeling of blood vessels in the placenta. Techniques using human tissue such as the ex vivo placental perfusion model provide insight in the vasoactive profile of the placenta, and are essential to study the effects of drugs on the fetal vasculature. This approach highlights the different pathways that are involved in the vascular regulation of the human placenta, changes that occur during PE and the importance of focusing on restoring these dysfunctional systems when studying treatment strategies for PE.

A Systematic Review of Vascular Structure and Function in Pre-eclampsia: Non-invasive Assessment and Mechanistic Links

Hypertensive disorders of pregnancy, such as pre-eclampsia, are known to be independently associated with the development of premature cardiovascular disease (CVD) in women. In pre-eclampsia, the placenta secretes excess anti-angiogenic factors into the maternal circulation, leading to widespread endothelial damage, and inflammation. This endothelial damage is evidenced to persist beyond the acute illness. However, whether it is permanent and responsible for the elevated rates of premature CVD seen in this at-risk group remains unclear. A systematic review of the available literature with respect to vascular structure and function prior to, during and after a pregnancy complicated by pre-eclampsia was performed. Studies non-invasively assessing vascular structure using carotid intima-media thickness (CIMT), retinal microvasculature caliber, CT coronary angiogram, or coronary calcium scores were included. Vascular function was assessed using brachial flow-mediated dilation (FMD), pulse wave analysis (PWA), and peripheral arterial tonometry (PAT). In total 59 articles were included (13 CIMT, 5 CTCA/Ca score, five retinal microvasculature, 27 FMD, 7 PAT, and 14 PWV/PWA), consisting of prospective and retrospective cohort, and case-control studies. Change in vascular structure was evidenced with significant increases in CIMT by 73-180 μm greater than that of non-affected women. This is tempered by other studies reporting resolution of structural changes postpartum, highlighting the need for further research. Accelerated coronary calcification and plaque deposition was identified, with greater rates of increased calcium scores and subclinical coronary artery disease shown by CTCA in women with a history of pre-eclampsia at 30 years postpartum. Impaired endothelial function was consistently reported prior to, during and immediately after pregnancy as evidenced by differences in FMD of 1.7-12.2% less than non-affected women, an increase in PWV by 13.2-26%, and reduced retinal microvascular caliber and arterial elasticity indices. The evidence was less conclusive for the persistence of long-term endothelial dysfunction. Understanding the underlying mechanistic links between pre-eclampsia and CVD is a key step to identifying targeted therapies aimed at "repairing the endothelium" and attenuating risk. This review has highlighted the need for a greater understanding of vascular structure and function following pre-eclampsia through high quality studies with large sample sizes, particularly in the longer postpartum period when clinical CVD disease starts to manifest.

A Systematic Review of Vascular Structure and Function in Pre-eclampsia: Non-invasive Assessment and Mechanistic Links

Hypertensive disorders of pregnancy, such as pre-eclampsia, are known to be independently associated with the development of premature cardiovascular disease (CVD) in women. In pre-eclampsia, the placenta secretes excess anti-angiogenic factors into the maternal circulation, leading to widespread endothelial damage, and inflammation. This endothelial damage is evidenced to persist beyond the acute illness. However, whether it is permanent and responsible for the elevated rates of premature CVD seen in this at-risk group remains unclear. A systematic review of the available literature with respect to vascular structure and function prior to, during and after a pregnancy complicated by pre-eclampsia was performed. Studies non-invasively assessing vascular structure using carotid intima-media thickness (CIMT), retinal microvasculature caliber, CT coronary angiogram, or coronary calcium scores were included. Vascular function was assessed using brachial flow-mediated dilation (FMD), pulse wave analysis (PWA), and peripheral arterial tonometry (PAT). In total 59 articles were included (13 CIMT, 5 CTCA/Ca score, five retinal microvasculature, 27 FMD, 7 PAT, and 14 PWV/PWA), consisting of prospective and retrospective cohort, and case-control studies. Change in vascular structure was evidenced with significant increases in CIMT by 73–180 μm greater than that of non-affected women. This is tempered by other studies reporting resolution of structural changes postpartum, highlighting the need for further research. Accelerated coronary calcification and plaque deposition was identified, with greater rates of increased calcium scores and subclinical coronary artery disease shown by CTCA in women with a history of pre-eclampsia at 30 years postpartum. Impaired endothelial function was consistently reported prior to, during and immediately after pregnancy as evidenced by differences in FMD of 1.7–12.2% less than non-affected women, an increase in PWV by 13.2–26%, and reduced retinal microvascular caliber and arterial elasticity indices. The evidence was less conclusive for the persistence of long-term endothelial dysfunction. Understanding the underlying mechanistic links between pre-eclampsia and CVD is a key step to identifying targeted therapies aimed at “repairing the endothelium” and attenuating risk. This review has highlighted the need for a greater understanding of vascular structure and function following pre-eclampsia through high quality studies with large sample sizes, particularly in the longer postpartum period when clinical CVD disease starts to manifest.

