Increased incidence of bronchopulmonary dysplasia in preterm infants exposed to preeclampsia

The relationship between severe hypertensive diseases of pregnancy and moderate-severe bronchopulmonary dysplasia

OBJECTIVE

Determine the association between severe hypertensive disease of pregnancy (HDP) with moderate-severe bronchopulmonary dysplasia (BPD) in preterm infants (< 31 weeks' gestation).

STUDY DESIGN

Preterm birth cohort study of 693 mother-infant dyads. Severe HDP was defined as severe preeclampsia, HELLP syndrome or eclampsia. The outcome was moderate-severe BPD classified at 36 weeks corrected gestational age, per the NICHD Consensus statement.

RESULTS

225 (32%) mothers developed severe HDP and 234 (34%) infants had moderate-severe BPD. There was an interaction between severe HDP and gestational age (p = 0.03). Infants born at < 25 weeks gestation to mothers with HDP had increased odds for moderate-severe BPD compared to infants of normotensive mothers delivering at the same gestational age. Infants born > 28 weeks to mothers with severe HDP had decreased odds for the outcome, though not statistically significant.

CONCLUSIONS

Severe HDP has a differential effect on the development of moderate-severe BPD based on gestational age.

Neonatal outcomes of early preterm births according to the delivery indications

OBJECTIVE

To compare the neonatal outcomes of early preterm births according to delivery indications and determine the obstetric risk factors associated with adverse outcomes.

METHODS

We retrospectively studied pregnancies delivered between 22 + 0 and 26 + 6 weeks at the tertiary center between April 2013 and April 2022. Stillbirths, elective termination of pregnancy, and multifetal pregnancies were excluded. Patients were classified into two groups according to delivery indications: spontaneous preterm birth (sPTB) due to premature rupture of membranes (PROM), preterm labor, or acute cervical insufficiency; and indicated preterm birth (iPTB). Obstetric and neonatal outcomes were compared between the groups.

RESULTS

Of the 121 neonates, 73 % (88/121) underwent sPTB. The overall survival rates were 73 % and 49 % in the sPTB and iPTB groups, respectively (p = 0.017). Multivariate logistic regression analysis was performed with adjustment for gestational age at delivery, fetal growth restriction, cesarean section, histological chorioamnionitis, and funisitis. Moreover, in the 1-year follow-up, the proportion of body mass below the third percentile was significantly higher in the iPTB-group than in the sPTB-group (53 % vs. 20 %, p = 0.019). Furthermore, diagnoses of developmental delay and cerebral palsy were slightly higher in the iPTB-group (33 % and 20 %, respectively) than in the sPTB-group (27 % and 9 %, respectively); however, this difference was not statistically significant.

CONCLUSIONS

In early preterm births, iPTB was associated with a higher neonatal mortality than sPTB.

Mesenchymal stromal/stem cells and bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a common complication in preterm infants, leading to chronic respiratory disease. There has been an improvement in perinatal care, but many infants still suffer from impaired branching morphogenesis, alveolarization, and pulmonary capillary formation, causing lung function impairments and BPD. There is an increased risk of respiratory infections, pulmonary hypertension, and neurodevelopmental delays in infants with BPD, all of which can lead to long-term morbidity and mortality. Unfortunately, treatment options for Bronchopulmonary dysplasia are limited. A growing body of evidence indicates that mesenchymal stromal/stem cells (MSCs) can treat various lung diseases in regenerative medicine. MSCs are multipotent cells that can differentiate into multiple cell types, including lung cells, and possess immunomodulatory, anti-inflammatory, antioxidative stress, and regenerative properties. MSCs are regulated by mitochondrial function, as well as oxidant stress responses. Maintaining mitochondrial homeostasis will likely be key for MSCs to stimulate proper lung development and regeneration in Bronchopulmonary dysplasia. In recent years, MSCs have demonstrated promising results in treating and preventing bronchopulmonary dysplasia. Studies have shown that MSC therapy can reduce inflammation, mitochondrial impairment, lung injury, and fibrosis. In light of this, MSCs have emerged as a potential therapeutic option for treating Bronchopulmonary dysplasia. The article explores the role of MSCs in lung development and disease, summarizes MSC therapy's effectiveness in treating Bronchopulmonary dysplasia, and delves into the mechanisms behind this treatment.

The Relationship Between Severe Hypertensive Diseases of Pregnancy and Moderate-Severe Bronchopulmonary Dysplasia

Objective

Determine the association between severe hypertensive disease of pregnancy (HDP) with moderate-severe bronchopulmonary dysplasia (BPD) in preterm infants (< 31 weeks' gestation).

Study Design

Preterm birth cohort study of 693 mother-infant dyads. Severe HDPwas defined as severe preeclampsia, HELLP syndrome or eclampsia. The outcome was moderate-severe BPD classified at 36 weeks corrected gestational age, based on the NICHD Consensusstatement.

Results

225 (32%) mothers developed severe HDP and 234 (34%) infants hadmoderate-severe BPD. There was an interaction between severe HDP and gestational age (p=0.03). Infants born at earlier gestational ages to mothers with HDP had increased odds for moderate-severe BPD compared to infants of normotensive mothers delivering at the same gestational age. Infants born at later gestational ages to mothers with severe HDP had decreased odds for the outcome.

Conclusions

Severe HDP has a differential effect on the development of moderate-severe BPD based on gestational age.

Short- and Long-Term Outcomes of Preeclampsia in Offspring: Review of the Literature

Preeclampsia is a multisystemic clinical syndrome characterized by the appearance of new-onset hypertension and proteinuria or hypertension and end organ dysfunction even without proteinuria after 20 weeks of pregnancy or postpartum. Residing at the severe end of the spectrum of the hypertensive disorders of pregnancy, preeclampsia occurs in 3 to 8% of pregnancies worldwide and is a major cause of maternal and perinatal morbidity and mortality, accounting for 8-10% of all preterm births. The mechanism whereby preeclampsia increases the risk of the neurodevelopmental, cardiovascular, and metabolic morbidity of the mother's offspring is not well known, but it is possible that the preeclamptic environment induces epigenetic changes that adversely affect developmental plasticity. These developmental changes are crucial for optimal fetal growth and survival but may lead to an increased risk of chronic morbidity in childhood and even later in life. The aim of this review is to summarize both the short- and long-term effects of preeclampsia on offspring based on the current literature.

