The Built Environment and Child Health: An Overview of Current Evidence

Green spaces and respiratory, cardiometabolic, and neurodevelopmental outcomes: An individual-participant data meta-analysis of >35.000 European children

Studies evaluating the benefits and risks of green spaces on children's health are scarce. The present study aimed to examine the associations between exposure to green spaces during pregnancy and early childhood with respiratory, cardiometabolic, and neurodevelopmental outcomes in school-age children. We performed an Individual-Participant Data (IPD) meta-analysis involving 35,000 children from ten European birth cohorts across eight countries. For each participant, we calculated residential Normalized Difference Vegetation Index (NDVI) within a 300 m buffer and the linear distance to green spaces (meters) during prenatal life and childhood. Multiple harmonized health outcomes were selected: asthma and wheezing, lung function, body mass index, diastolic and systolic blood pressure, non-verbal intelligence, internalizing and externalizing problems, and ADHD symptoms. We conducted a two-stage IPD meta-analysis and evaluated effect modification by socioeconomic status (SES) and sex. Between-study heterogeneity was assessed via random-effects meta-regression. Residential surrounding green spaces in childhood, not pregnancy, was associated with improved lung function, particularly higher FEV1 (β = 0.06; 95 %CI: 0.03, 0.09 I2 = 4.03 %, p < 0.001) and FVC (β = 0.07; 95 %CI: 0.04, 0.09 I2 = 0 %, p < 0.001) with a stronger association observed in females (p < 0.001). This association remained robust after multiple testing correction and did not change notably after adjusting for ambient air pollution. Increased distance to green spaces showed an association with lower FVC (β = -0.04; 95 %CI: -0.07, -0.02, I2 = 4.8, p = 0.001), with a stronger effect in children from higher SES backgrounds (p < 0.001). No consistent associations were found between green spaces and asthma, wheezing, cardiometabolic, or neurodevelopmental outcomes, with direction of effect varying across cohorts. Wheezing and neurodevelopmental outcomes showed high between-study heterogeneity, and the age at outcome assessment was only associated with heterogeneity in internalizing problems.. This large European meta-analysis suggests that childhood exposure to green spaces may lead to better lung function. Associations with other respiratory outcomes and selected cardiometabolic and neurodevelopmental outcomes remain inconclusive.

Association of Maternal Air Pollution Exposure and Infant Lung Function Is Modified by Genetic Propensity to Oxidative Stress

BACKGROUND AND OBJECTIVE

The association between air pollution and poor respiratory health outcomes is well established. Children are particularly at risk from air pollution, especially during the prenatal period as their organs and systems are still undergoing crucial development. This study investigated maternal exposure to air pollution during pregnancy and oxidative stress (OS), inflammation, and infant lung function at 4 weeks of age.

METHODS

Data from the Barwon Infant Study were available for 314 infants. The exposure to NO2 and PM2.5 were estimated. Infant lung function (4 weeks) was measured by multiple-breath washout. Glycoprotein acetyls (GlycA) (36 weeks prenatal), cord blood, and OS biomarkers were measured in maternal urine (28 weeks). A genetic pathway score for OS (gPFSox) was calculated. Linear regression was used and potential modification by the OS genotype was tested.

RESULTS

There was no relationship between maternal exposure to air pollution and infant lung function, or with GlycA or OS during pregnancy. We found an association in children with a genetic propensity to OS between NO2 and a lower functional residual capacity (FRC) (β = -5.3 mls, 95% CI (-9.3, -1.3), p = 0.01) and lung clearance index (LCI) score (β = 0.46 turnovers, (95% CI 0.10, 0.82), p = 0.01).

CONCLUSION

High prenatal exposure to ambient NO2 is associated with a lower FRC and a higher LCI score in infants with a genetic propensity to oxidative stress. There was no relationship between maternal exposure to air pollution with maternal and cord blood inflammation or OS biomarkers.

Association of exposures to environmental chemicals estimated through primary teeth biomatrix and health outcomes in children and adolescents - A systematic review

Children's heightened susceptibility to environmental exposure arises from their underdeveloped detoxification mechanisms and augmented per-unit body-weight absorption capacity for chemical compounds. Primary teeth are an emerging biomatrix, which aid in storing crucial data on early exposure to harmful substances and developmental illnesses. This systematic review aimed to evaluate the association between environmental chemical exposure and health outcomes in children and adolescents using primary teeth as a matrix. The study protocol was registered with PROSPERO (CRD42023428013). The review spanned studies published between 1974 and 2023, identified through an extensive literature search on databases like MEDLINE, EMBASE, LILACS, CINAHL, the Cochrane Oral Health Group Specialized Register, Scopus, and Web of Science. Distiller SR software was used to assess study quality and extract the outcome data. The NTP-OHAT scale assessed evidence quality, and case-control, cross-sectional, and cohort studies in English were included. Comprehensively reviewing 5287 articles resulted in 29 studies being included in the final analysis, comprising 15 cross-sectional, seven case-control, and seven cohort studies. All 29 studies qualified for qualitative analysis. Eleven studies analyzed lead (Pb) effects on health outcomes, four analyzed manganese (Mn), and 14 investigated other element groups. Primary teeth biomatrix assessed various health outcomes: neurobehavior, childhood behaviour, ADHD, birth outcomes, fetal alcohol syndrome disease, inflammatory bowel disease, and dental caries. This study contributes to existing evidence, reinforcing a link between environmental metal exposure and health consequences. The evidence extends to prenatal and postnatal periods, substantiated by primary teeth biomatrix analysis. Lead level fluctuations can influence neuropsychological functioning, potentially causing cognitive impairments. Altered manganese levels correlate with behavioral issues, adverse effects on visuospatial development, and birth weight changes. Primary teeth biomatrices aid fetal alcohol spectrum disorders diagnosis, and correlations between organo-chemical exposure and autism were observed.

The Health-Related and Learning Performance Effects of Air Pollution and Other Urban-Related Environmental Factors on School-Age Children and Adolescents-A Scoping Review of Systematic Reviews

PURPOSE OF REVIEW

This scoping review aims to assess the impact of air pollution, traffic noise, heat, and green and blue space exposures on the physical and cognitive development of school-age children and adolescents. While existing evidence indicates adverse effects of transport-related exposures on their health, a comprehensive scoping review is necessary to consolidate findings on various urban environmental exposures' effects on children's development.

RECENT FINDINGS

There is consistent evidence on how air pollution negatively affects children's cognitive and respiratory health and learning performance, increasing their susceptibility to diseases in their adult life. Scientific evidence on heat and traffic noise, while less researched, indicates that they negatively affect children's health. On the contrary, green space exposure seems to benefit or mitigate these adverse effects, suggesting a potential strategy to promote children's cognitive and physical development in urban settings. This review underscores the substantial impact of urban exposures on the physical and mental development of children and adolescents. It highlights adverse health effects that can extend into adulthood, affecting academic opportunities and well-being beyond health. While acknowledging the necessity for more research on the mechanisms of air pollution effects and associations with heat and noise exposure, the review advocates prioritizing policy changes and urban planning interventions. This includes minimizing air pollution and traffic noise while enhancing urban vegetation, particularly in school environments, to ensure the healthy development of children and promote lifelong health.

Relationships Between Measures of the Physical Activity-Related Built Environment and Excess Weight in Preschoolers: A Retrospective, Population-Level Cohort Study

Background: The built environment can impact health outcomes. Our purpose was to examine relationships between built environment variables related to physical activity and excess weight in preschoolers. Methods: In this retrospective, population-level study of 4- to 6-year-olds, anthropometric measurements were taken between 2009 and 2017 in Calgary and Edmonton, Alberta, Canada. Based on BMI z-scores (BMIz), children were classified as normal weight (-2 ≤ BMIz <1) or excess weight (BMIz ≥1; overweight and obesity). Physical activity-related built environment variables were calculated (distances to nearest playground, major park, school; street intersection density; number of playgrounds and major parks within an 800 m buffer zone). Binomial logistic regression models estimated associations between physical activity-related built environment variables and excess weight. Results: Our analysis included 140,368 participants (females: n = 69,454; Calgary: n = 84,101). For Calgary, adjusted odds ratios (aORs) showed the odds of excess weight increased 1% for every 100-intersection increase [1.010 (1.006-1.015); p < 0.0001] and 13.6% when there were ≥4 playgrounds (vs. 0 or 1) within an 800 m buffer zone [1.136 (1.037-1.243); p = 0.0059]. For Edmonton, aORs revealed lower odds of excess weight for every 100 m increase in distances between residences to nearest major park [0.991 (0.986-0.996); p = 0.0005] and school [0.992 (0.990-0.995); p < 0.0001]. The odds of excess weight decreased as the number of major parks within the 800 m buffer zone increased from 0 to 1 [0.943 (0.896-0.992); p = 0.023] and from 0 to ≥3 [0.879 (0.773-0.999); p = 0.048]. Conclusion: The physical activity-related built environment was associated with excess weight in preschoolers, although relationships varied between cities that differed demographically and geographically.

The impact of indoor air pollution on children's health and well-being: the experts' consensus

BACKGROUND

Pollution of the indoor environment represents a concern for human health, mainly in case of prolonged exposure such as in the case of women, children, the elderly, and the chronically ill, who spend most of their time in closed environments.

