Association between environmental factors and current asthma, rhinoconjunctivitis and eczema symptoms in school-aged children from Oropeza Province--Bolivia: a cross-sectional study

Healthcare Disparities in Atopic Dermatitis in Latin America: A Narrative Review

INTRODUCTION

Atopic dermatitis (AD) is a chronic, pruritic skin disease caused by a mixture of genetic, immunological, and environmental factors, characterized by periods of inflammation and remission. In Latin America (LA), the prevalence of AD ranges up to 25% in children and 1-3% in adults. The natural history of the disease for most patients is that AD goes into remission in adolescence and adult life. Only 10-30% of patients continue to have symptoms of the disease in adulthood. There are patients (3-4%) who have the onset of AD during adolescence or after adulthood. Those with limited access to healthcare services, such as diagnosis and treatment, have increased difficulties coping with AD. Healthcare disparities are a complex topic that include social, political, racial/ethnic, and geographical factors. Publications about healthcare disparities in AD in LA are scarce. As a result, recognizing and resolving healthcare inequalities is critical to improving the treatment and quality of life (QoL) of individuals with AD.

METHODS

A panel of Latin American experts in dermatology and allergies was provided with a series of relevant questions to address before a multiday conference. During this conference, the entire group discussed and edited each narrative through numerous drafts and rounds of discussion until they reached a consensus.

RESULTS

This paper examines the barriers to equal access to care and recommends realistic actions to overcome them. Inadequate disease knowledge, cultural and linguistic barriers, stigmatization, maldistribution of resources, absence of local clinical practice guidelines, arduous patient journey, and limited consultation time were identified as causes of health inequality.

CONCLUSIONS

Among the suggested solutions are enhanced education for healthcare professionals, patients, and the general public, a focus on underprivileged communities, telemedicine and telementoring, translators, multidisciplinary teams, and local living clinical practice guidelines.

Air Pollution and Atopic Dermatitis, from Molecular Mechanisms to Population-Level Evidence: A Review

Atopic dermatitis (AD) has increased in prevalence to become the most common inflammatory skin condition globally, and geographic variation and migration studies suggest an important role for environmental triggers. Air pollution, especially due to industrialization and wildfires, may contribute to the development and exacerbation of AD. We provide a comprehensive, multidisciplinary review of existing molecular and epidemiologic studies on the associations of air pollutants and AD symptoms, prevalence, incidence, severity, and clinic visits. Cell and animal studies demonstrated that air pollutants contribute to AD symptoms and disease by activating the aryl hydrocarbon receptor pathway, promoting oxidative stress, initiating a proinflammatory response, and disrupting the skin barrier function. Epidemiologic studies overall report that air pollution is associated with AD among both children and adults, though the results are not consistent among cross-sectional studies. Studies on healthcare use for AD found positive correlations between medical visits for AD and air pollutants. As the air quality worsens in many areas globally, it is important to recognize how this can increase the risk for AD, to be aware of the increased demand for AD-related medical care, and to understand how to counsel patients regarding their skin health. Further research is needed to develop treatments that prevent or mitigate air pollution-related AD symptoms.

Study Protocol to Determine Association between Environmental Triggers and Asthma among Children in King Williams Town

Asthma affects over 330 million people worldwide, with relatively higher disease burdens in Australia, New Zealand, Africa, the Middle East, and South America. The symptoms associated with asthma were reported to be prevalent in children from the period of 1993 to 2013, in many low- and middle-income countries, due to changes in environmental conditions, such as domestic lifestyle, and urban and industrial developments. (1) Background: Several studies have also shown that children are prone to a severe type of asthma, because of their narrow respiratory airways and susceptibility to irritation from environmental agents. This study aimed to assess the association between environmental exposure and asthma among children in King Williams Town, South Africa. (2) Methodology: This study adopted a cross-sectional design method, with an estimated sample size of 262 participants. The eligible study participants were enrolled while attending Grey hospital in King Williams Town, for asthma management. Information will be collected from eligible, stable participants, on asthma treatment, through in-person interviewing in 2021. A semi-structured questionnaire will be administered to the participants. However, as a result of the prevailing COVID-19 pandemic, data may be abstracted from the asthma medical record of the eligible participants. Multivariate regression will be utilized, to describe the correlation between the variables, and the odds ratio will be calculated as well. (3) Discussion and conclusion: The study will objectively identify the local environmental agents that are associated with asthma among children in King Williams Town, in order to reprioritize treatment and preventative strategies. Ethical approval was obtained from the Research Ethics Committee, Faculty of Health Sciences at the University of Johannesburg.

