Childhood social position and associations between environmental exposures and health outcomes

Association Between Socioeconomic Status and Prevalence of Hypersensitivity Diseases and Autism: A Nationwide Study of Children

OBJECTIVE

Prior research suggests that children with a low socioeconomic status (SES) background are at an increased risk for special healthcare needs. Conversely, for hypersensitivity-related diseases, many studies reported a lower risk among children with lower SES according to the hygiene hypothesis. We aimed to evaluate the association between SES and several hypersensitivity diseases and autism in a representative American sample.

METHODS

We used data from the 2016, 2017 and 2018 US National Survey of Children's Health. A total of 102,341 children aged 0-17 years were included. The dependent variables were doctor-diagnosed allergies, arthritis, asthma, diabetes, and autism. The main SES indicators were family poverty levels, highest education of the reported adults and difficulty in family income. Our analysis used logistic regression that accounted for the survey sampling design.

RESULTS

The sample had a mean age of 9.4 ± 5.3 years. The weighted prevalence for allergies was 24.4%, 0.3% for arthritis, 11.9% for asthma, 0.5% for diabetes and 2.6% for autism. Children with adults reporting higher educational levels had greater odds of allergies (adjusted odds ratio and 95% CI: 1.48, 1.23-1.78) than those with lower educational levels. But for all other diseases, most findings suggested that a higher odds of disease was associated with lower SES instead of higher SES.

CONCLUSIONS

A low SES background remains an important risk factor for hypersensitivity diseases in children. Most of our results suggested that children with low SES were associated with a higher risk of hypersensitivity diseases and autism.

Socioeconomic disadvantage and health in early childhood: a population-based birth cohort study from Portugal

BACKGROUND

Measuring early socioeconomic inequalities in health provides evidence to understand the patterns of disease. Thus, our aim was to determine which children's health outcomes are patterned by socioeconomics and to what extent the magnitude/direction of the differences vary by socioeconomic measure and outcome.

METHODS

Data on early childhood (4 years) health was obtained from Generation XXI birth cohort (n = 8647). A total of 27 health outcomes and 13 socioeconomic indicators at the individual level and neighbourhood level were used to calculate the relative index of inequality (RII).

RESULTS

Socioeconomic inequalities were evident across 21 of the 27 health outcomes. Education, occupation and income more often captured inequalities, compared with neighbourhood deprivation or employment status. Using highest maternal education as reference category, we observed that seizures (RII = 8.64), obesity (2.94), abdominal obesity (2.66), urinary tract infection (2.26), language/speech problems (2.24), hypertension (2.08) and insulin resistance (1.33) were heavily socially patterned, much more common in disadvantaged children. Contrastingly, eczema (0.26) and rhinitis (0.26) were more common among more advantaged children.

CONCLUSIONS

Socioeconomic inequalities were evident for almost every health outcome assessed, although with varying magnitude/direction according to the socioeconomic indicator and outcome. Our results reinforce that the social gradient in health manifests early in childhood.

Children and youth's biopsychosocial wellbeing in the context of energy resource activities

BACKGROUND

Children and youth emerge as key populations that are impacted by energy resource activities, in part because of their developmental vulnerabilities, as well as the compounding effects of energy systems on their families, communities, and physical environments. While there is a larger literature focused on fossil fuel emissions and children, the impacts of many aspects of energy systems on children and youth remain under examined and scattered throughout the health, social science, and environmental science literatures.

OBJECTIVES

This systematic interdisciplinary review examines the biological, psychosocial, and economic impacts of energy systems identified through social science research - specifically focused on household and industrial extraction and emissions - on children and youth functioning.

METHODS

A critical interpretive search of interdisciplinary and international social sciences literature was conducted using an adaptive protocol focusing on the biopsychosocial and economic impacts of energy systems on children and youth. The initial results were complemented with a purposeful search to extend the breadth and depth of the final collection of articles.

DISCUSSION

Although relatively few studies have specifically focused on children and youth in this context, the majority of this research uncovers a range of negative health impacts that are directly and indirectly related to the development and ongoing operations of natural resource production, particularly oil and gas, coal, and nuclear energy. Psychosocial and cultural effects, however, remain largely unexamined and provide a rich avenue for further research.

CONCLUSIONS

This synthesis identifies an array of adverse biopsychosocial health outcomes on children and youth of energy resource extraction and emissions, and identifies gaps that will drive future research in this area.

