Preeclampsia Associates with Asthma, Allergy, and Eczema in Childhood

Association between hypertensive disorders of pregnancy and gestational diabetes and risk of atopic dermatitis in childhood: A systematic review and meta-analysis

The purpose of this review was to examine if maternal hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM) result in an increased risk of atopic dermatitis or eczema (AD-E) in childhood. We searched the databases of PubMed, Embase, CENTRAL, Web of Science, and Scopus for cohort or case-control studies up to 25th June 2023. Random-effects meta-analysis was done to generate the odds ratio (OR) of the association between HDP/GDM and AD-E. Eight studies were included. Meta-analysis of five studies showed that GDM in the mother was associated with an increased risk of AD-E in the offspring (OR: 1.35 95% CI: 1.13, 1.61 I2 = 61%). Pooled analysis of four studies demonstrated no association between HDP and risk of AD-E in the offspring (OR: 1.03 95% CI: 0.99, 1.08 I2 = 0%). The results did not change on sensitivity analysis and subgroup analysis based on study type, method of AD-E diagnosis, and sample size. This meta-analysis suggests that GDM may significantly increase the risk of AD-E in childhood, however, HDP does not seem to impact the risk of AD-E. Evidence is limited by the small number of studies and high interstudy heterogeneity. Further studies are needed to improve the quality of evidence.

Pregestational maternal risk factors for preterm and term preeclampsia: A population-based cohort study

INTRODUCTION

Most studies on factors affecting the risk of preeclampsia have not separated preterm from term preeclampsia, and we still know little about whether the predisposing conditions have a differentiated effect on the risk of preterm and term preeclampsia. Our aim was to assess whether diabetes type 1 and 2, chronic kidney disease, asthma, epilepsy, rheumatoid arthritis and chronic hypertension were differentially associated with preterm and term preeclampsia.

MATERIAL AND METHODS

This is a nationwide, population-based cohort study containing all births registered in the Medical Birth Registry of Norway from 1999 to 2016. Multinomial logistic regression analysis was used to estimate relative risk ratios (RRRs) with 95% confidence intervals (95% CIs), adjusting for maternal age, parity, multiple gestation and all other studied maternal risk factors.

RESULTS

We registered 1 044 860 deliveries, of which 9533 (0.9%) women had preterm preeclampsia (<37 weeks) and 26 504 (2.5%) women had term preeclampsia (>37 weeks). Most of the assessed maternal risk factors were associated with increased risk for both preterm and term preeclampsia, with adjusted RRRs ranging from 1.2 to 10.5 (preterm vs no preeclampsia) and 0.9-5.7 (term vs no preeclampsia). Diabetes type 1 and 2 (RRR preterm vs term preeclampsia 2.89, 95% CI 2.46-3.39 and RRR 1.68, 95% CI 1.25-2.25, respectively), chronic kidney disease (RRR 1.55, 95% CI 1.11-2.17) and chronic hypertension (RRR 1.85, 95% CI 1.63-2.10) were more strongly associated with preterm than term preeclampsia in adjusted analyses. For asthma, epilepsy and rheumatoid arthritis, RRRs were closer to one and not significant when comparing risk of preterm and term preeclampsia. Main results were similar when using a diagnosis at <34 weeks to define preterm preeclampsia.

CONCLUSIONS

Diabetes type 1 and 2, chronic kidney disease and chronic hypertension were more strongly associated with preterm than term preeclampsia.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Birth mode is associated with development of atopic dermatitis in infancy and early childhood

Background

Birth by caesarean section (CS) is associated with development of allergic diseases, but its role in the development of atopic dermatitis (AD) is less convincing.

Objective

Our primary aim was to determine if birth mode was associated with AD in 3-year-olds and secondarily to determine if birth mode was associated with early onset and/or persistent AD in the first 3 years of life.

Methods

We included 2129 mother-child pairs from the Scandinavian population-based prospective PreventADALL cohort with information on birth mode including vaginal birth, either traditional (81.3%) or in water (4.0%), and CS before (6.3%) and after (8.5%) onset of labor. We defined early onset AD as eczema at 3 months and AD diagnosis by 3 years of age. Persistent AD was defined as eczema both in the first year and at 3 years of age, together with an AD diagnosis by 3 years of age.

Results

AD was diagnosed at 3, 6, 12, 24, and/or 36 months in 531 children (25%). Compared to vaginal delivery, CS was overall associated with increased odds of AD by 3 years of age, with adjusted odds ratio (95% confidence interval) of 1.33 (1.02-1.74), and higher odds of early onset AD (1.63, 1.06-2.48). The highest odds for early onset AD were observed in infants born by CS after onset of labor (1.83, 1.09-3.07). Birth mode was not associated with persistent AD.

Conclusion

CS was associated with increased odds of AD by 3 years of age, particularly in infants presenting with eczema at 3 months of age.

25 Years of translational research in the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC)

The Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) mother-child cohorts have provided a foundation of 25 years of research on the origins, prevention, and natural history of childhood asthma and related disorders. COPSAC's approach is characterized by clinical translational research with longitudinal deep phenotyping and exposure assessments from pregnancy, in combination with multi-omic data layers and embedded randomized controlled trials. One trial showed that fish oil supplementation during pregnancy prevented childhood asthma and identified pregnant women with the highest benefits from supplementation, thereby creating the potential for personalized prevention. COPSAC revealed that airway colonization with pathogenic bacteria in early life is associated with an increased risk of asthma. Further, airway bacteria were shown to be a trigger of acute asthma-like symptoms, with benefit from antibiotic treatment. COPSAC identified an immature gut microbiome in early life as a risk factor for asthma and allergy and further demonstrated that asthma can be predicted by infant lung function. At a molecular level, COPSAC has identified novel susceptibility genes, early immune deviations, and metabolomic alterations associated with childhood asthma. Thus, the COPSAC research program has enhanced our understanding of the processes causing childhood asthma and has suggested means of personalized prevention and treatment.

The association between hypertensive disorders of pregnancy and childhood asthma

BACKGROUND

Asthma is a chronic long-term inflammatory disease of the airways and is a major global health challenge. The primary aim of this study was to investigate the association between hypertensive disorders of pregnancy (HDP) and the risk of asthma at or before the age of seven years using the UK Millennium Cohort Study (MCS).

METHODS

Overall, 18,552 families were recruited for wave one of the MCS when the child was 9 months old, and subsequently participated in waves two, three and four when they were three, five and seven years respectively. HDP were self-reported by mothers in wave one. The primary outcome was a parent-reported diagnosis of "ever asthma" at seven years, based on responses to a validated questionnaire.

RESULTS

Following adjustment for a range of potential confounding factors, HDP was found to be associated with asthma in the offspring (adjusted odds ratio (AOR 1.35; 95% CI: 1.15-1.59)). A larger effect estimate was observed amongst children exposed to HDP and born preterm (AOR 1.81; 95% CI: 1.25-2.61) or small for gestational age (SGA) (AOR = 1.58; (95% CI: 1.15-2.18)).

CONCLUSIONS

In conclusion, children exposed to HDP may be at increased odds of asthma diagnosis by age seven, particularly if they were born preterm or SGA.

IMPACT

There is a paucity of data investigating the relationship between hypertensive disorders of pregnancy and childhood asthma, with recent studies showing conflicting results. Our study investigated this relationship using a large cohort with ample information on a wide range of confounding factors. Our study showed that individuals exposed to HDP may be at increased odds of asthma diagnosis by age seven years, particularly if they were also born SGA or preterm.