The Unmet Needs in Atopic Dermatitis Control in Latin America: A Multidisciplinary Expert Perspective

Introduction

Adoption of control tools for atopic dermatitis (AD) in Latin America (LA) is currently very limited. Clinical assessment tools represent a practical method to measure the impact of treatment on disease activity and on the quality of life of patients. However, the use of these tools in the LA clinical practice setting is limited.

Methods

A selected panel of Latin American experts in fields related to atopic dermatitis were provided with a series of relevant questions to address prior to the multi-day conference. Within this conference, each narrative was discussed and edited by the entire group, through numerous drafts and rounds of discussion, until a consensus was achieved.

Results

The panel proposes specific and realistic recommendations for implementing control tools for AD care in LA. In creating these recommendations, the authors strove to address all barriers to the widespread use of these tools.

Conclusion

This article includes a narrative analysis of barriers to AD control in LA and provides necessary recommendations to integrate and increase the use of validated AD control assessment tools throughout the region.

Allergic rhinitis aggravated by air pollutants in Latin America: A systematic review

The aim of this systematic review (SR) was to evaluate the most frequent pollutants and their effect on allergic rhinitis in Latin American countries. Observational studies up to December 2020 and comparing different indoor and outdoor pollutants that had allergic rhinitis (AR) as an outcome were included in the systematic review. Random-effect meta-analyses were conducted for the presence of allergic rhinitis. Estimates were presented as pooled odds ratios (ORs) and their respective 95% confidence intervals (CIs). Twenty-two publications comprised this review according to the inclusion and exclusion criteria and 12 had data that could be analyzed statistically. The most frequent pollutant was PM10, followed by NO2 /O3 and PM2.5 in studies conducted in Argentina, Brazil, Bolivia, Chile, Colombia, Costa Rica, and Peru. The OR of an exposed subject experiencing allergic rhinitis was 1.43 (95% CI 1.026; 1.980). The OR of children and adolescents experiencing of allergic rhinitis was 1.359 (95% CI 1.051; 1.759). Asymmetry and great variability in the effect estimated from the selected studies were observed. The publication bias was quantified by Kendall's correlation and Egger's test resulted in 0.152 (p-value = 0.493). Egger's test provided an intercept equal to 2.511 and a p-value = 0.398. The I2 statistic was 89.3% and reinforces the hypothesis of heterogeneity. This first systematic review conducted in Latin America confirmed the chance of a person exposed to pollutants and experiencing allergic rhinitis is 43% greater than that of a non-exposed person, reinforcing the importance of policies to reduce pollutant exposure and the use of protection systems for workforces exposed to occupational pollutants in work environments.

Application of data science methods to identify school and home risk factors for asthma and allergy-related symptoms among children in New York

OBJECTIVES

Few studies have comprehensively assessed multiple environmental exposures affecting children's health. This study applied machine-learning methods to evaluate how indoor environmental conditions at home and school contribute to asthma and allergy-related symptoms.

METHODS

We randomly selected 10 public schools representing different socioeconomic statuses in New York State (2017-2019) and distributed questionnaires to students to collect health status and home-and school-environmental exposures. Indoor air quality was measured at school, and ambient particle exposures (PM_2.5 and components) were measured using real-time personal monitors for 48 h. We used random forest model to identify the most important risk factors for asthma and allergy-related symptoms, and decision tree for visualizing the inter-relationships among the multiple risk factors with the health outcomes.

