Variable risk of atopic disease due to indoor fungal exposure in NHANES 2005-2006

The Social and Home Environment: Impacts of Determinants of Health on Atopic Dermatitis, Pathways Toward Solutions, and Unique Considerations for Rural and Remote North American Indigenous Populations

Disparities in environmental and social determinants of health (DOH) are associated with morbidity in atopic dermatitis (AD). The socioecological model (SEM) is a framework that can be applied to better understand how such DOH impacts patients with AD. We include a case scenario of a remote Indigenous patient reflective of real-world situations of living with AD and examine relevant impact, gaps in knowledge, and further research needs. This review highlights a variety of social and environmental exposures as important DOH which must be addressed to achieve optimal management in AD. The "rainbow model" is a modified framework to help illustrate how complex environmental and social forces impact both AD presentation and therapeutic success. However, practical applications and outcome metrics for health promotion are limited. An inter- and transdisciplinary approach is paramount to address the complex challenges associated with AD care, as well as multistakeholder approach integrating culturally-competent equitable health frameworks. This review underscores the importance of expanding the focus of AD management beyond basic science and clinical trials to recognize and address health disparities and to promote optimal health and well-being in patients with AD, and contributes a working approach to mapping the complex interventions and patient-oriented research needed using a focus on remote North American Indigenous patients affected by AD.

Association of exposure to indoor molds and dampness with allergic diseases at water-damaged dwellings in Korea

This study aims to characterize levels of molds, bacteria, and environmental pollutants, identify the associations between indoor mold and dampness exposures and childhood allergic diseases, including asthma, allergic rhinitis, atopic dermatitis, using three different exposure assessment tools. A total of 50 children with their parents who registered in Seoul and Gyeonggi-do in Korea participated in this study. We collated the information on demographic and housing characteristics, environmental conditions, and lifestyle factors using the Korean version of the International Study of Asthma and Allergies in Childhood questionnaire. We also collected environmental monitoring samples of airborne molds and bacteria, total volatile organic compounds, formaldehyde, and particulate matter less than 10 µm. We evaluated and determined water damage, hidden dampness, and mold growth in dwellings using an infrared (IR) thermal camera and field inspection. Univariate and multivariate regression analyses were performed to evaluate the associations between prevalent allergic diseases and exposure to indoor mold and dampness. Indoor mold and bacterial levels were related to the presence of water damage in dwellings, and the mean levels of indoor molds (93.4 ± 73.5 CFU/m3) and bacteria (221.5 ± 124.2 CFU/m3) in water-damaged homes were significantly higher than those for molds (82.0 ± 58.7 CFU/m3) and for bacteria (152.7 ± 82.1 CFU/m3) in non-damaged dwellings (p < 0.05). The crude odds ratios (ORs) of atopic dermatitis were associated with < 6th floor (OR = 3.80), and higher indoor mold (OR = 6.42) and bacterial levels (OR = 6.00). The crude ORs of allergic diseases, defined as a group of cases who ever suffered from two out of three allergic diseases, e.g., asthma and allergic rhinitis, and allergic rhinitis were also increased by 3.8 and 9.3 times as large, respectively, with water damage (+) determined by IR camera (p < 0.05). The adjusted OR of allergic rhinitis was significantly elevated by 10.4 times in the water-damaged dwellings after adjusting age, sex, and secondhand smoke. Therefore, a longitudinal study is needed to characterize dominant mold species using DNA/RNA-based sequencing techniques and identify a causal relationship between mold exposure and allergic diseases in the future.

Skin morbidity in Indigenous children in relation to housing conditions in remote communities in Northwestern Ontario, Canada

BACKGROUND

Elevated rates of eczema and skin infections in Canadian First Nation (FN) communities are of concern to families, community leaders and healthcare professionals.

AIM

To determine whether skin morbidity was associated with indoor environmental quality factors in Canadian FN children living in remote communities.

METHODS

We quantified indoor environmental quality (IEQ) in the homes of FN children aged < 4 years of age living in four remote communities in the Sioux Lookout region of Northwestern Ontario, Canada. We conducted a quantitative housing inspection, including measuring surface area of mould (SAM), and monitored air quality for 5 days in each home, including carbon dioxide and relative humidity and quantified endotoxin in settled floor dust. We reviewed the medical charts of participating children for skin conditions and administered a health questionnaire. Relationships between IEQ and skin infections or eczema were evaluated using multivariable regression.

RESULTS

In total, 98 children were included in the descriptive analyses, of whom 86 had complete data and were evaluated in multivariate analyses for dermatological outcomes (mean age 1.6 years). Of these 86 children, 55% had made ≥ 1 visits to the local health centre (HC) for skin and soft tissue infections and 25.5% for eczema. Unexpectedly, annualized eczema visits were inversely associated with SAM (RR = 0.14; 95% CI 0.01-0.93). There was a trend suggesting an inverse relationship between endotoxin and HC encounters for eczema and skin and soft tissue infections.

CONCLUSION

Skin infections were common in this population of FN children. IEQ did not appear to be associated with skin infections or eczema. Mould exposure appeared to be inversely associated with HC encounters for eczema, possibly related to complex microorganism-host interactions occurring early in life.