Forced expiratory flows and diffusion capacity in infants born from mothers with pre-eclampsia

RATIONALE

Animal models suggest pre-eclampsia (Pre-E) affects alveolar development, but data from humans are lacking.

OBJECTIVE

Assess the impact of Pre-E on airway function, diffusion capacity, and respiratory morbidity in preterm and term infants born from mothers with Pre-E.

METHODS

Infants born from mothers with and without Pre-E were recruited for this study; term and preterm infants were included in both cohorts. Respiratory morbidity in the first 12 months of life was assessed through monthly phone surveys. Raised volume rapid thoracoabdominal compression and measurement of diffusion capacity of the lung to carbon monoxide (DLCO) were performed at 6 months corrected age.

MEASUREMENTS AND MAIN RESULTS

There were 146 infants in the Pre-E cohort and 143 in the control cohort. The Pre-E cohort was further divided into nonsevere (N = 41) and severe (N = 105) groups. There was no significant difference in DLCO and DLCO/alveolar volume among the three groups. Forced vital capacity was similar among the three groups, but the nonsevere Pre-E group had significantly higher forced expiratory flows than the other two groups. After adjusting for multiple covariates including prematurity, the severe Pre-E group had a lower risk for wheezing in the first year of life compared to the other two groups.

CONCLUSIONS

Pre-E is not associated with reduced DLCO, lower forced expiratory flows, or increased wheezing in the first year of life. These results differ from animal models and highlight the complex relationships between Pre-E and lung function and respiratory morbidity in human infants.

Increased risk of early-onset childhood systemic lupus erythematosus for children born to affected parents: A nationwide child-parent cohort study

Objective

Children of women with systemic lupus erythematosus (SLE) are at risk for childhood-onset SLE (cSLE). This study evaluated the incidence of early-onset cSLE and associated risk factors, including concomitant maternal and paternal autoimmune diseases, for these children.

Methods

A population-based cohort study was conducted using national databases including the linked information of children and parents. Children of women with SLE and those of women without SLE were identified between 2004 and 2015. The cumulative cSLE incidence was estimated using the Kaplan-Meier method. The marginal Cox model was used to calculate the hazard ratio (HR) for cSLE events.

Results

A total of 4,419 singletons of women with SLE and 1,996,759 singletons of women without SLE were identified. There were 9 (0.20%) and 503 (0.03%) incident cases of early-onset cSLE for offspring of women with and without SLE, respectively (incidence rate ratio, 8.34; 95% confidence interval [CI], 3.79–15.95]. The adjusted HR of incident cSLE in children of women with SLE was 4.65 (95% CI 2.11–10.24). Other risks for cSLE included pregnancy-induced hypertension/preeclampsia/eclampsia, paternal SLE, paternal Sjögren’s syndrome (SS), and maternal SS.

Conclusions

This national child-parent cohort study demonstrated that children of women with SLE are at significantly higher risk for cSLE during early childhood. Moreover, paternal SLE and parental SS increase the risk of cSLE for offspring.

A review of infant growth and psychomotor developmental outcomes after intrauterine exposure to preeclampsia

Preeclampsia is a hypertensive disorder of pregnancy with serious health implications for mother and their offspring. The uteroplacental vascular insufficiency caused by preeclampsia is associated with epigenetic and pathological changes in the mother and fetus. However, the impact of preeclampsia in infancy (birth to 2 years), a time of rapid development influenced by pre- and postnatal factors that can predict future health outcomes, remains inconclusive. This narrative review of 23 epidemiological and basic science studies assessed the measurement and impact of preeclampsia exposure on infant growth and psychomotor developmental outcomes from birth to 2 years. Studies assessing infant growth report that preeclampsia-exposed infants have lower weight, length and BMI at 2 years than their normotensive controls, or that they instead experience accelerated weight gain to catch up in growth by 2 years, which may have long-term implications for their cardiometabolic health. In contrast, clear discrepancies remain as to whether preeclampsia exposure impairs infant motor and cognitive development, or instead has no impact. It is additionally unknown whether any impacts of preeclampsia are independent of confounders including shared genetic factors that predispose to both preeclampsia and childhood morbidity, perinatal factors including small for gestational age or preterm birth and their sequelae, and postnatal environmental factors such childhood nutrition. Further research is required to account for these variables in larger cohorts born at term, to help elucidate the independent pathophysiological impact of this clinically heterogenous and dangerous disease.

Microbial Dysbiosis Tunes the Immune Response Towards Allergic Disease Outcomes

The hygiene hypothesis has been popularized as an explanation for the rapid increase in allergic disease observed over the past 50 years. Subsequent epidemiological studies have described the protective effects that in utero and early life exposures to an environment high in microbial diversity have in conferring protective benefits against the development of allergic diseases. The rapid advancement in next generation sequencing technology has allowed for analysis of the diverse nature of microbial communities present in the barrier organs and a determination of their role in the induction of allergic disease. Here, we discuss the recent literature describing how colonization of barrier organs during early life by the microbiota influences the development of the adaptive immune system. In parallel, mechanistic studies have delivered insight into the pathogenesis of disease, by demonstrating the comparative effects of protective T regulatory (Treg) cells, with inflammatory T helper 2 (Th2) cells in the development of immune tolerance or induction of an allergic response. More recently, a significant advancement in our understanding into how interactions between the adaptive immune system and microbially derived factors play a central role in the development of allergic disease has emerged. Providing a deeper understanding of the symbiotic relationship between our microbiome and immune system, which explains key observations made by the hygiene hypothesis. By studying how perturbations that drive dysbiosis of the microbiome can cause allergic disease, we stand to benefit by delineating the protective versus pathogenic aspects of human interactions with our microbial companions, allowing us to better harness the use of microbial agents in the design of novel prophylactic and therapeutic strategies.

The impact of the gut microbiota on T cell ontogeny in the thymus

The intestinal microbiota is critical for the development of gut-associated lymphoid tissues, including Peyer's patches and mesenteric lymph nodes, and is instrumental in educating the local as well as systemic immune system. In addition, it also impacts the development and function of peripheral organs, such as liver, lung, and the brain, in health and disease. However, whether and how the intestinal microbiota has an impact on T cell ontogeny in the hymus remains largely unclear. Recently, the impact of molecules and metabolites derived from the intestinal microbiota on T cell ontogeny in the thymus has been investigated in more detail. In this review, we will discuss the recent findings in the emerging field of the gut-thymus axis and we will highlight the current questions and challenges in the field.

Pre-eclampsia and risk of early-childhood asthma: a register study with sibling comparison and an exploration of intermediate variables

BACKGROUND

We aimed to study whether pre-eclampsia is associated with childhood asthma, allergic and non-allergic asthma, accounting for family factors and intermediate variables.

METHODS

The study population comprised 779 711 children born in 2005-2012, identified from Swedish national health registers (n = 14 823/7410 exposed to mild/moderate and severe pre-eclampsia, respectively). We used Cox regression to estimate the associations of mild/moderate and severe pre-eclampsia with incident asthma, before and after age 2 years. Cox regressions were controlled for familial factors using sibling comparisons, then stratified on high and low risk for intermediate variables: caesarean section, prematurity and small for gestational age. We used logistic regression for allergic and non-allergic prevalent asthma at 6 years as a measure of more established asthma.

