Epidemiology of hypertensive disorders in pregnancy: prevalence, risk factors, predictors and prognosis

Novel biomarker profiles in experimental aged maternal mice with hypertensive disorders of pregnancy

Recently, advanced maternal age (AMA) has increased in Western countries because of late marriage and advances in assisted reproductive technology. One major complication of AMA is hypertensive disorders of pregnancy (HDP). While clinical investigations into human AMA have been reported, there has been limited information obtained from basic research. In this investigation, we established the AMA mouse model using aged pregnant ICR mice. We demonstrated that the phenotypes of aged pregnant ICR mice reflect the same characteristics as human AMA. The significant findings of our investigation are as follows: (1) The AMA mouse model manifested the same complication phenotypes of human AMA, including maternal obesity, declining fertility, small for gestational age, and a higher rate of intrauterine fetal death; (2) The AMA mouse model exhibited an increasing systolic blood pressure at late gestation (108.2 ± 7.7 vs. 92.7 ± 5.7 mmHg, P < 0.01) that normalized after delivery similar to human HDP patients; and (3) While HDP and placental dysfunction are complicated, AMA mice and human HDP AMA patients manifested a low serum soluble fms-like tyrosine kinase-1 (sFlt-1) level in late gestation (AMA group vs. control group, mice, 16800.0 ± 10709.5 vs. 26611.9 ± 8702.0 pg/mL, respectively, P < 0.01; human, 8507.6 ± 3298.7 vs. 14816.9 ± 5413.5 pg/mL, respectively, P < 0.05). In conclusion, the aged pregnant mouse model resembled human AMA. The AMA mouse model was complicated with HDP despite the low serum sFlt-1 level. Our findings provide evidence that the serum sFlt-1 level does not necessarily reflect the conventional pathogenesis of HDP in aged human and murine pregnancies and may contribute to the future management of HDP in AMA.

Prevalence, Risk Factors, and Fetal and Maternal Outcomes of Hypertensive Disorders of Pregnancy: A Retrospective Study in Western Saudi Arabia

Objectives

We sought to estimate the prevalence of hypertensive disorders of pregnancy (HDP) in Saudi Arabia as well as the risk factors of HDP, and maternal and fetal outcomes.

Methods

We retrospectively evaluated the medical records of 9493 women who delivered at King Abdulaziz University Hospital, a tertiary care center, between January 2015 and June 2017. All cases of HDP were included.

Results

We identified 224 pregnant women with HDP in our patient cohort, giving a prevalence of 2.4%. Their mean age was 31.3±6.7 years, with an average gravidity of 4.0 and average parity of 3.0. The most prevalent subtype of HDP was preeclampsia (54.9%) while 29.5% of the women had gestational hypertension, and 8.0% had eclampsia. The prevalence of subtypes of HDP differed significantly with gravidity, and mean age differed significantly with HDP subtype. Personal and family histories of preeclampsia and the presence of diabetes were more prevalent in women with preeclampsia and gestational hypertension; however, only the difference in diabetes prevalence was significant. The overall prevalence of maternal complications was 9.4% and the prevalence of maternal mortality was 1.3%. Multigravid women and women with chronic hypertension were at increased risk of prematurity compared to other pregnant women, but not significantly.

Conclusions

The prevalence of HDP was relatively low in our cohort. However, to prevent harmful impacts on both the mother and fetus, screening for this disorder is recommended early in pregnancy.

Exposure to air pollution during preconceptional and prenatal periods and risk of hypertensive disorders of pregnancy: a retrospective cohort study in Seoul, Korea

Background

Previous studies suggested associations between prenatal exposure to air pollution and hypertensive disorders of pregnancy. We explored the associations between ambient concentrations of five major air pollutants during preconceptional and prenatal periods and three hypertensive disorders of pregnancy in Seoul, Korea, using a population-representative cohort.