MAIN BODY

The aim of the study is to organize a group of experts in order to evaluate the evidence and discuss the main risk factors concerning indoor air and the impact on human health as well as challenging factors regarding preventive strategies to reduce pollution. The experts highlighted the main risk factors concerning indoor air, including poor ventilation, climatic conditions, chemical substances, and socio-economic status. They discussed the impact on human health in terms of mortality and morbidity, as well as challenging factors regarding preventive strategies to reduce pollution.

CONCLUSION

The experts identified strategies that can be reinforced to reduce indoor pollution and prevent negative consequences on human health at national and local levels.

Urban environment during pregnancy and childhood and white matter microstructure in preadolescence in two European birth cohorts

Growing evidence suggests that urban environment may influence cognition and behavior in children, but the underlying pollutant and neurobiological mechanisms are unclear. We evaluated the association of built environment and urban natural space indicators during pregnancy and childhood with brain white matter microstructure in preadolescents, and examined the potential mediating role of air pollution and road-traffic noise. We used data of the Generation R Study, a population-based birth cohort in Rotterdam, the Netherlands (n = 2725; 2002-2006) for the primary analyses. Replication of the main findings was attempted on an independent neuroimaging dataset from the PELAGIE birth cohort, France (n = 95; 2002-2006). We assessed exposures to 12 built environment and 4 urban natural spaces indicators from conception up to 9 years of age. We computed 2 white matter microstructure outcomes (i.e., average of fractional anisotropy (FA) and mean diffusivity (MD) from 12 white matte tracts) from diffusion tensor imaging data. Greater distance to the nearest major green space during pregnancy was associated with higher whole-brain FA (0.001 (95%CI 0.000; 0.002) per 7 m increase), and higher land use diversity during childhood was associated with lower whole-brain MD (-0.001 (95%CI -0.002; -0.000) per 0.12-point increase), with no evidence of mediation by air pollution nor road-traffic noise. Higher percentage of transport and lower surrounding greenness during pregnancy were associated with lower whole-brain FA, and road-traffic noise mediated 19% and 52% of these associations, respectively. We found estimates in the same direction in the PELAGIE cohort, although confidence intervals were larger and included the null. This study suggests an association between urban environment and white matter microstructure, mainly through road-traffic noise, indicating that greater access to green space nearby might promote white matter development.

Urban environment during pregnancy and lung function, wheezing, and asthma in school-age children. The generation R study

The urban environment during pregnancy may influence child's respiratory health, but scarce evidence exists on systematic evaluation of multiple urban exposures (e.g., air pollution, natural spaces, noise, built environment) on children's lung function, wheezing, and asthma development. We aimed to examine the association of the urban environment during pregnancy with lung function, preschool wheezing, and school-age asthma. We included 5624 mother-child pairs participating in a population-based prospective birth cohort. We estimated 30 urban environmental exposures including air pollution, road traffic noise, traffic, green spaces, blue spaces, and built environment during pregnancy. At 10 years of age, lung function was measured by spirometry. Information on preschool wheezing and physician-diagnosed school-age asthma was obtained from multiple questionnaires. We described single-exposure associations with respiratory outcomes using an exposome-wide association study. We also identified patterns of urban exposures with hierarchical clustering on principal components analysis and examined their associations with respiratory outcomes using multivariate regression models. Single-exposure analyses showed associations of higher particulate matter (PM) with lower mid-expiratory flow (FEF25-75%) (e.g., for PM < 2.5 μm of diameter [PM2.5] z-score = -0.06 [-0.09, -0.03]) and higher forced expiratory volume in 1s (FEV1) and forced vital capacity (FVC) (e.g., for PM2.5 FEV1 0.05 [0.02, 0.08]) after correction for multiple-hypothesis testing. Cluster analysis described three patterns of urban exposures during pregnancy and showed that the cluster characterised by higher levels of air pollution, noise, walkability, street connectivity, and lower levels of natural spaces were associated with lower FEF25-75% (-0.08 [-0.17, 0.00]), and higher odds of preschool wheezing (1.21 [1.03, 1.43]). This study shows that the characteristics of the urban environment during pregnancy are of relevance to the offspring's respiratory health during childhood.

Effect of prevalence of alcohol consumption and tobacco use in Mexican municipalities on early childhood development

One of the most critical time periods in childhood is from birth to five years of age. Children exposed to alcohol and/or tobacco via family members and neighborhood are at risk for childhood developmental delays. This study evaluated the association of early childhood development with the prevalence of alcohol consumption and tobacco use in Mexican municipalities. This is a cross-sectional study. Early childhood development information from 2,345 children aged from 36 to 59 months was obtained from the 2015 Mexican National Survey of Boys, Girls, and Women (ENIM). Data on alcohol consumption and tobacco use come from the 2016 Mexican National Survey on Drugs, Alcohol, and Tobacco Consumption (ENCODAT). Multilevel logistic models were fitted to evaluate the association of the prevalence of alcohol consumption and tobacco use with the inadequacy of early childhood development. Children living in municipalities with high prevalence of alcohol consumption (OR = 13.410; 95%CI: 2.986; 60.240) and tobacco use (OR = 15.080; 95%CI: 2.040; 111.400) were less likely to be developmentally on track regarding early childhood development after adjustment for individual variables related to the child's development and other environmental variables at municipal level. Childhood exposure to alcohol and tobacco in the neighborhood may directly contribute to inadequate early childhood development. These findings suggest that there is an urgent need to develop effective interventions aimed at reducing alcohol consumption and tobacco use in municipalities to ensure adequate early childhood development.

A systematic review on the relationship between the built environment and children's quality of life

BACKGROUND

Evidence of the effects of the built environment on children has mainly focused on disease outcomes; however, quality of life (QoL) has gained increasing attention as an important health and policy endpoint itself. Research on built environment effects on children's QoL could inform public health programs and urban planning and design.

OBJECTIVE

We aimed to review and synthesize the evidence of the relationship between built environment features and children's QoL.

METHODS

Five research databases were searched for quantitative peer-reviewed studies on children between 2 and 18 years, published in English or German between January 2010 and August 2023. Only primary research was considered. Included studies (n = 17) were coded and methodologically assessed with the Joanna Briggs Critical Appraisal Checklists, and relevant data were extracted, analyzed, and synthesized, using the following built environment framework: (1) neighborhood green and blue space, (2) neighborhood infrastructure, and (3) neighborhood perception.

RESULTS

Green space was positively associated with children's QoL. Infrastructure yielded inconclusive results across all measured aspects. Overall neighborhood satisfaction was positively correlated with higher QoL but results on perceived environmental safety were mixed.

CONCLUSIONS

Most studies are correlational, making it difficult to infer causality. While the positive findings of green space on QoL are consistent, specific features of the built environment show inconsistent results. Overall perception of the built environment, such as neighborhood satisfaction, also shows more robust results compared to perceptions of specific features of the built environment. Due to the heterogeneity of both built environment and QoL measures, consistent measures of both concepts will help advance this area of research.

Obesogenic neighborhood environment is associated with body fat and low-grade inflammation in Brazilian children: could the mother's BMI be a mediating factor?

OBJECTIVE

To evaluate the direct and indirect associations of obesogenic and leptogenic neighborhood environments with body fat, and pro- and anti-inflammatory adipokines in Brazilian children.

DESIGN

Cross-sectional study. The body fat distribution was assessed using dual-energy X-ray absorptiometry (DXA). Concentrations of leptin and adiponectin were measured. Four hundred meters (0·25 miles) road network buffer was the neighborhood unit used to assess the environmental characteristics around households. Obesogenic and leptogenic environments were the latent variables obtained from the observed characteristics. The mother's BMI, ultra-processed food consumption, and physical activity before and after school, were tested as mediating variables. A hybrid model of structural equations was used to test the direct and indirect associations of obesogenic and leptogenic environments with body fat, leptin and adiponectin concentrations.

SETTING

Urban area of Viçosa, Minas Gerais, Brazil.

PARTICIPANTS

Children aged 8- and 9-years (n 367).

RESULTS

Obesogenic environment was directly associated with the mother's BMI (β: 0·24, P = 0·02) and the child's body fat (β: 0·19, P = 0·02). The mother's BMI and body fat mediated the association of the obesogenic environment with leptin concentrations (β: 0·05, P = 0·02).

CONCLUSIONS

Obesogenic neighborhood environment was directly associated with body fat and mother's BMI, and indirectly associated with leptin concentrations in Brazilian children, mediated by the mother's BMI and body fat.

Characteristics of the obesogenic environment around schools are associated with body fat and low-grade inflammation in Brazilian children

OBJECTIVE

To assess the association of obesogenic environmental characteristics around schools with body adiposity and adipokine concentrations in Brazilian children.

DESIGN

Cross-sectional study. Body adiposity was assessed using the dual-energy X-ray absorptiometry. Concentrations of leptin, adiponectin, retinol-binding protein 4 (RBP4) and chemerin were measured. Predominantly ultra-processed food (UPF) stores, public physical activity (PA) facilities, green spaces, walkability, traffic accidents and crime were evaluated. The neighbourhood unit was the 400 m (0·25 miles) road network buffer around schools. The association of environmental characteristics with body adiposity and adipokine concentrations was assessed by linear regression models using generalised estimating equations.