Using Sensor Data to Identify Factors Affecting Internal Air Quality within 279 Lower Income Households in Cornwall, South West of England

(1) Background: Poor air quality affects health and causes premature death and disease. Outdoor air quality has received significant attention, but there has been less focus on indoor air quality and what drives levels of diverse pollutants in the home, such as particulate matter, and the impact this has on health; (2) Methods: This study conducts analysis of cross-sectional data from the Smartline project. Analyses of data from 279 social housing properties with indoor sensor data were used to assess multiple factors that could impact levels of particulate matter. T-Tests and Anova tests were used to explore associations between elevated PM2.5 and building, household and smoking and vaping characteristics. Binary logistic regression was used to test the association between elevated particulate matter and self-reported health; (3) Results: Of the multiple potential drivers of the particulate matter investigated, smoking and vaping were significantly associated with mean PM2.5. Following multivariate analysis, only smoking remained significantly associated with higher mean concentrations. Properties in which <15 cigarettes/day were smoked were predicted to have PM2.5 concentrations 9.06 µg/m3 higher (95% CI 6.4, 12.82, p ≤ 0.001) than those in which residents were non-smokers and 11.82 µg/m3 higher (95% CI 7.67, 18.19, p ≤ 0.001) where >15 cigarettes were smoked; (4) Conclusions: A total of 25% of social housing properties in this study experienced levels of indoor PM greater than WHO guideline levels for ambient air pollution. Although there are many factors that impact air quality, in this study the main driver was smoking. This highlights the importance of targeting smoking in indoor environments in future smoking cessation and control policy and practice and of understanding how pollutants interact in the home environment. There is also a need for further research into the impact on indoor air quality of vaping, particularly due to the rise in use and uncertainty of its long-term impact.

Cutaneous dysbiosis may amplify barrier dysfunction in patients with atopic dermatitis

Atopic dermatitis (AD) is associated with cutaneous dysbiosis, barrier defects, and immune dysregulation, but the interplay between these factors needs further study. Early-onset barrier dysfunction may facilitate an innate immune response to commensal organisms and, consequently, the development of allergic sensitization. We aimed to compare the cutaneous microbiome in patients with active dermatitis with and without a history of childhood flexural dermatitis (atopic dermatitis). Next-gen Ion-Torrent deep-sequencing identified AD-associated changes in the skin bacterial microbiome ("bacteriome") and fungal microbiome ("mycobiome") of affected skin in swabs from areas of skin affected by dermatitis. Data were analyzed for diversity, abundance, and inter-kingdom correlations. Microbial interactions were assessed in biofilms using metabolic activity (XTT) assay and scanning electron microscopy (SEM), while host-pathogen interactions were determined in cultured primary keratinocytes exposed to biofilms. Increased richness and abundance of Staphylococcus, Lactococcus, and Alternaria were found in atopics. Staphylococcus and Alternaria formed robust mixed-species biofilms (based on XTT and SEM) that were resistant to antifungals/antimicrobials. Furthermore, their biofilm supernatant was capable of influencing keratinocytes biology (pro-inflammatory cytokines and structural proteins), suggesting an additive effect on AD-associated host response. In conclusion, microbial inter-kingdom and host-microbiome interactions may play a critical role in the modulation of atopic dermatitis to a greater extent than in non-atopic adults with allergic contact dermatitis.

Indoor green can modify the indoor dust microbial communities

Little is known about the potential role of indoor plants in shaping the indoor microbiota. Within the ENVIRONAGE birth cohort, we collected settled dust and performed 16S and ITS amplicon sequencing and qPCR measurements to characterize the indoor microbiota, including bacterial and fungal loads and Chao1 richness, Shannon, and Simpson diversity indices. For 155 households, we obtained information on the number of indoor plants. We performed linear regression models adjusted for several a priori chosen covariables. Overall, an increase in indoor plants and density was associated with increased microbial diversity, but not load. For example, we found an increase of 64 (95%CI:3;125) and 26 (95%CI:4;48) units of bacterial and fungal taxa richness, respectively, in households with more than three plants compared to no plants. Our results support the hypothesis that indoor plants can enrich indoor microbial diversity, while impacts on microbial loads are not obvious.

Impact of the environment on the microbiome

OBJECTIVES

This review aimed to verify indoor and outdoor pollution, host and environmental microbiome, and the impact on the health of the pediatric population.

SOURCES

A review of the literature, non-systematic, with the search for articles since 2001 in PubMed with the terms "pollution" AND "microbiome" AND "children's health" AND "COVID-19".

SUMMARY OF THE FINDINGS

Prevention of allergic diseases includes the following aspects: avoid cesarean delivery, the unnecessary overuse of antibiotics, air pollution, smoking in pregnancy and second-hand tobacco smoke, stimulate breastfeeding, soil connection, consume fresh fruits and vegetables, exercise and outdoor activities and animal contact. The children's microbiota richness and diversity decrease the risk of immune disbalance and allergic disease development.

CONCLUSIONS

Lifestyle and exposure to pollutants, both biological and non-biological, modify the host and the environment microbiome provoking an immune disbalance with inflammatory consequences and development of allergic diseases.

Species-resolved sequencing of low-biomass or degraded microbiomes using 2bRAD-M

Microbiome samples with low microbial biomass or severe DNA degradation remain challenging for amplicon-based or whole-metagenome sequencing approaches. Here, we introduce 2bRAD-M, a highly reduced and cost-effective strategy which only sequences ~ 1% of metagenome and can simultaneously produce species-level bacterial, archaeal, and fungal profiles. 2bRAD-M can accurately generate species-level taxonomic profiles for otherwise hard-to-sequence samples with merely 1 pg of total DNA, high host DNA contamination, or severely fragmented DNA from degraded samples. Tests of 2bRAD-M on various stool, skin, environmental, and clinical FFPE samples suggest a successful reconstruction of comprehensive, high-resolution microbial profiles.