Consequences of early-onset preeclampsia on neonatal morbidity and mortality

Preterm birth is the leading cause of perinatal morbidity and mortality in developed countries. Common reasons for indicated preterm births include pre-eclampsia. The increase in incidences of morbidity and mortality observed in neonates resulting from pregnancies complicated by preeclampsia is also due to alterations in angiogenic and pro-inflammatory factors that directly affect the neonatal health. This review was prepared with the aim of gathering the information available at PubMed/MEDLINE, in the years from 2011 to 2021, on the consequences of neonatal morbidity and mortality of early-onset preeclampsia. There is great controversy in the literature and paucity of studies. Early onset pre-eclampsia has been linked to fetal growth restriction (FGR). Most studies support its association with respiratory distress syndrome (RDS). Most studies point to an association between preeclampsia and bronchopulmonary dysplasia (BPD), with the highest risk in FGR. The association between preeclampsia, patent ductus arteriosus (PDA) and sepsis is not supported by the literature. The association to necrotizing enterocolitis (NEC) is controversial. The risk of spontaneous intestinal perforation (SIP) seems to be increased with preeclampsia. The association between intraventricular hemorrhage (IVH) and preeclampsia is controversial, however, preeclampsia seems to have a protective effect on periventricular leukomalacia (PVL). Most of the evidence points to the non-association between preeclampsia and retinopathy of prematurity (ROP). Hematological changes such as neutropenia, thrombocytopenia and increased nucleated red blood cell counts have been shown to be associated with preeclampsia. The evidence is still quite controversial regarding mortality. The early installation of preeclampsia will have direct consequences on neonatal morbidity. Gestational age at preterm birth is the main risk factor on neonatal morbidity. Obstetricians should aim to prolong the pregnancies complicated by early-onset severe preeclampsia as far as maternal conditions allow. This policy may contribute to improve the neonatal outcomes.

Understanding the role of placental pathophysiology in the development of bronchopulmonary dysplasia

The associations between bronchopulmonary dysplasia (BPD) and the gestational pathologies of chorioamnionitis (CA) and hypertensive disorders of pregnancy (HDP) have become increasingly well recognized. However, the mechanisms through which these antenatal conditions cause increased risk of BPD remain less well characterized. The objective of this review is to discuss the role of the placenta in BPD predisposition as a primary driver of intrauterine alterations adversely impacting fetal lung development. We hypothesize that due to similarities in structure and function, placental disorders during pregnancy can uniquely impact the developing fetal lung, creating a unique placental-pulmonary connection. In the current review, we explore this hypothesis through analysis of clinical literature and preclinical model systems evaluating BPD predisposition, discussion of BPD phenotypes, and an overview on strategies to incorporate placental investigation into research on fetal lung development. We also discuss important concepts learned from research on antenatal steroids as a modulator fetal lung development. Finally, we propose that the appropriate selection of animal models and establishment of in vitro lung developmental model systems incorporating primary human placental components are key in continuing to understand and address antenatal predisposition to BPD.

Adverse Neonatal Outcome of Pregnancies Complicated by Preeclampsia

Despite many available treatments, infants born to preeclamptic mothers continue to pose a serious clinical problem. The present study focuses on the evaluation of infants born to preeclamptic mothers for the occurrence of early-onset complications and attempts to link the clinical status of such infants to the angiogenesis markers in maternal blood (sFlt-1, PlGF). The study included 77 newborns and their mothers diagnosed with preeclampsia. The infants were assessed for their perinatal outcomes, with an emphasis on adverse neonatal outcomes such us infections, RDS, PDA, NEC, IVH, ROP, or BPD during the hospitalization period. The cutoff point was established using the ROC curve for the occurrence of any adverse neonatal outcome and it was 204 for the sFlt-1/PlGF and 32 birth week with AOC 0.644 and 0.91, respectively. The newborns born to mothers with high ratios had longer hospitalization times and, generally, were more frequently diagnosed with any of the aforementioned adverse neonatal outcomes. Also, the neonates born prior to or at 32 wkGA with higher sFlt-1/PlGF ratios were statistically significantly more common to be diagnosed with any of the adverse neonatal outcomes compared to those with lower ratio born prior to or at 32 wkGA. The sFlt-1/PlGF ratio can be a useful tool in predicting short-term adverse neonatal outcomes. Infants born after a full 33 weeks gestation developed almost no severe neonatal complications. Appropriate screening and preventive healthcare for preeclampsia can contribute significantly to reducing the incidence of neonatal complications.

Association of Maternal Hypertensive Disorders During Pregnancy With Severe Bronchopulmonary Dysplasia: A Systematic Review and Meta-Analysis

BACKGROUND

This meta-analysis was performed to examine the association between maternal hypertension during pregnancy (HDP) and neonatal bronchopulmonary dysplasia (BPD).

METHODS

We systematically searched PubMed, EMBASE, the Cochrane Library, and the KoreaMed database for relevant studies. We used the Newcastle-Ottawa Scale for quality assessment of all included studies. The meta-analysis was performed using Comprehensive Meta-Analysis software (version 3.3).

RESULTS

We included 35 studies that fulfilled the inclusion criteria; the total number of infants evaluated came to 97,399 through review process. Maternal HDP was not significantly associated with any definition of BPD, i.e., oxygen dependency at 36 weeks of gestation (odds ratio [OR], 1.162; 95% confidence interval [CI], 0.991-1.362; P = 0.064) in pooled analysis of 29 studies or oxygen dependency at 28 days of age (OR, 1.084; 95% CI, 0.660-1.780; P = 0.751) in pooled analysis of 8 studies. Maternal HDP was significantly associated only with severe BPD (OR, 2.341; 95% CI, 1.726-3.174; P < 0.001). BPD was not associated with HDP in the overall analysis (OR, 1.131; 95% CI, 0.977-1.309; P = 0.100) or subgroup analysis according to the definition of HDP.

CONCLUSION

Maternal HDP was not associated with neonatal BPD defined by the duration of oxygen dependency (at either 36 weeks of gestation or 28 days of life) but was associated with severe BPD.

Chronic Inflammatory Placental Lesions Correlate With Bronchopulmonary Dysplasia Severity in Extremely Preterm Infants

OBJECTIVE

Correlation of BPD with placental pathology is important for clarification of the multifactorial pathogenesis of BPD; however, previous reports have yielded varying results. We report placental findings in no/mild BPD compared to moderate/severe BPD, and with and without pulmonary hypertension (PH).

METHODS

Eligible infants were 23^0/7-27^6/7 weeks gestational age. BPD was defined by the need for oxygen at ≥28 days with severity based on need for respiratory support at ≥36 weeks. Acute and chronic inflammatory placental lesions and lesions of maternal and fetal vascular malperfusion were examined.

RESULTS

Of 246 eligible infants, 146 (59%) developed moderate/severe BPD. Thirty-four (23%) infants developed PH, all but 1 being in the moderate/severe BPD group. Chronic deciduitis (32% vs 16%, P = .003), chronic chorioamnionitis (23% vs 12%, P = .014), and ≥ 2 chronic inflammatory lesions (13% vs 3%, P = .007) were more frequent in the moderate/severe BPD group. Development of PH was associated with placental villous lesions of maternal vascular malperfusion (30% vs 15%, P = .047).

CONCLUSIONS

The association of chronic inflammatory placental lesions with BPD severity has not been previously reported. This supports the injury responsible for BPD as beginning before birth in some neonates, possibly related to cytokines associated with these chronic inflammatory lesions.