RESULTS

The incidence of asthma in children was 7.7% (n = 60 239). The associations varied from adjusted hazard ratio (adjHR) 1.11, 95% confidence interval (CI): 1.00, 1.24 for mild/moderate pre-eclampsia and asthma at >2 years age, to adjHR 1.78, 95% CI: 1.64, 1.95 for severe pre-eclampsia and asthma at <2 years age. Sibling comparisons attenuated most estimates except for the association between severe pre-eclampsia and asthma at <2 years age (adjHR 1.45, 95% CI: 1.10, 1.90), which also remained when stratifying for the risk of intermediates. Mild/moderate and severe pre-eclampsia were associated with prevalent non-allergic (but not allergic) asthma at 6 years, with adjusted odds ratio (adjOR) 1.17, 95% CI: 1.00, 1.36 and adjOR 1.51, 95% CI: 1.23, 1.84, respectively.

CONCLUSIONS

We found evidence that severe, but not mild/moderate, pre-eclampsia is associated with asthma regardless of familial factors and confounders.

Early Sensory and Temperament Features in Infants Born to Mothers With Asthma: A Cross-Sectional Study

Maternal asthma in pregnancy is associated with an increased risk of adverse perinatal outcomes. Adverse perinatal outcomes may result in poorer infant developmental outcomes, such as temperament and sensory difficulties. This study aimed to (1) assess differences in temperament and sensory features between infants born to mothers with and without asthma and (2) investigate differences in these infant behaviours as a function of maternal asthma severity and asthma control. Mothers completed the Carey Temperament Scales and the Sensory Profile 2 at either 6 weeks, 6 months, or 12 months postpartum. Overall, we observed no significant differences between infants born to mothers with and without asthma in their temperament or sensory features; scores in both domains fell within the normative range. More infants in the asthma group, however, were reported to be highly distractible. When compared with normative data, infants in both groups were reported to have poor predictability of biological functions and fewer infants engaged in low levels of sensory behaviours. Some infants were observed to experience difficulties with hyper-reactivity within several domains. Maternal asthma severity and control during pregnancy were not linked to significant differences between infant temperament and sensory features. The present findings indicate that infants born to mothers with asthma are not at an increased risk overall for temperament or sensory difficulties, compared to control infants. However, a subset of infants across both groups may be at risk for attention or sensory hyper-reactivity difficulties. Further research into the developmental outcomes of infants born to mothers with asthma is warranted.

Hypertensive disorders of pregnancy and risk of allergic conditions in children: Findings from the Japan Environment and Children's study (JECS)

Background

Hypertensive disorders of pregnancy (HDP) are one of the most common medical conditions that women encounter during pregnancy. Whether or not hypertensive disorders of pregnancy (HDP) are associated with allergic conditions in the offspring is unclear. This study used data from a large Japanese birth cohort to investigate whether HDP contributes to the development of allergic conditions in the offspring at 3 years. We also assessed the effect of blood pressure at different pregnancy trimesters on children's allergies.

Methods

We obtained data from the Japan Environment and Children's Study (JECS), which included 104 062 fetal records. After data selection, we analyzed 77 505 mother-child pairs, using logistic regression models to examine the relationships between HDP or the mother's blood pressure and their children's allergic conditions. In addition, we also evaluated the effect of HDP during pregnancy on allergies with a propensity score matched dataset, using a logistic regression model that predicts the conditional probability of whether a mother belonged to the HDP or non-HDP group.

Results

Among the 77 505 mothers eligible for analysis, 2334 (3.0%) had HDP. Percentages of women with hypertension were 1.7% in early gestation, 1.0% in mid-gestation, and 1.6% in late gestation. After adjusting for multiple potential confounders, HDP contributed nothing to allergy development in offspring. Children born to women with hypertension were no more likely than those without to have allergic conditions at 3 years of age. The propensity score matched dataset showed similar findings.

Conclusion

HDP and high blood pressure during pregnancy are apparently not risk factors for developing allergy in offspring. This information may help clinicians in counseling women who suffered HDP during pregnancy.

Association of KIR Genes and MHC Class I Ligands with Atopic Dermatitis

Atopic dermatitis (AD) is a chronic illness that is associated with immune dysregulation. NK cell function has previously been associated with AD. NK cells directly interact with polymorphic HLA class I ligand variants using killer cell Ig-like receptors (KIRs). The purpose of this study was to identify potential associations between NK cell function and AD by evaluating variation in the presence of KIR genes as well as KIR gene interactions with the appropriate HLA class I KIR-specific ligands. Human DNA from the genetics of AD case-control study was used to genotype HLA class I KIR-specific ligands and the presence of KIR genes. In the full cohort, an increased risk of AD was noted for KIR2DL5 (1.51 [1.13, 2.01]), KIR2DS5 (1.72 [1.26, 2.34]), and KIR2DS1 (1.41 [1.04, 1.91]). Individuals with KIR2DS5 or KIR2DS1 and the HLA-C*C2 epitope were at an increased risk of AD (1.74 [1.21, 2.51] and 1.48 [1.04, 2.12], respectively). The HLA-B*-21T (TT) leader sequence increased the risk of AD across ethnicity. African Americans with KIR2DL2, KIR2DS1, KIR2DL5, and KIR2DS5 are more likely to have AD, and the risk increased for KIR2DS1 and KIR2DS5 in the presence of appropriate HLA-C C2 epitope. The risk of AD also increased for individuals with the HLA-B*-21T leader sequence. Future studies should focus on KIR gene allelic variation as well as consider cell-based measurements of KIR and the associated HLA class I epitopes.

Hypertensive disorders in pregnancy and risk of asthma in offspring: a systematic review and meta-analysis

OBJECTIVES

The association between hypertensive disorders in pregnancy (HDP) and an increased risk of asthma in offspring remains controversial. No systematic review of this topic has been performed. The aim of this systematic review was to summarise the available evidence regarding the association between HDP and the risk of asthma in offspring.

DESIGN

Systematic review and meta-analysis.

METHODS

On the basis of a prepared protocol, a systematic search of PubMed, EMBASE, the Cochrane Library and Web of Science was performed using a detailed search strategy from the database inception to 17 January 2020. Cohort, case-control and cross-sectional studies published in English reporting the diagnoses of maternal HDP and asthma in offspring were included. The Meta-analysis of Observational Studies in Epidemiology guidelines were followed throughout the study. The estimated pooled ORs of HDP and asthma in offspring were calculated from the studies, and the meta-analysis was performed using random-effects models.

RESULTS

Ten cohort studies involving a total of 6 270 430 participants were included. According to the Newcastle-Ottawa Scale, the overall methodological quality was good since 8 studies were of high quality and 2 studies were of moderate quality. After controlling for potential confounders, HDP was associated with a possible increased risk of asthma in offspring, with a pooled adjusted OR (aOR) of 1.19 (95% CI 1.12 to 1.26). The subgroup analyses according to HDP subgroups, sibling design, study quality, study location, offspring ages, singleton status, exposure assessment, outcome assessment and adjusted factors showed similar results.

CONCLUSIONS

Exposure to HDP may be associated with an increased risk of asthma in offspring. Further research is needed to verify the results and determine whether the observed relationship is causal.

PROSPERO REGISTRATION NUMBER

CRD42020148250.

