Chronic hypertension in pregnancy: impact of ethnicity and superimposed preeclampsia on placental, endothelial, and renal biomarkers

Risk Factors for Early- and Late-Onset Superimposed Preeclampsia

OBJECTIVE

 Risk factors of early- and late-onset preeclampsia among pregnant individuals with chronic hypertension are not well described in the literature. We hypothesized that early- and late-onset superimposed preeclampsia (SIPE) have different risk factors. Therefore, we aimed to examine the risk factors of early- and late-onset SIPE among individuals with chronic hypertension.

STUDY DESIGN

 This was a retrospective case-control study of pregnant individuals with chronic hypertension who delivered at 22 weeks' gestation or greater at an academic institution. Early-onset SIPE was defined as SIPE diagnosed before 34 weeks' gestation. To identify risk factors, we compared individuals' characteristics between individuals who developed early- and late-onset SIPE and those who did not. We then compared characteristics between individuals who developed early-onset SIPE and late-onset SIPE. Characteristics with p-values of less than 0.05 by bivariable variables were analyzed by simple and multivariable logistic regression models to calculate crude and adjusted odds ratios (aOR) and 95% confidence intervals (95% CI). Missing values were imputed with multiple imputation.

RESULTS

 Of 839 individuals, 156 (18.6%) had early-onset, 154 (18.4%) had late-onset SIPE and 529 (63.1%) did not have SIPE. The multivariate logistic regression model showed that serum creatinine ≥ 0.7 mg/dL compared to less than 0.7 mg/dL (aOR: 2.89 [95% CI: 1.63-5.13]), increase of creatinine (1.33 [1.16-1.53]), nulliparity compared to multiparity (1.77 [1.21-2.60]), and pregestational diabetes (1.70 [1.11-2.62]) were risk factors for early-onset SIPE. The multivariate logistic regression model showed that nulliparity compared to multiparity (1.53 [1.05-2.22]) and pregestational diabetes (1.74 [1.14-2.64]) was a risk factor for late-onset SIPE. Serum creatinine ≥ 0.7 mg/dL (2.90 [1.36-6.15]) and increase of creatinine (1.33 [1.10-1.60]) were significantly associated with early-onset SIPE compared to late-onset SIPE.

CONCLUSION

 Kidney dysfunction seemed to be associated with the pathophysiology of early-onset SIPE. Nulliparity and pregestational diabetes were common risk factors for both early- and late-onset SIPE.

KEY POINTS

· Serum creatinine level was positively associated with early-onset superimposed preeclampsia (SIPE).. · Pregestational diabetes and nulliparity were associated with both early- and late-onset SIPE.. · The identification of risk factors may provide an opportunity to decrease the rates of SIPE..

Racial and Ethnic Disparities among Pregnancies with Chronic Hypertension and Adverse Outcomes

OBJECTIVE

 We aimed to ascertain whether the risk of adverse pregnancy outcomes in the United States among individuals with chronic hypertension differed by maternal race and ethnicity and to assess the temporal trend.

STUDY DESIGN

 Population-based retrospective study using the U.S. Vital Statistics datasets evaluated pregnancies with chronic hypertension, singleton live births that delivered at 24 to 41 weeks. The coprimary outcomes were a composite maternal adverse outcome (preeclampsia, primary cesarean delivery, intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy) and a composite neonatal adverse outcome (preterm birth, small for gestational age, Apgar's score <5 at 5 minutes, assisted ventilation> 6 hours, seizure, or death). Multivariable Poisson regression models were used to estimate adjusted relative risks (aRRs) and 95% confidence intervals (CIs).

RESULTS

 Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased from 1.6 to 2.2%. After multivariable adjustment, an increased risk for the composite maternal adverse outcome was found in Black (aRR = 1.10, 95% CI = 1.09-1.11), Hispanic (aRR = 1.04, 95% CI = 1.02-1.05), and Asian/Pacific Islander (aRR = 1.07, 95% CI = 1.05-1.10), compared with White individuals. Compared with White individuals, the risk of the composite neonatal adverse outcome was higher in Black (aRR = 1.39, 95% CI = 1.37-1.41), Hispanic (aRR = 1.15, 95% CI = 1.13-1.16), Asian/Pacific Islander (aRR = 1.34, 95% CI = 1.31-1.37), and American Indian (aRR = 1.12, 95% CI = 1.07-1.17). The racial and ethnic disparity remained unchanged during the study period.