Weighted gene coexpression network reveals downregulation of genes in bronchopulmonary dysplasia

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a serious lung disease observed in premature infants, known to cause considerable morbidity and mortality. Its prognosis is influenced by a complex network of genetic interactions. In this study, we determined the potential key factors in the pathogenesis of this condition.

METHODS

We constructed scale-free gene coexpression network using weighted gene coexpression network analysis. The analysis was carried out on the GSE8586 dataset, which contains the expression profiles of umbilical cord tissue homogenates from 20 neonates with BPD and 34 unaffected controls.

RESULTS

Our analysis identified one significantly downregulated coexpression module related to the BPD phenotype. It was significantly enriched in genes related to human T-cell leukemia virus infection and the mitogen-activated protein kinase pathway. In this module, the expression of the following four hub genes in infants with BPD was significantly decreased: Fos proto-oncogene (FOS), BTG antiproliferation factor 2 (BTG2), Jun proto-oncogene (JUN), and early growth response protein 1 (EGR1). The downregulation of these hub genes was verified in clinical samples derived from blood and umbilical cord tissue.

CONCLUSION

The decreased expression of FOS, BTG2, JUN, and EGR1 is associated with BPD and, therefore, could be used as biomarkers to diagnose early BPD.

Present and Future of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is the most common respiratory disorder among infants born extremely preterm. The pathogenesis of BPD involves multiple prenatal and postnatal mechanisms affecting the development of a very immature lung. Their combined effects alter the lung's morphogenesis, disrupt capillary gas exchange in the alveoli, and lead to the pathological and clinical features of BPD. The disorder is ultimately the result of an aberrant repair response to antenatal and postnatal injuries to the developing lungs. Neonatology has made huge advances in dealing with conditions related to prematurity, but efforts to prevent and treat BPD have so far been only partially effective. Seeing that BPD appears to have a role in the early origin of chronic obstructive pulmonary disease, its prevention is pivotal also in long-term respiratory outcome of these patients. There is currently some evidence to support the use of antenatal glucocorticoids, surfactant therapy, protective noninvasive ventilation, targeted saturations, early caffeine treatment, vitamin A, and fluid restriction, but none of the existing strategies have had any significant impact in reducing the burden of BPD. New areas of research are raising novel therapeutic prospects, however. For instance, early topical (intratracheal or nebulized) steroids seem promising: they might help to limit BPD development without the side effects of systemic steroids. Evidence in favor of stem cell therapy has emerged from several preclinical trials, and from a couple of studies in humans. Mesenchymal stromal/stem cells (MSCs) have revealed a reparatory capability, preventing the progression of BPD in animal models. Administering MSC-conditioned media containing extracellular vesicles (EVs) have also demonstrated a preventive action, without the potential risks associated with unwanted engraftment or the adverse effects of administering cells. In this paper, we explore these emerging treatments and take a look at the revolutionary changes in BPD and neonatology on the horizon.

The Association of Pregnancy-induced Hypertension with Bronchopulmonary Dysplasia - A Retrospective Study Based on the Korean Neonatal Network database

The prevalence of pregnancy-induced hypertension (PIH) and preeclampsia (PE) are 5-10% and 2-4%, respectively. PIH might affect angiogenesis in preterm neonates, but its association with bronchopulmonary dysplasia (BPD) remains controversial. This study evaluated the association between PIH and BPD in very low-birth weight infants. We retrospectively analysed the maternal, perinatal, and neonatal data of preterm infants born before 30 weeks of gestation, selected from the nationwide registry of very low-birth weight infants, between January 2013 and December 2014. As a result, 1,624 infants without maternal PIH (gestational age: 27.3 ± 1.8 weeks) and 203 infants with maternal PIH (28.0 ± 1.4 weeks, p < 0.001) were included. Birth weight was higher in the non-PIH group, compared with the PIH group (1027.4 ± 250.2 vs. 876.4 ± 261.5 g, p < 0.001). Multivariate logistic regression showed that PIH was associated with BPD (adjusted OR 1.474, 95% confidence interval 1.025-2.121), after adjusting for confounders, including small-for-gestation age (SGA). The result of present study is consistent with the current concept of BPD as an early form of pulmonary vascular disease, for both PIH and BPD are attributed by abnormal vascular formation.

Neonatal Outcome After Preeclampsia and HELLP Syndrome: A Population-Based Cohort Study in Germany

Aim: To analyze short term outcomes of very low birth weight infants (VLBWI) born preterm after maternal preeclampsia and HELLP syndrome within the German Neonatal Network. Methods: The German Neonatal Network is a large population-based cohort study enrolling VLBWI since 2009. Two thousand six hundred and fifty two infants below 32 weeks of gestation born after maternal preeclampsia or HELLP syndrome and 13,383 infants born prematurely for other causes between 2009 and 2018 were included in our analysis. Descriptive statistics and multinomial regression models including preeclampsia and HELLP syndrome were performed for short-term outcome measures such as intracerebral hemorrhage, necrotizing enterocolitis requiring surgery, bronchopulmonary dysplasia, retinopathy of prematurity, periventricular leukomalacia, persistent ductus arteriosus requiring surgery, blood culture positive sepsis and death. Results: After adjustment for confounding variables, preterm birth due to preeclampsia or HELLP syndrome was associated with a reduced risk for intracerebral hemorrhage (OR 0.73, 95% CI 0.60-0.89), necrotizing enterocolitis requiring surgery (OR 0.35 95% CI 0.15-0.82), periventricular leukomalacia (OR 0.61 95% CI 0.40-0.92), and death (OR 0.72 95% CI 0.55-0.96) as compared to other causes of preterm birth. Conclusions: The indication for preterm birth has an impact on neonatal outcome in preterm infants born below 32 weeks. This notion should be included when counseling the families.

Oxygen radical disease in the newborn, revisited: Oxidative stress and disease in the newborn period

Thirty years ago, there was an emerging appreciation for the significance of oxidative stress in newborn disease. This prompted a renewed interest in the impact of oxygen therapy for the newborn in the delivery room and beyond, especially in premature infants. Today, the complexity of oxidative stress both in normal regulation and pathology is better understood, especially as it relates to neonatal mitochondrial oxidative stress responses to hyperoxia. Mitochondria are recipients of oxidative damage and have a propensity for oxidative self-injury that has been implicated in the pathogenesis of neonatal lung diseases. Similarly, both intrauterine growth restriction (IUGR) and macrosomia are associated with mitochondrial dysfunction and oxidative stress. Additionally, reoxygenation with 100% O₂ in a hypoxic-ischemic newborn lamb model increased the production of pro-inflammatory cytokines in the brain. Moreover, the interplay between inflammation and oxidative stress in the newborn is better understood because of animal studies. Transcriptomic analyses have found a number of genes to be differentially expressed in murine models of bronchopulmonary dysplasia (BPD). Epigenetic changes have also been detected both in animal models of BPD and premature infants exposed to oxygen. Antioxidant therapy to prevent newborn disease has not been very successful; however, new therapeutic principles, like melatonin, are under investigation.