Methods

We obtained heath and demographic data of pregnant women residing in Seoul for 2002–2013 from the Korean National Health Insurance Service–National Sample Cohort. For mother’s individual exposures to air pollution, we computed concentrations of particulate matter ≤10 μm in diameter (PM₁₀), nitrogen dioxide (NO₂), carbon monoxide (CO), sulfur dioxide (SO₂), and ozone (O₃) during 1, 3, 6, and 12 months to birth using regulatory monitoring data in Seoul. The associations between air pollution and hypertensive disorders were explored by using logistic regression models after adjusting for individual confounders.

Results

Among 18,835 pregnant women in Seoul, 0.6, 0.5, and 0.4% of women developed gestational hypertension, preeclampsia, and preeclampsia requiring magnesium sulfate (Mg-preeclampsia), respectively. Although most odds ratios (ORs) were not statistically significant, we found increasing risk gradients with disease severity depending on the pollutant. There was the association between PM₁₀ during 6 months to birth and gestational hypertension (OR for an interquartile range increase = 1.68 [95% confidence interval = 1.09–2.58]). NO₂ and ozone during 12 and 1 month, respectively, before birth were associated with Mg-preeclampsia (1.43 [1.01–2.03], 1.53 [1.03–2.27]).

Conclusions

We observed positive associations of exposure to some air pollutants before and during pregnancy with hypertensive disorders of pregnancy among the Korean general population. Future studies with refined exposure metrics should confirm our findings.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1982-z) contains supplementary material, which is available to authorized users.

Neonatal outcomes of extremely preterm infants exposed to maternal hypertension and cigarette smoking

OBJECTIVE

To study the outcomes of extremely preterm infants of hypertensive mothers who smoke.

STUDY DESIGN

This retrospective cohort study included infants born between 2003 and 2012 at <29 weeks' gestation and admitted to neonatal intensive care units participating in the Canadian Neonatal Network. Infants were divided into four mutually exclusive groups. Infants of hypertensive mothers who smoked; infants of hypertensive, non-smoking mothers; infants of normotensive mothers who smoked; and infants of normotensive, non-smoking mothers. Using infants of normotensive, non-smoking mothers as the reference group, neonatal outcomes were compared between the groups. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were calculated using univariate and multivariate regression analysis.

RESULTS

Of the 12,307 eligible infants, 172 had hypertensive mothers who smoked, 1689 had hypertensive non-smoking mothers, 1535 had normotensive mothers who smoked, and 8911 had normotensive non-smoking mothers. Compared to infants of normotensive non-smoking mothers, infants of hypertensive mothers, regardless of smoking status, had higher odds of developing bronchopulmonary dysplasia (AORs of smokers 1.62; 95% CI 1.12-2.35 and of non-smokers 1.43; 95% CI 1.24-1.64). There was no difference in the odds of mortality and retinopathy of prematurity stage ≥3 between the groups. Infants of hypertensive, non-smoking mothers had decreased odds of intraventricular hemorrhage >grade 2 and higher odds of necrotizing enterocolitis. There was decreased odds of hypertension if the mother was a smoker (AOR 0.71; 95% CI 0.59-0.85).

CONCLUSION

Maternal hypertension is associated with increased rates of bronchopulmonary dysplasia, irrespective of smoking status.

Hemoglobin levels during the first trimester of pregnancy are associated with the risk of gestational diabetes mellitus, pre-eclampsia and preterm birth in Chinese women: a retrospective study

BACKGROUND

Hemoglobin (Hb) measurement is a standard test among pregnant women during the first perinatal visit that is used to evaluate physical status and anemia. However, studies focusing on Hb levels and pregnancy outcomes are scarce. This study aimed to determine whether Hb levels in early pregnancy were associated with the risk of gestational diabetes mellitus (GDM), pre-eclampsia (PE) and preterm birth.