RESULTS

The top contributing factors identified for asthma were family rhinitis history (relative importance: 10.40%), plant pollen trigger (5.48%); bedroom carpet (3.58%); environmental tobacco smoke (ETS) trigger symptom (2.98%); and ETS exposure (2.56%). For allergy-related symptoms, plant pollen trigger (10.88%), higher paternal education (7.33%), bedroom carpet (5.28%), family rhinitis history (4.78%), and higher maternal education (4.25%) were the strongest contributing factors. Conversely, primary heating with hot water radiator was negatively (-6.86%) associated with asthma symptoms. Younger children (<9 years old) with family history of rhinitis and carpeting in the bedroom were the prominent combined risk factors for asthma. Children jointly exposed to pollen, solvents, and carpeting in their home tended to have greater risks of allergy-related symptoms, even without family history of rhinitis.

CONCLUSION

Family rhinitis history, bedroom carpet, and pollen triggers were the most important risk factors for both asthma and allergy-related symptoms. Our new findings included that hot-water radiator was related to reduced asthma symptoms, and the combination of young age, rhinitis history, and bedroom carpeting was related to increased asthma symptoms. Further studies are needed to confirm our findings.

Assessment of personal exposure to particulate air pollution in different microenvironments and traveling by several modes of transportation in Bogotá, Colombia: protocol for a mixed-methods study. (Preprint)

Background

Air pollution in most countries exceeds the levels recommended by the World Health Organization, causing up to one-third of deaths due to noncommunicable diseases. Fine particulate matter (PM_2.5) and black carbon (BC) from mobile sources are the main contaminants.

Objective

The aim of this study is to assess the relationship of exposure to air pollutants (PM_2.5 and BC) in microenvironments according to respiratory health and physical activity in users traveling by different types of transportation in Bogotá, Colombia.

Methods

A mixed methods study based on a convergent parallel design will be performed with workers and students. The sample will include 350 healthy transport users traveling by different urban transportation modes in three main routes in Bogotá. The study is broken down into two components: (1) a descriptive qualitative component focused on assessing the individual perception of air pollution using semistructured interviews; and (2) a cross-sectional study measuring the individual exposure to PM_2.5 and BC using portable instruments (DustTrak and microAeth, respectively), pulmonary function by spirometry, and physical activity with accelerometry. The analysis will include concurrent triangulation and logistic regression.

Results

The findings will be useful for the conception, design, and decision-making process in the sectors of health and mobility from public, academy, and private perspectives. This study includes personal measurements of PM_2.5 and BC during typical trips in the city to assess the exposure to these contaminants in the major roadways in real time. The study further compares the performance of two different lung tests to identify possible short-term respiratory effects. As a limitation, the protocol will include participants from different institutions in the city, which are not necessarily representative of all healthy populations in Bogotá. In this sense, it is not possible to draw causation conclusions. Moreover, a convergent parallel design could be especially problematic concerning integration because such a design often lacks a clear plan for making a connection between the two sets of results, which may not be well connected. Nevertheless, this study adopts a procedure for how to integrate qualitative and quantitative data in the interpretation of the results and a multilevel regression. The time that participants must live in the city will be considered; this will be controlled in the stratified analysis. Another limitation is the wide age range and working status of the participants. Regional pollution levels and episodes (PM_2.5) will be handled as confounding variables. The study is currently in the enrollment phase of the participants. Measurements have been made on 300 participants. Pandemic conditions affected the study schedule; however, the results are likely to be obtained by late 2022.

Conclusions

This study investigates the exposure to air pollutants in microenvironments in Bogotá, Colombia. To our knowledge, this is the first mixed methods study focusing on PM_2.5, BC, and respiratory health effects in a city over 2 meters above sea level. This study will provide an integration of air pollution exposure variables and respiratory health effects in different microenvironments.

International Registered Report Identifier (IRRID)

PRR1-10.2196/25690

Overcrowding and health in two impoverished suburbs of Johannesburg, South Africa

Background

Rapid urbanization, unmatched by an associated supply of housing, has resulted in overcrowding in the cities of many developing countries, including in Johannesburg, South Africa. Household overcrowding has been associated with a range of ill-health outcomes, including acute respiratory infections and diarrhoeal diseases. The aim of this study was to describe the levels of household crowding, and examine associations with respiratory and gastrointestinal symptoms in selected two low-income neighbourhoods in Johannesburg.

