Exposure to O3 during pregnancy and offspring asthma induced by OVA: Sensitive window identification

Global burden of asthma among children and adolescents with projections to 2050: a comprehensive review and forecasted modeling study

Understanding pediatric asthma is crucial to its effective diagnosis and intervention, as it may alleviate the adulthood disease burden. This epidemiological review describes the prevalence of asthma among individuals under 20 years of age by categorizing them into 3 age groups: 1-4, 5-9, and 10-19 years. Estimates were obtained from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, which covered the prevalence of asthma from 1990 to 2021 across 21 GBD regions with 95% uncertainty intervals (UIs). We also projected the prevalence of pediatric asthma in 2050 by using a logistic regression predictive model from the existing literature and incorporating body mass index as a covariate with fixed coefficients over time. Overall, a continuous decline in asthma prevalence rates among children and adolescents was observed from 1990 to 2021, with higher rates in males and a peak prevalence rate in the 5-9 years group. Central Europe showed significantly increased prevalence rates compared to those of other regions. Our projection suggests that the prevalence rate of pediatric asthma will decline to approximately 2,608.05 per 100,000 population by 2050 (95% UI, 1,632.94-3,868.26), representing a 39.5% decrease from the 2021 figures. Despite these trends, asthma remains a substantial health burden for children and adolescents that may persist into adulthood. Therefore, proactive diagnosis and intervention are essential to mitigating the associated disease burden.

Prenatal ozone exposure and child lung function: Exploring effect modification by oxidative balance score

BACKGROUND

Prenatal exposures to ozone (O3) may impact child lung function, including through oxidative stress pathways, contributing to lifelong morbidity. Diet, reflected in oxidative balance scores (OBS), may modify these pathways and is a potential target for interventions to mitigate O3 effects.

METHODS

We examined associations between prenatal exposure to O3 and child lung function at age 8-9 years via spirometry in the CANDLE cohort within the ECHO-PATHWAYS Consortium. O3 was estimated using a point-based spatiotemporal model and averaged over fetal morphological lung development phases: pseudoglandular, canalicular, and saccular. Lung function z-scores were calculated for FEV1, FVC, FEV1/FVC, and FEF25-75. OBS during pregnancy was derived using maternal diet and lifestyle factors. Linear regression models adjusted for child, maternal, and neighborhood characteristics and exposure in other prenatal windows. Using two and three-way multiplicative interaction terms, we explored effect modification by OBS and maternal race.

RESULTS

Women (N = 661) self-identified as Black (61%), White (33%), or another race (6%); 40.7% attended some college/technical school. Mean O3 concentrations ranged from 26.1 to 29.5 ppb across exposure windows. No associations between prenatal O3 exposure and lung function were observed in primary models, although there was a suggestive adverse association of 10 ppb higher O3 in the saccular window (24-35 weeks) with lower z-scores for FEV1/FVC (-0.23, 95% CI: -0.52, 0.05) and FEF25-75 (-0.17, 95% CI: -0.43, 0.09). No effect modification by OBS or maternal race was found in two-way models. In three-way interaction models, higher O3 was associated with lower child FEV1 among Black women with lower OBS and among White women with higher OBS although data was sparse for those with the highest OBS.

CONCLUSIONS

In a large, well-characterized pregnancy cohort, we did not find robust evidence of an effect of prenatal O3 on lung function. There was suggestion of enhanced vulnerability for some subgroups in exploratory analyses.

Association analysis of maternal exposure to air pollution during pregnancy and offspring asthma incidence

BACKGROUND

Air pollution has a significant negative impact on human health. Pregnant mothers and children are typical susceptible groups, and environmental exposure has a crucial impact on children's health. We established a childhood asthma cohort to analyze the factors influencing the development of asthma in offspring, with a focus on prenatal exposure to air pollutants. The goal was to explore potential early preventive measures to reduce the incidence of childhood asthma.