METHODS

A hospital-based retrospective study was conducted among 21,577 singleton, non-smoking pregnancies between June 2013 and January 2015. The demographic data and medical information of each participant were collected individually through questionnaires and patient medical records. Odds ratios were generated using a multivariate logistic regression analysis to evaluate the relative risk of GDM, PE and preterm birth continuously and across different hemoglobin ranges in the overall population and in women from different pre-pregnancy body mass index (BMI) categories, respectively. The level of statistical significance was set at 0.05.

RESULTS

(1) For women who were underweight, normal-weight, overweight and obese, early pregnancy Hb levels were 127.8 ± 10.1 g/L, 129.6 ± 9.7 g/L, 132.2 ± 9.5 g/L and 133.4 ± 9.4 g/L, respectively. (2) Women with GDM and PE had significantly increased Hb levels during early pregnancy compared with controls, whereas women with preterm birth processed significantly decreased Hb levels. (3) After adjusting for confounders, the risks for GDM and PE increased with high maternal Hb (OR: 1.27 for Hb 130-149; OR: 2.06 for Hb ≥ 150 g/L), and the risk for preterm birth decreased with high maternal Hb (OR: 1.30 for Hb 130-149; OR: 2.38 for Hb ≥ 150 g/L) and increased with low maternal Hb (OR: 1.41 for Hb <  110 g/L). Among women whose BMI was < 24 kg/m2, high GDM (OR: 1.27 for Hb 130-149; OR: 1.84 for Hb ≥ 150 g/L) and low preterm rates (OR: 0.77 for Hb 130-149; OR: 0.23 for Hb ≥ 150 g/L) were observed with high Hb, whereas in women whose BMI was ≥24 kg/m2, only high GDM rates were observed with Hb > 150 g/L (OR: 2.33).

CONCLUSION

These findings suggest that Hb levels during early pregnancy play a role in predicting the risk of GDM, PE and preterm birth.

P-wave and QT dispersion in hypertensive disorders of pregnancy

Aim: To compare P-wave and QT dispersion values in hypertensive disorders of pregnancy and controls and also in preeclampsia, chronic hypertension, and gestational hypertension separately.Material and methods: We included 140 hypertensive pregnants and 110 healthy age-matched pregnants in this study. The hypertensive pregnants were divided into three subgroups: preeclampsia (n = 43), chronic hypertension (n = 51), and gestational hypertension (n = 46). P-wave and QT dispersion values were compared between groups.Results: Hypertensive pregnants had higher P-wave (41.74 ± 5.51 vs. 37.73 ± 5.62, p < .001) and QTc dispersion (45.44 ± 7.62 vs. 39.77 ± 8.34, p < .001) values. In subgroup analysis, P-wave dispersion and QTc dispersion were different between preeclamptic, chronic hypertensive, and gestational hypertensive patients. Also, they were significantly higher in chronic hypertension as compared to gestational hypertension and they were higher in preeclampsia than in gestational hypertension. No difference was found according to these parameters between preeclampsia and chronic hypertension. In correlation analysis, both P-wave dispersion and QTc dispersion were positively correlated with systolic (r = 0.409, p < .001 and r = 0.306, p < .001) and diastolic blood pressure (r = 0.390, p < .001 and r = 0.287, p < .001) which are main clinical determinants of hypertensive disorders.Conclusion: In clinical practice, chronic hypertensive pregnants are generally followed up in their future life for cardiovascular disorders. Also, we recommend that we must inform and follow preeclamptic patients for future cardiovascular diseases.

Hypertensive disorders of pregnancy and future heart failure risk: A nationwide population-based retrospective cohort study

OBJECTIVE

To assess whether hypertensive disorders of pregnancy (HDP) increased the risk of subsequent heart failure (HF) and identify possible risk factors.

STUDY DESIGN

A nationwide population-based retrospective cohort study.

MAIN OUTCOME MEASURES

Incidence of heart failure.

