Atopy and allergic respiratory disease in rural Poland before and after accession to the European Union

Early Origins of Asthma and Allergies: Clues From Studies in China

Asthma and allergies have emerged as some of the most common chronic diseases, particularly in developed countries. Epidemiological studies have consistently demonstrated that children growing up in farming/rural environments are less likely to develop these conditions. Over the past three decades, China has experienced unprecedented economic development and urbanisation, accompanied by a rapid rise in the prevalence of allergic disorders. Despite the substantial number of affected individuals, allergy management in China remains inconsistent and often inadequate, compounded by variations in diagnostic criteria and limited healthcare access in less developed regions. Furthermore, the vast population, regional disparities, and methodological inconsistencies in data collection have hindered the acquisition of comprehensive, large-scale epidemiological data. This review examines the factors contributing to asthma and allergies from their early origins, focusing on modifiable factors from a specific perspective of China. Factors related to traditional lifestyle, such as early-life exposure to agricultural farming and poultry, diverse dietary patterns, and early introduction of allergenic foods, appear to offer protection against allergies. Conversely, exposure to open-fire cooking, incense burning, tobacco smoke, as well as early-life antibiotic use and perinatal factors like Caesarean section delivery and prematurity may represent potential risks. A clear understanding of the role of these factors would pave the way for developing effective interventions to mitigate the substantial health and socioeconomic burdens associated with asthma and allergies.

Multi-omics in Allergic Rhinitis: Mechanism Dissection and Precision Medicine

Allergic rhinitis (AR) is a common chronic inflammatory airway disease caused by inhaled allergens, and its prevalence has increased in recent decades. AR not only causes nasal leakage, itchy nose, nasal congestion, sneezing, and allergic conjunctivitis but also induces asthma, as well as sleep disorders, anxiety, depression, memory loss, and other phenomena that seriously affect the patient's ability to study and work, lower their quality of life, and burden society. The current methods used to diagnose and treat AR are still far from ideal. Multi-omics technology can be used to comprehensively and systematically analyze the differentially expressed DNA, RNA, proteins, and metabolites and their biological functions in patients with AR. These capabilities allow for an in-depth understanding of the intrinsic pathogenic mechanism of AR, the ability to explore key cells and molecules that drive its progression, and to design personalized treatment for AR. This article summarizes the progress made in studying AR by use of genomics, epigenomics, transcriptomics, proteomics, metabolomics, and microbiomics in order to illustrate the important role of multi-omics technologies in facilitating the precise diagnosis and treatment of AR.

Genomic attributes of airway commensal bacteria and mucosa

Microbial communities at the airway mucosal barrier are conserved and highly ordered, in likelihood reflecting co-evolution with human host factors. Freed of selection to digest nutrients, the airway microbiome underpins cognate management of mucosal immunity and pathogen resistance. We show here the initial results of systematic culture and whole-genome sequencing of the thoracic airway bacteria, identifying 52 novel species amongst 126 organisms that constitute 75% of commensals typically present in heathy individuals. Clinically relevant genes encode antimicrobial synthesis, adhesion and biofilm formation, immune modulation, iron utilisation, nitrous oxide (NO) metabolism and sphingolipid signalling. Using whole-genome content we identify dysbiotic features that may influence asthma and chronic obstructive pulmonary disease. We match isolate gene content to transcripts and metabolites expressed late in airway epithelial differentiation, identifying pathways to sustain host interactions with microbiota. Our results provide a systematic basis for decrypting interactions between commensals, pathogens, and mucosa in lung diseases of global significance.

Exposure to farm environment and its correlations with total IgE, IL-13, and IL-33 serum levels in patients with atopy and asthma

BACKGROUND

The aim of the study was to evaluate total immunoglobulin E (IgE), IL-13, and IL-33 serum level in people with bronchial asthma and atopy, and in healthy control group depending on their exposure to farm animals currently and in the first year of life.

METHODS

The study included 174 individuals living in rural areas and in a small town. Standardized questions from the International Study of Asthma and Allergy in Childhood and The European Community Respiratory Health Survey (ECRHS) questionnaires were used to define asthma. Atopic status was verified by skin prick tests. Rural exposure including contact with livestock was verified by adequate questionnaire. Total serum IgE, IL-13, and IL-33 levels were assessed by ELISA (enzyme-linked immunosorbent assay) tests.

RESULTS

Participants with atopy and bronchial asthma were characterized by high level of immunoglobulin E. Tendency to lower serum IgE level was observed among people reporting present contact with farm animals. Also, among those having contact with livestock in their first year of life, the analogous tendency was noticed. No difference in serum IL-13 levels in participants with asthma and atopy, and controls was observed, and there was no effect of exposure on farm animals on the concentration of IL-13. The highest IL-33 level was found in the atopic group, and the lowest in the control group. Participants currently exposed to farm animals were predisposed to have lower IL-33 serum level.

CONCLUSION

Exposure of farm animals currently and in first year of life may result in a lower level of total IgE. Correlation between IL-13 and IL-33 serum levels and contact with livestock was not confirmed.

TLR Signaling Pathway Gene Polymorphisms, Gene-Gene and Gene-Environment Interactions in Allergic Rhinitis

Background

Allergic rhinitis (AR) is a nasal inflammatory disease resulting from a complex interplay between genetic and environmental factors. The association between Toll-like receptor (TLR) signaling pathway and environmental factors in AR pathogenesis remains to be explored. This study aims to assess the genetic association of AR with single nucleotide polymorphisms (SNPs) in TLR signaling pathway, and investigate the roles of gene–gene and gene–environment interactions in AR.

Methods

A total of 452 AR patients and 495 healthy controls from eastern China were enrolled in this hospital-based case–control study. We evaluated putatively functional genetic polymorphisms in TLR2, TLR4 and CD14 genes for their association with susceptibility to AR and related clinical phenotypes. Interactions between environmental factors (such as traffic pollution, residence, pet keeping) and polymorphisms with AR were examined using logistic regression. Models were stratified by genotype and interaction terms, and tested for the significance of gene–gene and gene–environment interactions.