Prevalence of Asthma and Its Associating Environmental Factors among 6-12-Year-Old Schoolchildren in a Metropolitan Environment-A Cross-Sectional, Questionnaire-Based Study

We aimed to evaluate the prevalence of asthma and its associating environmental factors within a 6–12-year-old population. A cross-sectional, questionnaire-based study was conducted in primary schools located in the capital of Hungary; 3836 eligible parent-reported questionnaires were evaluated. Besides the International Study of Asthma and Allergies in Childhood (ISAAC) phase three core questions for asthma, the survey also assessed various potential risk factors. We introduced the umbrella term cumulative asthma as the union of physician-diagnosed asthma and current wheezing to estimate the lifetime prevalence of asthma. Current wheezing and physician-diagnosed asthma showed a frequency of 9.5% and 6.3%, respectively. They contributed to a cumulative asthma prevalence of 12.6% among the sampled population, with a girl-boy percentage of 37.4% to 62.6%. Air-pollution and weedy areas were associated with greater risk for asthma, while a suburban residence showed lesser odds. Indoor smoking, visible mold, and keeping a dog were defined as risk factors for asthma, while the presence of plants in the bedroom and pet rodents were associated with lower odds ratios. The consumption of fast food, beverages containing additives and margarine were significantly higher in asthmatics, while we found frequent sport activity and cereal intake associated with lower odds ratios for asthma. In this urban environment, we identified an increased asthma prevalence compared to some previously published studies, but the cross-sectional design and the different methodology did not permit us to draw timeframe-dependent conclusions.

Indoor PM2.5, VOCs and asthma outcomes: A systematic review in adults and their home environments

INTRODUCTION

As the amount of time people spend indoors increases globally, exposure to indoor air pollutants has become an important public health concern. Asthma is a complex disease caused and/or exacerbated by increased exposure to diverse chemical, physical and biological exposures from multiple indoor and outdoor sources. This review aims to investigate the relationship between increased indoor PM and VOC concentrations (i.e. objectively measured) and the risk of adult asthma in higher-income countries.

METHODS

Eleven databases were systematically searched on the February 1, 2019 and again on the February 2, 2020. Articles were limited to those published since 1990. Reference lists were independently screened by three reviewers and authors were contacted to identify relevant articles. Backwards and forward citation chasing was used to identify further studies. Data were extracted from included studies meeting our eligibility criteria by three reviewers and assessed for quality using the Newcastle-Ottawa scale designed for case-control and cohort studies.

RESULTS

Twelve studies were included in a narrative synthesis. We found insufficient evidence to determine the effect of PM2.5 on asthma in the indoor home environment. However, there was strong evidence to suggest that VOCs, especially aromatic compounds, and aliphatic compounds, were associated with increased asthma symptoms.

DISCUSSION & CONCLUSION

Although no single exposure appears to be responsible for the development of asthma or its associated symptoms, the use of everyday products may be associated with increased asthma symptoms. To prevent poor health outcomes among the general population, health professionals and industry must make a concerted effort to better inform the general population of the importance of appropriate use of and storage of chemicals within the home as well as better health messaging on product labelling.

Innate Type 2 Response to Aspergillus fumigatus in a Murine Model of Atopic Dermatitis-like Skin Inflammation

BACKGROUND

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mediated by T helper type 2 (Th2) cells in acute phase. Group 2 innate lymphoid cells (ILCs) play a role in the initiation of the Th2 response. Although mold exposure is associated with the development of AD, studies on the underlying mechanisms are lacking. This study investigated whether group 2 ILCs are involved in inflammation in AD-like skin induced by Aspergillus fumigatus (Af).

METHODS

We investigated changes of group 2 ILCs population in Af-induced AD-like skin lesions. To induce AD-like skin lesions, Af extracts were applied to the dorsal skin of BALB/c and Rag1^-/- mice five times per week, with repeat exposures at 2-week intervals.

RESULTS

The clinical parameters were higher in the Af-treated group than in the control group. Histologic findings revealed epiderrmal and dermal thickening as well as eosinophil and mast cell infiltration into the skin of Af-treated mice. Populations of group 2 ILCs in the skin were also significantly higher in the Af-treated group. In addition, interleukin-33 mRNA expression was significantly higher in the skin lesions of the Af-treated mice. In the Rag1^-/- mice lacking mature lymphocytes, AD-like skin lesions were still induced by Af and ILCs depletion using an anti-CD90.2 mAb lowered the Af-induced inflammatory response.

CONCLUSIONS

Group 2 ILCs may play a role in a murine model of Af-induced AD-like skin lesions.

Household mold, pesticide use, and childhood asthma: A nationwide study in the U.S

OBJECTIVES

To investigate the associations of household mold and pesticide use with risk of childhood asthma and examine the potential effect modification by child's sex at a national level in the U.S.

METHODS

Nationally representative data were drawn from the cross-sectional 2017 and 2018 National Surveys of Children's Health. Household mold and pesticide exposures during the past 12 months and physician-diagnosed childhood asthma were assessed by standard questionnaires administered to primary caregivers. Multivariable logistic regression models were used to calculate adjusted odds ratios (aOR) for current asthma, adjusting for child, caregiver, and household covariates. We also examined potential effect modification by child's sex. Sampling weights accounted for the complex survey design.

RESULTS

Among 41,423 U.S. children in 2017-2018, the weighted prevalence of current asthma was 10.8% in household mold-exposed children, compared with 7.2% in non-exposed children (P < 0.001). After adjusting for covariates including child's obesity, children with household mold exposure compared to those with no household mold exposure had a 1.41-fold (95% CI: 1.07, 1.87) higher odds of current asthma. Associations between household mold and current asthma were pronounced among boys (aOR 1.57; 95% CI: 1.03-2.38) but not girls (aOR 1.28; 0.90-1.83; P for interaction <0.001). No significant associations were observed between household pesticide use and current asthma, after adjusting for covariates.

CONCLUSIONS

Our findings suggest that household mold is associated with current asthma among children, independent of other major risk factors including child's obesity status. Our findings may inform strategies targeting mitigation of household mold as an important indoor environment factor to address childhood asthma.