Maternal tobacco exposure during pregnancy and allergic rhinitis in offspring: A systematic review and meta-analysis

BACKGROUND

Maternal tobacco exposure during pregnancy is known to cause a potential hazard to the offspring's health. So far, published studies have shown no consistent results with whether tobacco exposure in utero is causally linked to the development of allergic rhinitis in offspring. The aim of this study was to comprehensively evaluate the association between maternal tobacco exposure during pregnancy and allergic rhinitis in offspring by meta-analysis and to provide reference for clinical work.

METHODS

Literatures were searched in CNKI, Wanfang Data, VIP, SinoMed, PubMed, Web of science and Embase up to September 30,2020. Screening, inclusion, quality assessment, data extraction and data analysis of the literatures were conducted. Meta-analysis was performed with Revman 5.3 and State15.1 software. Odds ratio (OR) and 95%CI were used as observation indicators.

RESULTS

We had retrieved 16 articles with 22 independent datasets and 11,49,879 sample size. When all the studies were analyzed together, the results showed that maternal smoking exposure during pregnancy would increase the risk of allergic rhinitis in offspring (OR = 1.13, 95%CI:1.02-1.26), especially maternal passive smoking during pregnancy (OR = 1.39, 95%CI:1.05-1.84). But subgroup analysis showed that maternal active smoking during pregnancy was only significantly associated with offspring allergic rhinitis in cross-sectional studies (OR = 1.24, 95%CI:1.07-1.45) and study done in America study (OR = 1.22, 95%CI:1.05-1.42).

CONCLUSIONS

Tobacco exposure during pregnancy could increase the risk of allergic rhinitis in offspring. The importance of avoiding prenatal tobacco exposure should be emphasized more for the health of next generation in the public.

Hypertensive Disorders of Pregnancy and Behavioural Outcomes in the Offspring: Findings from the Millennium Cohort Study

BACKGROUND

The aim of this study was to examine the association between hypertensive disorders of pregnancy (HDP) and behavioural outcomes in offspring at five time-points.

METHODS

We used maternal-reported data from the Millennium Cohort Study. Data on HDP were collected when children were 9-months. Data on behavioural outcomes were collected at age 3, 5, 7, 11 and 14years using the Strengths and Difficulties Questionnaire (SDQ). Multivariate logistic regression analysis examined a HDP-behavioural difficulties relationship, using validated SDQ cut-off points. Multilevel models with linear splines examined the association between HDP and repeated measures of SDQ.

RESULTS

18,274 singleton children were included in the study at baseline, Multivariate logistic regression suggested HDP was not significantly associated with SDQ domain cut-off points at ages 3, 7 and 11years. At age 5years, HDP was associated with a 40% increased odds of behavioural difficulties based on total SDQ(≥17) (OR:1.40, 95% CI:1.03,1.91). HDP was associated with a 43% increased odds of Peer Problem difficulties at age 5 (OR:1.43, 95% CI:1.10,1.86), and a 28% increased odds of Peer Problem difficulties(≥4) at age 14 (OR:1.28, 95% CI:1.02,1.61). In the linear spline model, mean SDQ score was higher at each time-point in those exposed to HDP, although did not always reach statistical significance.

LIMITATIONS

Data on different classifications of HDP were unavailable; therefore, we could not examine the effect of gestational hypertension and preeclampsia separately.

CONCLUSIONS

While we did not find strong evidence of associations between HDP and behavioural outcomes overall, some associations between HDP and behavioural difficulties did persist at age 5 and 14years.

Gestational hypertension and childhood atopy: a Millennium Cohort Study analysis

Gestational hypertension may confer risk of atopic disease in offspring through a direct biological mechanism, but another possibility is that risk is mediated through complications of pregnancy. To explore these associations, we conducted an analysis of a nationally representative birth cohort based in the UK involving children born 2000-2002. We included 12,450 mother-child pairs. We used logistic regression to estimate the association between hypertensive disease and asthma, hay fever, or eczema by age 5, and parentally reported early wheeze and severe wheeze. Mediation by gestation at delivery and caesarean delivery was explored using causal mediation analysis. Odds ratios (95% CI) for gestational hypertension and childhood asthma, hay fever, and eczema were 1.32 (1.09, 1.59), 1.22 (0.97, 1.55), and 1.12 (0.96, 1.32) respectively, adjusted for confounding. The population attributable fractions were 2.4% (1.0-3.8%), 0.9% (-0.3% to 2.1%), and 1.8% (0.0-3.7%), respectively. Accounting for mediation by gestational age and caesarean delivery, odds ratios (95% CI) for the potential direct effects of gestational hypertension were 1.21 (0.97, 1.50), 1.17 (0.91, 1.49), and 1.11 (0.94, 1.31) for the same.Conclusion: Gestational hypertension was weakly positively associated with asthma and this was partly mediated by earlier delivery. Only a small proportion of early childhood asthma was attributable to gestational hypertensive disease in this representative UK-based birth cohort. What is known: • Gestational hypertension has been shown to be an inconsistent risk factor for the atopic diseases. • The in utero immune environment may modify the risk of atopy in offspring; alternatively, complications of pregnancy including caesarean delivery and prematurity may explain an association between hypertensive disease and atopy. What is new: • Self-reported gestational hypertension was a weak risk factor for asthma and wheeze in the Millennium Cohort Study. • Part of the association between gestational hypertensive disease and asthma was explained by earlier delivery.

Association between hypertensive disorders of pregnancy and the risk of asthma, eczema and allergies in offspring: A systematic review and meta-analysis

OBJECTIVE

Conduct a systematic review and meta-analysis examining the association between hypertensive disorders of pregnancy (HDP) and risk of asthma, eczema, food allergies and allergic rhinitis in the offspring.

DESIGN

A systematic review and random-effects meta-analyses were used to synthesize the published literature. PRISMA guidelines were followed throughout. Two independent reviewers carried out data extraction and quality assessment of included studies. Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess certainty of findings.

DATA SOURCES

A systematic search of PubMed, Embase, Web of Science and CINAHL was performed from inception of databases-21 April 2020, supplemented by hand-searching reference lists of included articles.

ELIGIBILITY CRITERIA

Two reviewers independently reviewed titles, abstracts and full-text articles. English language, cohort, case-control and cross-sectional published studies examining the association between HDP (primary exposure: pre-eclampsia; secondary exposures: all other HDP) and asthma, eczema, food allergies and allergic rhinitis were included.

RESULTS

Of the 2833 studies retrieved, 14 studies met inclusion criteria. Of these, 11 studies reported evidence of association between HDP and atopic disorders. Thirteen studies reported estimates for asthma. Seven of these included adjusted estimates (including 3 645 773 participants) for a pre-eclampsia-asthma relationship resulting in a pooled odds ratio (OR) of 1.14 (95% CI: 1.04, 1.26) (I²  = 62%). However, this OR was reduced to 1.08 (95% CI: (0.78, 1.48) when the large registry-based cohort studies were excluded, and only studies using parent-reported measures to determine a diagnosis of asthma were included. Four studies included adjusted estimates (including 254 998 participants) for other HDP and asthma (pooled OR: 1.02, 95% CI: 0.96, 1.09) (I²  = 0%). Two studies provided adjusted estimates (including 1 699 663 participants) for a pre-eclampsia-eczema relationship (pooled OR: 1.06, 95% CI: 0.98, 1.14) (I²  = 0%). One study including pre-eclampsia-food allergies was identified (OR: 1.28, 95% CI: 1.11, 1.46). Three studies examined a HDP (including pre-eclampsia) and allergic rhinitis relationship, with effect estimates ranging from 1.14 to 2.10. Studies were classified as low or low-moderate risk of bias, while GRADE certainty of findings were low to very low.