Anti-sFlt-1 Therapy Preserves Lung Alveolar and Vascular Growth in Antenatal Models of Bronchopulmonary Dysplasia

RATIONALE

Pregnancies complicated by antenatal stress, including preeclampsia (PE) and chorioamnionitis (CA), increase the risk for bronchopulmonary dysplasia (BPD) in preterm infants, but biologic mechanisms linking prenatal factors with BPD are uncertain. Levels of sFlt-1 (soluble fms-like tyrosine kinase 1), an endogenous antagonist to VEGF (vascular endothelial growth factor), are increased in amniotic fluid and maternal blood in PE and associated with CA.

OBJECTIVES

Because impaired VEGF signaling has been implicated in the pathogenesis of BPD, we hypothesized that fetal exposure to sFlt-1 decreases lung growth and causes abnormal lung structure and pulmonary hypertension during infancy.

METHODS

To test this hypothesis, we studied the effects of anti-sFlt-1 monoclonal antibody (mAb) treatment on lung growth in two established antenatal models of BPD that mimic PE and CA induced by intraamniotic (i.a.) injections of sFlt-1 or endotoxin, respectively. In experimental PE, mAb was administered by three different approaches, including antenatal treatment by either i.a. instillation or maternal uterine artery infusion, or by postnatal intraperitoneal injections.

RESULTS

With each strategy, mAb therapy improved infant lung structure as assessed by radial alveolar count, vessel density, right ventricular hypertrophy, and lung function. As found in the PE model, the adverse lung effects of i.a. endotoxin were also reduced by antenatal or postnatal mAb therapy.

CONCLUSIONS

We conclude that treatment with anti-sFlt-1 mAb preserves lung structure and function and prevents right ventricular hypertrophy in two rat models of BPD of antenatal stress and speculate that early mAb therapy may provide a novel strategy for the prevention of BPD.

Hypertensive Disorders of Pregnancy

Hypertensive disorders of pregnancy are common and contribute inordinately to maternal and fetal morbidity and mortality. Although not completely understood, recent clinical trials have provided important insights into pathogenesis of preeclampsia. Preeclampsia is considered a systemic disease with generalized endothelial dysfunction and risk of future cardiovascular disease. This review revisits the definitions and classifications of hypertensive disorders of pregnancy; discusses updates on pathophysiology, prevention, and early prediction of preeclampsia; reviews current management guidelines; and discusses potential risks and benefits associated with treatment. Improvement in management and outcomes of women with hypertensive disorders of pregnancy seems in sight in the near future.

Maternal preeclampsia and respiratory outcomes in extremely premature infants

BACKGROUND

Preeclampsia (PE) is a pregnancy complication characterized by an anti-angiogenic environment. This can affect fetal pulmonary vascular and alveolar development but data of the impact of PE on respiratory outcome in extremely premature infants are inconclusive. The objective of this study was to determine if PE is associated with an increased risk for severe respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD) in extremely premature infants.

METHODS

Prospectively collected single center data from a cohort of infants born at 23-28 w gestational age between January 2005 and December 2015 were analyzed. Logistic regression analysis and generalized estimating equations were used to model the association between PE and severe RDS (≥30% supplemental oxygen on d1), BPD and severe BPD [supplemental oxygen and ≥30% oxygen at 36 w postmenstrual age (PMA), respectively].

RESULTS

The cohort included 1218 infants of whom 23% were exposed to PE. PE was associated with increased risk for severe RDS as well as severe BPD among infants alive at 36w PMA.

CONCLUSION

Exposure to preeclampsia is independently associated with an increased risk for severe RDS and adverse respiratory outcome in extreme premature infants. The mechanisms behind these associations need to be investigated.

Preeclampsia and risk of developing bronchopulmonary dysplasia in very preterm neonates

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is a severe common complication of preterm birth with considerable short and long-term consequences. As more evidence is emerging that dysregulation of angiogenesis is implicated in the pathogenesis of preeclampsia as well as in fetal lung development, we assessed if preeclampsia is associated with development of BPD in very preterm neonates.

STUDY DESIGN

A retrospective cohort study of 308 infants born between 24⁺⁰ and 31⁺⁶ weeks of gestation in 2011 and 2012. We performed association analysis with univariable and multivariable logistic regression, adjusting for confounders. Models were additionally adjusted for intermediates, to show how an association can be disguised by over adjusting.

MAIN OUTCOME MEASURE

BPD was diagnosed at 36⁺⁰ weeks postmenstrual age and defined as the need for oxygen (FiO2 > 0.21) for at least 12 h per day, for more than 28 days before or at 36⁺⁰ weeks postmenstrual age, and classified as mild, moderate or severe.

RESULTS

After applying our exclusion criteria, we report our primary outcome on 247 mother-neonate pairs. Fifty-nine neonates developed BPD (23.9%) which was moderate to severe in 27 of them (10.9%). Preeclampsia was associated with BPD, adjusted odds ratio, 95% confidence interval: 4.22 (1.63, 10.91). However, after adjusting for additional intermediates no statistical significance remained, adjusted odds ratio, 95% confidence interval: 1.87 (0.49, 7.24).

CONCLUSION

This study shows that early-onset preeclampsia is associated with development of BPD in the very preterm neonate. Part of this association is mediated by fetal growth restriction and mode of delivery.

Bronchopulmonary dysplasia in neonates born to mothers with preeclampsia: Impact of small for gestational age

Background and objectives

Small for gestational age and preeclampsia have both been described as risk factors for bronchopulmonary dysplasia in preterm neonates, but their respective role in the occurrence of bronchopulmonary dysplasia is debated. We evaluated the relation between small for gestational age and bronchopulmonary dysplasia in neonates born to mothers with preeclampsia. We hypothesized that low birth weight is still associated with bronchopulmonary dysplasia in this homogeneous population.

Methods

Retrospective single-center cohort study including 141 neonates born between 24 and 30 weeks’ gestation to mothers with preeclampsia. The main outcome measure was moderate to severe bronchopulmonary dysplasia at 36 weeks’ postmenstrual age. Neonates born small for gestational age (birthweight < 10^th percentile on the AUDIPOG curves) were compared to those with appropriate birthweight for gestational age by bivariable analyses and logistic regression models, estimating odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Bronchopulmonary dysplasia rates were 61.5% (32/52) and 27.4% (20/73) for small for gestational age and appropriate birthweight for gestational age neonates (p < .001). On adjustment for gestational age and other confounding factors, the risk of moderate to severe bronchopulmonary dysplasia was greater for small for gestational age than appropriate birthweight for gestational age neonates (adjusted OR = 5.9, 95% CI [2.2–15.4]), as was the composite outcome death or moderate to severe bronchopulmonary dysplasia (adjusted OR = 4.7, 95% CI [1.9–11.3]).

Conclusions

Small for gestational age was associated with bronchopulmonary dysplasia in very preterm neonates born to mothers with preeclampsia.

Registration number

CNIL no. 1747084.

Preeclampsia predicts higher incidence of bronchopulmonary dysplasia

INTRODUCTION

It is not known whether very preterm infants born to preeclamptic women have worse outcomes than those delivered preterm for other causes.