RESULTS

Among the 23.3 million individuals registered in the National Health Insurance Research Database in Taiwan, 29,186 patients with HDP and 116,744 matched controls were identified. The overall incidence of HF was greater in the HDP group than it was in the control group (9.83 vs. 1.67 per 10,000 person-years), with a significant incidence rate ratio (IRR = 5.88, 95% confidence interval [CI] 5.84-5.92, p < 0.0001). When stratified by age, parity, gestational age, gestational number, and follow-up years, the IRR for subsequent HF remained significantly higher in the HDP group in all stratifications. Additionally, the Kaplan-Meier analysis indicated that the cumulative incidence rate of HF was higher in the HDP group than it was in the control group. The Cox proportional-hazard model analysis showed that in addition to HDP, single parity, preterm and hypertension were independent risk factors for developing HF. Moreover, HF was more likely to develop within 5 years post-partum. Among patients with a history of HDP, the Cox proportional-hazard model showed that severe forms of HDP and increased HDP occurrences were independently associated with the subsequent development of HF.

CONCLUSIONS

Patients who have experienced HDP presented an increased risk for developing HF later in life. Moreover, among individuals with a history of HDP, those with severe forms of HDP or recurrent HDP displayed an increased subsequent risk of HF.

Associations of Maternal Vitamin D Deficiency with Pregnancy and Neonatal Complications in Developing Countries: A Systematic Review

Pregnant women in Asia, the Middle East, Africa and Latin America are at risk of vitamin D deficiency (VDD) and prevalence throughout these regions are among the highest, globally. Maternal VDD has been associated with increased risk of a number of adverse maternal and neonatal health outcomes, yet research from developing countries is limited. We assessed the associations of maternal VDD during pregnancy with adverse health outcomes by synthesizing the literature from observational studies conducted in developing countries. Six electronic databases were searched for English-language studies published between 2000 and 2017. Thirteen studies from seven countries were included in the review. Prevalence of VDD ranged from 51.3% to 100%. Six studies assessed both maternal and neonatal outcomes, four studies assessed only maternal outcomes and three studies assessed only neonatal outcomes. Ten studies showed at least one significant association between VDD and adverse maternal and/or neonatal health outcomes including pre-eclampsia (n = 3), gestational diabetes mellitus (n = 1), postpartum depression (n = 1), emergency cesarean section delivery (n = 1), low birth weight babies (n = 4), small for gestational age (n = 2), stunting (n = 1). However most of these studies (n = 6) also showed no association with multiple health outcomes. Vitamin D assessment methods, criteria applied to define VDD, season and trimester in which studies were conducted varied considerably across studies. In conclusion, this study highlights the need to improve maternal vitamin D status in developing countries in an effort to support best maternal and child health outcomes across these regions. Future research should focus on more unified approaches to vitamin D assessment and preventative approaches that may be embedded into already existing antenatal care settings.

Meta-Prediction of MTHFR Gene Polymorphisms and Air Pollution on the Risk of Hypertensive Disorders in Pregnancy Worldwide

Hypertensive disorders in pregnancy (HDP) are devastating health hazards for both women and children. Both methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and air pollution can affect health status and result in increased risk of HDP for women. The major objective of this study was to investigate the effect of MTHFR polymorphisms, air pollution, and their interaction on the risk of HDP by using meta-predictive analytics. We searched various databases comprehensively to access all available studies conducted for various ethnic populations from countries worldwide, from 1997 to 2017. Seventy-one studies with 8064 cases and 13,232 controls for MTHFR C677T and 11 studies with 1425 cases and 1859 controls for MTHFR A1298C were included. MTHFR C677T homozygous TT (risk ratio (RR) = 1.28, p < 0.0001) and CT plus TT (RR = 1.07, p = 0.0002) were the risk genotypes, while wild-type CC played a protective role (RR = 0.94, p = 0.0017) for HDP. The meta-predictive analysis found that the percentage of MTHFR C677T TT plus CT (p = 0.044) and CT (p = 0.043) genotypes in the HDP case group were significantly increased with elevated levels of air pollution worldwide. Additionally, in countries with higher air pollution levels, the pregnant women with wild-type CC MTHFR 677 had a protection effect against HDP (p = 0.014), whereas, the homozygous TT of MTHFR C677T polymorphism was a risk genotype for developing HDP. Air pollution level is an environmental factor interacting with increased MTHFR C677T polymorphisms, impacting the susceptibility of HDP for women.