CONCLUSIONS

While pre-eclampsia was associated with a possible increased risk of asthma in offspring, there was no evidence for a relationship between other HDP and asthma. There is a lack of published literature examining the association between HDP and eczema, food allergy and allergic rhinitis. Further primary research is warranted to gain a better understanding of the association between HDP and the risk of childhood atopic disease.

SYSTEMATIC REVIEW REGISTRATION

Review protocol in appendix.

Maternal known drug allergy and long-term dermatological morbidity of the offspring

Drug allergy is associated with adverse short-term perinatal outcomes such as caesarian delivery and preterm delivery. The aim of the present study was to determine whether being born to a mother with known drug allergy increases the risk for long-term dermatological morbidity of the offspring. A population-based cohort study, comparing long-term dermatological morbidity of offspring to mothers with and without known drug allergy, was conducted. Dermatological morbidity was assessed up to the age of 18 years according to a predefined set of ICD-9 codes associated with hospitalization of the offspring. A Kaplan-Meier survival curve was used to compare cumulative incidence of long-term dermatological morbidity, and a Cox proportional hazards model was constructed to control of confounders. During the study period, 243,682 deliveries met the inclusion criteria, of them 4% (n = 9756) were of mothers with known drug allergy. Offspring born to mothers with known drug allergy had higher rates of long-term dermatological morbidity Likewise, the cumulative incidence of long-term dermatological morbidity was higher as compared with those without known drug allergy (Kaplan-Meier log-rank P = .021). Using a Cox proportional hazards model, controlling for confounders, being born to a mother with known drug allergy was found to be an independent risk factor for long-term dermatological morbidity of the offspring (adjusted HR 1.2, 95% CI 1.03-1.33, P = .016). Being born to a mother with known drug allergy is independently associated with higher risk for long-term dermatological morbidity of the offspring.

Maternal history of recurrent pregnancy loss increases the risk for long-term pediatric respiratory morbidity of the offspring

BACKGROUND

While the etiology in many cases of recurrent pregnancy loss (RPL) is unclear, recent evidence suggests possible immunological dysfunction, which is also implicated in the pathophysiology of many pediatric respiratory diseases.

OBJECTIVE

We sought to investigate whether maternal history of RPL is associated with long-term respiratory morbidity of the offspring.

STUDY DESIGN

A population based cohort analysis was performed comparing the risk of long-term respiratory morbidity (up to the age of 18 years) of children born to mothers with and without a history of RPL (defined as two or more losses). Respiratory morbidity included hospitalizations involving a predefined set of ICD-9 codes, as recorded in the hospital medical records. Deliveries occurred between the years 1991 and 2014 in a tertiary medical center. A Kaplan-Meier survival curve was constructed to compare cumulative respiratory morbidity, and a Cox proportional hazards model was used to control for confounders.

RESULTS

During the study period, 242 187 newborns met the inclusion criteria; 5% (n = 12 182) of which were offspring to mothers with a history of RPL. Respiratory morbidity was significantly more common in the exposed group (6.0% vs 4.8%, P < .001). Specifically, offspring to mothers with a history of RPL had higher rates of obstructive sleep apnea and asthma (P < .05). The Kaplan-Meier survival curve exhibited a higher cumulative incidence of total respiratory morbidity in offspring of mothers with a history of RPL (Log rank P < .001). In the Cox regression, maternal history of RPL was independently associated with increased pediatric respiratory morbidity of the offspring with an adjusted hazard ratio of 1.24 (95 % confidence interval [95%CI], 1.15-1.34, P < .001).

CONCLUSION

Maternal history of RPL is associated with a higher risk of future pediatric respiratory morbidity of the offspring; possibly explained by a common immunological etiology.

Hypertensive disorders of pregnancy and risk of asthma in offspring: protocol for a systematic review and meta-analysis

INTRODUCTION

Hypertensive disorders of pregnancy (HDP), one of the most common obstetrical complications, has been reported to have a controversial relationship with the increased risk of asthma in offspring. No systematic review of this topic has been performed. The aim of this systematic review will be to summarise the available evidence examining the association between HDP and the risk of asthma in offspring.

METHODS AND ANALYSIS

We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology guidelines. A systematic search of the PubMed, Embase, Cochrane and Web of Science databases will be performed using a detailed search strategy from database inception through 31 December 2019. Cohort, case-control and cross-sectional studies that report a diagnosis of maternal HDP and asthma in offspring will be included. Studies will be limited to the English language and include only human participants. Two independent reviewers will conduct the study selection, data extraction and risk of bias assessments using a standardised data extraction form. A meta-analysis will be performed to calculate overall pooled estimates using the generic inverse variance method. The data will be synthesised by either fixed-effect or random effects models according to heterogeneity tests. All analyses will be performed in Stata 14 and RevMan 5.3. High-quality evidence of the relationship between HDP and the risk of asthma in exposed offspring will be identified through the synthesis of current studies. In addition, the results of subgroup analyses and related secondary outcomes will be reported. The following will be concluded: (i) whether HDP increases the risk of asthma in offspring, (ii) whether HDP affects the severity of asthma in exposed offspring and (iii) whether possible differences in the risk of asthma among different HDP subgroups exist.

ETHICS AND DISSEMINATION

There is no requirement for ethics approval because the meta-analysis and systematic review will be based on published data. It is anticipated that the dissemination of results will take place at conferences and through publication in a peer-reviewed journal.

Association Between Maternal Perceived Stress in All Trimesters of Pregnancy and Infant Atopic Dermatitis: A Prospective Birth Cohort Study

Background: Currently, most studies indicate that there is a potential link between maternal psychologic stress and the risk of atopic dermatitis (AD) in offspring. However, it is unknown which trimester of pregnancy is most sensitive to maternal stress in terms of risk of infant AD and whether the changes of maternal stress level in different trimesters of pregnancy may be associated with infant AD. In this study, we aimed to investigate the association between maternal perceived stress across three trimesters of pregnancy and AD in infants at 6 months. Methods: A total of 1,638 pregnant women participated in the population-based birth cohort study. Maternal prenatal stress was assessed by self-report questionnaires during each trimester. Infant AD was diagnosed at age 6 months, according to the UK Working Party diagnostic criteria. Univariate and multivariate logistic regression models were used to analyze the association between maternal prenatal stress in each trimester of pregnancy and infant AD. Results: Maternal perceived stress in the 2nd trimester was associated with AD in infants at 6 months (aOR 1.56; 95% CI 1.08-2.25, P = 0.019). Furthermore, increased level of perceived stress from the 1st to the 2nd trimester (aOR 2.05, 95% CI 1.33-3.15, P = 0.001) and from the 1st to the 3rd trimester (aOR 1.92, 95% CI 1.22-3.00, P = 0.004) were also associated with the risk of infant AD at 6 months. Conclusion: A high level of maternal perceived stress in the 2nd trimester and increased level of perceived stress from the 1st to the 2nd and 3rd trimesters of pregnancy may increase the risk of offspring developing AD at 6 months.