Methods

Questionnaire data from a panel study conducted over an 11-year period between 2006 and 2016 were extracted to conduct the analyses. Structured questionnaires, designed to collect information on housing conditions, socio-economic and health status were administered to adult representatives of households occupying the primary dwelling on pre-selected study sites.

Results

Over the 11-year study period, levels of overcrowding remained unchanged. Around 57.6% of dwellings in the study neighbourhoods were determined to be overcrowded in relation to international guidelines. Results from the multiple logistic regression analyses indicated that crowded dwellings were associated with elevated levels of acute respiratory and gastrointestinal symptoms, as well as fever/chills.

Conclusion

Respondent perceptions varied from objective measures of overcrowding. Crowded dwellings were associated with elevated reports of acute respiratory and gastrointestinal symptoms, as well as fever/chills.

[Air pollution and atopic eczema : Systematic review of findings from environmental epidemiological studies]

BACKGROUND

Among the many risk factors for the development of atopic eczema (AE), the influence of air pollution has recently been discussed more often. A systematic review about this topic however is lacking.

AIMS

Which effects of outdoor air pollution (particles, nitric oxides, sulfur dioxide, ozone or general traffic exhaust emissions) on AE can be demonstrated in a systematic analysis of available environmental epidemiologic studies?

METHODS

All environmental epidemiologic studies on AE and air pollution found in the literature database PubMed were identified. The most important key figures of these studies were tabulated, the quality of evidence was graded and the studies described.

RESULTS

A total of 57 studies were identified. Only one of the 15 cross-sectional studies with a large-scale exposure assessment found a significant association between AE and air pollution. In contrast 23 of 30 studies with small-scale exposure assessment found a significant association between AE and traffic related emissions-especially from trucks. Of the 30 studies, 14 were cohort studies (1 adult, 13 birth cohorts). The sole adult cohort found an association with intrinsic AE. In the East Asian cohorts (all published since 2015), an association between maternal exposure to traffic-related pollution and incidence of AE in the offspring was found. This was less clear in cohorts from Europe/US or simply not investigated. In 5/5 panel studies (all from South Korea), symptom severity of AE was found to be significantly and positively related to outdoor air pollution.

CONCLUSIONS

In a systematic analysis of environmental epidemiologic studies about air pollution and AE rather good evidence was found that, based on small-scale exposure measurements, especially truck traffic emissions increased AE prevalence, while large-scale exposure to larger particles (PM10) or SO₂ was without effect. Considering pathophysiologic aspects traffic exhaust emissions seem to affect both skin barrier function and activation of immune responses.

Exposure to dogs but not cats is associated to a decrease in the prevalence in atopic dermatitis amongst school-children

INTRODUCTION

The association regarding the exposure to pets, especially cats and dogs, and the prevalence of allergic diseases is inconsistent.

OBJECTIVE

We analyzed the role played by early exposure to dogs or cats in the prevalence of allergic diseases amongst school-aged children.

METHOD

Through a cross-sectional study, we examined 756 children, aged 6-7; these candidates were selected through cluster sampling. We inquired about the exposure that these children had had to dogs and cats, and whether these pets spent most of their time indoors or outdoors during the first year of the child's life. In order to identify the prevalence of allergic diseases and their symptoms, each child's parent completed the International Study of Asthma and Allergies in Childhood questionnaire.

RESULTS

Exposure to outdoor dogs was associated to nocturnal coughing, odds ratio (OR) 0.64, with a confidence interval of 95% (95% CI) 0.43-0.95 and with atopic dermatitis (OR: 0.39; 95% CI: 0.20-0.76). Interestingly, exposure to outdoor cats was associated to nocturnal coughing (OR: 0.51; 95% CI: 0.32-0.83) and current rhinitis symptoms (OR: 0.59; 95% CI 0.36-0.97). After carrying out the multivariate analyses, only exposure to dogs, both indoor and outdoor, was significantly associated to a decrease in the prevalence of atopic dermatitis OR 0.40 (95% CI: 0.20-0.79) and OR 0.38 (95% CI: 0.18-0.83), respectively.

