Chapter 28 Hypertensive disorders of pregnancy and eclampsia

Risk of future cardiovascular diseases in different years postpartum after hypertensive disorders of pregnancy: A systematic review and meta-analysis

OBJECTIVE

There are limited data on the optimal timing and frequency of postpartum follow-up visits after hypertensive disorders of pregnancy (HDP) for primary prevention and early detection of cardiovascular diseases (CVDs) in high-risk women. We aimed to evaluate the risk of cardiovascular outcomes later in life in women with prior HDP in different years postpartum and in preeclamptic women with severe features, or early onset of preeclampsia.

METHODS

We searched MEDLINE, Cochrane Library, Web of Science, and Scopus without language restriction for relevant articles published from inception to March 16, 2022. We included prospective and retrospective cohort studies assessing hypertension, ischemic heart disease, heart failure, venous thromboembolism, peripheral vascular disease, stroke, dementia, composite cardiovascular and/or cerebrovascular diseases, and mortality after 6 weeks postpartum, in women with prior HDP compared with controls. Two authors independently selected and appraised the studies. Article quality was independently assessed using the Newcastle-Ottawa Scale (NOS). Random-effect models were used for meta-analysis. Stratified analyses based on years postpartum, severity, and onset of preeclampsia were performed.

RESULTS

We included 59 studies for qualitative review, of which 56 were included in quantitative meta-analysis, involving 1,262,726 women with prior HDP and 14,711,054 controls. Women with prior HDP had increased risks of hypertension (relative risk [RR] 3.46, 95% confidence interval [CI]: 2.67-4.49), ischemic heart disease (RR 2.06, 95% CI: 1.38-3.08), and heart failure (RR 2.53, 95% CI: 1.28-5.00) later in life, compared with those with normotensive pregnancies. The risk of hypertension was highest during 5 years postpartum (RR 5.34, 95% CI: 2.74-10.39). Compared with normotensive pregnancies, the risk of future CVDs significantly increased in preeclamptic women.

DISCUSSION

A history of HDP is associated with approximately 2- to 4-fold increase in the risk of CVDs. Screening for CVDs and their risk factors in women with prior HDP since delivery, especially the first 5 years after delivery is suggested for early detection and appropriate management. Evidence on the risks of CVDs in preeclampsia with severe features and early onset of preeclampsia is limited due to having few studies and high heterogeneity.

FUNDING

The Royal Golden Jubilee PhD Program-RGJ (PHD/0183/2561); Thailand Science Research and Innovation (TSRI) Research Career Development Grant-RSA (RSA6180009); Targeted Research Grants Program of the Faculty of Medicine, Prince of Songkla University, Thailand.

REGISTRATION

CRD42020191550.

Guidelines-similarities and dissimilarities: a systematic review of international clinical practice guidelines for pregnancy hypertension

OBJECTIVE

This study aimed to review pregnancy hypertension clinical practice guidelines to inform international clinical practice and research priorities.

STUDY ELIGIBILITY CRITERIA

Relevant national and international clinical practice guidelines, 2009-19, published in English, French, Dutch or German.

STUDY APPRAISAL AND SYNTHESIS METHODS

Following published methods and prospective registration (CRD42019123787), a literature search was updated. CPGs were identified by 2 authors independently who scored quality and usefulness for practice (Appraisal of Guidelines for Research and Evaluation II instrument), abstracted data, and resolved any disagreement by consensus.