Results

In the single-locus analysis, two SNPs in CD14, rs2563298 (A/C) and rs2569191 (C/T) were associated with a significantly decreased risk of AR. Compared with the GG genotype, the GT and GT/TT genotypes of TLR2 rs7656411 (G/T) were associated with a significantly increased risk of AR. Gene–gene interactions (eg, TLR2 rs7656411, TLR4 rs1927914, and CD14 rs2563298) was associated with AR. Gene–environment interactions (eg, TLR4 or CD14 polymorphisms and certain environmental exposures) were found in AR cases, but they were not significant after Bonferroni correction.

Conclusion

The genetic polymorphisms of TLR2 and CD14 and gene–gene interactions in TLR signaling pathway were associated with susceptibility to AR in this Han Chinese population. However, the present results were limited to support the association between gene–environment interactions and AR.

Worldwide prevalence of rhinitis in adults: A review of definitions and temporal evolution

Introduction

Objective

Methods

Results

Conclusions

Associations of early-life pet ownership with asthma and allergic sensitization: a meta-analysis of >77,000 children from the EU Child Cohort Network

BACKGROUND

Studies examining associations of early-life cat and dog ownership with childhood asthma have reported inconsistent results. Several factors could explain these inconsistencies, including type of pet, timing and degree of exposure.

OBJECTIVE

To study associations of early-life cat and dog ownership with school-age asthma, including the role of type (cat versus dog), timing (never, prenatal or early childhood) and degree (number) of ownership, and the role of allergic sensitisation.

METHODS

We used harmonised data from 77,434 mother-child dyads aged 5-11 years from nine birth cohorts in the EU Child Cohort Network. Associations were examined through the DataSHIELD platform using adjusted logistic regression models, fitted separately for each cohort and combined using random-effects meta-analysis.

RESULTS

Early-life cat and dog ownership ranged between 12-45% and 7-47% respectively, and prevalence of asthma between 2-20%. There was no overall association between either cat or dog ownership and asthma (OR: 0.97 (95% CI: 0.87-1.09) and 0.92 (0.85-1.01), respectively). Timing and degree of ownership did not strongly influence associations. Cat and dog ownership were also not associated with cat- and dog-specific allergic sensitisation (OR: 0.92 (0.75-1.13) and 0.93 (0.57-1.54), respectively). However, cat- and dog-specific allergic sensitisation were strongly associated with school-age asthma (OR: 6.69 (4.91-9.10) and 5.98 (3.14-11.36), respectively). There was also some indication of an interaction between ownership and sensitisation, suggesting that ownership may exacerbate the risks associated with pet-specific sensitisation, but offer some protection against asthma in the absence of sensitisation.

CONCLUSION

Our findings do not support early-life cat and dog ownership in themselves increasing the risk of school-age asthma, but suggest that ownership may potentially exacerbate the risks associated with cat- and dog-specific allergic sensitisation.

Atopic Manifestations in Children Born Preterm: A Long-Term Observational Study

(1) Background: Preterm birth exposes the infant to the known risk factors for atopic diseases. We aimed to study the neonatal risk factors and to describe the clinical manifestations of atopy, including the march of symptoms, in a cohort of preschool children born preterm. (2) Methods: We enrolled neonates with gestational age < 32 weeks or birth weight < 1500 g. We classified patients in cases and controls according to the presence of at least one atopic manifestation. (3) Results: We observed 72 cases and 93 controls. Multivariate models showed that the administration of more than one cycle of antibiotics (B 0.902, p = 0.026) and gestational diabetes (B 1.207, p = 0.035) influence the risk of atopy in babies born preterm. In addition, risk of atopic dermatitis was influenced by gestational age < 29 weeks (B -1.710, p = 0.025) and gestational diabetes (B 1.275, p = 0.027). The risk of wheeze was associated with familiarity for asthma (B 1.392, p = 0.022) and the administration of more than one cycle of antibiotics (B 0.969, p = 0.025). We observed a significant reduction in the rate of atopic manifestation after 2 years of life (33.9% vs. 23.8%, p < 0.05). (4) Conclusions: Modifiable (gestational diabetes, antibiotics use) and unmodifiable (familiarity for asthma) conditions influence the risk of atopy in babies born preterm. Extreme prematurity reduces the risk of atopic dermatitis. Preterm babies showed a peculiar atopic march.

Airway microbial communities, smoking and asthma in a general population sample

BACKGROUND

Normal airway microbial communities play a central role in respiratory health but are poorly characterized. Cigarette smoking is the dominant global environmental influence on lung function, and asthma has become the most prevalent chronic respiratory disease worldwide. Both conditions have major microbial components that are incompletely defined.

METHODS

We investigated airway bacterial communities in a general population sample of 529 Australian adults. Posterior oropharyngeal swabs were analyzed by sequencing of the 16S rRNA gene. The microbiota were characterized according to their prevalence, abundance and network memberships.

FINDINGS

The microbiota were similar across the general population, and were strongly organized into co-abundance networks. Smoking was associated with diversity loss, negative effects on abundant taxa, profound alterations to network structure and expansion of Streptococcus spp. By contrast, the asthmatic microbiota were selectively affected by an increase in Neisseria spp. and by reduced numbers of low abundance but prevalent organisms.

INTERPRETATION

Our study shows that the healthy airway microbiota in this population were contained within a highly structured ecosystem, suggesting balanced relationships between the microbiome and human host factors. The marked abnormalities in smokers may contribute to chronic obstructive pulmonary disease (COPD) and lung cancer. The narrow spectrum of abnormalities in asthmatics encourages investigation of damaging and protective effects of specific bacteria.

FUNDING

The study was funded by the Asmarley Trust and a Wellcome Joint Senior Investigator Award to WOCC and MFM (WT096964MA and WT097117MA). The Busselton Healthy Ageing Study is supported by the Government of Western Australia (Office of Science, Department of Health) the City of Busselton, and private donations.

Asthma severity as a contributing factor to cancer incidence: A cohort study

BACKGROUND

A putative link between asthma and asthma severity with the occurrence of cancer has been suggested but has not been fully investigated. The objective of this study is to assess the incidence of all types of cancer in a cohort of asthmatic patients.