METHODS

This nested case-control study included mothers who were registered and delivered at Lianyungang Maternal and Child Health Hospital between 2015 and 2018, covering pre-pregnancy, first, second, and third trimesters. Children diagnosed with asthma before the age of four were included in the asthma group. To assess environmental exposure, we gathered data from 29 national and provincial air pollution monitoring stations and 16 meteorological monitoring sites in Lianyungang and surrounding areas. We used spatial interpolation with inverse distance weighting (IDW) to estimate individual exposure to air pollutants, including particulate matter (PM2.5, PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3). Univariate and multivariate regression analyses were conducted to examine the association between maternal exposure during pregnancy and the risk of childhood asthma.

RESULTS

A total of 292 mother-child pairs in the asthma group and 1423 mother-child pairs in the healthy control group were included. The second (AOR = 1.04, 95%CI 1.01-1.06) and whole gestation (AOR = 1.06, 95%CI 1.03-1.10) exposure to PM2.5 was associated with higher odds of childhood-onset asthma. Exposure during the third trimester (AOR = 1.02, 95%CI 1.01-1.03) and whole gestation (AOR = 1.02, 95%CI 1.01-1.04) of PM10 was associated with higher odds of childhood-onset asthma. The first (AOR = 1.06, 95%CI 1.02-1.09) and second (AOR = 0.95, 95%CI 0.92-0.98) trimesters exposure to NO2 was associated with higher and lower odds of childhood-onset asthma, respectively. SO2 whole pregnancy exposure (AOR = 1.04, 95%CI 1.01-1.07) was associated with higher odds of childhood-onset asthma.

CONCLUSIONS

Exposure to PM2.5, PM10, and SO2 during pregnancy can lead to an elevated risk of childhood asthma. Reducing or avoiding exposure to pollutants during pregnancy can reduce the incidence of childhood asthma. We should protect the environment and reduce the harm of environmental pollution to health.

Prenatal Origins of Obstructive Airway Disease: Starting on the Wrong Trajectory?

From the results of well-performed population health studies, we now have excellent data demonstrating that deficits in adult lung function may be present early in life, possibly as a result of developmental disorders, incurring a lifelong risk of obstructive airway diseases such as asthma and chronic obstructive pulmonary disease. Suboptimal fetal development results in intrauterine growth restriction and low birth weight at term (an outcome distinct from preterm complications), which are associated with subsequent obstructive disease. Numerous prenatal exposures and disorders compromise fetal development and these are summarized herein. Various physiological, structural, and mechanical abnormalities may result from prenatal disruption, including changes to airway smooth muscle structure-function, goblet cell biology, airway stiffness, geometry of the bronchial tree, lung parenchymal structure and mechanics, respiratory skeletal muscle contraction, and pulmonary inflammation. The literature therefore supports the need for early life intervention to prevent or correct growth defects, which may include simple nutritional or antioxidant therapy. © 2024 American Physiological Society. Compr Physiol 14:5729-5762, 2024.

Lung injuries induced by ozone exposure in female mice: Potential roles of the gut and lung microbes

Ozone (O3) is one of the most harmful pollutants affecting health. However, the potential effects of O3 exposure on microbes in the gut-lung axis related to lung injuries remain elusive. In this study, female mice were exposed to 0-, 0.5- and 1-ppm O3 for 28 days, followed by routine blood tests, lung function tests and histopathological examination of the colon, nasal cavity and lung. Mouse faeces and lungs were collected for 16s rRNA sequencing to assess the overall microbiological profile and screen for key differential enriched microbes (DEMs). The key DEMs in faecal samples were Butyricimonas, Rikenellaceae RC9 and Escherichia-Shigella, whereas those in lung samples were DNF00809, Fluviicola, Bryobacter, Family XII AD3011 group, Sharpea, MND1 and unclassified Phycisphaeraceae. After a search in microbe-disease databases, these key DEMs were found to be associated with lung diseases such as lung neoplasms, cystic fibrosis, pneumonia, chronic obstructive pulmonary disease, respiratory distress syndrome and bronchiectasis. Subsequently, we used transcriptomic data from Gene Expression Omnibus (GEO) with exposure conditions similar to those in this study to cross-reference with Comparative Toxicogenomic Database (CTD). Il-6 and Ccl2 were identified as the key causative genes and were validated. The findings of this study suggest that exposure to O3 leads to significant changes in the microbial composition of the gut and lungs. These changes are associated with increased levels of inflammatory factors in the lungs and impaired lung function, resulting in an increased risk of lung disease. Altogether, this study provides novel insights into the role of microbes present in the gut-lung axis in O3 exposure-induced lung injury.