CONCLUSION

Our findings suggest that exposure to dogs, whether they be indoor or outdoor pets, is associated to a decreased prevalence in atopic dermatitis.

Is childhood wheeze and asthma in Latin America associated with poor hygiene and infection? A systematic review

Introduction

High asthma prevalence in Latin-American cities is thought to be caused by poor hygiene and infections. This contradicts the widely accepted 'hygiene hypothesis' for asthma aetiology.

Methods

Systematic review of observational studies evaluating the association between poor hygiene exposures or infections and asthma/wheeze among Latin-American children aged 4-16 years. MEDLINE, EMBASE, LILACS and CINAHL electronic databases were searched following a predefined strategy to 18 December 2017. We quantified outcomes measured and reported, assessed risk of bias and tabulated the results.

Results

Forty-five studies included: 6 cohort, 30 cross-sectional and 9 case-control studies. 26 cross-sectional studies were school-based surveys (14 of over 3000 children), whereas 5 case-control studies were hospital/health centre-based. Exposures measured and reported varied substantially between studies, and current wheeze was the most common outcome reported. Data showed selective reporting based on statistical significance (P value <0.05): 17/45 studies did not clearly describe the number of exposures measured and 15/45 studies reported on less than 50% of the exposures measured. Most exposures studied did not show an association with wheeze or asthma, except for a generally increased risk associated with acute respiratory infections in early life. Contradictory associations were observed frequently between different studies.

Conclusion

Selective reporting is common in observational studies exploring the association between environmental exposures and risk of wheeze/asthma. This, together with the use of different study outcomes (wheeze/asthma) associated with possibly distinct causal mechanisms, complicates inferences about the role of poor hygiene exposures and childhood infections in explaining asthma prevalence in Latin-American children.

Prevalence and associated factors of wheezing illnesses of children aged three to five years living in under-served settlements of the Colombo Municipal Council in Sri Lanka: a cross-sectional study

BACKGROUND

A rising trend in Sri Lanka for asthma and wheezing illness is observed with higher morbidity in younger children and a paucity of related research. 'Under-served settlements' (USS) of Colombo Municipal Council (CMC) have poor living environments conducive to childhood wheezing. The objective was to describe the prevalence and associated factors of wheezing illnesses of three to five year old children living in low-income settlements in CMC.

METHODS

A cross-sectional study was conducted on 460 three to five year old children and their caregivers using cluster sampling among residents of two randomly selected USSs of CMC. An interviewer-administered questionnaire, observation checklist and data extraction form were used in data collection. A physician's diagnosis of wheezing/whistling of the chest in their lifetime and a physician's diagnosis of wheezing/whistling within the past twelve months were considered as 'ever-wheezing illness' and 'current-wheezing illness' respectively.

RESULTS

Mean age was 3.98 years (SD = ±0.64 years). A majority were males (51.3%) and Tamils (39.8%). Prevalence of 'ever wheezing illness' and 'current wheezing illness' were 38% (95% confidence interval (CI); 33.6%-42.5%) and 21.3% (95%CI; 17.6%-25.0%), respectively. Maternal (p < 0.001) and paternal (p < 0.001) histories of wheezing, playing with soft toys in the sleeping area (p = 0.004), place of cooking combined with the living area (p = 0.03), unsatisfactory ventilation in the sleeping area (p < 0.001) were found to be significantly associated with increased 'current wheezing' through multivariate analysis in this study. Use of formula milk before six months of age (p = 0.014) was found to be protective through multivariate analysis.

CONCLUSIONS

The magnitude of wheezing illnesses among three to five year old children residing in urban low-income settlements was found to be high. Children with a history of maternal and/or paternal wheezing should be targeted for early interventions to prevent wheezing illnesses. Interventions to avoid exacerbations should focus on the indoor environmental factors that were found to be associated with wheezing illnesses.

Association of outdoor air pollution with the prevalence of asthma in children of Latin America and the Caribbean: A systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the association between asthma prevalence and outdoor air pollution in children in Latin America and the Caribbean.