METHODS AND FINDINGS

A single center cohort retrospective study was conducted to investigate the role of asthma as a potential risk factor for various cancers. Participants were followed for a period of 9 years from 01/01/2010 to 30/12/2018 and cancer incidence and its determinants were collected in asthmatic patients and controls from the same population source but without any respiratory disease. Overall, 2,027 asthma patients and 1,637 controls were followed up for an average of 9 years. The statistical analysis showed that 2% of asthma patients were diagnosed with various cancers, resulting in an incidence rate of cancer of 383.02 per 100,000 persons per year which is significantly higher than the 139.01 per 100,000 persons per year observed in matched controls (p-value < 0.001). The top four cancers reported among asthmatics were breast, colon, lung and prostate cancer. Lung cancer in asthmatics had the longest diagnosis period with a mean of 36.6 years compared to the shortest with prostate cancer with 16.5 years.

CONCLUSIONS

This study shows that asthma patients are at increased risk of different types of cancers with asthma severity and goiter as the main factors that may increase the risk of developing cancers among asthmatic patients.

Upper and Lower Respiratory Signs and Symptoms in Workers Occupationally Exposed to Flour Dust

A group of 142 bakers was studied in order to investigate the relationship between higher/lower respiratory signs/symptoms and inflammation biomarkers and occupational exposure to flour dust. A complete upper and lower respiratory tract evaluation was performed. Seven percent of bakers complained of lower respiratory symptoms, while 22% of them complained of upper respiratory symptoms. Fifty five percent of the bakers were allergic, and 37.1% showed sensitization to occupational allergens. Abnormal spirometries were found in 15% of bakers, while fractional exhaled nitric oxide (FeNO) was above the normal reference in 24.5% of them. Moreover, 23.8% of bakers were found to be hyposmic. Population mean peak nasal inspiratory flow (PNIF) was in the normal range even if almost all the workers suffered from neutrophilic rhinitis at nasal cytology with the number of nasal neutrophils increasing with the increase of the duration of exposure to flour dust (p = 0.03). PNIF and FEV1 (forced expiratory volume in the 1st second) showed a positive correlation (p = 0.03; r = 0.19). The Tiffeneau index decreased with the increase of dust (p = 0.017). A similar result was obtained once we divided our population into smokers and non-smokers (p = 0.021). Long-term exposure to bakery dusts can lead to a status of minimal nasal inflammation and allergy.

Halting the March: Primary Prevention of Atopic Dermatitis and Food Allergies

Atopic dermatitis (AD) is one of the most common inflammatory skin conditions, affecting 15% to 30% of children and 2% to 10% of adults. Population-based studies suggest that having AD is associated with subsequent development of other atopic diseases, in what is known as the "atopic march." We will provide an overview of studies that investigate primary prevention strategies for the first 2 diseases in the march, namely, AD and food allergies (FA). These strategies include emollients, breastfeeding, microbial exposures, probiotics, vitamin D and UV light, water hardness, and immunotherapy. Some studies, including randomized controlled trials on emollients and microbial supplementation, have found encouraging results; however, the evidence remains limited and contradictory. With regard to breastfeeding, microbial and lifestyle exposures, vitamin D and UV light, water hardness, and immunotherapy, the lack of randomized controlled trials makes it difficult to draw definitive conclusions. Current American Academy of Pediatrics guidelines support the idea that breastfeeding for 3 to 4 months can decrease AD incidence in children less than 2 years old. Recommendations regarding a direct relationship between breastfeeding on FA, however, cannot be made because of insufficient data. Regarding microbial supplementation, most guidelines do not recommend probiotics or prebiotics for the purpose of preventing allergic diseases because of limited evidence. Before definitive conclusions can be made regarding these interventions, more well-designed, longitudinal, and randomized controlled trials, particularly in at-risk populations, are required.

Can atopy have a protective effect against cancer?

BACKGROUND

An increased prevalence of allergies and an increased incidence of breast cancer have been observed. The hypothesis that atopy may have a protective effect against the risk of different types of breast cancer was evaluated.

METHODS

In this study, 11,101 patients (11,101 women with a mean age of 55.2±14.7 years) with different types of breast cancer were tested for allergies. Allergies were confirmed based on the retrospective analysis of allergy diagnostic procedures in patients who had been previously diagnosed with breast cancer. The retrospective prevalence rates of active allergic diseases, including allergic rhinitis, bronchial asthma and atopic dermatitis, were assessed. All patients were also analyzed for bronchial asthma and allergic rhinitis according to the relevant guidelines. A group of healthy control patients was used for the comparisons.

RESULTS

The women with breast cancer had a significantly lower incidence of IgE-mediated allergic diseases than the controls. The odds ratios (ORs) for allergic rhinitis, atopic dermatitis, and bronchial asthma were 0.61 (95% CI: 0.57-0.73), 0.17 (95% CI: 0.11-0.44), and 0.73 (95% CI: 0.65-0.83), respectively. The mean serum concentrations of total IgE were significantly lower in the study population of women with breast cancer than in the patients of the control group (39.2 ± 26.2 kU/L vs. 108.5 ± 38.5 kU/L; p = 0.002).

CONCLUSION

Our results suggest that the overall incidence of allergies, especially allergic rhinitis, is lower in patients with certain types of cancer than in individuals who did not have cancer. Further studies are needed to confirm our findings.

Important Role of Immunological Responses to Environmental Exposure in the Development of Allergic Asthma

Allergic asthma is a public health problem that affects human health and socioeconomic development. Studies have found that the prevalence of asthma has significantly increased in recent years, which has become particularly pronounced in developed countries. With rapid urbanization in China in the last 3 decades, the prevalence of asthma has increased significantly in urban areas. As changes in genetic backgrounds of human populations are limited, environmental exposure may be a major factor that is responsible for the increased prevalence of asthma. This review focuses on environmental components of farms and rural areas that may have protective effects in reducing the development of asthma. Farm and rural related microorganism- and pathogen-associated molecular patterns are considered to be important environmental factors that modulate host's innate and adaptive immune system to induce protection effects later in life. Environmental microbial-related immunotherapy will also be discussed as the future research direction for the prevention of allergic asthma.