OBJECTIVE

We assessed the association between preeclampsia (PE) and the neonatal morbidity and mortality of very preterm infants.

METHODS

Over 2015 and 2016, 11 collaborating Portuguese level III NICUs prospectively enrolled a cohort of mothers with or without PE who delivered liveborn premature infants between 24 and 30 completed weeks of gestation. Data on neonatal morbidities were collected and their association to PE was assessed.

RESULTS

The final cohort consisted of 410 mothers who delivered 494 preterm infants. Infants from PE mothers weighed less than those of non-PE mothers (819 ± 207 g vs. 989 ± 256 g, p < 0.0001). Incidences of respiratory distress syndrome, patent ductus arteriosus, early and nosocomial sepsis, necrotizing enterocolitis, pneumonia, meningitis, retinopathy of prematurity, intraventricular hemorrhage, periventricular infarction, periventricular leukomalacia, and mortality did not differ significantly between infants of PE or non-PE mothers. Incidence of bronchopulmonary dysplasia (BPD-defined as oxygen dependency at 36 weeks) was higher in PE infants compared with non-PE infants by both univariate and multivariate logistic regression (p = 0.007).

CONCLUSION

We conclude that, when controlling for gestational age, maternal PE results in higher incidence of only BPD among preterm Portuguese infants.

Association of increased cord blood soluble endoglin with the development of bronchopulmonary dysplasia in preterm infants with maternal preeclampsia

OBJECTIVES

To investigate whether the levels of angiogenic factors in cord blood are associated with the development of bronchopulmonary dysplasia (BPD) in preterm infants with maternal preeclampsia.

STUDY DESIGN

This retrospective cohort study included 199 singleton infants (gestational age < 32 weeks), including the preeclampsia group (59 infants) with severe/moderate BPD (24 infants) or no/mild BPD (35 infants) and the no preeclampsia group (140 infants).

MAIN OUTCOMES MEASURES

The levels of soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin, and placental growth factor (PlGF) in cord blood were measured and compared among the study groups.

RESULTS

The soluble endoglin level and the ratio of (sFlt-1 + soluble endoglin) to PlGF were significantly higher in the preeclampsia group than in the no preeclampsia group (P < .05). Among preterm infants with maternal preeclampsia, both of these parameters were also significantly higher in the severe/moderate BPD group than the no/mild BPD group (P < .05). Receiver operator curve analysis revealed that increased cord blood soluble endoglin was predictive of severe or moderate BPD in preterm infants with maternal preeclampsia (area under the curve 0.73). Gestational age (adjusted odds ratio [OR] 0.25; P < .001) and high soluble endoglin level in cord blood (>3420 pg/mL) (adjusted OR 11.9; P = .006) were significant risk factors for the development of severe or moderate BPD in the preeclampsia group according to multivariate logistic regression analysis.

CONCLUSION

Increased cord blood soluble endoglin is associated with the development of severe or moderate BPD in preterm infants with maternal preeclampsia.

Preeclampsia: Pathogenesis, Prevention, and Long-Term Complications

Preeclampsia continues to afflict 5% to 8% of all pregnancies throughout the world and is associated with significant morbidity and mortality to the mother and the fetus. Although the pathogenesis of the disorder has not yet been fully elucidated, current evidence suggests that imbalance in angiogenic factors is responsible for the clinical manifestations of the disorder, and may explain why certain populations are risk. In this review, we begin by demonstrating the roles that angiogenic factors play in pathogenesis of preeclampsia and its complications in the mother and the fetus. We then continue to report on the use of angiogenic markers as biomarkers to predict and risk-stratify disease. Strategies to treat preeclampsia by correcting the angiogenic balance, either by promoting proangiogenic factors or by removing antiangiogenic factors in both animal and human studies, are discussed. We end the review by summarizing status of the current preventive strategies and the long-term cardiovascular outcomes of women afflicted with preeclampsia.

[Clinical features and prognosis of preterm infants with varying degrees of bronchopulmonary dysplasia]

OBJECTIVE

To study the clinical features and prognosis of preterm infants with varying degrees of bronchopulmonary dysplasia (BPD).

METHODS

The clinical data of 144 preterm infants with a gestational age of <32 weeks who were admitted to the neonatal intensive care unit from March 2014 to March 2016 and were diagnosed with BPD were collected. According to the severity of BPD, these preterm infants were divided into mild group with 81 infants and moderate/severe group with 63 infants. The two groups were compared in terms of perinatal risk factors, treatment, comorbidities, complications, and prognosis of the respiratory system.

RESULTS

Compared with the mild BPD group, the moderate/severe BPD group had a significantly higher gestational age and rate of small-for-gestational-age (SGA) infants (P&lt;0.05), as well as a significantly higher rate of severe preeclampsia and a significantly lower rate of threatened preterm labor (P&lt;0.05). Compared with the mild BPD group, the moderate/severe BPD group had a significantly higher percentage of infants who needed mechanical ventilation at 2 weeks after birth, longer duration of mechanical ventilation, total time of oxygen therapy, and length of hospital stay, and higher incidence rates of pneumonia and cholestasis (P&lt;0.05), as well as a significantly lower application rate of caffeine citrate (P&lt;0.05). The multivariate logistic regression analysis showed that SGA birth (OR=5.974, P&lt;0.05), pneumonia (OR=2.590, P&lt;0.05), and mechanical ventilation required at 2 weeks after birth (OR=4.632, P&lt;0.05) were risk factors for increased severity of BPD. The pulmonary function test performed at the corrected gestational age of 40 weeks showed that compared with the mild BPD group, the moderate/severe BPD group had significantly lower ratio of time to peak tidal expiratory flow to total expiratory time, ratio of volume to peak tidal expiratory flow to total expiratory volume, and tidal expiratory flow at 25% remaining expiration (P&lt;0.05). The infants were followed up to the corrected gestational age of 1 year, and the moderate/severe BPD group had significantly higher incidence rates of recurrent hospital admission for pneumonia and recurrent wheezing (P&lt;0.05).

CONCLUSIONS

SGA birth, pneumonia, and prolonged mechanical ventilation are associated with increased severity of BPD. Infants with moderate or severe BPD have poor pulmonary function and may experience recurrent infection and wheezing.

Pregnancy-induced hypertension and neonatal outcomes: a systematic review and meta-analysis

OBJECTIVE

Pregnancy-induced hypertension (PIH) is associated with preterm delivery but its independent impact on neonatal outcomes remains unclear. We sought to systematically review and meta-analyze clinical outcomes of preterm infants <37 weeks' gestation born to mothers with and without PIH.

STUDY DESIGN

Medline, Embase, PsychINFO and CINAHL were searched from January 2000 to October 2016. Studies with low-moderate risk of bias reporting neonatal outcomes based on PIH as primary exposure variable were included. Data were extracted independently by two co-authors.