SETTING

Urban schools (n 24), Viçosa, Minas Gerais, Brazil.

PARTICIPANTS

Children aged 8 and 9 years (n 378).

RESULTS

A higher density of predominantly UPF stores and a lower percentage of green space were associated with higher total (β: 0·12; 95 % CI 0·06, 0·18 and β: -0·10; 95 % CI -0·16, -0·04, respectively) and android body fat (β: 0·28; 95 % CI 0·13, 0·43 and β: -0·18; 95 % CI -0·32, -0·04, respectively). In addition, the densities of PA facilities and crime were inversely associated with leptin concentrations. Traffic accidents density and percentage of green spaces around schools had, respectively, a positive and an inverse association with concentrations of adiponectin and RBP4.

CONCLUSIONS

Obesogenic environmental characteristics around schools were associated with total and android body fat, as well as with pro-inflammatory adipokine concentrations in Brazilian children from a medium-sized city.

Air pollution and fecundability in a North American preconception cohort study

BACKGROUND

Animal and epidemiologic studies indicate that air pollution may adversely affect fertility. However, the level of evidence is limited and specific pollutants driving the association are inconsistent across studies.

METHODS

We used data from a web-based preconception cohort study of pregnancy planners enrolled during 2013-2019 (Pregnancy Study Online; PRESTO). Eligible participants self-identified as female, were aged 21-45 years, resided in the United States (U.S.) or Canada, and were trying to conceive without fertility treatments. Participants completed a baseline questionnaire and bi-monthly follow-up questionnaires until conception or 12 months. We analyzed data from 8,747 participants (U.S.: 7,304; Canada: 1,443) who had been trying to conceive for < 12 cycles at enrollment. We estimated residential ambient concentrations of particulate matter < 2.5 µm (PM2.5), nitrogen dioxide (NO2), and ozone (O3) using validated spatiotemporal models specific to each country. We fit country-specific proportional probabilities regression models to estimate the association between annual average, menstrual cycle-specific, and preconception average pollutant concentrations with fecundability, the per-cycle probability of conception. We calculated fecundability ratios (FRs) and 95% confidence intervals (CIs) and adjusted for individual- and neighborhood-level confounders.

RESULTS

In the U.S., the FRs for a 5-µg/m3 increase in annual average, cycle-specific, and preconception average PM2.5 concentrations were 0.94 (95% CI: 0.83, 1.08), 1.00 (95% CI: 0.93, 1.07), and 1.00 (95% CI: 0.93, 1.09), respectively. In Canada, the corresponding FRs were 0.92 (95% CI: 0.74, 1.16), 0.97 (95% CI: 0.87, 1.09), and 0.94 (95% CI: 0.80, 1.09), respectively. Likewise, NO2 and O3 concentrations were not strongly associated with fecundability in either country.

CONCLUSIONS

Neither annual average, menstrual cycle-specific, nor preconception average exposure to ambient PM2.5, NO2, and O3 were appreciably associated with reduced fecundability in this cohort of pregnancy planners.

Association of maternal air pollution exposure and infant lung function is modified by genetic propensity to oxidative stress

Introduction

The association between air pollution and poor respiratory health outcomes is well established, however less is known about the biological mechanisms, especially in early life. Children are particularly at risk from air pollution, especially during the prenatal period as their organs and systems are still undergoing crucial development. Therefore, our study aims to investigate if maternal exposure to air pollution during pregnancy is associated with oxidative stress (OS) and inflammation in pregnancy or infant lung function at 4 weeks of age, and the extent to which the association is modified by an infant's genetic risk of OS.

Methods

The Barwon Infant Study (BIS) is a longitudinal study of Australian children from the region of Geelong, Victoria. A total of 314 infants had available lung function and maternal OS markers. Exposure to annual air pollutants (NO 2 and PM 2.5 ) were estimated using validated, satellite-based, land-use regression models. Infant lung function was measured by multiple-breath washout, and the ratio of peak tidal expiratory flow over expiratory time was calculated at 4 weeks of age. An inflammation biomarker, glycoprotein acetyls (GlycA), was measured in maternal (36 weeks) and cord blood, and oxidative stress (OS) biomarkers, 8-hydroxyguanine (8-OHGua) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured in maternal urine at 28 weeks. A genetic pathway score for OS (gPFS ox ) was calculated for each infant participant in the BIS cohort, and high risk defined as score >8. Linear regression was used to explore the association of maternal air pollution exposure with infant lung function, and potential modification by OS genotype was tested through use of interaction terms and other methods.

Results

There was no evidence of a relationship between maternal exposure to air pollution and infant lung function in the whole population. We did not find an association between air pollution and GlycA or OS during pregnancy. We found evidence of an association between NO 2 and lower in functional residual capacity (FRC) for children with a high genetic risk of OS (β=-5.3 mls, 95% CI (-9.3, -1.3), p=0.01). We also found that when NO 2 was considered in tertiles, the highest tertile of NO 2 was associated with increase in lung clearance index (LCI) (β=0.46 turnovers, (95% CI 0.10, 0.82), p=0.01) in children with a genetic propensity to OS.

Conclusion

Our study found that high prenatal levels of exposure to ambient NO 2 levels is associated with lower FRC and higher LCI in infants with a genetic propensity to oxidative stress. There was no relationship between maternal exposure to air pollution with maternal and cord blood inflammation or OS biomarkers.

Availability, accessibility, and use of green spaces and cognitive development in primary school children

Green spaces may have beneficial impacts on children's cognition. However, few studies explored the exposure to green spaces beyond residential areas, and their availability, accessibility and uses at the same time. The aim of the present study was to describe patterns of availability, accessibility, and uses of green spaces among primary school children and to explore how these exposure dimensions are associated with cognitive development. Exposures to green space near home, school, commuting route, and other daily activity locations were assessed for 1607 children aged 6-11 years from six birth cohorts across Europe, and included variables related to: availability (NDVI buffers: 100, 300, 500 m), potential accessibility (proximity to a major green space: linear distance; within 300 m), and use (play time in green spaces: hours/year), and the number of visits to green spaces (times/previous week). Cognition measured as fluid intelligence, inattention, and working memory was assessed by computerized tests. We performed multiple linear regression analyses on pooled and imputed data adjusted for individual and area-level confounders. Availability, accessibility, and uses of green spaces showed a social gradient that was unfavorable in more vulnerable socioeconomic groups. NDVI was associated with more playing time in green spaces, but proximity to a major green space was not. Associations between green space exposures and cognitive function outcomes were not statistically significant in our overall study population. Stratification by socioeconomic variables showed that living within 300 m of a major green space was associated with improved working memory only in children in less deprived residential areas (β = 0.30, CI: 0.09,0.51), and that more time playing in green spaces was associated with better working memory only in children of highly educated mothers (β per IQR increase in hour/year = 0.10; 95% CI: 0.01, 0.19). However, studying within 300 m of a major green space increased inattention scores in children in more deprived areas (β = 15.45, 95% CI: 3.50, 27.40).

Environment and child well-being: A scoping review of reviews to guide policies

Background

Acting on social determinants is the most effective, efficient, and fairest strategy to improve population health and health equity. Because of their vulnerability and dependence, children are particularly exposed to the deleterious effects of their living environment. Taking these issues into account in the development of public policies and identifying levers for action are crucial. The objective of this scoping review of reviews is to identify the main environmental determinants on children's health and development, and their mechanisms of effect, to be addressed by public policies.

Methods

We conducted a scoping review of reviews in accordance with the method developed by Arksey and O'Malley, and Levac and colleagues' methodology advancement and the PRISMA guideline. Inclusion criteria were identified with the PICos (population-phenomena of interest-context-study design) framework. We used the PubMed database and conducted a thematic analyze.

Results

Forty-seven articles were selected. Their analysis allowed us to identify five categories of interdependent environmental determinants of child health: i) urban design ii) contaminants, iii) parenting environment, iv) social conditions, v) climate change. Together and in a systemic way, they act on the health of the child.

Conclusion

The review carried out allows us to propose a pragmatic framework for clarifying the effects of the physical, social, and economic environment on children's health and wellbeing.

An Overview of How the Built Environment Relates to Children's Health

PURPOSE OF REVIEW

Explore the varied pathways between the built environment and children's health. The review begins by describing how the built environment and transport infrastructure relate to conditions that lead to health outcomes. The review examines emissions, noise, and traffic dangers in relation to children's physical, mental, and social health.

RECENT FINDINGS

Evidence is increasing for walkable neighborhoods and health-related behavior such as physical activity. However, diverse land uses (often supporting walkability) were also found to increase traffic injuries. Cognitive impacts of motorways on children at schools were found. Finally, the relationships between social activities and built environment are beginning. The built environment's influence on various physical health outcomes is increasingly clear and is often through a transport pathway. However, the links with mental and social health are less developed, though recent findings show significant results. Having accessible child-relevant destinations is an important consideration for children's health.

A systematic review on the relationship between the built environment and children's quality of life

Background

Evidence of the effects of the built environment on children has mainly focused on disease outcomes; however, quality of life (QoL) has gained increasing attention as an important health and policy endpoint itself. Research on built environment effects on children's QoL could inform public health programs and urban planning and design.