CONCLUSION

 We found a racial and ethnic disparity with maternal and neonatal adverse outcomes in pregnancies with chronic hypertension that remained unchanged throughout the study period.

KEY POINTS

· Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased.. · Among people with chronic hypertension, there are racial and ethnic disparities in adverse outcomes.. · Black, Hispanic, and Asian/Pacific Islander have a higher risk of the adverse neonatal outcomes..

Activation of the Renin-Angiotensin-Aldosterone System Is Attenuated in Hypertensive Compared with Normotensive Pregnancy

Hypertension during pregnancy increases the risk of adverse maternal and fetal outcomes, but the mechanisms of pregnancy hypertension are not precisely understood. Elevated plasma renin activity and aldosterone concentrations play an important role in the normal physiologic adaptation to pregnancy. These effectors are reduced in patients with pregnancy hypertension, creating an opportunity to define the features of the renin-angiotensin-aldosterone system (RAAS) that are characteristic of this disorder. In the current study, we used a novel LC-MS/MS-based methodology to develop comprehensive profiles of RAAS peptides and effectors over gestation in a cohort of 74 pregnant women followed prospectively for the development of gestational hypertension and pre-eclampsia (HYP, 27 patients) versus those remaining normotensive (NT, 47 patients). In NT pregnancy, the plasma renin activity surrogate, (PRA-S, calculated from the sum of Angiotensin I + Angiotensin II) and aldosterone concentrations significantly increased from the first to the third trimester, accompanied by a modest increase in the concentrations of angiotensin peptide metabolites. In contrast, in HYP pregnancies, PRA-S and angiotensin peptides were largely unchanged over gestation, and third-trimester aldosterone concentrations were significantly lower compared with those in NT pregnancies. The results indicated that the predominant features of pregnancies that develop HYP are stalled or waning activation of the RAAS in the second half of pregnancy (accompanied by unchanging levels of angiotensin peptides) and the attenuated secretion of aldosterone.

Glomerular diseases in pregnancy: pragmatic recommendations for clinical management

Our understanding of the various aspects of pregnancy in women with kidney diseases has significantly improved in the last decades. Nevertheless, little is known about specific kidney diseases. Glomerular diseases are not only a frequent cause of chronic kidney disease in young women, but combine many challenges in pregnancy: immunologic diseases, hypertension, proteinuria, and kidney tissue damage. An international working group undertook the review of available current literature and elicited expert opinions on glomerular diseases in pregnancy with the aim to provide pragmatic information for nephrologists according to the present state-of-the-art knowledge. This work also highlights areas of clinical uncertainty and emphasizes the need for further collaborative studies to improve maternal and fetal health.

Mineralocorticoid Receptor Activation in Vascular Insulin Resistance and Dysfunction

Systemic insulin resistance is characterized by reduced insulin metabolic signaling and glucose intolerance. Mineralocorticoid receptors (MRs), the principal receptors for the hormone aldosterone, play an important role in regulating renal sodium handling and blood pressure. Recent studies suggest that MRs also exist in tissues outside the kidney, including vascular endothelial cells, smooth muscle cells, fibroblasts, perivascular adipose tissue, and immune cells. Risk factors, including excessive salt intake/salt sensitivity, hypertension, and obesity, can lead to the activation of vascular MRs to promote inflammation, oxidative stress, remodeling, and fibrosis, as well as cardiovascular stiffening and microcirculatory impairment. These pathophysiological changes are associated with a diminished ability of insulin to initiate appropriate intracellular signaling events, resulting in a reduced glucose uptake within the microcirculation and related vascular insulin resistance. Therefore, the pharmacological inhibition of MR activation provides a potential therapeutic option for improving vascular function, glucose uptake, and vascular insulin sensitivity. This review highlights recent experimental and clinical data that support the contribution of abnormal MR activation to the development of vascular insulin resistance and dysfunction.

Racial and Ethnic Disparities in Maternal and Neonatal Outcomes among Women with Chronic Hypertension

OBJECTIVE

The objective of this study was to compare maternal and neonatal outcomes in women with chronic hypertension by maternal race and ethnicity.

METHODS

A retrospective cohort study of women with chronic hypertension was performed from the Consortium on Safe Labor (2002-2008). Maternal self-reported race and ethnicity were analyzed as non-Hispanic White, non-Hispanic Black, and Hispanic. Maternal outcomes included cesarean birth, postpartum hemorrhage, blood transfusion, placental abruption, eclampsia, maternal intensive care unit admission, and death. Neonatal outcomes included preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA), 5-minute Apgar <7, respiratory distress syndrome, hypoxic-ischemic encephalopathy, intraventricular hemorrhage, neonatal intensive care unit admission, sepsis, and death. Univariable and multivariable analyses were performed to examine the association between maternal race and ethnicity and perinatal outcomes.

RESULTS

A total of 2,729 women were included. In unadjusted analysis, non-Hispanic White women had higher rates of placental abruption and Hispanic women had higher rates of placental abruption and eclampsia. In multivariable analysis, non-Hispanic Black continued to have higher odds of placental abruption (adjusted odds ratio 4.16, 95% confidence interval 1.29-18.70), but the rest of the maternal outcomes did not differ between the groups. When comparing neonatal outcomes, PTB, SGA, and LBW were more frequent in, 5-minute Apgar <7 non-Hispanic Black and Hispanic women compared with non-Hispanic White women. In addition, 5-minute Apgar <7 and neonatal sepsis were more frequent in non-Hispanic Black neonates and neonatal death was more frequent in Hispanic neonates compared with non-Hispanic White women. In multivariable regression, neonates of non-Hispanic Black women had higher odds of PTB, SGA, LBW, 5-minute Apgar < 7, and sepsis compared with non-Hispanic White women. Similarly, neonates of Hispanic women had higher odds of SGA, LBW, and death.

CONCLUSION

Significant racial and ethnic disparities were identified mainly in neonatal outcomes of women with chronic hypertension.

KEY POINTS

· Non-Hispanic Black women with chronic hypertension had higher rates of placental abruption.. · Neonates of non-Hispanic Black women with chronic hypertension had higher odds of PTB, SGA, and LBW.. · Neonates of Hispanic women with chronic hypertension had higher odds of SGA, LBW, and neonatal death..

A Systematic Review of Maternal Serum Syndecan-1 and Preeclampsia

Exploration of novel biomarkers has been gaining popularity in preeclampsia, which is currently being diagnosed based on clinical criteria alone. Soluble syndecan-1, released from one of the proteoglycans associated with the syncytiotrophoblastic layer of the placenta, is affected in patients with abnormal placentation. This article is the first systematic literature review that evaluates the relationship between the antepartum serum levels of the syndecan-1 and preeclampsia. Eight studies were selected after screening and quality appraisal, and data were analyzed. The serum concentration of syndecan-1 was found to correlate positively with the gestational age in all pregnancies and negatively with the systolic blood pressure in patients with preeclampsia. Extremely low levels of soluble syndecan-1 may be helpful as a predictor for the development of preeclampsia during gestation.

A Critical Review on the Use of Race in Understanding Racial Disparities in Preeclampsia

BACKGROUND

Preeclampsia is a significant cause of maternal morbidity and mortality, affecting up to 8% of pregnancies globally. Although the precise etiology is still under study, the literature suggests that vascular changes reduce placental perfusion and affect the remodeling of spiral arteries to create the hallmark feature of preeclampsia: elevated blood pressure. Screening for preeclampsia is currently recommended for all pregnant women, particularly if risk factors exist. A noted risk factor codified in guidelines is "African-American race."

CONTENT

We summarize the racial disparities in preeclampsia incidence, morbidity, and mortality. We consider the limitations of using race to understand disparities by also examining multiethnic, immigration, and international studies. We then critically evaluate laboratory analytes associated with racial disparities of preeclampsia and explore other mechanisms of action, such as socioeconomic status, stress, and access to care.

SUMMARY

Black and African-American women are consistently at higher risk of preeclampsia incidence, morbidity, and mortality than their white counterparts. Asian women are consistently at lower risk of preeclampsia, whereas the association for Hispanic women remains unclear. When these broad racial categories are subdivided by geographic or cultural origin, preeclampsia disparities within racial groups are identified. The limited literature suggests that sub-Saharan African immigrants tend to have a higher risk of preeclampsia than US-born white populations but a lower risk than US-born Black women. Existing studies seeking to identify racial differences in analytes have limited research designs and tend to operationalize race as a proxy for biologically inherent (i.e., genetic) differences between races despite a plethora of other possible explanatory mechanisms.

CLDN3 expression and function in pregnancy-induced hypertension

This aim of the present study was to investigate the expression and function of claudin 3 (CLDN3) in pregnancy-induced hypertension. The mRNA expression levels of CLDN3 in the placental tissue and peripheral blood of patients with pregnancy-induced hypertension were measured using reverse transcription-quantitative PCR. Human trophoblast HTR8/SVneo cells overexpressing CLDN3 were generated using a lentiviral vector. Cell Counting kit-8 (CCK-8) assay, flow cytometry, Transwell chamber assays, confocal laser scanning microscopy and western blot analysis were performed to detect cell proliferation, invasion, migration and apoptosis, in addition to matrix metalloproteinase (MMP) expression and ERK1/2 phosphorylation. The mRNA expression levels of CLDN3 were significantly reduced in the placental tissues and peripheral blood samples of patients with pregnancy-induced hypertension compared with healthy pregnant controls. CLDN3 overexpression significantly increased HTR8/SVneo cell proliferation, invasion and migration whilst reducing apoptosis. HTR8/SVneo cells overexpressing CLDN3 also exhibited increased myofiber levels, increased MMP-2 and MMP-9 expression and increased ERK1/2 signaling activity. CLDN3 downregulation may be associated with the pathogenesis of pregnancy-induced hypertension. In conclusion, CLDN3 promotes the proliferative and invasive capabilities of human trophoblast cells, with the underlying mechanisms possibly involving upregulation of MMP expression via the ERK1/2 signaling pathway.

Maternal Sildenafil vs Placebo in Pregnant Women With Severe Early-Onset Fetal Growth Restriction: A Randomized Clinical Trial

IMPORTANCE

Severe early onset fetal growth restriction caused by placental dysfunction leads to high rates of perinatal mortality and neonatal morbidity. The phosphodiesterase 5 inhibitor, sildenafil, inhibits cyclic guanosine monophosphate hydrolysis, thereby activating the effects of nitric oxide, and might improve uteroplacental function and subsequent perinatal outcomes.

OBJECTIVE

To determine whether sildenafil reduces perinatal mortality or major morbidity.

DESIGN, SETTING, AND PARTICIPANTS

This placebo-controlled randomized clinical trial was conducted at 10 tertiary referral centers and 1 general hospital in the Netherlands from January 20, 2015, to July 16, 2018. Participants included pregnant women between 20 and 30 weeks of gestation with severe fetal growth restriction, defined as fetal abdominal circumference below the third percentile or estimated fetal weight below the fifth percentile combined with Dopplers measurements outside reference ranges or a maternal hypertensive disorder. The trial was stopped early owing to safety concerns on July 19, 2018, whereas benefit on the primary outcome was unlikely. Data were analyzed from January 20, 2015, to January 18, 2019. The prespecified primary analysis was an intention-to-treat analysis including all randomized participants.

INTERVENTIONS

Participants were randomized to sildenafil, 25 mg, 3 times a day vs placebo.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of perinatal mortality or major neonatal morbidity until hospital discharge.

RESULTS

Out of 360 planned participants, a total of 216 pregnant women were included, with 108 women randomized to sildenafil (median gestational age at randomization, 24 weeks 5 days [interquartile range, 23 weeks 3 days to 25 weeks 5 days]; mean [SD] estimated fetal weight, 458 [160] g) and 108 women randomized to placebo (median gestational age, 25 weeks 0 days [interquartile range, 22 weeks 5 days to 26 weeks 3 days]; mean [SD] estimated fetal weight, 464 [186] g). In July 2018, the trial was halted owing to concerns that sildenafil may cause neonatal pulmonary hypertension, whereas benefit on the primary outcome was unlikely. The primary outcome, perinatal mortality or major neonatal morbidity, occurred in the offspring of 65 participants (60.2%) allocated to sildenafil vs 58 participants (54.2%) allocated to placebo (relative risk, 1.11; 95% CI, 0.88-1.40; P = .38). Pulmonary hypertension, a predefined outcome important for monitoring safety, occurred in 16 neonates (18.8%) in the sildenafil group vs 4 neonates (5.1%) in the placebo group (relative risk, 3.67; 95% CI, 1.28-10.51; P = .008).

CONCLUSIONS AND RELEVANCE

These findings suggest that antenatal maternal sildenafil administration for severe early onset fetal growth restriction did not reduce the risk of perinatal mortality or major neonatal morbidity. The results suggest that sildenafil may increase the risk of neonatal pulmonary hypertension.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02277132.

A systematic review and meta-analysis indicates long-term risk of chronic and end-stage kidney disease after preeclampsia

Preeclampsia is a pregnancy-related syndrome of variable severity, classically characterized by acute kidney involvement, with hypertension and/or proteinuria and reduced kidney function. Once considered a self-limited disease healed by delivery, it is now acknowledged that preeclampsia can affect cardiovascular and kidney health in the long term. The entity of risk has not been established and consequently follow-up policies have not been defined. Here we undertook a systematic review to gain better insights into the need for post-preeclampsia follow-up. Articles published between January 2000 and March 2018 were selected, dealing with at least 20 preeclampsia patients, with follow-up of 4 years or more (MEDLINE, Embase, and Cochrane Library). No quality selection or language restriction was performed. Of the 10,510 titles and abstracts originally considered, 21 papers were selected, providing information on 110,803 cases with and 2,680,929 controls without preeclampsia, with partial overlap between studies on the same databases. Heterogeneity was high, and a random meta-analytic model selected. The increase in risk of end stage renal disease after preeclampsia was significant (meta-analytic risk ratios (95% confidence interval) 6.35 (2.73-14.79)); the risk of albuminuria and chronic kidney disease increased but statistical significance was not reached (4.31 (0.95-19.58) and 2.03 (0.58-7.32), respectively). Translating meta-analytic risk into the number of patients who need follow-up to detect one adverse event, 310 patients with preeclampsia are needed to identify one woman with end stage renal disease or four to identify one woman with albuminuria. Heterogeneity in definitions, insufficient follow-up and incomplete recruitment may account for discrepancies. Thus, preeclampsia significantly increases the risk of end stage renal disease. However, there is lack of sufficient data to show a relationship between preeclampsia, albuminuria and chronic kidney disease, underlining the need for further prospective studies.

Using proteomics to advance the search for potential biomarkers for preeclampsia: A systematic review and meta-analysis

BACKGROUND

Preeclampsia (PE) is a leading cause of maternal and perinatal morbidity and mortality worldwide. Although predictive multiparametric screening is being developed, it is not applicable to nulliparous women, and is not applied to low-risk women. As PE is considered a heterogenous disorder, it is unlikely that any single multiparametric screening protocol containing a small group of biomarkers could have the required accuracy to predict all PE subgroups. Given the etiology of PE is complex and not fully understood, it begs the question, whether the search for biomarkers based on the predominant view of impaired placentation involving factors predominately implicated in angiogenesis and inflammation, has been too limiting. Here we highlight the enormous potential of state-of-the-art, high-throughput proteomics, to provide a comprehensive and unbiased approach to biomarker identification.

METHODS AND FINDINGS

Our literature search identified 1336 articles; after review, 45 studies with proteomic data from PE women that were eligible for inclusion. From 710 proteins with altered abundance, we identified 13 common circulating proteins, some of which had not been previously considered as prospective biomarkers of PE. An additional search of the literature for original publications testing any of the 13 common proteins using non-proteomic techniques was also undertaken. Strikingly, 9 of these common proteins had been independently evaluated in PE studies as potential biomarkers.