Pregnancy complications in Brazilian puerperal women treated in the public and private health systems

Objective:

to analyze the prevalence of pregnancy complications and sociodemographic profile of puerperal patients with complications, according to the form of financing of the childbirth service.

Method:

cross-sectional study with interview of 928 puerperal women whose childbirth was financed by the Unified Health System, health plans and private sources (other sources than the Unified Health System). The sample was calculated based on the births registered in the Information System on Live Births, stratified by hospital and form of financing of the childbirth service. Data were analyzed using the chi-square and Fisher’s exact tests.

Results:

the prevalence was 87.8% for all puerperal women, with an average of 2.4 complications per woman. In the case of deliveries covered by the Unified Health System, urinary tract infection (38.2%), anemia (26.0%) and leucorrhea (23.5%) were more frequent. In turn, vaginal bleeding (26.4%), urinary tract infection (23.9%) and leucorrhoea (23.7%) were prevalent in deliveries that were not covered by the Unified Health System. Puerperal women that had their delivery covered by the Unified Health System reported a greater number of intercurrences related to infectious diseases, while women who used health plans and private sources reported intercurrences related to chronic diseases. A higher frequency of puerperal adolescents, non-white women, and women without partner among those assisted in the Unified Health System (p < 0.001).

Conclusion:

the high prevalence of complications indicates the need for monitoring and preventing diseases during pregnancy, especially in the case of pregnant women with unfavorable sociodemographic characteristics.

Postpartum Sequelae of the Hypertensive Diseases of Pregnancy: A Pilot Study

Background

Hypertensive disorders are one of the most common medical conditions that may complicate pregnancy. Postpartum blood pressure (BP) pattern is, however, less clear in affected women and decision to discharge them is usually decided arbitrarily.

Materials and Methods

A cohort study conducted at Lagos University Teaching Hospital, Lagos, Nigeria, aimed at determining the proportion of pregnant women with pregnancy-induced hypertension (PIH) and preeclampsia (PE) whose BP remains elevated 6 weeks postdelivery and factors associated with the persistent rise. Fifteen women each with PIH and PE were studied in different phases of pregnancy and followed up until 6 weeks postdelivery. Fifteen normotensive pregnant women served as controls. BP patterns were monitored and fasting lipid levels, serum creatinine, fasting glucose profile (FGP), and FGP/insulin ratio were assayed. Data were analyzed with IBM SPSS version 20.

Results

Proportion of women with PIH or PE who had persistent hypertension at 6 weeks postpartum was 3/29 (10.3%), risk ratio of 1.1. No statistically significant association was found between mean arterial BP at 6 weeks postpartum and age, parity, gestational age at delivery, body mass index, and family history of hypertension. Serum creatinine level showed moderate correlation with persistent hypertension at 6 weeks postpartum (r = 0.441,P = 0.006), with sensitivity of 100% and specificity of 81.8% at cutoff value of 1.2 mg/dL in detecting pregnant women with hypertensive disorders who will likely remain hypertensive at 6 weeks postpartum.

Conclusion

There is a need for long-term follow-up of women with PIH/PE beyond puerperium.

Hypertensive disorders of pregnancy: a strong risk factor for subsequent hypertension 5 years after delivery