Objective

We aimed to review and synthesize the evidence of the relationship between built environment features and children's QoL.

Methods

Five research databases were searched for quantitative peer-reviewed studies on children between 2-18 years, published in English or German between 2010-2021. Only primary research was considered. Included studies (n=17) were coded and methodologically assessed with the Joanna Briggs Critical Appraisal Checklists, and relevant data were extracted, analyzed, and synthesized, using the following built environment thematic framework: 1) neighborhood natural environment, 2) neighborhood infrastructure, and 3) neighborhood perception.

Results

Green space was positively associated with children's QoL. Infrastructure yielded inconclusive results across all measured aspects. Overall neighborhood satisfaction was positively correlated with higher QoL but results on perceived environmental safety were mixed.

Conclusions

Most studies are correlational, making it difficult to infer causality. While the positive findings of green space on QoL are consistent, specific features of the built environment show inconsistent results. Overall perception of the built environment, such as neighborhood satisfaction, also shows more robust results compared to perceptions of specific features of the built environment. Due to the heterogeneity of both built environment and QoL measures, consistent definitions of both concepts will help advance this area of research.

Obesogenic environment around schools is associated with atherogenic risk in Brazilian children

INTRODUCTION

Cardiometabolic risk factors often emerge in childhood, increasing the risk of cardiovascular diseases in adulthood. The school environments represent an important active space in a child's routine and may influence their health status.

METHODS

In this cross-sectional study, we aimed to evaluate the clustering of cardiometabolic risk factors and its association with the obesogenic and leptogenic environment around schools. A total of 378 children (181 boys; 197 girls) aged 8 and 9 years, enrolled in all urban schools of Viçosa, Minas Gerais, Brazil, were evaluated. Concentrations of high-density lipoprotein-cholesterol (HDL-c) and triglycerides (TG), and the insulin resistance (HOMA-IR), waist circumference (WC), and mean arterial pressure (MAP) were measured. The neighborhood income, walkability index, predominantly ultra-processed food stores, public spaces for leisure and/or physical activities, traffic accidents, crime and green spaces densities were assessed in 400 road network buffers around schools. To test association of the obesogenic and leptogenic environment around schools with cardiometabolic risk clustering, binary logistic regression models were performed with generalized estimating equations.

RESULTS

"Obesogenic school environments" had greater densities of ultra-processed food stores, crime and traffic accidents, and higher walkability. The "↓ Atherogenic risk" cluster consisted of higher HDL-c values. There was an inverse association between the obesogenic environment around schools and a child's "↓ atherogenic risk" clustering (OR = 0.63; p < 0.001).

CONCLUSION

We concluded that public policies aimed at modifying the environment around schools, by providing healthier food options and safe conditions for active mobility, are essential to prevent child's atherogenic risk.

Neighborhood obesogenic environment and cardiometabolic risk in Brazilian children: The mediation role of the mother's body mass index

OBJECTIVE

We aimed to evaluate the association of neighborhood obesogenic and leptogenic environments with cardiometabolic risk clustering among Brazilian schoolchildren, mediated by child's ultra-processed food consumption and the mother's body mass index (BMI).

METHODS

A total of 367 children aged 8-9 years, enrolled in urban schools of Viçosa, Minas Gerais, Brazil, were evaluated. Waist circumference, insulin resistance, blood pressure, high-density lipoprotein-cholesterol, and triglycerides concentrations were measured. The child's ultra-processed food consumption assessment was performed by applying three 24-hour dietary recall. The mother's weight and height values were used to calculate the BMI. The neighborhood income, walkability index, predominantly ultra-processed food stores, public spaces for leisure, and/or physical activities, traffic accidents, crime, and green spaces densities were assessed in four hundred road network buffers around households. From neighborhood and cardiometabolic risk variables, four latent variables were obtained from confirmatory factor analysis: neighborhood "obesogenic", and "leptogenic" environments; "high cardiometabolic risk," and "low atherogenic risk". A structural equation model was used to test the direct and indirect associations between neighborhood environment and cardiometabolic risk clusters.

RESULTS

The neighborhood obesogenic environment had a significant total association (Standardized Coefficient = 0.172, p = .011) and was indirectly associated with the child's "high cardiometabolic risk" cluster, mediated by the mother's body mass index (Standardized Coefficient = 0.066, p = .049).

CONCLUSIONS

Our results reinforce the role of the urban environment on maternal obesity and child's cardiometabolic risk and provide evidence for public health policies aimed to prevent such conditions.

Food and Physical Activity Environment in the US-Affiliated Pacific Region: The Children's Healthy Living Program

OBJECTIVE

To describe the quality of food and physical activity (PA) environments by World Bank Income level in jurisdictions from the Children's Healthy Living Program.

DESIGN

Baseline cross-sectional community data were analyzed from 11 jurisdictions categorized by World Bank Income levels to describe exposure to different food and PA outlets. The Children's Healthy Living Program was a multilevel, multijurisdictional prevalence study and community intervention trial that reduced child obesity in the US-Affiliated Pacific region.

SETTING

US-Affiliated Pacific region.

PARTICIPANTS

Food (n = 426) and PA (n = 552) Outlets.

MAIN OUTCOME MEASURES

Physical activity and food scores that reflect the quality of the outlets that support being physically active and healthy eating options, respectively.

ANALYSIS

Descriptive statistics are presented as means ± SD or percentages.

RESULTS

High-income-income level jurisdictions had higher food and PA scores than middle-income level jurisdictions.

CONCLUSIONS AND IMPLICATIONS

The US-Affiliated Pacific region has limited quality food and PA outlets in underserved communities at risk for obesity. The findings in this paper can be used to develop tools and design interventions to improve the food and PA environment to increase a healthier, active lifestyle.

Inflammation and the Potential Implication of Macrophage-Microglia Polarization in Human ASD: An Overview

Autism spectrum disorder (ASD) is a heterogeneous collection of neurodevelopmental disorders, difficult to diagnose and currently lacking treatment options. The possibility of finding reliable biomarkers useful for early identification would offer the opportunity to intervene with treatment strategies to improve the life quality of ASD patients. To date, there are many recognized risk factors for the development of ASD, both genetic and non-genetic. Although genetic and epigenetic factors may play a critical role, the extent of their contribution to ASD risk is still under study. On the other hand, non-genetic risk factors include pollution, nutrition, infection, psychological states, and lifestyle, all together known as the exposome, which impacts the mother's and fetus's life, especially during pregnancy. Pathogenic and non-pathogenic maternal immune activation (MIA) and autoimmune diseases can cause various alterations in the fetal environment, also contributing to the etiology of ASD in offspring. Activation of monocytes, macrophages, mast cells and microglia and high production of pro-inflammatory cytokines are indeed the cause of neuroinflammation, and the latter is involved in ASD's onset and development. In this review, we focused on non-genetic risk factors, especially on the connection between inflammation, macrophage polarization and ASD syndrome, MIA, and the involvement of microglia.

Urban Air Pollution and Greenness in Relation to Public Health

Background

Air pollution is the result of economic growth and urbanization. Air pollution has been progressively recognized as a serious problem for cities, through widespread effects on health and well-being. There is less concern from stakeholders about greenness and air pollution mitigating factors in an urban area. This research targeted to indicate the spatial dissemination of greenery, air quality levels (PM_2.5, PM₁₀, CO₂, and AQI), and exposure to air quality-related health risks for the people in the urban area.

Method

The data were collected by measuring air quality at transportation stations and manufacturing industries with Air visual pro, then observing and mapping greenness in the city within the administrative boundary by GIS (street greenery, forest, availability of greenness in the manufacturing industry), and lastly questionnaire and interview were employed for air quality-related health issues. Then, the air quality data were analyzed by using USAQI standards and health messages. Both quantitative and qualitative research approach had employed to explore air pollution levels, availability of greenness, and air quality-related health issues. Moreover, Health questionnaires and greenness were correlated with air quality levels by a simple linear regression model.

Result

The result indicated that there was unhealthy air quality in the transportation and manufacturing industries. The measured air quality showed in a range of 50.13-96.84 μg/m³ of PM_2.5, 645-1764 ppm of CO_2, and 137-179 Air quality index (AQI). The highest mean of PM_2.5 and air quality concentrations at Addis Ababa transportation stations and manufacturing sites ranged between 63.46 and 104.45 μg/m³ and 179-326, respectively. It was observed with less street greenery and greenness available in residential, commercial areas, and manufacturing industries. The pollution level was beyond the limit of WHO standards. The result has shown a health risk to the public in the city, particularly for drivers, street vendors, and manufacturing industry employees. Among 480 respondents, 57.92% experienced health risks due to air pollution by medical evidence.

Conclusion

High health risks due to industries and old motor vehicles in the city need to be reduced by introducing policies and strategies for low-carbon, minimizing traveling distance, encouraging high occupancy vehicles, and promoting a green legacy in the street network and green building.