Prenatal and neonatal factors involved in the development of childhood allergic diseases in Guangzhou primary and middle school students

BACKGROUND

Allergic diseases, such as asthma, dermatitis, rhinitis, and eczema, are highly prevalent in Chinese school children. Environmental factors, including air pollution and automobile exhaust, play an important role in the etiology of these diseases. However, prenatal and neonatal factors, such as gender, maternal diseases during pregnancy, and premature birth, may also be associated with allergic disease occurrence. The objective of this study was to explore prenatal and neonatal factors that are involved in the development of allergic diseases among primary and middle school students in Guangzhou, China.

METHODS

A cross-sectional survey was launched by the Health Promotion Centre for Primary and Secondary Schools of the Guangzhou Municipality in October 2017. All primary and middle school students in Guangzhou were notified to participate in the questionnaire online under the direction of their parents. The results of the physical examination were reported by the schools' medical department. The results of the questionnaire were collected and analyzed by the researchers. The prevalence of asthma, allergic rhinitis, allergic dermatitis, and eczema was identified.

RESULTS

Based on reported 183,449 questionnaires and medical records, the data indicate that the sex, birth weight, neonatal feeding type, delivery mode, and students' father smoking status were significantly associated with the prevalence of all four allergic diseases in primary and middle school children. In further stratified analyses of the children with normal birth weight (2500-4000 g) and without any maternal diseases during pregnancy, the factors of male sex, high birth weight, cesarean delivery, and father smoking status all increased the risk of asthma, dermatitis, rhinitis, and eczema. Also, unlike exclusive breastfeeding, breast plus formula feeding increased these risks, but pure formula feeding had the opposite effect.

CONCLUSION

Prenatal and neonatal factors, including male sex, high birth weight, cesarean delivery, only child, and father smoking status are associated with the risks of allergic diseases in school children.

Decreased maternal serum acetate and impaired fetal thymic and regulatory T cell development in preeclampsia

Maternal immune dysregulation seems to affect fetal or postnatal immune development. Preeclampsia is a pregnancy-associated disorder with an immune basis and is linked to atopic disorders in offspring. Here we show reduction of fetal thymic size, altered thymic architecture and reduced fetal thymic regulatory T (Treg) cell output in preeclamptic pregnancies, which persists up to 4 years of age in human offspring. In germ-free mice, fetal thymic CD4+ T cell and Treg cell development are compromised, but rescued by maternal supplementation with the intestinal bacterial metabolite short chain fatty acid (SCFA) acetate, which induces upregulation of the autoimmune regulator (AIRE), known to contribute to Treg cell generation. In our human cohorts, low maternal serum acetate is associated with subsequent preeclampsia, and correlates with serum acetate in the fetus. These findings suggest a potential role of acetate in the pathogenesis of preeclampsia and immune development in offspring.

Asthma in Children and Adults-What Are the Differences and What Can They Tell us About Asthma?

Asthma varies considerably across the life course. Childhood asthma is known for its overall high prevalence with a male predominance prior to puberty, common remission, and rare mortality. Adult asthma is known for its female predominance, uncommon remission, and unusual mortality. Both childhood and adult asthma have variable presentations, which are described herein. Childhood asthma severity is associated with duration of asthma symptoms, medication use, lung function, low socioeconomic status, racial/ethnic minorities, and a neutrophilic phenotype. Adult asthma severity is associated with increased IgE, elevated FeNO, eosinophilia, obesity, smoking, and low socioeconomic status. Adult onset disease is associated with more respiratory symptoms and asthma medication use despite higher prebronchodilator FEV1/FVC. There is less quiescent disease in adult onset asthma and it appears to be less stable than childhood-onset disease with more relapses and less remissions.

Associations of Preeclampsia with Expiratory Airflows in School-Age Children Born Either at <28 Weeks or Weighing <1000 g

OBJECTIVES

To assess whether preeclampsia was associated with expiratory airflow at school-age in children born either extremely preterm (<28 weeks of gestation) or extremely low birthweight (ELBW; <1000 g birth weight).

STUDY DESIGN

Participants comprised 3 cohorts of children born extremely preterm/ELBW in the state of Victoria, Australia, in 1991-1992, 1997, or 2005. Expiratory airflows were measured at age 8 years, and results converted to z scores. Data were compared between those exposed to preeclampsia with those unexposed to preeclampsia; analyses were then adjusted for confounding perinatal variables. Analyses were repeated within subgroups of extremely preterm only and ELBW only.

RESULTS

Respiratory data were available for 544 of 717 (76%) survivors, of whom 95 (17%) had been exposed to preeclampsia. On univariable analysis, those exposed to preeclampsia had better z scores for flows for the forced expired volume in 1 second (zFEV₁) (mean difference 0.29, 95% CI 0.04-0.53; P = .022) and zFEV₁/forced vital capacity (mean difference 0.33, 95% CI 0.04-0.61; P = .025); the difference persisted for zFEV₁ after adjustment for confounding perinatal variables. Analyses confined to those born extremely preterm revealed little evidence for associations between preeclampsia and airflow. In analyses confined to those born ELBW, preeclampsia was associated with better zFEV₁, which persisted after adjustment (mean difference 0.33, 95% CI 0.04-0.63; P = .025).

CONCLUSIONS

Exposure to maternal preeclampsia was not associated with worse expiratory airflow in children born extremely preterm/ELBW; in fact, some airflows were better.

Levels of Systemic Low-grade Inflammation in Pregnant Mothers and Their Offspring are Correlated

High sensitivity C-reactive protein (hs-CRP) is a marker of systemic low-grade inflammation and associated with chronic inflammatory diseases. It is unknown whether maternal and infant hs-CRP levels are correlated and little is known about risk factors in early childhood. Hs-CRP were measured in mothers during pregnancy week 24 (N = 690), and one-week postpartum (N = 675) and in their children age 6 mo (N = 640) enrolled in the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) cohort. The risk factor analysis included anthropometrics, environmental exposures and CRP-Genetic Risk Score (GRS). Mother's body mass index (BMI), use of antibiotics, smoking, cesarean delivery and season were associated with higher maternal hs-CRP level, whereas higher social circumstances were associated with lower hs-CRP level (p < 0.05). Child's BMI, siblings, bacterial airway colonization, current infection, CRP-genetic risk score and season were associated with higher hs-CRP at age 6 mo (all p < 0.05). Mother's hs-CRP level in pregnancy week 24 was associated with hs-CRP level in the child at 6 mo: β-coefficient = 0.11 [95% CI: 0.01-0.20], R2 = 0.22, p = 0.03. The association was unchanged adjusted for all significant risk factors. Systemic low-grade inflammation in pregnant mothers and their offspring is correlated independently of BMI, environmental exposures and genetic risk factors.

Impact of Preeclampsia on the Relationship between Maternal Asthma and Offspring Asthma. An Observation from the VDAART Clinical Trial

RATIONALE

Maternal asthma and preeclampsia have independently been reported to be associated with increased asthma incidence in children of affected mothers. Maternal asthma is also associated with increased risk of preeclampsia development. However, the joint effect of these maternal conditions on child asthma risk is unknown.

OBJECTIVES

To study whether development of preeclampsia among pregnant women with asthma was associated with higher risk of childhood asthma in the VDAART (Vitamin D Antenatal Asthma Reduction Trial).