House characteristics and condition as determinants of visible mold and musty odor: Results from three New Zealand House Condition Surveys in 2005, 2010, and 2015

This study assessed associations between house characteristics and mold and musty odor, using data from three consecutive (2005, 2010, and 2015) New Zealand House Condition Surveys, involving a total of 1616 timber-framed houses. Mold, musty odor, and house characteristics were assessed by independent building inspectors. We used multivariate logistic regression analyses mutually adjusted for other house characteristics for each survey separately. Positive and independent associations were found with tenure, ventilation, insulation, and envelope condition for both mold in living and bedrooms and musty odor. In particular, we found significant dose-response associations with envelope condition, ventilation, and insulation. Odds of mold increased 2.4-15.9 times (across surveys) in houses with the worst building envelope condition (BEC; p < 0.05-0.001 for trend); optimal ventilation reduced the risk of mold by 60% and the risk of musty odor by 70%-90% (p < 0.01 for trend). Other factors associated with mold and musty odor included: tenure, with an approximate doubling of odds of mold across surveys; and insulation with consistent dose-response patterns in all outcomes and surveys tested (p < 0.05 for trend in two surveys with mold and one survey for odor). In conclusion, this study showed the importance of BEC, ventilation, and insulation to avoiding harmful damp-related exposures.

Domestic Risk Factors for Atopic and non-Atopic Asthma in First Nations Children Living in Saskatchewan, Canada

Both allergic and non-allergic asthma phenotypes are thought to vary by specific housing and other indoor environmental conditions. This study evaluated risk factors for allergic asthma phenotypes in First Nation children, an understudied Canadian population with recognized increased respiratory morbidity. We conducted a cross-sectional survey with a clinical component to assess the respiratory health of 351 school-age children living on two rural reserve communities. Asthma was defined as parental report of physician diagnosed asthma or a report of wheeze in the past 12 months. Atopy was determined by a ≥ 3-mm wheal response to any of six respiratory allergens upon skin prick testing (SPT). Important domestic and personal characteristics evaluated included damp housing conditions, household heating, respiratory infections and passive smoking exposure. Asthma and atopy prevalence were 17.4% and 17.1%, respectively. Of those with asthma, 21.1% were atopic. We performed multivariate multinomial logistic regression modelling with three outcomes: non-atopic asthma, atopic asthma and no asthma for 280 children who underwent SPT. After adjusting for potential confounders, children with atopic asthma were more likely to be obese and to live in homes with either damage due to dampness (p < 0.05) or signs of mildew/mold (p = 0.06). Both natural gas home heating and a history of respiratory related infections were associated with non-atopic asthma (p < 0.01). Domestic risk factors for asthma appear to vary by atopic status in First Nations children. Determining asthma phenotypes could be useful in environmental management of asthma in this population.

Household energy efficiency and health: Area-level analysis of hospital admissions in England

INTRODUCTION

Fuel poverty affects up to 35% of European homes, which represents a significant burden on society and healthcare systems. Draught proofing homes to prevent heat loss, improved glazing, insulation and heating (energy efficiency measures) can make more homes more affordable to heat. This has prompted significant investment in energy efficiency upgrades for around 40% of UK households to reduce the impact of fuel poverty. Despite some inconsistent evidence, household energy efficiency interventions can improve cardiovascular and respiratory health outcomes. However, the health benefits of these interventions have not been fully explored; this is the focus of this study.

METHODS

In this cross sectional ecological study, we conducted two sets of analyses at different spatial resolution to explore population data on housing energy efficiency measures and hospital admissions at the area-level (counts grouped over a 3-year period). Housing data were obtained from three data sets covering housing across England (Household Energy Efficiency Database), Energy Performance Certificate (EPC) and, in the South West of England, the Devon Home Analytics Portal. These databases provided data aggregated to Lower Area Super Output Area and postcode level (Home Analytics Portal only). These datasets provided measures of both state (e.g. EPC ratings) and intervention (e.g. number of boiler replacements), aggregated spatially and temporally to enable cross-sectional analyses with health outcome data. Hospital admissions for adult (over 18 years) asthma, chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD) were obtained from the Hospital Episode Statistics database for the national (1st April 2011 to 31st March 2014) and Devon, South West of England (1st April 2014 to 31st March 2017) analyses. Descriptive statistics and regression models were used to describe the associations between small area household energy efficiency measures and hospital admissions. Three main analyses were undertaken to investigate the relationships between; 1) household energy efficiency improvements (i.e. improved glazing, insulation and boiler upgrades); 2) higher levels of energy efficiency ratings (measured by Energy Performance Certificate ratings); 3) energy efficiency improvements and ratings (i.e. physical improvements and rating assessed by the Standard Assessment Procedure) and hospital admissions.

RESULTS

In the national analyses, household energy performance certificate ratings ranged from 37 to 83 (mean 61.98; Standard Deviation 5.24). There were a total of 312,837 emergency admissions for asthma, 587,770 for COPD and 839,416 for CVD. While analyses for individual energy efficiency metrics (i.e. boiler upgrades, draught proofing, glazing, loft and wall insulation) were mixed; a unit increase in mean energy performance rating was associated with increases of around 0.5% in asthma and CVD admissions, and 1% higher COPD admission rates. Admission rates were also influenced by the type of dwelling, tenure status (e.g. home owner versus renting), living in a rural area, and minimum winter temperature.

DISCUSSION

Despite a range of limitations and some mixed and contrasting findings across the national and local analyses, there was some evidence that areas with more energy efficiency improvements resulted in higher admission rates for respiratory and cardiovascular diseases. This builds on existing evidence highlighting the complex relationships between health and housing. While energy efficiency measures can improve health outcomes (especially when targeting those with chronic respiratory illness), reduced household ventilation rates can impact indoor air quality for example and increase the risk of diseases such as asthma. Alternatively, these findings could be due to the ecological study design, reverse causality, or the non-detection of more vulnerable subpopulations, as well as the targeting of areas with poor housing stock, low income households, and the lack of "whole house approaches" when retrofitting the existing housing stock.