Environmental factors associated with allergy in urban and rural children from the South African Food Allergy (SAFFA) cohort

BACKGROUND

The prevalence of allergic diseases differs in urban and rural populations.

OBJECTIVE

We sought to assess associations between environmental and dietary factors with allergic diseases in urban and rural South African children.

METHODS

Toddlers aged 12 to 36 months were assessed for food allergen and aeroallergen sensitization, atopic dermatitis, allergic rhinitis, asthma, and challenge-proved food allergy. Information was collected on family history of allergic diseases, household size, socioeconomic status, delivery mode, antibiotic and probiotic use, exposure to fermented and unpasteurized milk, antihelminth treatment, sunlight exposure, pet and farm animal exposure, cigarette smoke, and household cooking and heating fuels. Antenatal exposures to pets, livestock, and cigarette smoke were assessed. A subsection completed questions on consumption of fruits and vegetables, fast foods, soft drinks/fruit juices, and fried/microwaved meat.

RESULTS

Risk and protective factors differed between urban and rural settings. Exposure to farm animals in infants and their mothers during pregnancy was protective against allergic outcomes in the rural population. Consumption of unpasteurized milk is uncommon in this group of rural children and is unlikely to be an important factor in rural protection. In urban children birth by cesarean section is associated with food allergy, and consumption of fermented milk products is associated with reduced asthma and atopic dermatitis. In both cohorts antenatal maternal smoking and environmental smoking exposure were predominantly associated with asthma, and consumption of fast foods and fried meats were associated with allergy.

CONCLUSION

In this rural environment exposure to livestock is the strongest protective factor. In urban communities, where animal contact is rare, risk factors include cesarian section, and protective factors include consumption of fermented milk products. Modifiable risk factors urgently require interventions to prevent increasing allergy rates in countries undergoing rapid urbanization.

Associations among air pollutants, grass pollens, and daily number of grass pollen allergen-positive patients: a longitudinal study from 2012 to 2016

BACKGROUND

Grass pollen is the most prevalent sensitizing aeroallergen to cause respiratory allergies in northern China. Air pollutants have a substantial effect on respiratory health and some pollens. This study aimed to investigate relationships among airborne grass pollen, air pollutants and allergic diseases, in order to determine their effects on patients with grass pollen allergies in Beijing, China, during the period from 2013 to 2016.

METHODS

Data regarding autumnal grass pollens and air pollutants measured in Beijing from 2012 to 2016 were obtained from local governmental agencies. Patient data regarding specific immunoglobulin E (IgE) analyses from 2013 to 2016 were obtained from the Department of Allergy in Beijing Tongren Hospital. Spearman's rank correlation analysis was used to assess associations between the daily number of grass pollen allergen-positive patients and the following parameters: 3 clinically-relevant grass pollen genera (Artemisia, Humulus, and Chenopodium) and inhalable pollutants.

RESULTS

Correlation analysis indicated that the daily number of grass pollen-positive patients was significantly associated with the peak period of grass pollens, as well as pollutants SO₂ and NOx. Moreover, concentrations of air pollutants (eg, ozone, oxides of nitrogen [NO_x ], and SO₂ ) were consistently and significantly associated with concentrations of grass pollens; particulate matter 2.5 µm in diameter was negatively associated with Artemisia and Chenopodium pollens.

CONCLUSION

Grass pollens exhibited substantial impact on allergic disease morbidity. Air pollutants impacted allergic disease and grass pollen. Thus, public health and clinical approaches to anticipate and reduce allergic disease morbidity from pollen and pollutants are needed.

Soil-transmitted helminth parasites and allergy: Observations from Ecuador

There is considerable interest as to potential protective effects of soil-transmitted helminths (STH) against allergy and allergic diseases. Here, we discuss findings of studies done of the effects of STH parasites on atopy and allergic diseases in Ecuador. While cross-sectional studies have consistently shown a reduced prevalence of allergen skin prick test (SPT) reactivity among infected schoolchildren, the removal of these infections by repeated deworming did not affect SPT prevalence over the short-term (ie, 12 months) but may have increased SPT prevalence over the long-term (ie, 15-17 years). In the case of allergic symptoms, cross-sectional studies have generally not shown associations with STH and intervention studies showed no impact on prevalence. However, a birth cohort suggested that early STH infections might reduce wheeze by 5 years. Allergic sensitization to Ascaris, however, explained a significant proportion of wheezing among rural schoolchildren. Studies of the effects of STH on immune and inflammatory responses indicated a potential role of STH in contributing to more robust regulation. The effects of STH on allergy are likely to be determined by history of exposure over the life-course and by interactions with a wide variety of other infectious and non-infectious factors.

Will every child have allergic rhinitis soon?

OBJECTIVES

Given the increasing prevalence of AR amongst children, we aimed to review the literature regarding the future of AR in this population.

METHODS

We searched the PubMed, Google and Proquest Central databases at Kırıkkale University Library. Search terms used were: "allergic rhinitis", "children", "paediatric", "allergy", "future", "risk factors", "treatment", "pharmacotherapy" and/or "allergen - specific immunotherapy". With regard to risk factors for allergic rhinitis, the terms "Environmental factors", "Improved hygiene", "Increased indoor allergen exposure", "Farms, villages, worms, and other parasites", "Environmental toxicants", "Diet", "Lifestyle changes", "Air pollution" and "Climate factors" were searched for. "Prevention of allergic diseases" and "Allergen-specific immunotherapy in the future" were also included in the search.

RESULTS

AR has a high prevalence and causes considerable morbidity, has associated comorbidity and features specific complications. The principal treatments rely on avoiding the allergens responsible, and administering drug treatment or immunotherapy, which targets specific antigens. Genetic drift does not explain the rising prevalence of allergic disorders, but multifactorial environmental factors are likely culprits. Amongst such environmental factors to consider are the rise in caesarean births, decreases in breast feeding, dietary changes resulting in less fresh produce being consumed, the eradication of intestinal worm infestations, alterations in the way homes are aired and heated, children taking less exercise and being outdoors for shorter periods, whilst also having more contact with pollution.