School-Based Interventions to Support Healthy Indoor and Outdoor Environments for Children: A Systematic Review

Environmental exposures are associated with children's health. Schools are often urban exposure 'hotspots' for pollution, noise, lack of green space and un-walkable built environments. The aim of this systematic review was to explore the impact of school-based interventions on the modification of indoor and outdoor stressors related to the built and natural environment on children's exposure and health. A systematic review of seven databases was performed. We included quantitative studies on children aged 5-12, which reported intervention delivered within school settings aimed at addressing key environmental exposures including air pollution, green spaces, traffic noise or active travel; and reported physical and mental health, physical activity or active travel behavior. The quality of studies was assessed and interventions were described using a standardized framework. A narrative synthesis approach was used to describe the findings. Thirty-nine papers were included on three main intervention types: improve indoor air quality by the increase of ventilation rates in classrooms; increase children's green time or greening schools, and multicomponent interventions to increase active travel to school by changes in pedestrian facilities. No eligible intervention to reduce traffic noise at school was found. Increasing ventilation rates improved short-term indoor air quality in classrooms, but the effect on cognitive performance was inconsistent. Greening schools and increasing children's green time have consistent positive effects on cognition and physical activity, but not in behavior. Multi-component interventions can increase walking and cycling after three years. Overall, the studies were rated as having poor quality owing to weak study designs. We found modest evidence that school-based built and natural environment interventions can improve children's exposure and health.

The influence of outdoor play spaces in urban parks on children's social anxiety

Urban green spaces are critical to the healthy development of children's social interactions and activities. However, the relationship between urban green spaces for children's activities and the alleviation of children's social anxiety remains unclear. In this study, we aimed to explore the link between spatial characteristics and social anxiety in children. To explore the coupling relationships among green space, play space, and social anxiety, an assessment of children's play spaces and levels of social anxiety was performed using self-reported data, OpenStreetMap captured the characteristic indicators of urban parks, and the ArcGIS and SPSS softwares were used for the mathematical analysis. The results showed that (1) both the NDVI and 10-min accessibility were significantly negatively related to children's social anxiety; (2) the diversity of service facilities, surfacing materials, and the attractiveness and challenge of the environment were negatively related to children's social anxiety; (3) there were significant differences between activity types and social anxiety. These results provide design references and a theoretical basis for improving the benefits of urban green space on children's health and wellbeing.

Residential Proximity to Urban Play Spaces and Childhood Overweight and Obesity in Barcelona, Spain: A Population-Based Longitudinal Study

Findings on the relationship between play spaces and childhood overweight and obesity are mixed and scarce. This study aimed to investigate the associations between residential proximity to play spaces and the risk of childhood overweight or obesity and potential effect modifiers. This longitudinal study included children living in the city of Barcelona identified in an electronic primary healthcare record database between 2011 and 2018 (N = 75,608). Overweight and obesity were defined according to the WHO standards and we used 300 m network buffers to assess residential proximity to play spaces. We calculated the risk of developing overweight or obesity using Cox proportional hazard models. A share of 29.4% of the study population developed overweight or obesity, but we did not find consistent associations between play space indicators and overweight or obesity. We did not find any consistent sign of effect modification by sex, and only some indications of the modifying role of area socioeconomic status and level of exposure. Although it is not possible to draw clear conclusions from our study, we call for cities to continue increasing and improving urban play spaces with an equitable, healthy, and child-friendly perspective.

Not built for families: Associations between neighborhood disinvestment and reduced parental cognitive stimulation

Infants learn and develop within an ecological context that includes family, peers, and broader built and social environments. This development relies on proximal processes—reciprocal interactions between infants and the people and environments around them that help them understand their world. Most research examining predictors of proximal processes like parent-child interaction and parenting has focused on elements within the home and family. However, factors like the neighborhood built environment may also exhibit an influence, and may be particularly critical in infancy, as socioeconomic disparities in cognition and language emerge early in life. Moreover, influence from the built environment could independently exacerbate these disparities, as research indicates that neighborhood impacts may be especially relevant for families living in neighborhoods that have experienced disinvestment and therefore have been under-resourced. The current study examines these questions by determining the association of neighborhood vacancy rate and observed physical disorder—indicators of poverty, residential stability, and long-term structural discrimination—with parental cognitive stimulation among predominantly Black/African-American families in Flint, Michigan. Flint is particularly salient for this study because vacancy rates and disinvestment vary widely across the city, driven by its long-time status as a city struggling economically. Regression analyses controlling for caregiver education, mental health, and social support indicated that vacancy rate and physical disorder negatively predicted parental cognitive stimulation. Moreover, there were significant interactions between the built environment and social support, indicating that, particularly for parent-child shared reading, vacancy rate and physical disorder predicted reduced shared reading only when parents had limited social support. These results have important implications for public policy around vacant property demolition and neighborhood reinvestment programs, as they indicate that the neighborhood built environment is associated with parenting behaviors that have important impacts on infants’ learning and development.

Association of built environment constructs and physical activity among children and adolescents in Africa: a systematic review and meta-analysis

OBJECTIVE

The objective of this review was to synthesize the association between built environment constructs and physical activity among children and adolescents in Africa.

INTRODUCTION

Previous reviews have found that several built environment constructs, such as residential density, crime safety, and availability of physical activity facilities and infrastructure, are associated with physical activity in children and adolescents; however, these reviews have tended to focus on non-African countries. Therefore, this systematic review synthesized the association between the built environment and physical activity among children and adolescents in Africa.

INCLUSION CRITERIA

This systematic review included comparative observational studies that assessed the relationship between built environmental constructs and physical activity among children and adolescents (between the ages of 5 and 19 years) in Africa.

METHODS

Comprehensive electronic searches of MEDLINE, Embase, CINAHL, Web of Science, PsycINFO, Scopus, SPORTDiscus, EThOS, and ProQuest Dissertations and Theses from inception to October 22, 2021, were conducted to identify relevant published and unpublished studies. Two reviewers independently screened papers, assessed the quality of the included studies using the JBI standard critical appraisal tool, and extracted data using a pre-piloted form. Where possible, data were synthesized using random effects meta-analyses, with effect sizes reported as mean differences (MDs) with 95% confidence intervals (CIs). The Grading of Recommendations Assessment, Development and Evaluations (GRADE) was used to assess the certainty of the findings.

RESULTS

Of the 10,706 identified records, six cross-sectional studies were included, which comprised 4628 children and adolescents. Three of the studies had a high-quality score of 7 or 8 out of 8. Seven built environment constructs were reported within the included studies, namely, residential density, street connectivity, crime safety, availability of physical activity facilities and infrastructure, walkability, esthetics, and traffic safety. Three of the constructs were assessed with objective measures. Results from individual studies found significant associations between physical activity and objective measure of traffic safety (MD 2.63 minutes per day; 95% CI 0.16 to 5.1; one study) and an objective measure of crime safety (MD 2.72 minutes per day; 95% CI 0.07 to 5.37; one study). No significant associations were found between active transportation and any of the built environment constructs. The GRADE evidence for all of the assessed constructs was either low (the built environment constructs may lead to little or no difference in physical activity or active transportation) or very low (it was uncertain whether the built environment constructs affect physical activity).

CONCLUSION

In African settings, the evidence base for the association between built environment constructs and physical activity is limited, with no consistent evidence of an association. Therefore, further high-quality studies should be conducted before firm conclusions can be drawn.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42019133324.

Physical Activity and Food Environments in and around Schools: A Case Study in Regional North-West Tasmania

A better understanding of the physical activity (PA) infrastructure in schools, the walkability of neighborhoods close to schools, and the food environments around schools, particularly in rural, socioeconomically challenged areas such as the North-West (NW) of Tasmania, could be important in the wider effort to improve the health of school-age children. Accordingly, this research aimed to assess PA resources, walkability, and food environments in and around schools in three socioeconomically disadvantaged, regional/rural Local Government Areas (LGAs) of Tasmania, Australia. A census of schools (including assessment of the PA infrastructure quality within school grounds), a walkability assessment, and a census of food outlets surrounding schools (through geospatial mapping) were executed. Most of the schools in the study region had access to an oval, basketball/volleyball/netball court, and free-standing exercise equipment. In all instances (i.e., regardless of school type), the quality of the available infrastructure was substantially higher than the number of incivilities observed. Most schools also had good (i.e., within the first four deciles) walkability. Numerous food outlets were within the walking zones of all schools in the study region, with an abundance of food outlets that predominantly sold processed unhealthy food.

Data to Decisions: Methods to Create Neighbourhood Built Environment Indicators Relevant for Early Childhood Development

Healthy development in the early years lays the foundations for children’s ongoing physical, emotional, and social development. Children develop in multiple contexts, including their local neighbourhood. Neighbourhood-built environment characteristics, such as housing, walkability, traffic exposure, availability of services, facilities, and parks, are associated with a range of health and wellbeing outcomes across the life course, but evidence with early years’ outcomes is still emerging. Data linkage techniques were used to assemble a dataset of spatial (objectively-measured) neighbourhood-built environment (BE) measures linked to participant addresses in the 2015 Australian Early Development Census (AEDC) for children living in the 21 most populous urban and regional Australian cities (n = 235,655) to help address this gap. This paper describes the methods used to develop this dataset. This linked dataset (AEDC-BE) is the first of its kind worldwide, enabling opportunities for identifying which features of the built environment are associated with ECD across Australia at scale, allow comparisons between diverse contexts, and the identification of where best to intervene. National data coverage provides statistical power to model real-world complexities, such as differences by city, state/territory, and remoteness. The neighbourhood-built environment can be modified by policy and practice at scale, and has been identified as a way to help reduce inequitable early childhood development outcomes.