A life course approach to asthma and wheezing among young children caused by ozone: A prospective birth cohort in northern China

BACKGROUND

Given differences in vulnerability of children in early life, a life course approach to asthma and wheezing (AW) in young children caused by ozone (O₃) is not fully understood.

METHODS

We conducted a birth cohort in Jinan, China from 2018 to 2021 to elucidate the onset model of childhood AW due to O₃ exposure. An inverse distance weighted model was used for individual exposure assessment. The time-dependent Cox proportional-hazard model and logistic model were used to investigate the effects of O₃ exposure on AW. Principal component analysis, interaction analysis, and distributed lag model were used to analyze the life course approach.

RESULTS

The cumulative incidence rate for AW among 6501 children aged 2 was 1.4%. A high level of O₃ was related to AW (HR: 2.10, 95% CI: 1.31, 3.37). Only O₃ exposure after birth was associated with AW, with an OR of 1.82 (1.08, 3.12), after adjusting for the effect before birth. Furthermore, adjusting for other air pollutants, the HR for the individual effect of high O₃ exposure on AW was 2.44 (1.53, 3.89). Interestingly, P values for interactions for O₃ and the principal components of other pollutants, as well as the characteristic variable of open windows were less than 0.1. Moreover, an increase in the IQR of O₃ exposure at the 31st to 37th weeks before birth and the 1st to 105th weeks after birth was associated with an increase in the HRs for AW.

CONCLUSIONS

High-level of O₃ exposure after birth could lead to AW among young children. Importantly, the AW onset model may include the risk factors accumulation and the sensitive period model. Specifically, there are two sensitive windows in early life, and the correlated insults between the high level of O₃ and other pollutants as well as open windows in the asthma-inducing effect.

Prenatal Ambient Air Pollutant Mixture Exposure and Early School-age Lung Function

Research linking prenatal ambient air pollution with childhood lung function has largely considered one pollutant at a time. Real-life exposure is to mixtures of pollutants and their chemical components; not considering joint effects/effect modification by co-exposures contributes to misleading results.

Methods

Analyses included 198 mother-child dyads recruited from two hospitals and affiliated community health centers in Boston, Massachusetts, USA. Daily prenatal pollutant exposures were estimated using satellite-based hybrid chemical-transport models, including nitrogen dioxide(NO2), ozone(O3), and fine particle constituents (elemental carbon [EC], organic carbon [OC], nitrate [NO3 -], sulfate [SO4 2-], and ammonium [NH4 +]). Spirometry was performed at age 6.99 ± 0.89 years; forced expiratory volume in 1s (FEV1), forced vital capacity (FVC), and forced mid-expiratory flow (FEF25-75) z-scores accounted for age, sex, height, and race/ethnicity. We examined associations between weekly-averaged prenatal pollution mixture levels and outcomes using Bayesian Kernel Machine Regression-Distributed Lag Models (BKMR-DLMs) to identify susceptibility windows for each component and estimate a potentially complex mixture exposure-response relationship including nonlinear effects and interactions among exposures. We also performed linear regression models using time-weighted-mixture component levels derived by BKMR-DLMs adjusting for maternal age, education, perinatal smoking, and temperature.

Results

Most mothers were Hispanic (63%) or Black (21%) with ≤12 years of education (67%). BKMR-DLMs identified a significant effect for O3 exposure at 18-22 weeks gestation predicting lower FEV1/FVC. Linear regression identified significant associations for O3, NH4 +, and OC with decreased FEV1/FVC, FEV1, and FEF25-75, respectively. There was no evidence of interactions among pollutants.

Conclusions

In this multi-pollutant model, prenatal O3, OC, and NH4 + were most strongly associated with reduced early childhood lung function.