METHODS

A total of 806 pregnant women and their offspring at high risk of asthma or atopy, who were followed from VDAART enrollment (10-18 wk of gestation) through the child's third birthday, were included in this cohort analysis. Preeclampsia status was determined by chart review, obstetrician diagnosis, and adjudication by a panel of obstetricians. Child asthma was the main outcome as determined by parental report of a physician diagnosis, and the risk of child asthma was also examined if accompanied by recurrent wheeze. The main risk variable of interest was a four-level ordered variable defined for each mother, with values without asthma without preeclampsia, without asthma with preeclampsia, with asthma without preeclampsia, and with asthma with preeclampsia during their pregnancy. We examined the trend of outcome proportions across these categories. To account for differences in maternal and child characteristics, we used a Weibull regression model for interval-censored data to compare the incidence of child asthma by age of 3 years across the maternal variable categories.

MEASUREMENTS AND MAIN RESULTS

The incidence of asthma in 3-year-old children was 9.90% (44/445), 17.95% (7/39), 22.11% (65/294), and 32.14% (9/28) among those born to mothers without asthma and without preeclampsia, mothers without asthma with preeclampsia, mothers with asthma without preeclampsia, and mothers with asthma with preeclampsia, respectively. The incidences demonstrated an increasing trend in risk of child asthma across the maternal groups (P for trend <0.001). After accounting for potential confounders and using time to report of childhood asthma as analysis outcome, risk of asthma was greater among children born to mothers with asthma without preeclampsia, compared with mothers without asthma without preeclampsia (adjusted hazard ratio, 2.18; 95% confidence interval, 1.46-3.26). This risk was 50% greater for children born to mothers with asthma who developed preeclampsia during pregnancy (adjusted hazard ratio, 2.68; 95% confidence interval, 1.30-5.61). The trend in asthma and recurrent wheeze proportions across the maternal groups' children also indicated a higher risk for children born to mothers with asthma with preeclampsia (adjusted hazard ratio, 4.73; 95% confidence interval, 2.20-10.07; P for trend <0.001).

CONCLUSIONS

Preeclampsia is associated with increased risk of early life childhood asthma in children less than 3 years old over and above that associated with maternal asthma alone. The results implicate the interplay between maternal factors as strong predictors of offspring asthma and in utero maternal-fetal immune perturbations and developmental dysregulations associated with preeclampsia.

Maternal blood pressure and hypertensive disorders during pregnancy and childhood respiratory morbidity: the Generation R Study

Pre-eclampsia is associated with an increased risk of bronchopulmonary dysplasia, wheezing and asthma in later childhood. Currently, there are no studies available investigating maternal blood pressure measurements during multiple time-points in pregnancy and respiratory outcome measures in the child.We examined the associations of maternal blood pressure and hypertensive disorders with the risk of lower lung function, wheezing and asthma in children aged 10 years. This study among 4894 children was embedded in a population-based prospective cohort study. We used multivariate analyses, taking lifestyle and socioeconomic factors into account.We observed consistent associations per 5 mmHg higher maternal blood pressure in early pregnancy with a lower forced expiratory volume in 1 s/forced vital capacity ratio (z-score -0.03 (95% CI -0.05- -0.01)) and per 5 mmHg higher blood pressure in late pregnancy with a higher risk for current wheezing and current asthma (OR 1.07 (95% CI 1.02-1.12) and 1.06 (95% CI 1.00-1.11), respectively). We found no associations of maternal hypertensive disorders during pregnancy with child lung function, current wheezing or current asthma.Our results suggest that higher blood pressure in pregnant women is associated with lower lung function and increased risks of current wheezing and current asthma in children. The associations may be trimester specific.

Maternal Cytokine Profiles during Pregnancy Predict Asthma in Children of Mothers without Asthma

Little is known about whether maternal immune status during pregnancy influences asthma development in the child. We measured cytokine production in supernatants from mitogen-stimulated peripheral blood immune cells collected during and after pregnancy from the mothers of children enrolled in the Tucson Infant Immune Study, a nonselected birth cohort. Physician-diagnosed active asthma in children through age 9 and a history of asthma in their mothers were assessed through questionnaires. Maternal production of each of the cytokines IL-13, IL-4, IL-5, IFN-γ, IL-10, and IL-17 during pregnancy was unrelated to childhood asthma. However, IFN-γ/IL-13 and IFN-γ/IL-4 ratios during pregnancy were associated with a decreased risk of childhood asthma (n = 381; odds ratio [OR], 0.33; 95% confidence interval [CI], 0.17-0.66; P = 0.002; and n = 368; OR, 0.36; 95% CI, 0.18-0.71; P = 0.003, respectively). The inverse relations of these two ratios with childhood asthma were only evident in mothers without asthma (n = 309; OR, 0.18; 95% CI, 0.08-0.42; P = 0.00007; and n = 299; OR, 0.17; 95% CI, 0.07-0.39; P = 0.00003, respectively) and not in mothers with asthma (n = 72 and 69, respectively; P for interaction by maternal asthma = 0.036 and 0.002, respectively). Paternal cytokine ratios were unrelated to childhood asthma. Maternal cytokine ratios in mothers without asthma were unrelated to the children's skin-test reactivity, total IgE, physician-confirmed allergic rhinitis at age 5, or eczema in infancy. To our knowledge, this study provides the first evidence that cytokine profiles in pregnant mothers without asthma relate to the risk for childhood asthma, but not allergy, and suggests a process of asthma development that begins in utero and is independent of allergy.

Pregnancy complications, treatment characteristics and birth outcomes in women with atopic dermatitis in Denmark

BACKGROUND

The risk of prenatal, obstetric and birth complications in mothers with atopic dermatitis (AD), along with treatment use during pregnancy, is unknown.

OBJECTIVES

To examine the associations between prenatal, obstetric and birth complications in mothers with AD and describe the dermatologic care received during pregnancy.

METHODS

Mother-child pairs, in which the mother had a history of AD, were identified through the Danish Medical Birth Registry and matched 1 : 10 with non-AD pairs. Data on dermatologic treatment and prenatal, obstetric and birth complications were obtained through linkage via nationwide registers. Multiple logistic regression was performed.

RESULTS

We identified 10 668 births from 1997 through 2014 to women with AD. Women with a hospital/ambulatory contact for AD during pregnancy had increased topical corticosteroid and ultraviolet therapy use during pregnancy compared to prior. However, overall, women with AD received decreased dermatologic therapy during pregnancy compared to prior. In adjusted analysis, maternal AD was inversely associated with gestational diabetes [OR 0.79, 95% CI (0.68-0.92)], but positively associated with premature rupture of membranes [1.15 (1.05-1.27)] and staphylococcal neonatal septicemia [2.45 (1.33-4.49)]-albeit the latter was rare. These associations did not meet statistical significance in sub-analysis where body mass index data were available. No associations were found with preeclampsia, prematurity or non-staphylococcal neonatal septicaemia.

CONCLUSIONS

Women with AD during pregnancy mainly used topical corticosteroids and ultraviolet therapy to control their disease. While premature rupture of membranes and staphylococcal neonatal septicaemia were over-represented in maternal AD, no associations were found with any other significant prenatal, obstetric or birth outcome.