CONCLUSION

Barring substantial lifestyle alterations, more and more children are likely to develop AR. It may prove feasible to stop allergy developing in the first place through manipulation of the microbiome, but the exact format such a modification should involve remains to be discovered. Molecular allergological techniques do offer the prospect of more precisely targeted immunotherapy, the sole disease modifier at present. However, at present the complexity and cost of such interventions prevents their widespread use and research in this area is still needed. The majority of children with AR are going to be managed using nasal saline sprays, since they are the most straightforward and least risky alternative for first line treatment.

Development of atopic sensitization in Finnish and Estonian children: A latent class analysis in a multicenter cohort

BACKGROUND

The prevalence of atopy is associated with a Western lifestyle, as shown by studies comparing neighboring regions with different socioeconomic backgrounds. Atopy might reflect various conditions differing in their susceptibility to environmental factors.

OBJECTIVE

We sought to define phenotypes of atopic sensitization in early childhood and examine their association with allergic diseases and hereditary background in Finland and Estonia.

METHODS

The analysis included 1603 Finnish and 1657 Estonian children from the DIABIMMUNE multicenter young children cohort. Specific IgE levels were measured at age 3, 4, and 5 years, respectively, and categorized into 3 CAP classes. Latent class analysis was performed with the statistical software package poLCA in R software.

RESULTS

Both populations differed in terms of socioeconomic status and environmental determinants, such as pet ownership, farm-related exposure, time spent playing outdoors, and prevalence of allergic diseases (all P < .001). Nevertheless, we found similar latent classes in both populations: an unsensitized class, a food class, 2 inhalant classes differentiating between seasonal and perennial aeroallergens, and a severe atopy class. The latter was characterized by high total and specific IgE levels and strongly associated with wheeze (odds ratio [OR], 5.64 [95% CI, 3.07-10.52] and 4.56 [95% CI, 2.35-8.52]), allergic rhinitis (OR, 22.4 [95% CI, 11.67-44.54] and 13.97 [95% CI, 7.33-26.4]), and atopic eczema (OR, 9.39 [95% CI, 4.9-19.3] and 9.5 [95% CI, 5.2-17.5] for Finland and Estonia, respectively). Environmental differences were reflected in the larger seasonal inhalant atopy class in Finland, although composition of classes was comparable between countries.

CONCLUSION

Despite profound differences in environmental exposures, there might exist genuine patterns of atopic sensitization. The distribution of these patterns might determine the contribution of atopic sensitization to disease onset.

Understanding asthma phenotypes: the World Asthma Phenotypes (WASP) international collaboration

The World Asthma Phenotypes (WASP) study started in 2016 and has been conducted in five centres, in the UK, New Zealand, Brazil, Ecuador and Uganda. The objectives of this study are to combine detailed biomarker and clinical information in order to 1) better understand and characterise asthma phenotypes in high-income countries (HICs) and low and middle-income countries (LMICs), and in high and low prevalence centres; 2) compare phenotype characteristics, including clinical severity; 3) assess the risk factors for each phenotype; and 4) assess how the distribution of phenotypes differs between high prevalence and low prevalence centres. Here we present the rationale and protocol for the WASP study to enable other centres around the world to carry out similar analyses using a standardised protocol. Large collaborative and integrative studies like this are essential to further our understanding of asthma phenotypes. The findings of this study will help elucidate the aetiological mechanisms of asthma and might potentially identify new causes and guide the development of new treatments, thereby enabling better management and prevention of asthma in both HICs and LMICs.

[Allergy - an environmental disease]

The increase in allergies is a phenomenon that is being observed in all fast-developing countries. For a long time, science has taken as a starting point that solely a genetic predisposition is a precondition for the development of an allergy. Today, knowledge of environmental factors that can alter genes or the transcription of genes in the cells, has improved. Epidemiological studies have meanwhile identified several environmental factors that have a protective or supporting effect on allergy development. The environmental microbiome has recently gained central interest. A common theme in most of the studies is diversity: reduced diversity is correlated with enhanced risk for chronic inflammatory diseases and allergy.It is now of great interest for research to further analyze such environment-gene and/or environment-human interactions on all levels - from organs to cells to small and microstructures such as genes. For immunologists, it is specifically about understanding the influencing factors and effector pathways of allergens, and to apply thereby obtained insights in the follow-up for the ultimate goal of allergy research - prevention.

Is the "farm effect" hypothesis still current? Atopy and allergic diseases in rural and urban children in Poland

OBJECTIVE

The prevalence of allergic diseases has reached epidemic proportions in the Western world. Although farm-living has been associated with a lower prevalence of asthma and atopy, a marked increase in atopy among rural populations after accession to the European Union has been recently reported in Poland. Here, we aimed to investigate the effect of living environment on the prevalence of atopy and allergic diseases in Polish children.

METHODS

400 schoolchildren aged 10-14 years from the capital city (223) and from traditional rural part of the country (177) were recruited from June to November 2011. Data on allergic diseases and symptoms were collected by means of questionnaire and physical examination. Atopy was assessed based on skin prick tests (SPTs) reactivity to inhalant allergens in 350 children.

RESULTS

A high discrepancy between the prevalence of allergic symptoms (46.7%) and doctor-diagnosed allergic diseases (25%) was demonstrated (p < 0.0001). Urban children had a higher overall prevalence of allergic diseases and atopy than children living in rural areas, 29.3% versus 17.1% (p = 0.007) and 33.5% versus 20% (p = 0.0045), respectively. However, no significant differences in the rates of particular allergic diseases were noted (p > 0.05). There was higher SPT positivity to trees, grass, corn, weeds, animal dander, and molds in urban children (p < 0.05).

CONCLUSIONS

Our data support the protective effect of farm-living on the prevalence of atopy and overall allergic diseases, albeit not on particular allergic diseases, in children in Poland. The underlying mechanisms are not identified, but current socioeconomic changes may be responsible.