Defining the Exposome Using Popular Education and Concept Mapping With Communities in Atlanta, Georgia

Introduction

The exposome concept provides a framework to better incorporate the environment into the study of health and disease and has been defined by academics to encompass all lifetime exposures including toxicants, diet, and lifestyle choices. However, initial applications of the exposome concept have been less apt at measuring social determinants of health, focusing primarily on conventional environmental exposures and lifestyle choices that do not reflect the complex lived experience of many communities. To bring community voice into the exposome concept, the HERCULES Exposome Research Center and its Stakeholder Advisory Board co-developed the Exposome Roadshow. We present and discuss the resulting community-exposome definition to inform and improve exposome research.

Materials and Methods

Four communities from distinct areas across metro-Atlanta participated in separate 2-day Exposome Roadshow workshops with concept mapping. Aligned with a popular education approach in which community knowledge is used to work collectively for change, concept mapping provided a systematic method to collect and visualize community members' knowledge and create a shared understanding to take action. Community members brainstormed, sorted, and rated their responses to the prompt: "What in your environment is affecting your and your community's health?" Responses were analyzed and visually depicted by concept maps consisting of separate but interrelated clusters of ideas. Community members discussed and validated the maps, selecting a final map illustrating their community's exposome.

Results

A total of 118 community members completed concept mapping. On average communities identified 7 clusters to define their exposome. The resulting concept maps offer a community definition of the exposome. Five major themes arose across all four communities: conventional environmental concerns, built environment, social relationships, crime and safety, and individual health and behaviors.

Discussion

The resulting community-exposome definition demonstrates the importance of expanding the scope of exposures beyond traditional environmental influences to include the lived experience of individuals and communities. While newer exposome definitions align more closely with this community definition, traditional exposome methods do not routinely include these factors. To truly capture the totality of lifetime exposures and improve human health, researchers should incorporate community perspectives into exposome research.

Multi-use physical activity trails in an urban setting and cardiovascular disease: a difference-in-differences analysis of a natural experiment in Winnipeg, Manitoba, Canada

Objective

To determine if expansion of multi-use physical activity trails in an urban centre is associated with reduced rates of cardiovascular disease (CVD).

Methods

This was a natural experiment with a difference in differences analysis using administrative health records and trail-based cycling data in Winnipeg, Canada. Prior to the intervention, each year, 314,595 (IQR: 309,044 to 319,860) persons over 30 years without CVD were in the comparison group and 37,901 residents (IQR: 37,213 to 38,488) were in the intervention group. Following the intervention, each year, 303,853 (IQR: 302,843 to 304,465) persons were in the comparison group and 35,778 (IQR: 35,551 to 36,053) in the intervention group. The natural experiment was the construction of four multi-use trails, 4-7 km in length, between 2010 and 2012. Intervention and comparison areas were based on buffers of 400 m, 800 m and 1200 m from a new multi-use trail. Bicycle counts were obtained from electromagnetic counters embedded in the trail. The primary outcome was a composite of incident CVD events: CVD-related mortality, ischemic heart disease, cerebrovascular events and congestive heart failure. The secondary outcome was a composite of incident CVD risk factors: hypertension, diabetes and dyslipidemia.

Results

Between 2014 and 2018, 1,681,125 cyclists were recorded on the trails, which varied ~ 2.0-fold across the four trails (2358 vs 4264 counts/week in summer months). Between 2000 and 2018, there were 82,632 CVD events and 201,058 CVD risk events. In propensity score matched Poisson regression models, the incident rate ratio (IRR) was 1.06 (95% CI: 0.90 to 1.24) for CVD events and 0.95 (95%CI: 0.88 to 1.02) for CVD risk factors for areas within 400 m of a trail, relative to comparison areas. Sensitivity analyses indicated this effect was greatest among households adjacent to the trail with highest cycling counts (IRR = 0.85; 95% CI: 0.75 to 0.96).

Conclusions

The addition of multi-use trails was not associated with differences in CVD events or CVD risk factors, however the differences in CVD risk may depend on the level of trail use.

Trial registration

Trial registration number: NCT04057417.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01279-z.

Dysbiosis in Inflammatory Bowel Disease: Pathogenic Role and Potential Therapeutic Targets

Microbe-host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets.

Urban environment and cognitive and motor function in children from four European birth cohorts

BACKGROUND

The urban environment may influence neurodevelopment from conception onwards, but there is no evaluation of the impact of multiple groups of exposures simultaneously. We investigated the association between early-life urban environment and cognitive and motor function in children.

METHODS

We used data from 5403 mother-child pairs from four population-based birth-cohorts (UK, France, Spain, and Greece). We estimated thirteen urban home exposures during pregnancy and childhood, including: built environment, natural spaces, and air pollution. Verbal, non-verbal, gross motor, and fine motor functions were assessed using validated tests at five years old. We ran adjusted multi-exposure models using the Deletion-Substitution-Addition algorithm.

RESULTS

Higher greenness exposure within 300 m during pregnancy was associated with higher verbal abilities (1.5 points (95% confidence interval 0.4, 2.7) per 0.20 unit increase in greenness). Higher connectivity density within 100 m and land use diversity during pregnancy were related to lower verbal abilities. Childhood exposure to PM2.5 mediated 74% of the association between greenness during childhood and verbal abilities. Higher exposure to PM2.5 during pregnancy was related to lower fine motor function (-1.2 points (-2.1, -0.4) per 3.2 μg/m3 increase in PM2.5). No associations were found with non-verbal abilities and gross motor function.

DISCUSSION

This study suggests that built environment, greenness, and air pollution may impact child cognitive and motor function at five years old. This study adds evidence that well-designed urban planning may benefit children's cognitive and motor development.

Early childhood development and urban environment in Mexico

BACKGROUND

Childhood is considered the most important phase of human development; within it the period from birth to 5 years of age is particularly critical, given the speed at which changes occur. The context where children live can influence early childhood developmnent (ECD) by providing or limiting opportunities to learn, play and establish social interactions. This study explored the associations between characteristics of the urban environment and ECD in 2,194 children aged 36 to 59 months living in urban municipalities in Mexico.

METHODS

We obtained ECD information from the 2015 Survey of Boys, Girls, and Women (ENIM, for its Spanish acronym), measured with the Early Childhood Development Index. The urban environment was evaluated at the municipal level, considering variables from five environment domains: physical, social, service, socioeconomic, and governance. Multilevel logistic models were fitted to assess the association between urban environment characteristics and the inadequacy of ECD in general and by specific development domains: learning, socio-emotional, physical, and alpha-numeric.

RESULTS

Inadequate ECD was inversely associated with the availability of libraries (OR = 0.55, 95% CI: 0.43, 0.72), and positively associated with population density (OR = 1.01, 95% CI: 1.01-1.02). For the specific ECD domains, inadequate socio-emotional development was inversely associated with the availability of libraries (OR = 0.66, 95% CI: 0.51, 0.85). Inadequate literacy-numeracy knowledge was associated inversely with the availability of daycare centers (OR = 0.56, 95% CI: 0.32, 0.97), and directly associated with the number of hospitals and clinics (OR = 1.87, 95% CI: 1.29, 2.72). Finally, the marginalization index was positively associated with inadequacy in the learning domain (OR = 1.80, 95% CI: 1.06, 3.03).

CONCLUSIONS

Some aspects of the urban environment associated with ECD, suggest that intervening in the urban context could improve overall child development. Investment in resources oriented to improve socio-emotional development and literacy (such as libraries and daycare), could foster ECD in Mexico.

Urban environment and obesity and weight-related behaviours in primary school children

BACKGROUND

Urban environments are characterised by many factors that may influence children's lifestyle and increase the risk of childhood obesity, but multiple urban exposures have scarcely been studied.

OBJECTIVE

We evaluated the association between multiple urban exposures and childhood obesity outcomes and weight-related behaviours.

METHODS

We conducted a cross-sectional study including 2213 children aged 9-12 years in Sabadell, Spain. We estimated ambient air pollution, green spaces, built and food environment, road traffic and road traffic noise at residential addresses through a total of 28 exposure variables in various buffers. Childhood obesity outcomes included body mass index (BMI), waist circumference and body fat. Weight-related behaviours included diet (fast food and sugar-sweetened beverage consumption), physical activity, sedentary behaviour, sleep duration and well-being. Associations between exposures (urban environment) and outcomes (obesity and behaviours) were estimated in single and multiple-exposure regression models and in a hierarchical clustering on principal components (HCPC) analysis.

RESULTS

Forty percent of children were overweight or obese. In single exposure models, very few associations were observed between the urban exposures and obesity outcomes or weight-related behaviours after correction for multiple testing. In multiple exposure models, PM_coarse, denser unhealthy food environment and land use mix were statistically significant associated with childhood obesity outcomes (e.g 17.7 facilities/km² increase of unhealthy food environment (OR overweight/obesity status) = 1.20 [95% CI: 1.01; 1.44]). Cluster analysis identified 5 clusters of urban exposures. Compared to the most neutral cluster, the cluster with high air pollution, road traffic, and road noise levels was associated with a higher BMI and higher odds of overweight and obesity (β (zBMI) = 0.17, [95% CI: 0.01, 0.17]; OR (overweight/obesity) = 1.36, [95% CI: 0.99, 1.85]); the clusters were not associated with the weight-related behaviours.