The association of prenatal risk factors with childhood asthma

Objective: The purpose of the study was to examine the relationship of maternal complications during pregnancy and prenatal exposures with childhood asthma among low-income families in Karachi, Pakistan. Methods: Parents/guardians of children with and without asthma visiting a charity hospital were enrolled. Information about prenatal and perinatal exposures was collected. Univariable and multiple stepwise logistic regression analysis were conducted to explore the relationship of socio-demographic, maternal complications during pregnancy, access to prenatal care, and exposure to animals and pests while pregnant with childhood asthma. Results: Maternal symptoms of nocturnal cough (adjusted OR [aOR = 2.87, 95% CI = 1.60-5.14) and wheezing (aOR = 5.57, 95% CI = 2.32-13.37) during pregnancy significantly increased the odds of childhood asthma. The family history of asthma or hay fever, also elevated the odds of childhood asthma (adjusted OR [aOR] = 5.86 (3.03-11.34). The odds of asthma among children whose mothers received prenatal care by Dai, an unskilled health worker, were significantly elevated. Lastly, prenatal exposure to rats/mice and contact with goats while pregnant was significantly associated with childhood asthma. Whereas, prenatal exposure to cows/cattle reduces the odds of childhood asthma. Conclusions: This study identified important maternal and prenatal risk factors for childhood asthma, the majority of which are avoidable. Appropriate steps are needed to create awareness about the prenatal risk factors in this population.

Maternal allergy as an isolated risk factor for early-onset preeclampsia: An epidemiological study

Immunological mechanisms underlying the development of preeclampsia are well known, but no association to allergy has yet been demonstrated. The aim of this study was to assess the correlation between maternal pre-gestational allergy, and early-onset and late-onset preeclampsia, respectively. It was a retrospective cohort study including all women giving birth in the Norwegian cities of Stavanger (1996-2014) and Bergen (2009-2014). Pre-gestational asthma, allergy, other known risk factors for preeclampsia, maternal age and parity were obtained from the electronic medical record system. The main outcome variables were early-onset and late-onset preeclampsia (before and after 34 completed weeks of gestation, respectively). We used multinomial logistic regression to estimate odds ratios (OR) with 95% confidence intervals (95% CI) for early and late-onset preeclampsia in women with pre-gestational allergy when compared to women without allergy, adjusting for covariates. Predicted probabilities for the outcomes were also calculated. Of the 110 064 included pregnancies, 2 799 developed late-onset preeclampsia (2.5%) and 348 developed early-onset preeclampsia (0.3%). Pre-gestational allergy increased the risk of early-onset preeclampsia (OR 1.7, 95% CI 1.3-2.4), and reduced the risk of late-onset preeclampsia (OR 0.8, 95% CI 0.7-0.9). These findings add valuable information on preeclampsia as an immunological complication of pregnancy and corroborate the understanding of early- and late-onset preeclampsia as two different entities.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.

The maternal microbiome during pregnancy and allergic disease in the offspring

There is substantial epidemiological and mechanistic evidence that the increase in allergic disease and asthma in many parts of the world in part relates to changes in microbial exposures and diet acting via the composition and metabolic products of the intestinal microbiome. The majority of research in this field has focused on the gut microbiome during infancy, but it is increasingly clear that the maternal microbiome during pregnancy also has a key role in preventing an allergy-prone immune phenotype in the offspring. The mechanisms by which the maternal microbiome influences the developing fetal immune system include alignment between the maternal and infant regulatory immune status and transplacental passage of microbial metabolites and IgG. Interplay between microbial stimulatory factors such as lipopolysaccharides and regulatory factors such as short-chain fatty acids may also influence on fetal immune development. However, our understanding of these pathways is at an early stage and further mechanistic studies are needed. There are also no data from human studies relating the composition and metabolic activity of the maternal microbiome during pregnancy to the offspring's immune status at birth and risk of allergic disease. Improved knowledge of these pathways may inform novel strategies for tackling the increase in allergic disorders in the modern world.

The validity of register data to identify children with atopic dermatitis, asthma or allergic rhinoconjunctivitis

BACKGROUND

The incidence of atopic dermatitis, wheezing, asthma and allergic rhinoconjunctivitis has been increasing. Register-based studies are essential for research in subpopulations with specific diseases and facilitate epidemiological studies to identify causes and evaluate interventions. Algorithms have been developed to identify children with atopic dermatitis, asthma or allergic rhinoconjunctivitis using register information on disease-specific dispensed prescribed medication and hospital contacts, but the validity of the algorithms has not been evaluated. This study validated the algorithms vs gold standard deep telephone interviews with the caretaker about physician-diagnosed atopic dermatitis, wheezing, asthma or allergic rhinoconjunctivitis in the child.

METHODS

The algorithms defined each of the three atopic diseases using register-based information on disease-specific hospital contacts and/or filled prescriptions of disease-specific medication. Confirmative answers to questions about physician-diagnosed atopic disease were used as the gold standard for the comparison with the algorithms, resulting in sensitivities and specificities and 95% confidence intervals. The interviews with the caretaker of the included 454 Danish children born 1997-2003 were carried out May-September 2015; the mean age of the children at the time of the interview being 15.2 years (standard deviation 1.3 years).

RESULTS

For the algorithm capturing children with atopic dermatitis, the sensitivity was 74.1% (95% confidence interval: 66.9%-80.2%) and the specificity 73.0% (67.3%-78.0%). For the algorithm capturing children with asthma, both the sensitivity of 84.1% (78.0%-88.8%) and the specificity of 81.6% (76.5%-85.8%) were high compared with physician-diagnosed asthmatic bronchitis (recurrent wheezing). The sensitivity remained high when capturing physician-diagnosed asthma: 83.3% (74.3%-89.6%); however, the specificity declined to 66.0% (60.9%-70.8%). For allergic rhinoconjunctivitis, the sensitivity was 84.4% (78.0-89.2) and the specificity 81.6% (75.0-84.4).

CONCLUSION

The algorithms are valid and valuable tools to identify children with atopic dermatitis, wheezing, asthma or allergic rhinoconjunctivitis on a population level using register data.

Applications of Metabolomics in the Study and Management of Preeclampsia; A Review of the Literature

Introduction

Preeclampsia represents a major public health burden worldwide, but predictive and diagnostic biomarkers are lacking. Metabolomics is emerging as a valuable approach to generating novel biomarkers whilst increasing the mechanistic understanding of this complex condition.

Objectives

To summarize the published literature on the use of metabolomics as a tool to study preeclampsia.

Methods

PubMed and Web of Science were searched for articles that performed metabolomic profiling of human biosamples using either Mass-spectrometry or Nuclear Magnetic Resonance based approaches and which included preeclampsia as a primary endpoint.

Results

Twenty-eight studies investigating the metabolome of preeclampsia in a variety of biospecimens were identified. Individual metabolite and metabolite profiles were reported to have discriminatory ability to distinguish preeclamptic from normal pregnancies, both prior to and post diagnosis. Lipids and carnitines were among the most commonly reported metabolites. Further work and validation studies are required to demonstrate the utility of such metabolites as preeclampsia biomarkers.

Conclusion

Metabolomic-based biomarkers of preeclampsia have yet to be integrated into routine clinical practice. However, metabolomic profiling is becoming increasingly popular in the study of preeclampsia and is likely to be a valuable tool to better understand the pathophysiology of this disorder and to better classify its subtypes, particularly when integrated with other omic data.