RESULTS

PIH was associated with lower mortality (3 studies; adjusted odds ratio (aOR) 0.65; 95% confidence interval (CI) 0.54 to 0.79), lower severe retinopathy of prematurity (ROP) (2 studies; aOR 0.83; 0.72 to 0.96) and lower severe brain injury (2 studies; unadjusted OR (uOR) 0.57; 0.49 to 0.66). No association between PIH and short-term respiratory outcomes, bronchopulmonary dysplasia (BPD) or necrotizing enterocolitis (NEC) was identified. In subgroup analysis among infants <29 weeks' gestation, BPD odds were higher (3 studies; aOR 1.15; 1.06 to 1.26), whereas mortality lower (2 studies; aOR 0.73; 0.69 to 0.77). In subgroup analysis limited to severe PIH, odds of mortality (3 studies; uOR 2.36; 1.07 to 5.22) and invasive ventilation (3 studies; uOR 3.26; 1.11 to 9.61) were higher. In subgroup analysis limited to preeclampsia, odds of BPD (3 studies; uOR 1.21; 95% CI:1.03 to 1.43) and NEC were higher (3 studies; uOR 2.79; 95% CI:1.57 to 4.96).

CONCLUSION

PIH was associated with reduced odds of mortality and ROP (all infants), but higher odds for BPD (<29 weeks' gestation). The paradoxical reduction in mortality may be due to survival bias and deserves further exploration in future studies.

Bronchopulmonary dysplasia-associated pulmonary hypertension: clues from placental pathology

OBJECTIVES

Bronchopulmonary dysplasia (BPD) and the associated complication of pulmonary hypertension (PH) leads to increased mortality and a longer length of stay among survivors. Placental histopathology may give early clues of subsequent events. The objective was to evaluate the relationship of maternal vascular underperfusion (MVU) changes on placental histopathology with subsequent development of BPD-associated PH in a cohort of extremely premature infants.

STUDY DESIGN

In a cohort of preterm infants '⩽28 weeks' gestational age (GA) and with 'severe' BPD, this retrospective study evaluated specific placental histopathological changes and assessed the relationship with subsequent development of PH. 'Severe' BPD was defined as the need for ⩾30% oxygen and/or positive pressure ventilation at 36 weeks postmenstrual age. Placental and echocardiographic assessments were done by investigators masked to the grouping and clinical outcomes.

RESULTS

Fifty six infants with severe BPD formed the cohort; PH was noted in 22 (39.3%) infants. The GA of the infants with and without PH was comparable (25.8±1.6 vs 25.8±1.3 weeks, P=0.9). On placental histopathological examination, 13 (23%) had features of MVU. On univariate logistic regression, the presence of changes consistent with MVU increased the relative risk of subsequent BPD-associated PH by 2.75 (95% confidence interval 1.56 to 4.85, P=0.004). The significance persisted after adjustment for GA. Stratification by the presence or absence of fetal growth restriction, yielded nonsignificant associations (P=0.17).

CONCLUSION

Based on the results of the present study, specific placental histopathological changes may give early clues to the subsequent development of BPD-associated PH.

How does preeclampsia affect neonates? Highlights in the disease's immunity

INTRODUCTION

Preeclampsia (PE) is the primary obstetrical cause in one of the four perinatal deaths. Although the etiology and pathogenesis of preeclampsia is not fully known, a proinflammatory immune state prevails and can disrupt fetal hematopoiesis. Some of the effects on the newborn include neonatal thrombocytopenia, neutropenia, a reduction in T regulatory cells, and an increased cytotoxic natural killer cell profile.

METHODS

Electronic databases were searched, and defined criteria were applied to select articles for review. The review covered literature on the effects on neonatal due to maternal preeclampsia, fetal outcomes, and new treatments in research aimed at reducing morbidity and mortality of the disease.

DISCUSSION

The cytotoxic environment present in PE affects the development of fetal cell lineages. Neutropenia is observed in 50% of neonates and is correlated with mortality, although its treatment is not well-established. The enhancement in erythropoietin and the hypoxic setting present in the disease can also lead to thrombocytopenia. Per partum management includes platelet transfusion in order to avoid severe complications such as intraventricular hemorrhage. Regarding other cell lines, a cytotoxic profile is observed to be reflecting the milieu present in the mothers' bloodstream. This disruption alters the immune system response into a proinflammatory profile and can be correlated to neonatal necrotizing enterocolitis. An antiangiogenic environment is also part of the preeclampsia presentation and can be responsible for the enhancement of bronchopulmonary dysplasia observed in this population. Meanwhile, the reduction in angiogenic factors, such as vascular endothelial growth factor (VEGF), can be a protective mechanism for retinopathy of prematurity. Studies of the long-term effects of these observations are lacking, but lower neurodevelopmental scores and a higher cardiovascular risk are noted. New treatments in research propose a prevention of the disease during gestation in order to reduce the effects more efficiently in the fetus. Phosphodiesterase inhibitors, endothelin 1 receptor antagonists and manipulation of heme oxygenase-1 enzyme pathway are possible therapeutic alternatives. This review summarizes the current understanding of how preeclampsia affects neonates. As a conclusion, further studies are needed to build up a guideline to manage those effects. A research agenda is proposed.

Bronchopulmonary dysplasia: A review of pathogenesis and pathophysiology

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of primarily premature infants that results from an imbalance between lung injury and repair in the developing lung. BPD is the most common respiratory morbidity in preterm infants, which affects nearly 10, 000 neonates each year in the United States. Over the last two decades, the incidence of BPD has largely been unchanged; however, the pathophysiology has changed with the substantial improvement in the respiratory management of extremely low birth weight (ELBW) infants. Here we have attempted to comprehensively review and summarize the current literature on the pathogenesis and pathophysiology of BPD. Our goal is to provide insight to help further progress in preventing and managing severe BPD in the ELBW infants.

Antenatal Determinants of Bronchopulmonary Dysplasia and Late Respiratory Disease in Preterm Infants

RATIONALE

Mechanisms contributing to chronic lung disease after preterm birth are incompletely understood.

OBJECTIVES

To identify antenatal risk factors associated with increased risk for bronchopulmonary dysplasia (BPD) and respiratory disease during early childhood after preterm birth, we performed a prospective, longitudinal study of 587 preterm infants with gestational age less than 34 weeks and birth weights between 500 and 1,250 g.

METHODS

Data collected included perinatal information and assessments during the neonatal intensive care unit admission and longitudinal follow-up by questionnaire until 2 years of age.

MEASUREMENTS AND MAIN RESULTS

After adjusting for covariates, we found that maternal smoking prior to preterm birth increased the odds of having an infant with BPD by twofold (P = 0.02). Maternal smoking was associated with prolonged mechanical ventilation and respiratory support during the neonatal intensive care unit admission. Preexisting hypertension was associated with a twofold (P = 0.04) increase in odds for BPD. Lower gestational age and birth weight z-scores were associated with BPD. Preterm infants who were exposed to maternal smoking had higher rates of late respiratory disease during childhood. Twenty-two percent of infants diagnosed with BPD and 34% of preterm infants without BPD had no clinical signs of late respiratory disease during early childhood.