CONCLUSION

To be sustainable, household energy efficiency policies and resulting interventions must account for whole house approaches (i.e. consideration of the whole house and occupant lifestyles). These must consider more alternative 'greener' and more sustainable measures, which are capable of accounting for variable lifestyles, as well as the need for adequate heating and ventilation. Larger natural experiments and more complex modelling are needed to further investigate the impact of ongoing dramatic changes in the housing stock and health.

STUDY IMPLICATIONS

This study supports the need for more holistic approaches to delivering healthier indoor environments, which must consider a dynamic and complex system with multiple interactions between a range of interrelated factors. These need to consider the drivers and pressures (e.g. quality of the built environment and resident behaviours) resulting in environmental exposures and adverse health outcomes.

Asthma, allergic rhinitis and eczema among parents of preschool children in relation to climate, and dampness and mold in dwellings in China

The main aim was to study associations between asthma, allergic rhinitis and eczema among adults across China and dampness and mold at home. Young adults (N = 40,279) in eight cities in China answered a questionnaire in 2010-2012 (response rate 75.0%). Data on asthma, allergic rhinitis, eczema and the home environment was assessed by the questionnaire. Climate data was obtained from China Meteorological Administration and the website of Weather Underground. Health associations were analyzed by two-level logistic regression models, adjusting for covariates. Totally 1.6% had asthma, 6.6% allergic rhinitis and 2.2% eczema. Mold odor was associated with asthma (OR = 1.90) and allergic rhinitis (OR = 1.25-1.44). Window pane condensation in winter was associated with asthma (OR = 1.39), allergic rhinitis (OR = 1.26-1.58) and eczema (OR = 1.36-1.77). Presence of mold spots or damp stains was related to asthma (OR = 1.58-2.49), allergic rhinitis (OR = 1.35-1.76) and eczema (OR = 1.47-1.70). Water damage was related to asthma (OR = 1.69-1.82), allergic rhinitis (OR = 1.40-1.45) and eczema (OR = 1.44-1.96). Damp bed clothing was related to asthma (OR = 1.23), allergic rhinitis (OR = 1.23) and eczema (OR = 1.35). A higher dampness score was associated with increased odds ratios for diseases. Those living in older buildings had more asthma (OR = 1.39-1.76) and allergic rhinitis (OR = 1.16-1.21). Those living in suburban or rural areas had less asthma, allergic rhinitis and eczema as compared to those living in urban areas (OR values from 0.24 to 0.66). Stronger health associations with dampness and mold were found in southern China and in newer buildings (constructed after 2005). In conclusion, dampness and mold at home can be risk factors for asthma, allergic rhinitis and eczema among adults in China. Living in older buildings can be risk factors for asthma or allergic rhinitis while living in less urbanized areas can be protective.

Exposure to Indoor Mouldy Odour Increases the Risk of Asthma in Older Adults Living in Social Housing

Background: Indoor dampness is thought to affect around 16% of European homes. It is generally accepted that increased exposure to indoor dampness and mould contamination (e.g., spores and hyphae) increases the risk of developing and/or exacerbating asthma. Around 30% of people in the Western world have an allergic disease (e.g., allergy, wheeze and asthma). The role of indoor mould contamination in the risk of allergic diseases in older adults is yet to be fully explored. This is of interest because older people spend more time indoors, as well as facing health issues due to the ageing process, and may be at greater risk of developing and/or exacerbating asthma as a result of indoor dampness. Methods: Face-to-face questionnaires were carried out with 302 participants residing in social housing properties located in South West England. Self-reported demographic, mould contamination (i.e., presence of mould growth and mouldy odour) and health information was linked with the asset management records (e.g., building type, age and levels of maintenance). Multivariate logistic regression was used to calculate the odd ratios and confidence intervals of developing and/or exacerbating asthma, wheeze and allergy with exposure to reported indoor mould contamination. We adjusted for a range of factors that may affect asthma outcomes, which include age, sex, current smoking, presence of pets, education, and building type and age. To assess the role of mould contamination in older adults, we compared younger adults to those aged over 50 years. Results: Doctor-diagnosed adult asthma was reported by 26% of respondents, 34% had current wheeze while 18% had allergies. Asthma was common among subjects exposed to reported visible mould (32%) and reported mouldy odour (42%). Exposure to visible mould growth and mouldy odour were risk factors for asthma, but not for wheeze or allergy. Exposure to mouldy odour increased the risk of asthma in adults over the age of 50 years (odds ratio (OR) 2.4, 95% confidence interval (CI) 1.10–5.34) and the risk was higher for females than for males (OR 3.5, 95% CI 1.37–9.08). These associations were modified by a range of built environment characteristics. Conclusions: We found that older adults living in social (public) housing properties, specifically women, may be at higher risk of asthma when exposed to mouldy odour, which has a number of implications for policy makers and practitioners working in the health and housing sector. Additional measures should be put in place to protect older people living in social housing against indoor damp and mould contamination.

Sex-moderated interactions between IL4/IL13 pathway genes and prenatal environment on cord blood IgE levels

BACKGROUND

Elevated cord blood IgE (cIgE), a predictor of atopic diseases, is influenced by genetic and environmental factors. However, gene-environment interactions on cIgE elevation and their difference by sex remain largely unexplored.

OBJECTIVE

This study aimed to determine whether there are sex-moderated interactions between genetic variants in the IL4/IL13 pathway and prenatal environments on cIgE elevation.

METHODS

Comprehensive information on environmental tobacco smoke (ETS), home dampness (indexed by combining mildewy odour, visible mould and water stamp on the wall) and other household environments was obtained using a structured questionnaire during the third trimester of pregnancy in 1107 full-term newborns. The cord blood was collected for measuring cIgE levels, with elevation defined as ≥0.5 IU/mL, and for genotyping of five single nucleotide polymorphisms of three candidate genes (IL-13 rs1800925, rs20541, rs848, IL-4 rs2243250 and STAT6 rs324011).