CONCLUSIONS

This systematic study of many exposures in the urban environment suggests that an exposure pattern characterised by higher levels of ambient air pollution, road traffic and road traffic noise is associated with increased childhood obesity risk and that PM_coarse, land use mix and food environment are separately associated with obesity risk. These findings require follow-up in longitudinal studies and different settings.

Influence of Prevalence of Psychoactive Substance Use in Mexican Municipalities on Early Childhood Development

Children's early development is influenced by characteristics of the child, family, and environment, including exposure to substance abuse. The aim was to examine the association of early childhood development (ECD) with the prevalence of psychoactive substance use in Mexican municipalities. We obtained ECD data from the 2015 Survey of Boys, Girls, and Women (ENIM, for its Spanish acronym), measured with the ECD Index. The prevalence of psychoactive substance use was estimated at the municipal level, using the 2016 National Survey of Drug, Alcohol, and Tobacco Use (ENCODAT, for its Spanish acronym). Multilevel logistic models were fitted to evaluate the association between drug use and inadequacies in ECD overall and in four specific ECD domains: socio-emotional, literacy-numeric, learning, and physical. Inadequate ECD was directly associated with illegal drug use (OR = 1.10; 95% CI: 1.03, 1.17). For the specific ECD domains, inadequate socio-emotional development was directly associated with illegal drug use (OR = 1.08; 95% CI: 1.01, 1.15). These findings suggest that exposure to illegal drug use may influence ECD, and especially can lead to socio-emotional problems, although this cannot be considered the unanimous determinant of the problems presented. The implementation of evidence-based interventions to prevent drug abuse is necessary.

Access to bike lanes and childhood obesity: A systematic review and meta-analysis

The lack of bike lane access has been a proven risk factor for childhood obesity due to its role in discouraging healthy lifestyles. However, there has not been a systematic review of this important association in the existing literature. This study aims to fill this gap. A literature search was conducted in the Cochrane Library, PubMed, Embase, and Web of Science for studies published from 1 January 2019 onwards that examined the association between bike lane access and weight-related behaviours and outcomes among children aged <18 years. A total of 21 studies were included in this systematic review. Among them, most of the studies showed that bike lane access was significantly associated with children and adolescents' physical activity (PA), whereas only two studies showed a negative association. Meta-analysis also supported these findings and showed that bike lane access was significantly associated with children and adolescents' PA (odds ratio [OR] = 1.57, 95% confidence interval [CI]: 1.37-1.81). Additionally, we reviewed how bike lane characteristics and microenvironment variables such as children and adolescents' choice of bicycle travel mode, the degree of separation of cycle path, cycle path unevenness, and street maintenance were associated with adolescents' preferences and intention to cycle. This systematic review and meta-analysis strongly suggests that bike lane access is associated with children and adolescents' PA. Nonetheless, it was difficult to draw a conclusion on the association between bike lane access and weight-related outcomes.

Effects of Environment and Lifestyle Factors on Premature Ovarian Failure

Premature ovarian insufficiency (POI) or primary ovarian failure is defined as a cessation of the menstrual cycle in women younger than 40 years old. It is strictly defined as more than 4 months of oligomenorrhea or amenorrhea in a woman <40 years old, associated with at least two follicle-stimulating hormone (FSH) levels >25 U/L in the menopausal range, detected more than 4 weeks apart. It is estimated that POI was affected 1 and 2% of women. Although 80% of POI cases are of unknown etiology, it is suggested that genetic disorder, autoimmune origin, toxins, and environmental factors, as well as personal lifestyles, may be risk factors of developing POI. In this section, we will discuss the influences of environmental and lifestyle factors on POI. Moreover updated basic research findings regarding how these environmental factors affect female ovarian function via epigenetic regulations will also be discussed.

Urban environment during early-life and blood pressure in young children

BACKGROUND

The urban environment is characterised by many exposures that may influence hypertension development from early life onwards, but there is no systematic evaluation of their impact on child blood pressure (BP).

METHODS

Systolic and diastolic blood pressure were measured in 4,279 children aged 4-5 years from a multi-centre European cohort (France, Greece, Spain, and UK). Urban environment exposures were estimated during pregnancy and childhood, including air pollution, built environment, natural spaces, traffic, noise, meteorology, and socioeconomic deprivation index. Single- and multiple-exposure linear regression models and a cluster analysis were carried out.

RESULTS

In multiple exposure models, higher child BP, in particular diastolic BP, was observed in association with higher exposure to air pollution, noise and ambient temperature during pregnancy, and with higher exposure to air pollution and higher building density during childhood (e.g., mean change [95% confidence interval] for an interquartile range increase in prenatal NO₂ = 0.7 mmHg[0.3;1.2]). Lower BP was observed in association with higher temperature and better street connectivity during childhood (e.g., temperature = -1.1[-1.6;-0.6]). Some of these associations were not robust in the sensitivity analyses. Mother-child pairs were grouped into six urban environment exposure clusters. Compared to the cluster representing the least harmful urban environment, the two clusters representing the most harmful environment (high in air pollution, traffic, noise, and low in green space) were both associated with higher diastolic BP (1.3[0.1;2.6] and 1.5[0.5;2.5]).

CONCLUSION

This first large systematic study suggests that living in a harmful urban environment may impact BP regulation in children. These findings reinforce the importance of designing cities that promote healthy environments to reduce long-term risk of hypertension and other cardiovascular diseases.

Early life exposure to air pollution, green spaces and built environment, and body mass index growth trajectories during the first 5 years of life: A large longitudinal study

Urban environments are characterized by multiple exposures that may influence body mass index (BMI) growth in early life. Previous studies are few, with inconsistent results and no evaluation of simultaneous exposures. Thus, this study aimed to assess the associations between exposure to air pollution, green spaces and built environment characteristics, and BMI growth trajectories from 0 to 5 years. This longitudinal study used data from an electronic primary care health record database in Catalonia (Spain), including 79,992 children born between January 01, 2011 and December 31, 2012 in urban areas and followed until 5 years of age. Height and weight were measured frequently during childhood and BMI (kg/m²) was calculated. Urban exposures were estimated at census tract level and included: air pollution (nitrogen dioxide (NO₂), particulate matter <10 μm (PM₁₀) and <2.5 μm (PM_2.5)), green spaces (Normalized Difference Vegetation Index (NDVI) and % green space) and built environment (population density, street connectivity, land use mix, walkability index). Individual BMI trajectories were estimated using linear spline multilevel models with several knot points. In single exposure models, NO_2, PM_10, PM_2.5, and population density were associated with small increases in BMI growth (e.g. β per IQR PM₁₀ increase = 0.023 kg/m², 95%CI: 0.013, 0.033), and NDVI, % of green spaces and land use mix with small reductions in BMI growth (e.g. β per IQR % green spaces increase = -0.015 kg/m^2, 95%CI: -0.026, -0.005). These associations were strongest during the first two months of life. In multiple exposure models, most associations were attenuated, with only those for PM₁₀ and land use mix remaining statistically significant. This large longitudinal study suggests that early life exposure to air pollution, green space and built environment characteristics may be associated with small changes in BMI growth trajectories during the first years of life, and that it is important to account for multiple exposures in urban settings.

Natural environments in the urban context and gut microbiota in infants

The biodiversity hypothesis that contact with natural environments (e.g. native vegetation) and biodiversity, through the influence of environmental microbes, may be beneficial for human commensal microbiota has been insufficiently tested. We aimed to study the association between living near natural environments in the urban context, and gut microbiota diversity and composition in young infants. Based on data linkage between the unique Urban Primary Land and Vegetation Inventory (uPLVI) for the city of Edmonton and 355 infants in the CHILD Cohort Study, infant exposure to natural environments (any and specific types, yes/no) was determined within 500 m and 1000 m of their home residence. Gut microbiota composition and diversity at age 4 months was assessed in infant fecal samples. Adjusted for covariates, we observed a reduced odds of high microbial alpha-diversity in the gut of infants exposed to any natural environment within 500 m [Shannon index aOR (95%CI) = 0.63 (0.40, 0.98) and Simpson index = 0.63 (0.41, 0.98)]. In stratified analyses, these associations remained only among infants not breastfed or living with household pets. When doubly stratifying by these variables, the reduced likelihood of high alpha-diversity was present only among infants who were not breastfed and lived with household pets [9% of the study population, Shannon index = 0.07 (0.01, 0.49) and Simpson index = 0.11 (0.02, 0.66)]. Differences in beta-diversity was also seen (p = 0.04) with proximity to a nature space in not breastfed and pets-exposed infants. No associations were observed among infants who were fully formula-fed but without pets at home. When families and their pets had close access to a natural environment, Verrucomicrobiales colonization was reduced in the gut microbiota of formula-fed infants, the abundance of Clostridiales was depleted, whereas the abundance of Enterobacteriales was enriched. Our double-stratified results indicate that proximity to a natural environment plus pet ownership has the capacity to alter the gut microbiota of formula-fed infants. Further research is needed to replicate and better interpret these results, as well as to understand their health consequences.