CONCLUSIONS

We conclude that maternal smoking and hypertension increase the odds for developing BPD after preterm birth, and that maternal smoking is strongly associated with increased odds for late respiratory morbidities during early childhood. These findings suggest that in addition to the BPD diagnosis at 36 weeks, other factors modulate late respiratory outcomes during childhood. We speculate that measures to reduce maternal smoking not only will lower the risk for preterm birth but also will improve late respiratory morbidities after preterm birth.

Placental Complications and Bronchopulmonary Dysplasia: EPIPAGE-2 Cohort Study

OBJECTIVE

To investigate the relationship between placenta-mediated pregnancy complications and bronchopulmonary dysplasia (BPD) in very preterm infants.

METHODS

National prospective population-based cohort study including 2697 singletons born before 32 weeks' gestation. The main outcome measure was moderate to severe BPD. Three groups of placenta-mediated pregnancy complications were compared with no placenta-mediated complications: maternal disorders only (gestational hypertension or preeclampsia), fetal disorders only (antenatal growth restriction), and both maternal and fetal disorders.

RESULTS

Moderate to severe BPD rates were 8% in infants from pregnancies with maternal disorders, 15% from both maternal and fetal disorders, 23% from fetal disorders only, and 9% in the control group (P < .001). When we adjusted for gestational age, the risk of moderate to severe BPD was greater in the groups with fetal disorders only (odds ratio [OR] = 6.6; 95% confidence interval [CI], 4.1-10.7), with maternal and fetal disorders (OR = 3.7; 95% CI, 2.5-5.5), and with maternal disorders only (OR = 1.7; 95% CI, 1.0-2.7) than in the control group. When we also controlled for birth weight, the relationship remained in groups with fetal disorders only (OR = 4.2; 95% CI, 2.1-8.6) and with maternal and fetal disorders (OR = 2.1; 95% CI, 1.1-3.9).

CONCLUSIONS

Placenta-mediated pregnancy complications with fetal consequences are associated with moderate to severe BPD in very preterm infants independently of gestational age and birth weight, but isolated maternal hypertensive disorders are not. Fetal growth restriction, more than birth weight, could predispose to impaired lung development.

Postnatal Infections and Immunology Affecting Chronic Lung Disease of Prematurity

Premature infants suffer significant respiratory morbidity during infancy with long-term negative consequences on health, quality of life, and health care costs. Enhanced susceptibility to a variety of infections and inflammation play a large role in early and prolonged lung disease following premature birth, although the mechanisms of susceptibility and immune dysregulation are active areas of research. This article reviews aspects of host-pathogen interactions and immune responses that are altered by preterm birth and that impact chronic respiratory morbidity in these children.

Maternal/neonatal vitamin D deficiency: a risk factor for bronchopulmonary dysplasia in preterms?

OBJECTIVE

The objective of this study was to investigate the possible association between maternal/neonatal 25-hydroxy vitamin D (25-OHD) levels and development of bronchopulmonary dysplasia.

STUDY DESIGN

One hundred and thirty-two preterm infants ⩽32 weeks of gestation who were diagnosed with respiratory distress syndrome were enrolled. 25-OHD levels were determined in maternal/neonatal blood samples that were obtained at the time of admission to the neonatal intensive care unit.

RESULT

A total of 100 infants were included and 31 (31%) developed bronchopulmonary dysplasia (BPD). Both maternal and neonatal 25-OHD levels in the BPD group were significantly lower compared with those in the no-BPD group (P=0.0001). A positive correlation was detected between maternal and neonatal 25-OHD levels. All of the infants with BPD had a 25-OHD level <10 ng ml(-1), which represented severe deficiency. Univariate logistic regression analysis revealed that maternal/neonatal vitamin D levels were a significant predictor of BPD (odds ratio (OR): 0.76 and 0.61, respectively, P<0.001).

CONCLUSION

We demonstrated for the first time that lower maternal and neonatal vitamin 25-OHD levels were associated with BPD development in preterm infants. However, further studies with larger sample sizes are needed to delineate the possible link between vitamin D deficiency and BPD.

Pre-eclampsia has an adverse impact on maternal and fetal health

Pre-eclampsia (preE) is a multifaceted complication found uniquely in the pregnant patient and one that has puzzled scientists for years. PreE is not a single disorder, but a complex syndrome that is produced by various pathophysiological triggers and mechanisms affecting about 5% of obstetrical patients. PreE is a major cause of premature delivery and maternal and fetal morbidity and mortality. PreE is characterized by de novo development of hypertension and proteinuria after 20 weeks of gestation and affects nearly every organ system, with the most severe consequences being eclampsia, pulmonary edema, intrauterine growth restriction, and thrombocytopenia. PreE alters the intrauterine environment by modulating the pattern of hormonal signals and activating the detrimental cellular signaling that has been transported to the fetus. The fetus has to adapt to this intrauterine environment with detrimental signals. The adaptive changes increase the risk of disease later in life. This review defines the predisposition and causes of preE and the cellular signaling detrimental to maternal health during preE. Moreover, the risk factors for diseases that are transmitted to the offspring have been addressed in this review. The detrimental signaling molecules that have been overexpressed in preE patients raises the possibility that those signals could be therapeutically blocked one day.

Influence of maternal pre-eclampsia on VEGF/PlGF heterodimer levels in preterm infants

OBJECTIVE

To measure VEGF/PlGF heterodimer levels in preterm infants born to mothers with preeclampsia.

METHODS

Neonates with birth weight <2000 g and gestational age ≤34 weeks were divided into two groups: born to mothers with Preeclampsia (PE) and controls. Neonates transferred from outside after the 72nd hour of life, death before blood collection, major congenital malformations or inborn errors of metabolism, and mothers with multiple pregnancies, STORCH complex infections, HIV or autoimmune conditions were excluded. Blood was collected within 72 h of birth and again at 28 days. VEGF/PlGF heterodimer levels were measured by ELISA.

RESULTS

We included 73 neonates (24 born to mothers with PE and 49 without PE). Mean gestational age was 30.32 ± 2.88 weeks and mean birth weight was 1288.62 ± 462.22 g. Median VEGF/PlGF levels were significantly higher in infants born to mothers with PE. VEGF/PlGF levels were inversely proportional to birth weight. There were no between-group differences in blood samples collected at age 28 days.

CONCLUSION

Higher VEGF/PlGF levels were higher in neonates exposed to PE, and there was a significant negative correlation between birth weight and VEGF/PlGF levels. Further studies to elucidate the role of this substance in the fetal and neonatal period are needed.