RESULTS

Gene-environment interactions on cIgE elevation were observed in male but not female newborns, including those between ETS and IL13 rs20541, between home dampness and STAT6 rs324011, and between composite environmental exposure (combined ETS and the three home dampness indices) and STAT6 rs324011 (P for interaction = 0.03, 0.006, and 0.001, respectively). Male newborns carrying STAT6 rs324011 CT or TT genotype manifested with a significant dose-response association of the composite environmental exposure with cIgE elevation.

CONCLUSION AND CLINICAL RELEVANCE

Sex moderates the gene-environment interactions involving IL4/IL13 pathway genes and prenatal household environments on cIgE elevation. The absence of prenatal exposure to ETS and home dampness in male neonates carrying the STAT6 rs324011 CT or TT genotype is least likely associated with cIgE elevation.

Making the Case for "Whole System" Approaches: Integrating Public Health and Housing

Housing conditions have been an enduring focus for public health activity throughout the modern public health era. However, the nature of the housing and health challenge has changed in response to an evolution in the understanding of the diverse factors influencing public health. Today, the traditional public health emphasis on the type and quality of housing merges with other wider determinants of health. These include the neighbourhood, community, and "place" where a house is located, but also the policies which make access to a healthy house possible and affordable for everyone. Encouragingly, these approaches to policy and action on housing have the potential to contribute to the "triple win" of health and well-being, equity, and environmental sustainability. However, more effective housing policies (and in public health in general) that adopt more systemic approaches to addressing the complex interactions between health, housing, and wider environment are needed. This paper illustrates some of the key components of the housing and health challenge in developed countries, and presents a conceptual model to co-ordinate activities that can deliver the "triple win." This is achieved by offering a perspective on how to navigate more effectively, inclusively and across sectors when identifying sustainable housing interventions.

Bedroom Allergen Exposure Beyond House Dust Mites

PURPOSE OF REVIEW

The review provides insight into recent findings on bedroom allergen exposures, primarily focusing on pet, pest, and fungal exposures.

RECENT FINDINGS

Large-scale studies and improved exposure assessment technologies, including measurement of airborne allergens and of multiple allergens simultaneously, have extended our understanding of indoor allergen exposures and their impact on allergic disease. Practical, streamlined methods for exposure reduction have shown promise in some settings, and potential protective effects of early-life exposures have been further elucidated through the investigation of specific bacterial taxa. Advances in molecular allergology have yielded novel data on sensitization profiles and cross-reactivity. The role of indoor allergen exposures in allergic disease is complex and remains incompletely understood. Advancing our knowledge of various co-exposures, including the environmental and host microbiome, that interact with allergens in early life will be crucial for the development of efficacious interventions to reduce the substantial economic and social burden of allergic diseases including asthma.

[Non-allergenic impact of indoor mold exposure]

The proportion of moldy housing in France is around 20%. It is not simple to establish that a health impact of mold is not allergic, because the identification of allergy is itself difficult. Moreover, exposure to molds and their metabolites may have a protective effect. Non-allergic health impacts may occur due to the multiple aerocontaminants found in damp or mold-containing dwellings: glucans, microbial volatile organic compounds, mycotoxins, bacteria and endotoxins. The heath impacts of indoor mold have been addressed by numerous toxicologic and epidemiologic investigations, the results of which have been summarized in three notable reports. These conclude that mold exposure is linked to a risk of ENT and bronchial symptoms, both the genesis and exacerbation of asthma and, lastly, hypersensitivity pneumonitis. Finally, other studies highlight the protective role of fungal metabolites with respect to asthma and allergy. Pulmonologists should be aware of these data, which can be useful in clinical practice and also in legal work.

Association of Infant Eczema with Childhood and Adult Asthma: Analysis of Data from the 1958 Birth Cohort Study

The influence of early life exposures on later life disease has for some time provided clues to modifiable risk factors of disease. The “atopic march” is thought to play a role in the progression of allergic diseases and may offer an opportunity to lower asthma’s health and socioeconomic burden, although evidence remains controversial. We aimed to examine the relationship between early life eczema and asthma later in life. Using the National Child Development Study, we examined infant eczema and childhood and adult asthma. Data related to asthma or wheezing bronchitis were available for 13,503 (73%; 95% CI 72–74), 11,503 (61%; 95% CI 60–61), 12,524 (68%; 95% CI 67–69), 11,194 (60%; 95% CI 60–60), 9377 (51%; 95% CI 51–51), and 9760 (53%; 95% CI 52–53) subjects at ages 11, 16, 23, 33, 44, and 50 years, respectively. Logistic regression models were fitted to examine each wave separately before and after adjusting for a range of potential confounders. Generalised estimating equation (GEE) methods were undertaken to examine the associations after pooling all data from questionnaires. The prevalence of self-reported asthma in those that had previously reported infant eczema ranged from 1.0%; 95% CI 0.9–1.4 (age 44 years) to 2.2%; 95% CI 2.1–2.3 (age 33 years). Participants with infant eczema had a 2–3-fold increased risk of reporting asthma in childhood and adulthood; this was 1.6 times at age 44 years when using spirometry measures. Similar effect sizes were observed in the GEE models when considering all participants (OR 2.9; 95% CI 2.6–3.2). Childhood and adult asthma were consistently associated with infant eczema both by using the self-reported data and lung measures.