Human Milk and Allergic Diseases: An Unsolved Puzzle

There is conflicting evidence on the protective role of breastfeeding in relation to the development of allergic sensitisation and allergic disease. Studies vary in methodology and definition of outcomes, which lead to considerable heterogeneity. Human milk composition varies both within and between individuals, which may partially explain conflicting data. It is known that human milk composition is very complex and contains variable levels of immune active molecules, oligosaccharides, metabolites, vitamins and other nutrients and microbial content. Existing evidence suggests that modulation of human breast milk composition has potential for preventing allergic diseases in early life. In this review, we discuss associations between breastfeeding/human milk composition and allergy development.

Effect of Relocation to the U.S. on Asthma Risk Among Hispanics

INTRODUCTION

Asthma prevalence is reportedly higher among U.S.-born relative to foreign-born Hispanics/Latinos. Little is known about rates of asthma onset before and after relocation to the U.S. in Latinos. Asthma rates were examined by U.S. residence and country/territory of origin.

METHODS

In 2015-2016, age at first onset of asthma symptoms was analyzed, defined retrospectively from a cross-sectional survey in 2008-2011, in relation to birthplace and U.S. residence among 15,573 U.S.-dwelling participants (aged 18-76 years) in the Hispanic Community Health Study/Study of Latinos.

RESULTS

Cumulative incidence of asthma through age 30 years ranged from 7.9% among Mexican background individuals to 29.4% among those of Puerto Rican background. Among those born outside the U.S. mainland, the adjusted hazard for asthma was 1.52-fold higher (95% CI=1.25, 1.85) after relocation versus before relocation to the U.S. mainland, with heterogeneity in this association by Hispanic/Latino background (p-interaction<0.0001). Among foreign-born Dominicans and Mexicans, rates of asthma were greater after relocation versus before relocation (adjusted hazard ratio [AHR] for after versus before relocation, 2.42, 95% CI=1.44, 4.05 among Dominicans; AHR=2.90, 95% CI=2.02, 4.16 among Mexicans). Puerto Ricans had modestly increased asthma onset associated with U.S. mainland residence (AHR=1.52, 95% CI=1.06, 2.17). No similar increase associated with U.S. residence was observed among Central/South American immigrants (AHR=0.94, 95% CI=0.53, 1.67). Asthma rates among Cuban immigrants were lower after relocation (AHR=0.45, 95% CI=0.24, 0.82).

CONCLUSIONS

The effect of relocation to the U.S. on asthma risk among Hispanics is not uniform across Hispanic/Latino groups.

Esculetin Attenuates Th2 and Th17 Responses in an Ovalbumin-Induced Asthmatic Mouse Model

The purpose of the current study was to investigate the anti-asthmatic effect of esculetin (ES) and explore its potential mechanism with a mouse model of allergic asthma. A total number of 50 mice were randomly assigned to five groups: control, model, dexamethasone (Dex, 2 mg/kg), and ES (20 mg/kg, 40 mg/kg). Mouse asthma model was developed with the sensitization and challenge of ovalbumin (OVA). The levels of IgE in serum, eosinophilia infiltration, Th2/Th17 cytokines, Th17 cell frequency, histological condition, and the protein expressions of RORγt, GATA3 were detected. Our study demonstrated that ES inhibited, OVA-induced eosinophil count, interleukin-4 (IL-4), IL-5, IL-13, and IL-17A levels were recovered in bronchoalveolar lavage fluid. Flow cytometry (FCM) studies revealed that ES substantially inhibited Th17 cells' percentage. Western blot study also indicated that ES downregulated RORγt and GATA3 expressions. Meanwhile, ES had beneficial effects on the histological alteration. These findings suggested that ES might effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.

Exposure to Indoor Allergens in Different Residential Settings and Its Influence on IgE Sensitization in a Geographically Confined Austrian Cohort

BACKGROUND

Exposure to indoor allergens is crucial for IgE sensitization and development of allergic symptoms. Residential settings influence the allergen amount in house dust and hence allergic sensitization. Within this study, we investigated allergen exposure and molecule-based IgE levels in a geographically confined region and evaluated the impact of housing, pets and cleaning.

METHODS

501 adolescents from Salzburg, Austria participated in this cross-sectional study. House dust samples were examined regarding major mite, cat, dog, and mold allergens using a multiplex assay. Serum samples of participants were analyzed for specific IgE to Der p 1, Der p 2, Fel d 1, Can f 1 and Alt a 1 using the multiplex array ImmunoCAP ISAC. Information on allergies, living areas, dwelling form (house, flat, farm), pets, and household cleanliness were obtained by a questionnaire.

RESULTS

In investigated house dust samples, the concentration of cat allergen was highest while the prevalence of mold allergens was very low. Participants showed IgE sensitization to Der p 1 (13.2%), Der p 2 (18.2%), Fel d 1 (14.4%), Can f 1 (2.4%) and Alt a 1 (2.0%). In alpine regions, lower mite allergen concentrations were detected which correlated with reduced IgE levels. A trend for increased sensitization prevalence from rural to alpine to urban regions was noted. Living on farms resulted in lower sensitization prevalence to mite and cat allergens, even though exposure to mites was significantly elevated. The presence of cats was associated with a lower sensitization rate and IgE levels to cat and mite allergens, and less frequent allergic diseases. Cleaning did not impact allergen concentrations, while IgE reactivity to mites and allergic diseases were more pronounced when living in cleaner homes.

CONCLUSION

Allergen exposure to indoor allergens was influenced by setting of homes. Living in a farm environment and having a cat at home showed a protective effect for IgE sensitization and allergies. This cross-sectional study in combination with hereditary and lifestyle factors enables development of risk schemes for a more efficient management and potential prevention of allergic diseases.

Farm Exposure and Atopy in Men and Women: The Saskatchewan Rural Health Study

Associations between farming exposures and atopy can vary by timing of exposure and sex. We examined associations between adult atopy, sex, and farm living in a rural Canadian population. In 2010, we conducted a baseline survey of 11,982 households located in four agricultural regions of Saskatchewan, Canada. Of the 7225 adults aged 18-75, 1658 underwent clinical assessments including skin testing. Of these, 1599 participants underwent skin prick testing to four common allergens. We defined atopy as >3 mm reaction to any of four allergens compared with saline control. Farming exposures were farm living in the first year of life and current farm living. All analyses were stratified by sex. The prevalence of atopy was 17.8% and was higher in men than women (P < .001). The most common allergy was to grasses (8.8%) followed by house dust mite (HDM) mixed (8.1%). Atopy was lower in those subjects with an early farm exposure (P = .08) and who were female (P = .03). After adjusting for education, age, and smoking status, both current and early farm exposures were associated with decreased sensitization to cat atopy in women that was stronger with current exposure (P < .05). Men had significantly decreased atopic sensitization to Alternaria with an early farm exposure and increased atopic sensitization to HDM with a current farm exposure. In this rural population, the protective effect of an early farm exposure for any atopy was weak overall. The impact of farming exposures on atopy was allergen dependent and varied by sex.