RESULTS

Of note, 15 of 17 identified clinical practice guidelines (4 international) were deemed "clinically useful" and had recommendations abstracted. The highest Appraisal of Guidelines for Research and Evaluation II scores were from government organizations, and scores have improved over time. The following were consistently recommended: (1) automated blood pressure measurement with devices validated for pregnancy and preeclampsia, reflecting increasing recognition of the prevalence of white-coat hypertension and the potential usefulness of home blood pressure monitoring; (2) use of dipstick proteinuria testing for screening followed by quantitative testing by urinary protein-to-creatinine ratio or 24-hour urine collection; (3) key definitions and most aspects of classification, including a broad definition of preeclampsia (which includes proteinuria and maternal end-organ dysfunction, including headache and visual symptoms and laboratory abnormalities of platelets, creatinine, or liver enzymes) and a recognition that it can worsen after delivery; (4) preeclampsia prevention with aspirin; (5) treatment of severe hypertension, most commonly with intravenous labetalol, oral nifedipine, or intravenous hydralazine; (6) treatment for nonsevere hypertension when undertaken, with oral labetalol (in particular), methyldopa, or nifedipine, with recommendations against the use of renin-angiotensin-aldosterone inhibitors; (7) magnesium sulfate for eclampsia treatment and prevention among women with "severe" preeclampsia; (8) antenatal corticosteroids for preterm birth but not hemolysis, elevated liver enzymes, and low platelet count syndrome; (9) delivery at term for preeclampsia; (10) a focus on usual labor and delivery care but avoidance of ergometrine; and (11) an appreciation that long-term health complications are increased in incidence, mandating lifestyle change and risk factor modification. Lack of uniformity was seen in the following areas: (1) the components of a broad preeclampsia definition (specifically respiratory and gastrointestinal symptoms, fetal manifestations, and biomarkers), what constitutes severe preeclampsia, and whether the definition has utility because at present what constitutes severe preeclampsia by some guidelines that mandate proteinuria now defines any preeclampsia for most other clinical practice guidelines; (2) how preeclampsia risk should be identified early in pregnancy, and aspirin administered for preeclampsia prevention, because multivariable models (with biomarkers and ultrasonography added to clinical risk markers) used in this way to guide aspirin therapy can substantially reduce the incidence of preterm preeclampsia; (3) the value of calcium added to aspirin for preeclampsia prevention, particularly for women with low intake and at increased risk of preeclampsia; (4) emerging recommendations to normalize blood pressure with antihypertensive agents even in the absence of comorbidities; (5) fetal neuroprotection as an indication for magnesium sulfate in the absence of "severe" preeclampsia; and (6) timing of birth for chronic and gestational hypertension and preterm preeclampsia.

CONCLUSION

Consistent recommendations should be implemented and audited. Inconsistencies should be the focus of research.

Cholesterol Crystals and NLRP3 Mediated Inflammation in the Uterine Wall Decidua in Normal and Preeclamptic Pregnancies

Preeclampsia is a hypertensive and inflammatory pregnancy disorder associated with cholesterol accumulation and inflammation at the maternal-fetal interface. Preeclampsia can be complicated with fetal growth restriction (FGR) and shares risk factors and pathophysiological mechanisms with cardiovascular disease. Cholesterol crystal mediated NLRP3 inflammasome activation is central to cardiovascular disease and the pathway has been implicated in placental inflammation in preeclampsia. Direct maternal-fetal interaction occurs both in the uterine wall decidua and at the placental surface and these aligned sites constitute the maternal-fetal interface. This study aimed to investigate cholesterol crystal accumulation and NLRP3 inflammasome expression by maternal and fetal cells in the uterine wall decidua of normal and preeclamptic pregnancies. Pregnant women with normal (n = 43) and preeclamptic pregnancies with (n = 28) and without (n = 19) FGR were included at delivery. Cholesterol crystals were imaged in decidual tissue by both second harmonic generation microscopy and polarization filter reflected light microscopy. Quantitative expression analysis of NLRP3, IL-1β and cell markers was performed by immunohistochemistry and automated image processing. Functional NLRP3 activation was assessed in cultured decidual explants. Cholesterol crystals were identified in decidual tissue, both in the tissue stroma and near uterine vessels. The cholesterol crystals in decidua varied between pregnancies in distribution and cluster size. Decidual expression of the inflammasome components NLRP3 and IL-1β was located to fetal trophoblasts and maternal leukocytes and was strongest in areas of proximity between these cell types. Pathway functionality was confirmed by cholesterol crystal activation of IL-1β in cultured decidual explants. Preeclampsia without FGR was associated with increased trophoblast dependent NLRP3 and IL-1β expression, particularly in the decidual areas of trophoblast and leukocyte proximity. Our findings suggest that decidual accumulation of cholesterol crystals may activate the NLRP3 inflammasome and contribute to decidual inflammation and that this pathway is strengthened in areas with close maternal-fetal interaction in preeclampsia without FGR.

Postpartum lifestyle interventions among women with pre-eclampsia: a scoping review protocol

INTRODUCTION

Compared to women with normotensive pregnancies, women with a history of pre-eclampsia have a roughly fourfold increased risk of developing chronic arterial hypertension and a twofold increased risk of developing cardiovascular disease (CVD). Lifestyle changes, such as increased physical activity, weight loss, smoking cessation and healthy diet, are effective for CVD prevention in the general population. However, no scoping review or systematic review of postpartum lifestyle interventions among women with pre-eclampsia have, to our best knowledge, been performed. The objective of this scoping review is to provide an overview of the available research literature on postpartum lifestyle interventions to reduce the risk of CVD among women with pre-eclampsia.