Indoor mould exposure, asthma and rhinitis: findings from systematic reviews and recent longitudinal studies

Starting from the Institute of Medicine (IOM) and World Health Organization (WHO) reports, this review provides an overview of the literature published from 2006 to 2017 on the associations between indoor mould exposure and asthma and rhinitis separately in children and adults with a focus on longitudinal epidemiological studies.A systematic search of peer-reviewed literature was performed, including systematic reviews and meta-analyses, longitudinal, incident case-control and panel studies. 61 publications were identified reporting visible mould or mould odour or quantitative assessment of culturable fungi or mould species.In children, visible mould and mould odour were associated with the development and exacerbations of asthma, providing sufficient evidence of a causal relationship. Results from population-based studies in adults were too few and divergent to conclude at more than a limited level of evidence. Exposure to mould in a work building was associated with the incidence and exacerbations of occupational asthma, and we concluded at a sufficient evidence for an association. Systematic reviews, meta-analyses and longitudinal studies on the relationships between mould exposure and allergic rhinitis provide sufficient evidence of an association.This review extended the conclusions of the IOM and WHO reports, and highlighted the need for further longitudinal studies on asthma in adults, and on rhinitis.

Association Between Hay Fever and High Myopia in United States Adolescents and Adults

OBJECTIVES

To investigate the relationship between hay fever and refractive error in a representative sample of adolescents and adults in the United States.

METHODS

This cross-sectional study included 5,744 participants aged ≥12 years from the 2005 to 2006 National Health and Nutrition Examination Survey who participated in the allergy questionnaire, completed objective refraction and keratometry in both eyes, and had immunoglobulin E (IgE) serology. The primary predictor variable, refractive error, was classified as emmetropia (-0.99 to +0.99 diopters [D]), low myopia (-1.00 to -2.99 D), moderate myopia (-3.00 to -5.99 D), high myopia (≥-6.00 D), or hyperopia (≥1.00 D). Covariates included age, gender, race, asthma, eczema, total serum IgE ≥120 kU/L, corneal steepness, and corneal astigmatism. The primary outcome was hay fever.

RESULTS

The study population's mean age was 41.7 years; 48.8% of subjects were men and 51.2% were women. The prevalence of hay fever was 12.1% overall. High myopes had 2.7 times higher odds of hay fever compared to emmetropes (OR 2.67, CI, 1.57-4.51, P=0.001), which was independent of demographics, atopic conditions, IgE serology, and keratometry measurements.

CONCLUSIONS

The association between hay fever and high myopia identified in this large cross-sectional study remains speculative and was not mediated through corneal steepness or corneal astigmatism. Further prospective studies may help elucidate the directionality of the association between hay fever and high myopia.

Environmental determinants of allergy and asthma in early life

Allergic disease prevalence has increased significantly in recent decades. Primary prevention efforts are being guided by study of the exposome (or collective environmental exposures beginning during the prenatal period) to identify modifiable factors that affect allergic disease risk. In this review we explore the evidence supporting a relationship between key components of the external exposome in the prenatal and early-life periods and their effect on atopy development focused on microbial, allergen, and air pollution exposures. The abundance and diversity of microbial exposures during the first months and years of life have been linked with risk of allergic sensitization and disease. Indoor environmental allergen exposure during early life can also affect disease development, depending on the allergen type, dose, and timing of exposure. Recent evidence supports the role of ambient air pollution in allergic disease inception. The lack of clarity in the literature surrounding the relationship between environment and atopy reflects the complex interplay between cumulative environmental factors and genetic susceptibility, such that no one factor dictates disease development in all subjects. Understanding the effect of the summation of environmental exposures throughout a child's development is needed to identify cost-effective interventions that reduce atopy risk in children.

Fungal Exposure and Asthma: IgE and Non-IgE-Mediated Mechanisms

Fungi are ubiquitous in indoor and outdoor environments and have been associated with respiratory disease including childhood and adult asthma. A growing body of evidence from human and animal studies has revealed a link between fungal exposure, especially indoor fungal exposure, with asthma initiation, persistence, and exacerbation. Despite the overwhelming evidence linking mold exposure and asthma, the mechanistic basis for the association has remained elusive. It is now clear that fungi need not be intact to impart negative health effects. Fungal components and fungal fragments are biologically active and contribute to asthma development and severity. Recent mechanistic studies have demonstrated that fungi are potent immunomodulators and have powerful effects on asthma independent of their potential to act as antigens. This paper will review the connection between fungal exposure and asthma with a focus on the immunological mechanisms underlying this relationship.

Mold and dampness exposure and allergic outcomes from birth to adolescence: data from the BAMSE cohort

BACKGROUND

Exposure to moldy or damp indoor environments is associated with allergic disease in young children, but it is unclear whether the effects persist to adolescence. Our objective was to assess whether exposure to mold or dampness during infancy increases the risk of asthma, rhinitis, or IgE sensitization in children followed from birth to 16 years of age.

METHODS

We collected questionnaire derived reports of mold or dampness indicators and allergic outcomes from 3798 children in a Swedish birth cohort (BAMSE). Sensitization was assessed from blood samples in 3293 children. Longitudinal associations between prevalent asthma, rhinitis, and IgE sensitization and mold or dampness indicators were assessed using generalized estimating equations.

RESULTS

Exposure to any mold or dampness indicator was associated with asthma up to 16 years of age (OR 1.31; 95% CI 1.08-1.59), while exposure to mold odor (OR 1.29; 95% CI 1.03-1.62) and visible mold (OR 1.28; 95% CI 1.04-1.58) were associated with rhinitis. Increased risks were observed for nonallergic asthma (OR 1.80; 95% CI 1.27-2.55) and rhinitis (OR 1.41; 95% CI 1.03-1.93). No association was observed between mold or dampness indicators and IgE sensitization. Exposure to any mold or dampness indicator was associated with persistent asthma (OR 1.73; 95% CI 1.20-2.50), but not with early-transient or late-onset asthma.

CONCLUSION

Exposure to mold or dampness during infancy increased the risk of asthma and rhinitis up to 16 years of age, particularly for nonallergic disease. Early exposure to mold or dampness appeared particularly associated with persistent asthma through adolescence.