An Overview of Literature Topics Related to Current Concepts, Methods, Tools, and Applications for Cumulative Risk Assessment (2007-2016)

Cumulative risk assessments (CRAs) address combined risks from exposures to multiple chemical and nonchemical stressors and may focus on vulnerable communities or populations. Significant contributions have been made to the development of concepts, methods, and applications for CRA over the past decade. Work in both human health and ecological cumulative risk has advanced in two different contexts. The first context is the effects of chemical mixtures that share common modes of action, or that cause common adverse outcomes. In this context two primary models are used for predicting mixture effects, dose addition or response addition. The second context is evaluating the combined effects of chemical and nonchemical (e.g., radiation, biological, nutritional, economic, psychological, habitat alteration, land-use change, global climate change, and natural disasters) stressors. CRA can be adapted to address risk in many contexts, and this adaptability is reflected in the range in disciplinary perspectives in the published literature. This article presents the results of a literature search and discusses a range of selected work with the intention to give a broad overview of relevant topics and provide a starting point for researchers interested in CRA applications.

Prevalence of non-food allergies among non-immigrants, long-time immigrants and recent immigrants in Canada

OBJECTIVES

The prevalence of allergic conditions has been increasing worldwide, with the highest rates seen in Western countries like Canada. The development of allergies is known to be related to both genetic and environmental factors, but the causal pathways remain unclear. Studies on immigrants provide a unique opportunity to disentangle these two factors and provide a better understanding of the disease aetiology. The aim of this study was to investigate the relationship between immigration status and prevalence of non-food allergies in a population-based study of Canadians.

METHODS

Data of 116,232 respondents from the Canadian Community Health Survey (Cycle 3.1, 2005) were used in a multivariable logistic regression to assess the association between immigration status (non-immigrant, long-time immigrant [>10 years] and recent immigrant [≤10 years]) and self-reported doctor-diagnosed non-food allergies, adjusting for potential confounders.

RESULTS

The highest prevalence of non-food allergies was found among non-immigrants (29.6%), followed by long-time immigrants (23.9%) and then recent immigrants (14.3%). The odds of non-food allergies were reduced by 60% (OR = 0.40, 95% CI: 0.35, 0.45) among recent immigrants and 25% (OR = 0.75, 95% CI: 0.70, 0.80) among long-time immigrants, compared with non-immigrants, after adjusting for sex, age, socio-economic status and rurality.

CONCLUSION

This study finds a distinctly lower prevalence of non-food allergies among immigrants compared with non-immigrants, with the difference diminishing with longer duration of residence in Canada. The findings highlight the potential of environmental determinants of allergy development that warrant further investigation, and demonstrate the need for multicultural strategies to manage the public health burden of allergic conditions.

A systematic review of socioeconomic position in relation to asthma and allergic diseases

The role of socioeconomic position (SEP) in the development of asthma and allergies is unclear, with some pointing to the risks of low SEP and other research pointing in the direction of higher SEP being associated with higher prevalence rates. The aim of this systematic review is to clarify associations between SEP and the prevalence of asthma and allergies. Out of 4407 records identified, 183 were included in the analysis. Low SEP was associated with a higher prevalence of asthma in 63% of the studies. Research on allergies, however, showed a positive association between higher SEP and illness in 66% of studies. Pooled estimates for the odds ratio of disease for the highest compared with the lowest SEP confirmed these results for asthma (unadjusted OR 1.38, 95% CI 1.37-1.39), allergies in general (OR 0.67, 95% CI 0.62-0.72), atopic dermatitis (unadjusted OR 0.72, 95% CI 0.61-0.83) and allergic rhinoconjunctivitis (unadjusted OR 0.52, 95% CI 0.46-0.59). Sensitivity analyses with a subsample of high-quality studies led to the same conclusion. Evidence from this systematic review suggests that asthma is associated with lower SEP, whereas the prevalence of allergies is associated with higher SEP.

A systematic review on the development of asthma and allergic diseases in relation to international immigration: the leading role of the environment confirmed

BACKGROUND

The prevalence of asthma and allergic diseases is rising worldwide. Evidence on potential causal pathways of asthma and allergies is growing, but findings have been contradictory, particularly on the interplay between allergic diseases and understudied social determinants of health like migration status. This review aimed at providing evidence for the association between migration status and asthma and allergies, and to explore the mechanisms between migration status and the development of asthma and allergies.

METHODS AND FINDINGS

Systematic review on asthma and allergies and immigration status in accordance with the guidelines set by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The pooled odds ratio (OR) of the prevalence of asthma in immigrants compared to the host population was 0.60 (95% CI 0.45-0.84), and the pooled OR for allergies was 1.01 (95% CI 0.62-1.69). The pooled OR for the prevalence of asthma in first generation versus second generation immigrants was 0.37 (95% CI 0.25-0.58). Comparisons between populations in their countries of origin and those that emigrated vary depending on their level of development; more developed countries show higher rates of asthma and allergies.