Abnormal expression and clinical significance of 25-hydroxyvitamin D and sFlt-1 in patients with preeclampsia

Objective

To determine the association between levels of serum 25-hydroxyvitamin D (25[OH]D) and soluble fms-like tyrosine kinase 1 (sFlt-1) in patients with preeclampsia.

Methods

Clinical and demographic data were collected from patients with preeclampsia and healthy pregnant controls. Serum 25(OH)D and sFlt-1 levels were evaluated by enzyme-linked immunosorbent assay and their correlations were determined using Spearman’s rank correlation coefficient. Associations between serum 25(OH)D and sFlt-1 levels and disease severity and clinical parameters were evaluated.

Results

Significantly lower serum 25(OH)D and higher sFlt-1 levels were observed in patients with preeclampsia (n = 100) versus controls (n = 100), and 25(OH)D was inversely correlated with sFlt-1 in patients with preeclampsia. Serum 25(OH)D levels were reduced, while sFlt-1 concentration was increased in patients with severe versus mild preeclampsia. Serum 25(OH)D levels were reduced in late-onset versus early-onset severe preeclampsia. Patients with preeclampsia who had lower serum 25(OH)D or elevated sFlt-1 levels showed significantly higher blood pressure indexes versus those with higher 25(OH)D or lower sFlt-1.

Conclusions

Low serum 25(OH)D and high sFlt-1 may be candidate biomarkers for preeclampsia diagnosis and prognosis.

Preeclampsia: Maternal Systemic Vascular Disorder Caused by Generalized Endothelial Dysfunction Due to Placental Antiangiogenic Factors

Preeclampsia, a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, is the leading cause of maternal and perinatal morbidity and mortality. Maternal endothelial dysfunction caused by placental factors has long been accepted with respect to the pathophysiology of preeclampsia. Over the past decade, increased production of placental antiangiogenic factors has been identified as a placental factor leading to maternal endothelial dysfunction and systemic vascular dysfunction. This review summarizes the recent advances in understanding the molecular mechanisms of endothelial dysfunction caused by placental antiangiogenic factors, and the novel clinical strategies based on these discoveries.

Pilot study: placental biomarker predictive capability (sFlt-1, PlGF and their ratio) of postpartum maternal outcome

BACKGROUND

Prenatal measurement of placental biomarkers was able to improve screening and diagnosis of preeclampsia. Little is known about the clinical role of placental biomarkers in the postpartum period.

METHODS

This study is a prospective monocentric trial that included a total of 30 women with preeclamptic pregnancies. Serum placental biomarkers including soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) were measured before and 2 h after delivery by Enzyme-Linked Immunosorbent Assay (ELISA) using commercially available kits according to manufacturer's instructions and correlated with the postpartum outcome.

RESULTS

Postpartum higher serum PlGF level was associated with postpartum elevation of the systolic blood pressure. Yet, the placental biomarkers were not able to predict general worsening of postpartum preeclampsia or other individual clinical or laboratory parameters.

CONCLUSION

Serum concentrations of sFlt-1 and PlGF or their ratio in our study cohort did not completely predict the occurrence of postpartum preeclampsia. Yet, postpartum higher serum PlGF level was associated with postpartum elevation of the systolic blood pressure.

An updated view on the origin and use of angiogenic biomarkers for preeclampsia

Introduction: The last decade has seen massive efforts towards the identification and the potential use of predictive biomarkers for the pregnancy pathology preeclampsia. The angiogenic factors sFlt-1 and placental growth factor (PGF) have been in focus and have been massively supported. Areas covered: This review describes preeclampsia and intra-uterine growth restriction (IUGR), focusing on sFlt-1 and PGF, their sources during and outside pregnancy and the application of these markers in diseases outside pregnancy. Finally, the specificity of the angiogenic markers for preeclampsia is discussed. Expert commentary: The admixture of the two independent syndromes preeclampsia and IUGR has not helped in identifying the etiologies of either. Rather, it has made the search for new markers and pathways much more complicated as has the constriction on the angiogenic markers. The current markers sFlt-1 and PGF have a clear value once an adverse outcome is diagnosed but are not specific for preeclampsia. Also, they are mostly derived from the maternal vascular system rather than the placenta and are already in use as markers outside pregnancy. A new holistic approach using disease maps and interoperable workflows based on topic-related big data will help in broadening our understanding of the etiology of preeclampsia and hence, develop new markers and therapies.