Testing the Multiple Pathways of Residential Greenness to Pregnancy Outcomes Model in a Sample of Pregnant Women in the Metropolitan Area of Donostia-San Sebastián

Residential greenness may positively impact diverse human health indicators through the reduction of air pollution, the improvement of psychological health, and the promotion of physical activity. Previous studies indicate a weak but positive association with pregnancy outcomes. Our aim was to test the multiple pathways from residential greenness to pregnancy outcomes model, using residential NO₂ concentrations, psychological health, and moderate-to-vigorous physical activity (MVPA) during the first trimester of pregnancy, in a sample of 440 pregnant women residing in Donostia, Spain. Three metrics of residential greenness were calculated around each participant’s home address: normalized difference vegetation index (NDVI) within 300 m, and green space (>5000 m²) availability within 300 and 500 m. Residential NO₂ concentrations, psychological health, and MVPA were explored as mediators of the associations between these metrics and the following pregnancy outcomes: birth weight (BW), low birth weight (LBW), prematurity, small for gestational age (SGA), and large for gestational age (LGA). Educational attainment, parity, and body mass index (BMI) were treated as covariates. Counterfactual mediation analyses showed very low to null statistical support for an association between any of the greenspace metrics and pregnancy outcomes in the full sample. Green space availability (300 m) was associated with lower BW and showed a marginal protective effect against LGA.

Early-Life Environmental Exposures and Childhood Obesity: An Exposome-Wide Approach

BACKGROUND

Chemical and nonchemical environmental exposures are increasingly suspected to influence the development of obesity, especially during early life, but studies mostly consider single exposure groups.

OBJECTIVES

Our study aimed to systematically assess the association between a wide array of early-life environmental exposures and childhood obesity, using an exposome-wide approach.

METHODS

The HELIX (Human Early Life Exposome) study measured child body mass index (BMI), waist circumference, skinfold thickness, and body fat mass in 1,301 children from six European birth cohorts age 6-11 y. We estimated 77 prenatal exposures and 96 childhood exposures (cross-sectionally), including indoor and outdoor air pollutants, built environment, green spaces, tobacco smoking, and biomarkers of chemical pollutants (persistent organic pollutants, metals, phthalates, phenols, and pesticides). We used an exposure-wide association study (ExWAS) to screen all exposure-outcome associations independently and used the deletion-substitution-addition (DSA) variable selection algorithm to build a final multiexposure model.

RESULTS

The prevalence of overweight and obesity combined was 28.8%. Maternal smoking was the only prenatal exposure variable associated with higher child BMI (z-score increase of 0.28, 95% confidence interval: 0.09, 0.48, for active vs. no smoking). For childhood exposures, the multiexposure model identified particulate and nitrogen dioxide air pollution inside the home, urine cotinine levels indicative of secondhand smoke exposure, and residence in more densely populated areas and in areas with fewer facilities to be associated with increased child BMI. Child blood levels of copper and cesium were associated with higher BMI, and levels of organochlorine pollutants, cobalt, and molybdenum were associated with lower BMI. Similar results were found for the other adiposity outcomes.

DISCUSSION

This first comprehensive and systematic analysis of many suspected environmental obesogens strengthens evidence for an association of smoking, air pollution exposure, and characteristics of the built environment with childhood obesity risk. Cross-sectional biomarker results may suffer from reverse causality bias, whereby obesity status influenced the biomarker concentration. https://doi.org/10.1289/EHP5975.

Associations of the objective built environment along the route to school with children's modes of commuting: A multilevel modelling analysis (the SLIC study)

As active commuting levels continue to decline among primary schoolchildren, evidence about which built environmental characteristics influence walking or cycling to school remains inconclusive and is strongly context-dependent. This study aimed to identify the objective built environmental drivers of, and barriers to, active commuting to school for a multi-ethnic sample of 1,889 healthy primary schoolchildren (aged 5-11) in London, UK. Using cross-sectional multilevel ordered logistic regression modelling, supported by the spatial exploration of built environmental characteristics through cartography, the objective built environment was shown to be strongly implicated in children's commuting behaviour. In line with earlier research, proximity to school emerged as the prime variable associated with the choice for active commuting. However, other elements of the urban form were also significantly associated with children's use of active or passive modes of transport. High levels of accidents, crime and air pollution along the route to school were independently correlated with a lower likelihood of children walking or cycling to school. Higher average and minimum walkability and higher average densities of convenience stores along the way were independently linked to higher odds of active commuting. The significance of the relations for crime, air pollution and walkability disappeared in the fully-adjusted model including all built environmental variables. In contrast, relationships with proximity, traffic danger and the food environment were maintained in this comprehensive model. Black children, pupils with obesity, younger participants and those from high socioeconomic families were less likely to actively commute to school. There is thus a particular need to ensure that roads with high volumes of actively commuting children are kept safe and clean, and children's exposure to unhealthy food options along the way is limited. Moreover, as short commuting distances are strongly correlated with walking or cycling, providing high-quality education near residential areas might incite active transport to school.

Association of the built environment with physical activity in children and adolescents in Africa: a systematic review protocol

OBJECTIVE

The objective of this systematic review is to summarize the association between the built environment and physical activity in children and adolescents in Africa.

INTRODUCTION

Physical activity offers immense benefits to children and adolescents. Some built environment constructs, such as street connectivity and the availability of parks, have been identified to facilitate physical activity in children and adolescents; however, this evidence has come from developed countries. This review will present evidence from Africa on the built environment constructs that facilitate physical activity in children and adolescents.

INCLUSION CRITERIA

This review will consider quantitative studies that have built environment constructs as one of their exposure variables and physical activity as one of their outcomes and were conducted in children and adolescents aged five to 19 years residing in Africa.

METHODS

A systematic search of MEDLINE, Embase, Web of Science and other sources will be conducted to locate both published and unpublished studies. There will be no date or language restrictions. Titles, abstracts, and full text of articles retrieved from the search will be screened and read by two reviewers independently for eligibility. Included articles will be critically appraised independently by two reviewers. Data extraction will be performed in two phases, first for information regarding the study characteristics and then to extract specific study findings. Meta-analysis will be used to synthesize the findings from the studies; however, where this is not possible, a narrative synthesis will be performed.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42019133324.

Physical activity trails in an urban setting and cardiovascular disease morbidity and mortality in Winnipeg, Manitoba, Canada: a study protocol for a natural experiment

INTRODUCTION

Aspects of the built environment that support physical activity are associated with better population health outcomes. Few experimental data exist to support these observations. This protocol describes the study of the creation of urban trials on cardiovascular disease (CVD)-related morbidity and mortality in a large urban centre.

METHODS AND ANALYSIS

Between 2008 and 2010, the city of Winnipeg, Canada, built four, paved, multiuse (eg, cycling, walking and running), two-lane trails that are 5-8 km long and span ~60 neighbourhoods. Linking a population-based health data with census and environmental data, we will perform an interrupted time series analysis to assess the impact of this natural experiment on CVD-related morbidity and mortality among individuals 30-65 years of age residing within 400-1200 m of the trail. The primary outcome of interest is a composite measure of incident major adverse CVD events (ie, CVD-related mortality, ischaemic heart disease, stroke and congestive heart failure). The secondary outcome of interest is a composite measure of incident CVD-related risk factors (ie, diabetes, hypertension and dyslipidaemia). Outcomes will be assessed quarterly in the 10 years before the intervention and 5 years following the intervention, with a 4-year interruption. We will adjust analyses for differences in age, sex, ethnicity, immigration status, income, gentrification and other aspects of the built environment (ie, greenspace, fitness/recreation centres and walkability). We will also assess trail use and trail user profiles using field data collection methods.

ETHICS AND DISSEMINATION

Ethical approvals for the study have been granted by the Health Research Ethics Board at the University of Manitoba and the Health Information Privacy Committee within the Winnipeg Regional Health Authority. We have adopted an integrated knowledge translation approach. Information will be disseminated with public and government partners.

TRIAL REGISTRATION NUMBER

NCT04057417.

Neighborhood characteristics associated with park use and park-based physical activity among children in low-income diverse neighborhoods in New York City

Urban parks provide spaces and facilities for children's physical activity (PA) and can be a free resource in low-income communities. This study examined whether neighborhood characteristics were associated with children's park use and park-based moderate-to-vigorous PA (MVPA) in low-income diverse communities and how associations differed between ethnic groups. Data on park visits and MVPA came from 16,402 children 5-10-years old directly observed using the System for Observing Play and Recreation in Communities in 20 parks in low-income neighborhoods with majority Latino or Asian populations in New York City. Neighborhood characteristics included land use mix (LUM), street audits, crime rates, and an area deprivation index. We employed Poisson and negative binomial models to estimate effects of neighborhood-level variables on the number of children observed in parks and engaging in MVPA, overall and by ethnicity. Results for Asian, Latino, and African American children indicated that higher levels of LUM and pedestrian-friendly streets were associated with greater numbers of children in parks and higher MVPA across all three groups. For Asian and Latino children only, quality of environment was positively associated with MVPA, whereas level of deprivation and crime rates in the surrounding neighborhood were negatively associated with children's park-based MVPA. In contrast, a park's access to public transportation was negatively associated with number of all children observed and engaging in MVPA. Study findings suggest that park-based MVPA interventions can be informed by understanding how neighborhood characteristics facilitate and constrain park use and park-based MVPA.