CONCLUSIONS

Our findings suggest a strong influence of the environment on the development of asthma and allergic diseases throughout the life course. The prevalence of asthma is generally higher in second generation than first generation immigrants. With length of residence in the host country the prevalence of asthma and allergic diseases increases steadily. These findings are consistent across study populations, host countries, and children as well as adults. Differences have been found to be significant when tested in a linear model, as well as when comparing between early and later age of migration, and between shorter and longer time of residence.

Asthma, respiratory symptoms and lung function in children living near a petrochemical site

Residential proximity to environmental hazards has been related to adverse health outcomes. Respiratory health and allergies in children living near petrochemical sites have not been extensively studied. We evaluated the association between residential proximity to the petrochemical site of Tarragona (Catalonia, Spain) and the prevalence of asthma, respiratory symptoms and lung function in children. Children aged 6-7 (n=2672) and adolescents aged 13-14 (n=2524) residing near two large petrochemical sites and those living in a city with medium vehicular traffic were cross-sectionally compared with children from an area with low vehicular traffic and without industry. The prevalence of symptoms was measured using the International Study of Asthma and Allergies in Childhood written and video questionnaires. Lung function measurements were done in a subsample of 959 adolescents in the four areas. Multivariable analyses were done to estimate the effects of the residential area on symptoms and lung function adjusted for potential confounders. Crude prevalence of symptoms was similar across the studied areas. After adjustment, children and adolescents living near a petrochemical site had a statistically significant higher prevalence of respiratory hospitalizations in the previous year (Prevalence Ratio (PR)=1.49; 95%CI, 1.06-2.09) and of nocturnal cough (PR=1.29; 95%CI 1.05-1.57), respectively. Reduced lung function values among adolescents residing near the petrochemical areas were not observed. Although a higher prevalence of asthma in children and adolescents living near the petrochemical sites could not be demonstrated, as described in other studies, respiratory hospitalizations and nocturnal cough could be related to short-term exposures to pollutants. Other clinical and sub-clinical respiratory health effects in the petrochemical industry areas should be investigated.

Les résidences pour personnes âgées de l’île de Montréal appartenant aux parcs social et privé : une exposition inéquitable à la pollution de l’air ?

La qualité des milieux à proximité des résidences pour personnes âgées sur l’île de Montréal, tant celles du parc privé que du parc social, est analysée sous l’angle de la pollution générée par la circulation automobile. Deux types d’indicateurs de polluants sont utilisés pour évaluer la pollution. Les premiers sont basés sur la proximité des axes majeurs de circulation et les seconds estiment, dans un rayon de 200 m, la concentration de NO2. Nos résultats montrent que les résidences privées et celles du parc social se localisent plus souvent à proximité d’axes majeurs de circulation que les résidences de l’ensemble de la population et de la population âgée. Les résidences privées se caractérisent toutefois par des concentrations moindres de NO2 comparativement à ces deux mêmes populations, alors qu’on observe l’inverse pour les résidences du parc social. Ceci s’explique notamment par leur distribution respective au sein du territoire urbanisé.

Relative effects of educational level and occupational social class on body concentrations of persistent organic pollutants in a representative sample of the general population of Catalonia, Spain

Scant evidence is available worldwide on the relative influence of occupational social class and educational level on body concentrations of persistent organic pollutants (POPs) in the general population. The objective was to analyse such influence in a representative sample of the general population of Catalonia, Spain. Participants in the Catalan Health Interview Survey aged 18-74 were interviewed face-to-face, gave blood, and underwent a physical exam. The role of age, body mass index (BMI), and parity was analysed with General Linear Models, and adjusted geometric means (GMs) were obtained. Crude (unadjusted) concentrations were higher in women and men with lower education, and in women, but not men, in the less affluent social class. After adjusting for age, in women there were no associations between POP levels and social class or education. After adjusting for age and BMI, men in the less affluent class had higher p,p'-DDE concentrations than men in class I (p-value=0.016), while men in class IV had lower HCB than men in the upper class (p-value<0.03). Also in contrast with some expectations, positive associations between education and POP levels were observed after adjusting for age and BMI in men; e.g., men with university studies had higher HCB concentrations than men with first stage of primary schooling (adjusted GM 153.9 and 80.5ng/g, respectively) (p-value<0.001). When education and social class were co-adjusted for, some positive associations with education in men remained statistically significant, whereas class remained associated only with p,p'-DDE. Educational level influenced blood concentrations of POPs more than occupational social class, especially in men. In women, POP concentrations were mainly explained by age/birth cohort, parity and BMI. In men, while concentrations were also mainly explained by age/birth cohort and BMI, both social class and education showed positive associations. Important characteristics of socioeconomic groups as age and BMI may largely explain crude differences among such groups in internal contamination by POPs. The absence of clear patterns of relationships between blood concentrations of POPs and indicators of socioeconomic position may fundamentally be due to the widespread, lifelong, and generally invisible contamination of human food webs. Decreasing historical trends would also partly explain crude socioeconomic differences apparently due to birth cohort effects.