Associations of adherence to the New Nordic Diet with risk of preeclampsia and preterm delivery in the Norwegian Mother and Child Cohort Study (MoBa)

Preeclampsia and preterm delivery are serious complications of pregnancy and leading causes of perinatal mortality and morbidity worldwide. Dietary factors might be associated with these adverse outcomes. We investigated whether adherence to the New Nordic Diet (NND) was associated with preeclampsia and preterm delivery risks in the Norwegian Mother and Child Cohort Study (MoBa). Participants were recruited from all over Norway during the period 1999-2008. A previously constructed diet score assessing meal frequency, and the consumption of Nordic fruits, root vegetables, cabbages, potatoes, oatmeal porridge, whole grains, wild fish, game, berries, milk and water, was used to assess NND adherence. Associations between NND adherence and the outcomes were estimated in adjusted multivariate logistic regression models. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated. A total of 72,072 women was included in the study. High versus low NND adherence was associated with lower risk of total preeclampsia (OR 0.86; 95 % CI 0.78-0.95) and early preeclampsia (OR 0.71; 95 % CI 0.52-0.96). High compared with low NND adherence was associated with a lower risk of spontaneous preterm delivery among nulliparous women (OR 0.77; 95 % CI 0.66-0.89), whereas multiparous women with high NND adherence had a marginally significant higher risk of preterm delivery (OR 1.24; 95 % CI 1.00-1.53). High NND adherence was associated with a lower relative risk of preeclampsia and of spontaneous preterm delivery among nulliparous women; however, among multiparous women there was a higher relative risk of preterm delivery.

Prenatal inflammatory risk factors for development of bronchopulmonary dysplasia

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a serious, chronic lung disease affecting preterm infants.

OBJECTIVE

To identify prenatal risk factors for BPD, focusing on inflammation.

METHODS

Observational cohort study including 106,339 preterm infants, live born before gestational week 37 + 0, from 1988 to 2009 in Sweden. A total of 2,115 infants were diagnosed with BPD, of which 1,393 were born extremely preterm, before gestational week 28 + 0. Information on risk factors was obtained from national health registers and included maternal chronic inflammatory diseases, pregnancy related diseases, and drugs related to treatment of inflammation or infection during pregnancy. Adjusted odds ratios (OR) were calculated in multivariable logistic regression models and are presented with 95% confidence intervals [95% CI].

RESULTS

Preeclampsia was the strongest risk factor for BPD [adjusted OR 2.04, 95% CI 1.83, 2.29]. For extremely preterm infants the adjusted OR was 1.33 [95% CI 1.08, 1.64]. Chorioamnionitis was associated with an increased risk of BPD, but only when including all infants in the analyses [OR 1.33, 95% CI 1.19, 1.48]. No apparent associations were found between maternal chronic inflammatory disease or use of anti-inflammatory drugs and the risk of BPD. Maternal diabetes mellitus, gestational diabetes and maternal use of antibiotics were associated with reduced risks of BPD.

CONCLUSION

Preeclampsia related disorders increased the risk and maternal diabetes mellitus and gestational diabetes reduced the risk for BPD. As angiogenic factors play a role in preeclampsia and diabetes our findings suggest that an impaired angiogenesis may contribute to BPD development.

Placental pathologic changes of maternal vascular underperfusion in bronchopulmonary dysplasia and pulmonary hypertension

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease of infancy, and BPD-associated pulmonary hypertension (PH) is a serious complication that can negatively impact later childhood health. There is growing evidence that lung injury leading to BPD and PH is due to chronic fetal hypoxia-ischemia. The purpose of this study was to investigate whether placental pathologic changes of maternal vascular underperfusion (MVU) are associated with BPD, and further increased with PH.

METHODS

We conducted a 5-year retrospective cohort study of premature infants born ≤28 weeks. BPD was defined as persistent oxygen requirement at 36 weeks corrected gestational age. PH was identified using a standardized algorithm of echocardiogram review. Archived placental slides underwent standardized masked histopathologic review. Logistic regression modeling was performed, taking into account important maternal and infant covariates.

RESULTS

Among 283 births, 121 had MVU, of which 67 (55%) developed BPD, and 24 (20%) had PH. Among the common neonatal complications of extreme prematurity, BPD was the only outcome that was increased with MVU (P < 0.001). After adjustment for birth weight, fetal growth restriction, preeclampsia and other factors, infants with MVU were more likely to develop BPD (adjusted odds ratio = 2.6; 95% confidence interval = 1.4, 4.8). Certain MVU sublesions (fibrinoid necrosis/acute atherosis and distal villous hypoplasia/small terminal villi) were increased with PH (P < 0.001).

DISCUSSION

Placental MVU may identify BPD infants who were exposed to intrauterine hypoxia-ischemia, which increases their risk for development of PH disease.

CONCLUSIONS

Our findings have important implications for providing earlier and more effective therapies for BPD.

The association between hypertensive disorders in pregnancy and bronchopulmonary dysplasia: a systematic review

BACKGROUND

Whether hypertensive disorders in pregnancy (HDP) are the risk factors of bronchopulmonary dysplasia (BPD) is controversial. A systematic review was made to determine the association between HDP and BPD in preterm infants.

METHODS

We searched PubMed, Embase, Cochrane Library, ScienceDirect, Web of Science, with no language limitation, and reviewed the reference lists of the selected articles to identify additional relevant publications and contacted the authors of relevant studies for further information. The data were extracted independently by 2 reviewers who used a predetermined data extraction form. Studies were combined with an odds ratio (OR) using a random-effects model. Meta-regression and subgroup analysis were used to explore potential confounders. Funnel plots, Egger's test and Begg's test were used to investigate the publication bias. The Trim and Fill method was used to control the publication bias.

RESULTS

A total of 787 studies were identified and only 15 studies (20 779 patients) were included. The pooled unadjusted OR showed that HDP was significantly associated with BPD (P=0.04; OR=1.29, 95% CI=1.01-1.65). Heterogeneity was substantial (I(2)=74%) and might be partially explained by different variables in maternal complications between the control groups across the studies. The pooled adjusted OR suggested the same conclusion that HDP was a risk factor for BPD (P=0.01; OR=1.59, 95% CI=1.11-2.26). Funnel plot and Egger's test showed that there were publication bias of unadjusted estimate of association between HDP and BPD.

CONCLUSIONS

Unadjusted analyses showed that the rate of BPD was slightly higher in the infants exposed to HDP, and adjusted analyses confirmed this finding. But this result should be interpreted cautiously because substantial heterogeneity and publication bias were identified in this review.

Preeclampsia is a biomarker for vascular disease in both mother and child: the need for a medical alert system

This paper reviews the literature pertaining to the impact of preeclampsia not only on the mother but particularly on the children. The review points to the higher blood pressure in children born to preeclamptic mothers compared to controls, their increased tendency to suffer strokes, the reduction in their cognitive ability, and their vulnerability to depression. Mechanisms that may induce these changes are emphasized, particularly the placental vascular insufficiency and the resulting hypoxic and proinflammatory environments in which the fetus develops. The hypothesis proposed is that these changes in the fetal-placental environment result in epigenetic programming of the child towards a higher propensity for vascular disease. The review's main recommendation is that, within ethical boundaries, the medical records of individuals born to preeclamptic mothers should clearly indicate this event and should be made available to the affected individuals so that preventive measures against vascular complications and lifestyle changes that may mitigate the latter can be instituted.