Analysis of morphological and molecular composition changes in allergenic Artemisia vulgaris L. pollen under traffic pollution using SEM and FTIR spectroscopy

Nowadays, pollen allergy becomes an increasing problem for human population. Common mugwort (Artemisia vulgaris L.) is one of the major allergenic plants in Europe. In this study, the influence of air pollution caused by traffic on the structure and chemical composition of common mugwort pollen was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and curve-fitting analysis of amide I profile was applied to assess the morphological and structural changes of mugwort pollen grains collected from sites with different vehicle pollution levels. Microscopic observations support the conclusion, that the higher the car traffic, the smaller the pollen grains. The obtained results clearly show that air pollution had an impact on different maximum absorbance values of individual functional groups composing the chemical structure of pollen. Moreover, air pollution induced structural changes in macromolecules of mugwort pollen. In pollen collected from the unpolluted site, the content of sporopollenin (850 cm^-1) was the highest, whereas polysaccharide concentration (1032 cm^-1) was the lowest. Significant differences were observed in lipids. Pollen collected from the site with heavy traffic had the lowest content of lipids at 1709, 2071, and 2930 cm^-1. The largest differences were observed in the spectra regions corresponding to proteins. In pollen collected from unpolluted site, the highest level of β-sheet (1600 cm^-1) and α-helix (1650 cm^-1) was detected. The structural changes in proteins, observed in the second derivative of the FTIR spectrum and in the curve-fitting analysis of amide I profile, could be caused inter alia by air pollutants. Alterations in protein structure and in their content in the pollen may increase the sensitization and subsequent risk of allergy in predisposed people. The obtained results suggest that the changes in chemical composition of pollen may be a good indicator of air quality and that FTIR may be successfully applied in biomonitoring.

Changes in the prevalence of cigarette smoking and quitting smoking determinants in adult inhabitants of rural areas in Poland between 2003 and 2012

OBJECTIVES

We investigate trends in the prevalence of cigarette smoking among adults at all ages in two time points 9 years apart in two neighbouring rural populations and examine social and respiratory health determinants of quitting smoking.

STUDY DESIGN

Repeated cross-sectional study.

METHODS

Two cross-sectional surveys were conducted in the same rural area of lower Silesia in Poland in 2003 and 2012. A total of 1328 (91% of adult eligible individuals) in 2003 and 1449 (92% of eligible) in 2012 adult inhabitants were surveyed, 908 people (560 villagers and 348 town inhabitants) participated in both surveys. Participants completed a questionnaire on smoking behaviour, education level and respiratory diseases.

RESULTS

Current smoking was higher in the villages than the town, among men than women and those with a middle level of education. The prevalence of current smokers decreased over time, although this decline was much more pronounced in the town than in the villages (30.2% vs 23% and 35.5% vs 33.7%, respectively). Men were more likely to stop smoking than women both in villages and in town. The prevalence of current smokers among village women even increased between the two surveys from 27.6% to 29.3%. Respiratory diseases did not influence quitting smoking.

CONCLUSIONS

The degree of decreasing trend in smoking prevalence varied considerably within neighbouring populations. It was mainly seen in the town and among younger people. Men and those better educated were more willing to quit smoking. The discrepancies between two close rural populations indicates the need for an individual approach when designing programs of tobacco control.

Association between cancer and allergies

Background

The prevalence of allergies and the incidence of cancer are both increasing worldwide. It has been hypothesized that atopy may affect the risk of some cancers.

Methods

In this study, 1525 patients (754 women and 771 men with a mean age of 52.7 ± 11.9 years) with different types of cancer were examined for the presence of allergies. Allergies were confirmed based on retrospective analysis of allergy diagnostic procedures in patients previously diagnosed with cancer. All patients were also analyzed for bronchial asthma and allergic rhinitis according to relevant guidelines. A control group of patients without cancer diagnoses was used for comparison.

Results

Patients with cancer had significantly fewer IgE-mediated allergic diseases than the control population. For the oncological group compared to the non-cancer patients, the odds ratios (ORs) for allergic rhinitis, atopic dermatitis, and bronchial asthma were 0.67 (95 % CI 0.52–0.81), 0.89 (95 % CI 0.78–0.99), and 1.03 (95 % CI 0.91–1.13), respectively. The mean serum concentrations of total IgE were significantly lower in the study population of patients with cancer than in the patients in the control group (45.98 ± 14.9 vs. 83.2 ± 40.1 IU/l; p < 0.05). There were no significant correlations between the type of cancer diagnosed and the form of allergy.

Conclusion

Our results indicate that the overall incidence of allergies, particularly allergic rhinitis, was lower in patients with some types of cancer. Further studies are needed to confirm our findings.

The genes and the environment in nasal allergy

PURPOSE OF REVIEW

In this review, we summarize the latest publications on the genetic and environmental determinants of allergic rhinitis.

RECENT FINDINGS

Recent advances in genetic technology and bioinformatics have enabled simultaneous unbiased analysis of the entire genome regarding DNA sequence variants, epigenetic modifications and gene expression, providing functional correlates for DNA variants and phenotypes. As a result, new genes of mitochondrial and B-lymphocyte metabolism have been associated with allergic rhinitis phenotypes. Epidemiological studies recently showed an increased risk to develop allergic rhinitis in all age groups with reduction in farm exposure and in children with few older siblings. Climate changes seem to have also influenced pollen exposure and pollen-induced allergic disease. Lastly, occupational rhinitis has been increasingly recognized as a large burden to society.