Reaching families at their homes for an intervention to reduce tobacco smoke exposure among infants

The methods of reaching families for a home intervention trial (HIT) were analyzed in this study. The study aimed to reduce environmental tobacco smoke exposure among infants in one region of Germany. The systematic screening data of smoking among families in their homes were compared with reference data of a representative household sample of the state in which the study was conducted. The characteristics of participating and non-participating families were analyzed. All households (N = 3,570) containing at least one infant age 3 years or younger were selected using the residents` registration files and invited to participate in a screening assessment. Among these families, 3,293 (92.2 %) were contacted and from that group, 2,641 families participated in the screening. Compared with the reference sample, the screened sample included a higher proportion of families with employment and with more than 10 years of education. Participation in the HIT was recommended if at least one parent reported smoking one or more cigarettes per day during the previous 4 weeks. Among the 1,282 families that met the inclusion criteria, 71.5 % took part in the screening. Participating families, compared with non-participating families, were older, included more families with two parents living in the household, and had higher rates of employment. The effect size of the final regression model was small (Cohen's f (2) = 0.01). In conclusion, proactive approaches that are delivered at home may yield a high reach of the target population and particularly of socioeconomically disadvantaged populations.

Ecological study on hospitalizations for cancer, cardiovascular, and respiratory diseases in the industrial area of Etang-de-Berre in the South of France

The Etang-de-Berre area is a large industrialized area in the South of France, exposing 300,000 inhabitants to the plumes of its industries. The possible associated health risks are of the highest concern to the population, who asked for studies investigating their health status. A geographical ecological study based on standardized hospitalizations ratios for cancer, cardiovascular, and respiratory diseases was carried out over the 2004–2007 period. Exposure to air pollution was assessed using dispersion models coupled with a geographic information system to estimate an annual mean concentration of sulfur dioxide (SO₂) for each district. Results showed an excess risk of hospitalization for myocardial infarction in women living in districts with medium or high SO₂ exposure, respectively, 38% [CI 95% 4 : 83] and 54% [14 : 110] greater than women living in districts at the reference level exposure. A 26% [2 : 57] excess risk of hospitalization for myocardial infarction was also observed in men living in districts with high SO₂ levels. No excess risk of hospitalization for respiratory diseases or for cancer was observed, except for acute leukemia in men only. Results illustrate the impact of industrial air pollution on the cardiovascular system and call for an improvement of the air quality in the area.

[The correlation between smoking, environmental tobacco smoke and preterm birth]

The rate of preterm births is very high in Hungary; it was 8.9% of the total livebirths in 2010. Preterm birth (<37 weeks) has a considerable health impact, because it is responsible for 85% of infant mortality and morbidity as well as for numerous chronic diseses in the long-term. Many maternal and fetal diseases can be identified in the background, but in a number of cases, preterm labor begins unexpectedly, without any prodrome. Presumably, the socioeconomic background and the presence of harmful lifestyle factors are related to preterm birth in these cases. Tobacco smoking is the most frequent harmful health behavior. At national level, the rate of smoking during pregnancy was 14.4% in the last 13 years, but in some counties, this proportion mounted to 25%. In these counties, the prevalence of preterm births also exceeds the national average. This summary highlights the factors related to disadvantaged socio-economic status that can be responsible for the higher number of preterm birth cases.

Assessment of environmental and socio-economic stress

Since long, socio-economic status, often expressed as an index, is known to correlate with health outcomes like behavioural problems. We constructed a new index that encapsulated not only economic and social but also environmental stressors (ESES), using data of the German Health Interview and Examination Survey for Children and Adolescents, a nation-wide representative surveillance of 17,641 participants aged between 0-17 years. Different factors were selected to account for socio-economic stress (low parental education, low household income, low occupational status of the householder), domestic stress (living in large cities, exposure to tobacco smoke at home, crowded housing, mouldy walls), and prenatal stress (maternal smoking during pregnancy, drinking alcohol during pregnancy). Prior to the calculation of ESES, the different factors were multiplied by weights which were estimated by multivariate linear regression on a number of health outcomes. ESES was then used to predict emotional and social problems (SDQ scores). The resulting ORs were compared with those obtained for an established socio-economic index (SEI). ESES was superior to SEI as it could more clearly identify children and adolescents with emotional or social problems. Different types of stressors (i.e. socio-economic stress, domestic stress and prenatal stress) contributed independently to emotional and social problems.