CONCLUSION

This study highlights the potential of using high-throughput data sets, which are comprehensive and without bias, to identify a profile of proteins that may improve predictions of PE and understanding of its etiology. We bring to the attention of the medical and research communities that the strengths and advantages of using data from high-throughput studies for biomarker discovery would be increased dramatically, if first and second trimester samples were collected for proteomics, and if standardized guidelines for patient reporting and data collection were implemented.

Diagnostic Indicators of Superimposed Preeclampsia in Women With CKD

Introduction

Diagnosis of superimposed preeclampsia in women with chronic kidney disease (CKD) is complicated by the presence of hypertension and proteinuria due to renal disease. The aims of this study were to determine mechanistic links between superimposed preeclampsia and renin-angiotensin system activation, endothelial pathology, complement dysfunction, and tubular injury, and to explore the role of diagnostic indicators of superimposed preeclampsia.

Methods

Plasma and urinary biomarkers derived from the renin-angiotensin system (active renin, angiotensinogen), endothelial glycocalyx (hyaluronan, intercellular adhesion molecule, vascular cell adhesion molecule [VCAM], P-selectin, E-selectin), complement activation (C3a, C5a, complement factor H, C5b-9), and tubular injury (kidney injury molecule-1, urinary lipocalin-2) were quantified in 60 pregnant women with CKD including 15 women at the time of superimposed preeclampsia diagnosis and 45 women who did not develop superimposed preeclampsia, 18 women with preeclampsia, and 20 normal pregnancies. Correlation with placental growth factor was assessed.

Results

Plasma concentrations of hyaluronan (67.5 ng/ml vs. 27.5 ng/ml, P = 0.0017, receiver operating characteristic area 0.80) and VCAM (1132 ng/ml vs. 659 ng/ml, P < 0.0001, receiver operating characteristic area 0.86) distinguished women with CKD and superimposed preeclampsia from those without superimposed preeclampsia, and correlated with placental growth factor concentration. The diagnostic discrimination of markers of the renin-angiotensin system was reduced by adjustment for chronic hypertension, antihypertensive drug use, and black ethnicity. Other markers offered limited or no diagnostic discrimination for superimposed preeclampsia.

Conclusion

This study suggests that endothelial dysfunction contributes to the pathophysiology of superimposed preeclampsia and a diagnostic role for plasma hyaluronan and VCAM is hypothesized.

Acute IgA-Dominant Glomerulonephritis Associated with Syphilis Infection in a Pregnant Teenager: A New Disease Association

Chronic kidney disease (CKD) is increasingly recognized as a risk factor in pregnancy; the differential diagnosis between CKD and preeclampsia (PE) may be of pivotal importance for pregnancy management and for early treatment of CKD. Acknowledging this connection may be useful also in a wider context, such as in the case reported in this paper, which for the first time describes an association between syphilis infection and IgA-dominant glomerulonephritis. A 16-year-old woman, referred to a general hospital due to a seizure, was found to be unknowingly pregnant. Based on hypertension and nephrotic proteinuria, she was initially diagnosed with PE. Immunological tests, as well as hepatitis and HIV tests showed negative results. However, secondary syphilis was diagnosed. In discordance with the PE diagnosis, urinalysis showed glomerular microhematuria with cellular casts. Proteinuria and hypertension did not remit after delivery, which was made via caesarean section, due to uncontrolled hypertension, at an estimated gestational age of 29 weeks. A male baby, weighing 1.1 kg (6.5 centile) was born. The baby was hospitalized in the neonatal intensive care unit, where he developed subependymal hemorrhage and thrombocytopenia, and neonatal syphilis was diagnosed. The mother underwent a kidney biopsy one week after delivery, leading to the diagnosis of IgA-dominant postinfectious glomerulonephritis. Mother and child were treated with support and antibiotic therapy, and were discharged in good clinical conditions four weeks later. Four months after delivery, the mother was normotensive without therapy, with normal kidney function and without hematuria or proteinuria. In conclusion, this case suggests that IgA-dominant postinfectious glomerulonephritis should be added to the spectrum of syphilis-associated glomerulonephritides, and underlines the need for a careful differential diagnosis with CKD in all cases of presumed PE. While diagnosis relies on kidney biopsy, urinary sediment, a simple and inexpensive test, can be the first step in distinguishing PE from other nephropathies.