SUMMARY

In summary, new high throughput genetics research technologies have pointed to new previously unsuspected pathways that may modulate the risk of developing allergic rhinitis such as mitochondrial metabolism. In addition, recent environmental factors found to influence the risk of developing allergic rhinitis include exposure to farm, pollution, occupational agents, and changes in climate.

The microbial environment and its influence on asthma prevention in early life

There is accumulating evidence to suggest that the environmental microbiome plays a significant role in asthma development. The very low prevalence of asthma in populations highly exposed to microbial environments (farm children and Amish populations) highlights its preventive potential. This microbial diversity might be necessary to instruct a well-adapted immune response and regulated inflammatory responses to other inhaled and ingested environmental elements, such as allergens, particles, and viruses. Like the internal gut microbiome, which is increasingly recognized as an important instructor of immune maturation, the external environmental microbiome might shape immune responses on the skin, airway mucosal surfaces, and potentially also the gut early in life. The diversity of the external microbial world will ensure that of the many maladapted pathways leading to asthma development, most, if not all, will be counterbalanced. Likewise, important contributors to asthma, such as allergen sensitization and allergic manifestations early in life, are being suppressed. Thus the facets of innate immunity targeted by microbes and their compounds and metabolites might be the master switch to asthma and allergy protection, which has been found in environments rich in microbial exposures.

Early farm residency and prevalence of asthma and hay fever in adults

BACKGROUND

Asthma and hay fever have been found to be both positively and negatively associated with farming lifestyles in adulthood. Lack of congruency may depend upon early life exposure.

OBJECTIVE

To assess the importance of different periods of farm residency for asthma and hay fever in an adult Canadian population.

METHODS

We conducted a questionnaire survey in rural Saskatchewan, Canada. We assessed a history of asthma and hay fever with five categories of farm residency that were mutually exclusive: first year of life only, currently living on a farm, both first year of life and currently living on a farm, other farm living, and no farm living. Generalized estimating equations were used to adjust for clustering effects of adults within households.

RESULTS

Of the 7148 responding, 30.6% had an early farm living experience only, 34.4% had both early and current farm living experiences, while 17.4% had never lived on a farm. The overall prevalence of ever asthma and hay fever was 8.6% and 12.3%, respectively, and was higher in women. Sex modified the associations between ever asthma and hay fever with farm residency variables whereby women had a decreased risk for both asthma [adjusted odds ratio (ORadj): 0.67, 95% confidence interval (CI):0.47-0.96] and hay fever (ORadj: 0.60, 95% CI: 0.44-0.83) with an early farm exposure only. Men currently living on a farm without an early farm exposure had an increased risk for ever asthma (ORadj: 1.82, 95% CI: 1.02-3.24).

CONCLUSION

Farm residency in the first year of life shows a protective effect for adult asthma and hay fever that appears to differ by sex.

Changes in atopy prevalence and sibship effect in rural population at all ages

BACKGROUND

We examined the associations of family size and birth order with atopy prevalence in rural Poland at two time periods.

METHODS

Two cross-sectional surveys were conducted in the same villages and a small town of lower Silesia at an interval of 9 years. In 2003, 1700 (88% of eligible individuals), and in 2012, 1730 (86%) inhabitants aged 5 years or more completed a questionnaire and had a skin prick test for atopy.

RESULTS

There was an inverse association between family size and atopy in the village population in 2003; the prevalence of atopy was the highest for those with no siblings (15.2%) and decreased to 5.4% for those with three and more siblings (OR = 0.22; 0.07-0.66). In contrast, there was little or no such protective effect in the town population where the prevalence of atopy was much higher (7.3% in the villages, 20.0% in the town). Nine years later, the prevalence of atopy had increased in the village to be similar to that in the town (19.6% and 19.9% respectively), and the protective effects of family size and birth order in the villages were much weaker (OR = 0.64; 95% CI 0.33-1.27 for three or more siblings). Both protective effects were strongest among children.

CONCLUSIONS

The protective effects of family size and birth order on atopy were much stronger in children than in adults and among those living in a village. They largely disappeared with the steep increase in atopy prevalence at all ages; this followed environmental changes on the village farms.

Increasing prevalence of asthma, respiratory symptoms, and allergic diseases: Four repeated surveys from 1993-2014

BACKGROUND

Published data shows different prevalence trends depending on the region of Europe.

AIM

The aim of the study was to analyze time trends of the frequency of the respiratory symptoms and allergic diseases in school children (Silesia, Poland) over the last 21 years.

METHODS

We compared the results of four population-based surveys performed in a town of Chorzow in 1993, 2002, 2007 and 2014 in children aged 7-10 years. All four studies had the same study protocol, recruitment (cluster, school-based sampling), questionnaire (WHO respiratory health questionnaire) and the same principal investigator The surveys included 1130 children in 1993, 1421 children in 2002, 1661 children in 2007 and 1698 in 2014.

RESULTS

The results covered a 21 year span and showed a statistically significant (p < 0.05) increase in the prevalence of the following physician-diagnosed disorders (1993-2002-2007-2014): asthma (3.4%-4.8%-8.6%-12,6%); allergic rhinitis (4.3%-11.9%-15.9%-13.9%); atopic dermatitis (3.6%-7.9%-12.0%-13.9%); allergic conjunctivitis (4.3%-7.9%-8.3%-7.9%); A simultaneous increasing trend (p < 0.05) in the attacks of dyspnea (3.9%-5.9%-7.0%-7.3%) and symptoms (wheeze, dyspnea, cough) induced by exercise (7.5%-10.6%-22.0%-22.4%) and - at the same time - decrease (p < 0.05) in the prevalence of cough (31.6%-19.6%15.4%-14.4%). Among children with diagnosed asthma during the 21 year span there was significantly (p < 0.05) increased proportion of treated children (51.3%-51.3%-69.5%-60.7%) and a lower frequency of presenting current symptoms.

CONCLUSIONS

Our findings are in line with the concept of a real increase in the occurrence of asthma and allergic disease in children. The pattern involves not only physician-diagnosed allergic diseases but also occurrence of symptoms related to respiratory disorders. Diagnosed asthma is better treated and better controlled.