Hypertensive disorders of pregnancy are known to be a risk factor for future cardiovascular diseases. In contrast, there is a paucity of data on the not so distant future prognosis of hypertensive disorders of pregnancy. In the present study, we evaluated the incidence of the diseases causing cardiovascular problems (hypertension, diabetes mellitus, dyslipidemia and metabolic syndrome) 5 years after delivery in Japanese women with hypertensive disorders of pregnancy. We performed a double-cohort study and compared medical conditions between women with and without a history of hypertensive disorders of pregnancy. A total of 1513 women who participated in the cohort study were invited to undergo a medical checkup 5 years after the index delivery, of whom 829 responded. After excluding pregnant and lactating women at the time of examination, 25 women with hypertensive disorders of pregnancy and 746 control subjects were analyzed. The incidence of hypertension was significantly higher among women with hypertensive disorders of pregnancy than women who were normotensive during pregnancy (24.0 vs. 2.5%, P<0.001). They were also at an increased risk of subsequent hypertension 5 years after the index delivery, after adjusting for confounding factors such as age, body mass index, family history of hypertension and salt intake (odds ratio 7.1, 95% CI, 2.0-25.6, P<0.003). These is no significant difference in the incidence of diabetes mellitus, dyslipidemia and metabolic syndrome. In conclusion, hypertensive disorders of pregnancy are strong risk factors for subsequent hypertension only 5 years after delivery.

Stroke in women - from evidence to inequalities

Stroke is the second largest cause of disability-adjusted life-years lost worldwide. The prevalence of stroke in women is predicted to rise rapidly, owing to the increasing average age of the global female population. Vascular risk factors differ between women and men in terms of prevalence, and evidence increasingly supports the clinical importance of sex differences in stroke. The influence of some risk factors for stroke - including diabetes mellitus and atrial fibrillation - are stronger in women, and hypertensive disorders of pregnancy also affect the risk of stroke decades after pregnancy. However, in an era of evidence-based medicine, women are notably under-represented in clinical trials - despite governmental actions highlighting the need to include both men and women in clinical trials - resulting in a reduced generalizability of study results to women. The aim of this Review is to highlight new insights into specificities of stroke in women, to plan future research priorities, and to influence public health policies to decrease the worldwide burden of stroke in women.

Myeloperoxidase in Hypertensive Disorders of Pregnancy and Its Relation With Nitric Oxide

Elevated levels of myeloperoxidase have been demonstrated in women with preeclampsia where it may contribute to endothelial dysfunction mediated, in part, by nitric oxide impairment. In this study, we investigated myeloperoxidase in hypertensive disorders of pregnancy and its contribution to the impairment of the vasodilator nitric oxide. We found higher levels of myeloperoxidase in supernatant from human umbilical vein endothelial cells cultures incubated with plasma from preeclampsia group compared with healthy pregnant women. Further, we measured plasma concentration and activity of myeloperoxidase in 219 healthy pregnant women, 130 gestational hypertension (on antihypertensive therapy or not), and 143 preeclampsia patients (on antihypertensive therapy or not). We found that patients with preeclampsia and gestational hypertension without antihypertensive treatment showed higher levels and activity of this enzyme, respectively. Moreover, the inhibition of myeloperoxidase activity in vitro improved nitric oxide bioavailability. Our results indicate a higher cardiovascular risk in pregnant women with hypertensive disorders, and that active myeloperoxidase may play a role in endothelial dysfunction in these conditions by impairment of nitric oxide availability. Besides, the use of antihypertensive drugs seems to decrease enzyme levels suggesting a new protective feature for these drugs.

Pharmacogenetics in the treatment of pre-eclampsia: current findings, challenges and perspectives

Pre-eclampsia (PE) is defined as pregnancy-induced hypertension and proteinuria, and is a major cause of maternal and perinatal morbidity and mortality. A large subgroup of pregnant women with PE is nonresponsive to antihypertensive drugs, including methyldopa, nifedipine and hydralazine. Pharmacogenomics may help to guide the individualized therapy for this nonresponsive subgroup. However, just a few pharmacogenetic studies examined the effects of genetic polymorphisms on response to antihypertensive drugs in PE, and the criteria of responsiveness used to define responsive or nonresponsive subgroups to antihypertensive therapy should be replicated by others. We review these gene–drugs interactions, novel approaches to pharmacogenomics research and potential novel drugs for PE therapy. Finally, we discuss the challenges and perspectives of pharmacogenetics in the treatment of PE.