METHODS AND ANALYSIS

The protocol is based on the framework outlined by Arksey and O'Malley. Databases to be searched include: PubMed, Embase CINAHL and the JBI Database of Systematic Reviews and Implementation Reports. The search will be performed after the publication of this protocol (estimated to be 1 June 2020) and will be repeated 1 month prior to the submission for publication of the final review (estimated to be 1 January 2021). The review will consider studies that include women in the postpartum period (in particular, but not restricted to, the first 12 months after delivery), with a history of pre-eclampsia. Data will be extracted by two independent reviewers using a data extraction tool including specific details about the population, concept, context, study methods and key findings relevant to the review objective. Any disagreements between the reviewers will be resolved through discussion, or with a third reviewer. The extracted data will be presented in diagrammatic or tabular form that align with the objective of this scoping review. A narrative summary will accompany the tabulated and/or charted results and will describe how the results relate to the reviews objective and questions.

ETHICS AND DISSEMINATION

Since all data will be obtained from publicly available materials, the proposed scoping review does not require ethical approval. The results will be submitted for publication in an open-access peer-reviewed journal and presented at relevant conferences.

Hypertensive Disorders of Pregnancy and Genital Anomalies in Boys: A Danish Nationwide Cohort Study

BACKGROUND

Although congenital abnormalities in the male reproductive tract are common, their causes remain poorly understood. We studied associations between hypertensive disorders of pregnancy (pregestational hypertension, gestational hypertension, and preeclampsia) and the genital anomalies, cryptorchidism (undescended testes), and hypospadias (ventrally displaced urethral meatus).

METHODS

We established a population of 1,073,026 Danish boys born alive between 1 January 1978 and 31 December 2012. By means of Cox regression analyses, we estimated hazard ratios with 95% confidence intervals for cryptorchidism and hypospadias according to type and severity of hypertensive disorder. Further, we used restricted cubic spline analyses to investigate the association between gestational age at onset of severe and moderate preeclampsia and the two genital anomalies.

RESULTS

We found associations between pregestational hypertension and cryptorchidism (HR: 1.3; 95% CI = 1.1, 1.6) and hypospadias (HR: 1.7; 95% CI = 1.3, 2.3), whereas gestational hypertension was only associated with cryptorchidism (HR: 1.2; 95% CI = 1.1, 1.4). Boys of mothers with preeclampsia had the highest occurrence of cryptorchidism and hypospadias, increasing with preeclampsia severity. Women with HELLP syndrome faced the highest risk of having a child with both cryptorchidism (HR: 2.1; 95% CI = 1.4, 3.2) and hypospadias (HR: 3.9; 95% CI = 2.5, 6.1). Further, the occurrence increased with early onset of preeclampsia diagnosis.

CONCLUSIONS

These findings support the hypotheses that preeclampsia and genital anomalies share common etiologic factors and that placental dysfunction and androgen deficiency in early pregnancy are important in the etiology of male genital anomalies.

Early gestational age at preeclampsia onset is associated with subclinical atherosclerosis 12 years after delivery

INTRODUCTION

Women with a history of preeclampsia have increased risk of cardiovascular disease later in life. However, it is unclear whether early gestational age at preeclampsia onset is associated with higher cardiovascular disease risk. This study aimed to test the association between gestational age at preeclampsia onset (including the early-onset/late-onset preeclampsia distinction) and subclinical atherosclerosis and arterial stiffness in age-matched women 12 years after index pregnancy.

MATERIAL AND METHODS

Eligible participants were identified in two Danish registries. Main outcome measures were carotid plaque presence, carotid intima-media thickness, aortic pulse wave velocity, and augmentation index adjusted for heart rate.

RESULTS

Twenty-four women with previous early-onset preeclampsia, 24 with previous late-onset preeclampsia and 24 with previous normotensive pregnancies were included after matching on age (±2 years) and time since delivery (±1 year). In all outcome measures, the early-onset group had the highest percentage or mean value. In the adjusted analysis, the early-onset group significantly differed from the late-onset group in all outcome measures except aortic pulse wave velocity. The early-onset group also had significantly higher carotid intima-media thickness (average and left) compared with the normotensive group. Gestational age at preeclampsia onset as a continuous variable was significantly associated to both carotid plaque presence and carotid intima-media thickness (average and right).

CONCLUSIONS

Gestational age at preeclampsia onset is negatively associated with markers of subclinical atherosclerosis 12 years after delivery. Potentially, gestational age at preeclampsia onset might be helpful in directing cardiovascular disease prevention after preeclampsia.