Pregnancy Complications and Wheezing and Asthma in Childhood

The impact of maternal asthma on the fetal lung: Outcomes, mechanisms and interventions

Maternal asthma affects up to 17% of pregnancies and is associated with adverse infant, childhood, and adult respiratory outcomes, including increased risks of neonatal respiratory distress syndrome, childhood wheeze and asthma. In addition to genetics, these poor outcomes are likely due to the mediating influence of maternal asthma on the in-utero environment, altering fetal lung and immune development and predisposing the offspring to later lung disease. Maternal asthma may impair glucocorticoid signalling in the fetus, a process critical for lung maturation, and increase fetal exposure to proinflammatory cytokines. Therefore, interventions to control maternal asthma, increase glucocorticoid signalling in the fetal lung, or Vitamin A, C, and D supplementation to improve alveologenesis and surfactant production may be beneficial for later lung function. This review highlights potential mechanisms underlying maternal asthma and offspring respiratory morbidities and describes how pregnancy interventions can promote optimal fetal lung development in babies of asthmatic mothers.

Maternal gestational diabetes mellitus and the childhood asthma in offspring: a meta-analysis

BACKGROUND

Maternal diabetes might be related to a high risk of allergic disease in offspring. However, it remains unknown if maternal gestational diabetes mellitus (GDM) is also associated with a high incidence of childhood asthma in offspring. A systematic review and meta-analysis was performed to investigate the above association.

METHODS

Relevant observational studies were obtained by search of electronic databases including Medline, Embase, Cochrane Library, and Web of Science. A randomized-effects model was selected to pool the data by incorporating the influence of potential heterogeneity. The Newcastle-Ottawa Scale was used for study quality evaluation. Subgroup analyses were performed to evaluate the potential influences of study characteristics on the outcome.

RESULTS

Ten datasets from seven moderate to high quality cohort studies, involving 523,047 mother-child pairs were included in the meta-analysis. Overall, maternal GDM was associated with a higher risk of childhood asthma in offspring (risk ratio [RR]: 1.22, 95% confidence interval [CI]: 1.07 to 1.39, p = 0.003; I2 = 30%). Subgroup analyses showed that the association was not significantly affected by study design, validation methods for GDM, or diagnostic strategy for asthma (p for subgroup analyses all > 0.05). The association between maternal GDM and asthma in offspring was more remarkable after adjusting maternal body mass index in early pregnancy (RR: 1.50 versus 1.06, p < 0.001), but significantly weakened after adjusting hypertensive disorders during pregnancy (RR: 1.08 versus 1.50, p = 0.001).

CONCLUSIONS

Maternal GDM may be associated with an increased incidence of childhood asthma in offspring.

Perinatal maternal mental health is associated with both infections and wheezing in early childhood

BACKGROUND

Wheezing and infections are common during infancy, and the role of early-life exposures in their development is still under investigation. We examined associations between maternal mental health in pregnancy and after delivery and subsequent offspring wheezing and infections.

METHODS

We studied 2314 mother-child pairs recruited in the Piccolipiù birth cohort (Italy) from 2011 to 2015. Maternal mental health was assessed in pregnancy and 12 months after delivery via the General Health Questionnaire-12 (GHQ-12). GHQ-12 Likert scores were collapsed into low (below the upper tercile) and high (above). Risk ratios (RR) and 95% confidence intervals (CI) between each combination of scores-during pregnancy and 1 year after delivery-and outcomes were computed by log-binomial regression models.

RESULTS

High scores both in pregnancy and after delivery, compared with low scores in both periods, were associated with wheezing (RR: 1.35; 95% CI: 1.08, 1.69), recurrent (≥2 episodes) wheezing (1.35; 0.99, 1.83), any and recurrent (≥4 episodes) upper respiratory infections (1.20; 1.04, 1.41, and 1.45; 1.07, 1.97, respectively), lower respiratory infections (1.31; 1.08, 1.61), and diarrhea (1.49; 1.23, 1.80). High scores either during pregnancy or 1 year after delivery only were less consistently associated with outcomes.

CONCLUSIONS

Maternal mental health problems extending from pregnancy to the first year after delivery are associated with development of both wheezing and infections. As wheezing is mostly triggered by infections, increased infection susceptibility could represent a possible common biologic mechanism. This study confirms the importance of early-life exposures on childhood health.

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 psychological distress during pregnancy and childhood health outcomes: a narrative review

Maternal psychological distress is common in pregnancy and may influence the risk of adverse outcomes in children. Psychological distress may cause a suboptimal intrauterine environment leading to growth and developmental adaptations of the fetus and child. In this narrative review, we examined the influence of maternal psychological distress during pregnancy on fetal outcomes and child cardiometabolic, respiratory, atopic and neurodevelopment-related health outcomes. We discussed these findings from an epidemiological and life course perspective and provided recommendations for future studies. The literature in the field of maternal psychological distress and child health outcomes is extensive and shows that exposure to stress during pregnancy is associated with multiple adverse child health outcomes. Because maternal psychological distress is an important and potential modifiable factor during pregnancy, it should be a target for prevention strategies in order to optimize fetal and child health. Future studies should use innovative designs and strategies in order to address the issue of causality.

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.

The role of maternal anorexia nervosa and bulimia nervosa before and during pregnancy in early childhood wheezing: Findings from the NINFEA birth cohort study

OBJECTIVE

This study evaluates associations of maternal eating disorders (bulimia nervosa, anorexia nervosa, and purging behaviors) with infant wheezing and examines the effects of eating disorders on several wheezing determinants.

METHOD

We studied 5,150 singletons from the NINFEA birth cohort. Maternal bulimia nervosa and anorexia nervosa diagnoses were ascertained from the questionnaires completed in pregnancy and 6 months after delivery, and were analyzed as: ever diagnosis, only before pregnancy, and during pregnancy. Purging behaviors were assessed for 12 months before or during pregnancy. The associations with wheezing between 6 and 18 months of age were assessed in models adjusted for a priori selected confounders.

RESULTS

Children born to mothers with lifetime eating disorders were at an increased risk of developing wheezing (adjusted OR 1.68; [95% CI: 1.08, 2.60]), and this risk further increased when the disorders were active during pregnancy (2.52 [1.23, 5.19]). Increased risk of offspring wheezing was observed also for purging behaviors without history of eating disorder diagnosis (1.50 [1.10, 2.04]). The observed associations were not explained by comorbid depression and/or anxiety. Bulimia nervosa and/or anorexia nervosa during pregnancy were also associated with several risk factors for wheezing, including maternal smoking, adverse pregnancy outcomes, shorter breastfeeding duration, and day-care attendance.

DISCUSSION

The associations of maternal eating disorders with offspring wheezing suggest long-term adverse respiratory outcomes in children of mothers with eating disorders. A better understanding of mechanisms implicated is necessary to help reduce the respiratory disease burden in these children.