A cross-sectional study into the correlation of common household risk factors and allergic rhinitis in Taiwan's tropical environment

OBJECTIVE

To discuss the effect of lesser-known potential risk factors, such as bedroom showers, on the prevalence of allergic rhinitis.

METHOD

A cross-sectional, population-based study was performed using both survey and fungal culturing in southern Taiwan. There were 998 participants enrolled in the survey, and 513 sets of fungal culture obtained. With score for allergic rhinitis (SFAR) more than 7, the patient was defined to have allergic rhinitis. Risks of allergic rhinitis were calculated as odds ratios for various predicted risk factors by logistic regression. Correlation between predicted risk factors and fungal level were examined with linear regression.

RESULTS

The adjusted odds ratio of frequently using bedroom shower to having allergic rhinitis was 1.572 (95% confidence interval: 1.090-2.265), and 0.962 for people with older age to have AR (95% confidence interval: 0.949-0.976). As to the 24-hour fungal level, the standardized coefficient was 0.254 for frequent use of bedroom shower, and 0.106 for window open hours.

CONCLUSIONS

Use of bedroom shower is a potential risk factor for allergic rhinitis development.

Indoor allergen exposure and asthma outcomes

PURPOSE OF REVIEW

The aim of the present review is to discuss updates on research regarding the relationship between indoor allergen exposure and childhood asthma with a focus on clinical effects, locations of exposure, and novel treatments.

RECENT FINDINGS

Recent data continue to demonstrate that early life sensitization to indoor allergens is a predictor of asthma development later in life. Furthermore, avoidance of exposure to these allergens continues to be important especially given that the vast majority of children with asthma are sensitized to at least one indoor allergen. New research suggests that mouse allergen, more so than cockroach allergen, may be the most relevant urban allergen. Recent evidence reminds us that children are exposed to clinically important levels of indoor allergens in locations away from their home, such as schools and daycare centers. Exposure to increased levels of indoor mold in childhood has been associated with asthma development and exacerbation of current asthma; however, emerging evidence suggests that early exposure to higher fungal diversity may actually be protective for asthma development. Novel treatments have been developed that target TH2 pathways thus decreasing asthmatic responses to allergens. These therapies show promise for the treatment of severe allergic asthma refractory to avoidance strategies and standard therapies.

SUMMARY

Understanding the relationship between indoor allergens and asthma outcomes is a constantly evolving study of timing, location, and amount of exposure.

Exposure to mould allergens and rhinoconjunctivitis in Korean children

BACKGROUND

Although rhinitis is the most common allergic disease in children, few studies have explored the causal relationships between mould allergens and rhinitis. Thus, this study aimed to identify factors, especially prior exposure to mould allergens, related to rhinitis and rhinoconjunctivitis in Korean children.

METHODS

Subjects in this study were 12- to 13-year-old children from 40 national middle schools who were participants of the International Study of Asthma and Allergies in Childhood (ISAAC) study in Korea. A total of 3852 children who completed the ISAAC questionnaire in 2010 and underwent a skin prick test (SPT) and blood test were enrolled in this study.

RESULTS

The prevalence of symptoms suggestive of rhinitis or rhinoconjunctivitis in last 12 months was 42.7% and 19.4%, respectively. A parental history of allergies (OR = 2.03, 95% CI = 1.75-2.35; OR = 2.55, 95% CI = 2.13-3.06), visible mould or dampness (OR = 1.28, 95% CI = 1.09-1.51; OR = 1.23, 95% CI = 1.00-1.51), previous exposure to mould allergens (OR = 4.53, 95% CI = 2.32-8.84; OR = 4.98, 95% CI = 2.43-10.20), total IgE levels ≥78 kU/l (OR = 1.44, 95% CI = 1.22-1.69; OR = 1.99, 95% CI = 1.60-2.48) were risk factors for rhinitis and rhinoconjunctivitis.

CONCLUSIONS

This study suggested that previous exposure to mould allergens more influenced rhinitis and rhinoconjunctivitis than visible mould or dampness, and that total IgE levels of ≥78 kU/l, which was the criterion suggested in a study of Asian children, were risk factors for rhinitis diseases.

Indoor Fungal Exposure and Allergic Respiratory Disease

A gathering body of evidence has repeatedly revealed associations between indoor fungi and initiation, promotion, and exacerbation of allergic respiratory disease. The relationship between the exposure and outcome are complicated by the difficulties in measuring both exposure and outcome, the multifactorial nature of the disease, and the wide range of potential confounders. New technologies are becoming available that may enable better measurement of exposure and tighter case definitions so as to build more confidence in the associations discovered. The growing strength of the evidence base will aid the design of future public health interventions and generate new hypotheses on the cause of the rapid increase in allergic respiratory disease prevalence.

The relationship between environmental relative moldiness index values and asthma

Indoor mold exposures have been qualitatively linked to asthma for more than 25 years. Our goal has been to turn this qualitative link into a quantitative assessment of asthma risk from mold exposures as estimated by the home's environmental relative moldiness index (ERMI) value. The home's ERMI value is derived from the quantitative PCR analysis of 36 molds in a dust sample. Six epidemiological studies of the relationship between ERMI values and asthma, in cities across the U.S., showed that both children and adults with asthma were living in homes with significantly higher ERMI values than the control or comparison homes. Based on these six studies, the accuracy of the ERMI value's link to occupant asthma was analyzed using receiver operating characteristic (ROC) curve and area under the curve (AUC) statistical analysis. The AUC was 0.69 which places the test accuracy in the "fair to good" range for a medical diagnostic test. A logistic regression analysis of the six studies was performed to generate an equation that can be used to predict occupant asthma at specific ERMI values. The ERMI metric may be a useful tool to link the quantification of mold contamination in U.S. homes to some asthma health effects.

Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature.