Maternal adiposity in pregnancy and offspring asthma in adulthood

Cohort Study of Maternal Gestational Weight Gain, Gestational Diabetes, and Childhood Asthma

Data on the association of maternal gestational weight gain (GWG) and gestational diabetes mellitus (GDM) with childhood asthma are limited and inconsistent. We aimed to investigate these associations in a U.S. pre-birth cohort. Analyses included 16,351 mother-child pairs enrolled in the Massachusetts General Hospital Maternal-Child Cohort (1998-2010). Data were obtained by linking electronic health records for prenatal visits/delivery to determine BMI, GWG, and GDM (National Diabetes Data Group criteria) and to determine asthma incidence and allergies (atopic dermatitis or allergic rhinitis) for children. The associations of prenatal exposures with asthma were evaluated using logistic regression adjusted for maternal characteristics. A total of 2306 children (14%) developed asthma by age 5 years. Overall, no association was found between GWG and asthma. GDM was positively associated with offspring asthma (OR 1.46, 95% CI 1.14-1.88). Associations between GDM and asthma were observed only among mothers with early pregnancy BMI between 20 and 24.9 kg/m² (OR 2.31, CI 1.46-3.65, p-interaction 0.02). We report novel findings on the impact of prenatal exposures on asthma, including increased risk among mothers with GDM, particularly those with a normal BMI. These findings support the strengthening of interventions targeted toward a healthier pregnancy, which may also be helpful for childhood asthma prevention.

Trends in maternal body mass index in Northern Ireland: a cross-sectional and longitudinal study

Objectives

Explore (1) associations between maternal body mass index (BMI), demographic and clinical characteristics, (2) longitudinal trends in BMI, (3) geographical distributions in prevalence of maternal overweight and obesity.

Design

Retrospective population-based study.

Setting

Linked, anonymised, routinely collected healthcare data and official statistics from Northern Ireland.

Participants

All pregnancies in Northern Ireland (2011–2017) with BMI measured at ≤16 weeks gestation.

Methods

Analysis of variance and χ² tests were used to explore associations. Multiple linear regression was used to explore longitudinal trends and spatial visualisation illustrated geographical distribution. Main outcomes are prevalence of overweight (BMI ≥25 kg/m²) and obesity (BMI ≥30 kg/m²).

Results

152 961 singleton and 2362 multiple pregnancies were included. A high prevalence of maternal overweight and obesity in Northern Ireland is apparent (singleton: 52.4%; multiple: 48.3%) and is increasing. Obesity was positively associated with older age, larger numbers of previous pregnancies and unplanned pregnancy (p<0.001). BMI category was also positively associated with unemployment (35% in obese class III vs 22% in normal BMI category) (p<0.001). Higher BMI categories were associated with increased rate of comorbidities, including hypertension (normal BMI: 1.8% vs obese III: 12.4%), diabetes mellitus (normal BMI: 0.04% vs obese III: 1.29%) and mental ill-health (normal BMI: 5.0% vs obese III: 11.8%) (p<0.001). Prevalence of maternal obesity varied with deprivation (most deprived: 22.8% vs least deprived: 15.7%) (p<0.001). Low BMI was associated with age <20 years, nulliparity, unemployment and mental ill-health (p<0.001).

Conclusions

The prevalence of maternal BMI >25 kg/m² is increasing over time in Northern Ireland. Women are entering pregnancy with additional comorbidities likely to impact their life course beyond pregnancy. This highlights the need for prioritisation of preconception and inter-pregnancy support for management of weight and chronic conditions.

Leptin in Cord Blood Associates with Asthma Risk at Age 3 in the Offspring of Women with Gestational Obesity

Rationale: Maternal obesity is associated with asthma in the offspring. Whether cord blood leptin is associated with risk of asthma in offspring is unclear.Objectives: To assess whether cord blood leptin from women with pregestational obesity predict preschool asthma.Methods: In this birth cohort study, we divided pregnant women into three weight categories during the first obstetric visit: normal (NL), overweight (OW), and obese (OB).Results: We followed the offspring recording atopy, wheezing, and other respiratory illnesses through 30 months of age. Cord blood and peripheral blood at 30 months of age were taken to measure cytokines, adipokines, metabolic biomarkers, and specific immunoglobulin E. Adjusted regression models were used to evaluate the association between maternal obesity and offspring asthma risk, defined by a positive Asthma Predictive Index. Three hundred thirty-nine mothers were recruited; 140 offspring were born from NL, 80 from OW, and 119 from OB mothers. OB women were older and less educated and had higher parity and higher C-section frequency. Offspring from OB women had higher birthweight, head circumference, and placental weight compared with other groups. The proportion of Asthma Predictive Index positive at 30 months of age was 12.2% in the NL, 14.7% in the OW, and 16.8% in the OB group (P = 0.18). Offspring from OB women had higher leptin, leptin/adiponectin ratio, interleukin-10, and insulin than the OW group and higher leptin than the NL group. In the adjusted analysis, offspring from OB mothers with high cord blood leptin had increased risk of asthma (adjusted odds ratio, 1.30; 95% confidence interval, 1.1-1.55; P = 0.003).Conclusions: Offspring from obese mothers with high cord blood leptin have 30% higher asthma risk at age 3.Clinical trial registered with ClinicalTrials.gov (NCT02903134).

Prenatal oxidative balance and risk of asthma and allergic disease in adolescence

BACKGROUND

Fetal oxidative balance (achieved when protective prenatal factors counteract sources of oxidative stress) might be critical for preventing asthma and allergic disease.

OBJECTIVE

We examined prenatal intakes of hypothesized protective nutrients (including antioxidants) in conjunction with potential sources of oxidative stress in models of adolescent asthma and allergic disease.

METHODS

We used data from 996 mother-child pairs in Project Viva. Exposures of interest were maternal prepregnancy body mass index and prenatal nutrients (energy-adjusted intakes of vitamins D, C, and E; β-carotene; folate; choline; and n-3 and n-6 polyunsaturated fatty acids [PUFAs]), air pollutant exposures (residence-specific third-trimester black carbon or particulate matter with a diameter of less than 2.5 μm [PM2.5]), acetaminophen, and smoking. Outcomes were offspring's current asthma, allergic rhinitis, and allergen sensitization at a median age of 12.9 years. We performed logistic regression. Continuous exposures were log-transformed and modeled as z scores.

RESULTS

We observed protective associations for vitamin D (odds ratio [OR], 0.69 [95% CI, 0.53-0.89] for allergic rhinitis), the sum of the n-3 PUFAs eicosapentaenoic acid and docosahexaenoic acid (OR, 0.81 [95% CI, 0.66-0.99] for current asthma), and the n-3 PUFA α-linolenic acid (OR, 0.78 [95% CI, 0.64-0.95] for allergen sensitization and OR, 0.80 [95% CI 0.65-0.99] for current asthma). Black carbon and PM2.5 were associated with an approximately 30% increased risk for allergen sensitization. No multiplicative interactions were observed for protective nutrient intakes with sources of oxidative stress.

CONCLUSIONS

We identified potential protective prenatal nutrients (vitamin D and n-3 PUFAs), as well as adverse prenatal pro-oxidant exposures that might alter the risk of asthma and allergic disease into adolescence.