DATA SOURCES

We searched studies in global and regional databases: PubMed, Scopus, LILACS and SciELO.

STUDY SELECTION

Articles following a cross-sectional design, studying children from 0 to 18 years old, and comparing the prevalence of asthma in two or more areas of LAC countries with different air pollution levels were included. The exclusion criteria comprised air pollution not related to human activities.

RESULTS

Database searches retrieved 384 records, while 20 studies were retained for qualitative and 16 for quantitative analysis, representing 48 442 children. We found a positive association, i.e. a higher prevalence of asthma in children living in a polluted environment, with pooled odds ratio (OR) of 1.34 (95% CI: 1.17-1.54). Heterogeneity between studies was moderate (I²: 68.39%), while the risk of bias was intermediate or high in 14 studies. In all the subgroup and sensitivity analyses, the pooled ORs were significant and higher than those found in the general analysis Conclusions: Our results showed that living in a polluted environment is significantly associated with children having asthma in LAC. Limitations of this study include the low number of studies performed in LAC countries, differences in methodologies and the risk of bias in individual studies.

Environmental Determinants of Bronchial Asthma among Saudi School Children in Southwestern Saudi Arabia

The aim here was to study the possible environmental and dietary determinants of asthma among school-aged children in Southwestern Saudi Arabia. In a cross-sectional study on a representative sample in Najran in Southwestern Saudi Arabia using an Arabic version of the modified ISAAC Phase III, parent-administered questionnaire data were collected. Skin prick tests (SPTs) were performed. The study included 1700 school children, out of them 468 (27.5%) were diagnosed with, cases of bronchial asthma and 20.8% (353) reported a 12-month nocturnal cough (as a proxy of severe asthma). In multivariable analysis, the study identified the following risk factors for having asthma or severe asthma: having dogs in the house, being male, being exposed to dense truck traffic on the street, using wood as a cooking fuel, conducting vigorous exercise, consuming eggs, consuming vegetables, having an allergic sensitization to dog hair, and being exposed to Cladosporium, pigweed, and Bermuda grass. On the other hand, the following food stuffs were found to be protective: seafood, fruit, and dairy products. Comprehensive school educational programs for both children and their parents should be adopted to prevent the use of wood in cooking and heating, to ensure that house pets are properly cared for, and to encourage proper dietary habits. Physicians should be informed of the patterns of allergens in order to improve asthma diagnosis and management.

IgE antibodies and urinary trimethylarsine oxide accounted for 1-7% population attributable risks for eczema in adults: USA NHANES 2005-2006

Population attributable risks from serum IgE and dust miteallergen concentrations and environmental chemicals for eczema are unclear. Therefore, it was aimed to examine serum IgE and allergen concentrations and environmental chemicals for eczema in adults and to calculate population attributable risks in a national and population-based setting. Data retrieved from the National Health and Nutrition Examination Survey, 2005-2006, was analyzed. Information on demographics and self-reported ever eczema was obtained by household interview. Bloods and urines (sub-sample) were also collected during the interview. Adults aged 20-85 were included. Statistical analyses were using chi-square test, t test, survey-weighted logistic regression modeling, and population attributable risk (PAR) estimation. Of all the included American adults (n = 4979), 310 (6.2%) reported ever eczema. Moreover, more eczema cases were observed in female adults but fewer cases in people born in Mexico. There were no significant associations observed between commonly known biomarkers (including vitamin D) and eczema or between dust mite allergens and eczema. Serum D. Farinae (PAR 1.0%), D. Pteronyssinus (PAR 1.1%), cat (PAR 1.8%), dog (PAR 1.6%), and muse (PAR 3.2%) IgE antibodies were associated with eczema. Adults with ever eczema were found to have higher levels of urinary trimethylarsine oxide concentrations (PAR 7.0%) but not other speciated arsenic concentrations. There were no clear associations between other environmental chemicals including heavy metals, phthalates, phenols, parabens, pesticides, nitrate, perchlorate, polycyclic hydrocarbons and eczema as well. Elimination of environmental risks might help delay or stop eczema up to 7% in the adult population.