Maternal exposure to smoking and wheezing phenotypes in children: a cohort study of the Japan Environment and Children's Study.

BACKGROUND: Previous studies have shown that prenatal maternal smoking and maternal secondhand smoke exposure during pregnancy were associated with an increased risk of wheezing and asthma development. However, few studies have examined the influence of different sources of tobacco exposure in different perinatal timeframes (preconception, prenatal, and postnatal) on wheezing phenotypes in children. Using national survey data from Japan, we investigated the effects of exposure to tobacco smoke during pregnancy on wheezing phenotypes in children before the age of 3 years. METHODS: Pregnant women who lived in the 15 regional centers in the Japan Environment and Children's Study were recruited. We obtained information on prenatal and postnatal exposure to active and secondhand smoke (SHS) and wheeze development up to 3 years of age. Multiple logistic regression analysis was performed to determine the association between tobacco smoke exposure and wheezing phenotypes in children. RESULTS: We analyzed 73,057 singleton births and identified four longitudinal wheezing phenotypes: never wheezing; early transient wheezing (wheezing by age 1 year but not thereafter); late-onset wheezing (wheezing by age 2-3 years but not beforehand); and persistent wheezing. Maternal smoking during pregnancy was significantly associated with early transient and persistent wheezing in children compared with no maternal smoking [early transient wheezing: 1-10 cigarettes per day, adjusted odds ratio (aOR) 1.43, 95% confidence interval (CI) 1.23-1.66; ≥ 11 cigarettes per day, aOR 1.67, 95% CI 1.27-2.20; persistent wheezing: 1-10 cigarettes per day, aOR 1.64, 95% CI 1.37-1.97; ≥ 11 cigarettes per day, aOR 2.32, 95% CI 1.70-3.19]. Smoking cessation even before pregnancy was also significantly associated with increased risk of early transient wheezing, late-onset wheezing, and persistent wheezing in children. Moreover, maternal exposure to SHS during pregnancy was significantly associated with increased risk of early transient and persistent wheezing compared with no such exposure. CONCLUSIONS: Maternal smoking before and throughout pregnancy was associated with wheeze development in children up to 3 years of age. It appears that smoking is detrimental compared to never smoking, regardless of whether individuals quit smoking before or after becoming aware of the pregnancy.

Recurrent wheezing and asthma-Epidemiology and environmental determinants.

Wheeze is the musical continuous sound produced by oscillations in any critically narrowed airways, and heard mostly on expiration. It is common in preschool age, about half of all children will experience an episode of wheezing by their sixth birthday. Asthma is usually characterized by cough, wheeze, chest tightness and fast breathing. It is a significant global health issue and affects both children and adults. The prevalence is on the increase, especially in LMIC. Studies from different populations have revealed the key role influencing the progression from preschool wheezing to childhood asthma. Recurrent wheezing is four or more episodes in the preceding year and has a spectrum of phenotypes and with heterogeneous features. Phenotypes of wheezing were proposed to facilitate the identification of young children who are at risk of subsequent development of asthma. The epidemiology and environmental determinants of recurrent wheezing and asthma are discussed.

Prenatal exposure to phthalates and childhood wheeze and asthma in the progress cohort.

INTRODUCTION: Prenatal phthalate exposure may influence lung development and lead to wheezing and asthma in childhood, and these associations may vary by sex. Despite ubiquity of exposure, there is limited epidemiologic data on these associations in Latin America. METHODS: We assessed 593 mother-child dyads enrolled in the Programming Research in Obesity, Growth, Environment, and Social Stressors birth cohort in Mexico City. We quantified 15 phthalate metabolites in 2nd and 3rd trimester maternal urine. Report of ever wheeze, wheeze in the past 12 months (current wheeze) and ever asthma were obtained using a validated survey when children were 4 and 6 years of age. We examined individual associations with modified Poisson models. Mixture effects were assessed using Bayesian Weighted Quantile Sum (BWQS) regression. All models were adjusted for child's sex, maternal age and education at enrollment, and parity. RESULTS: In Poisson models, a doubling of mono (carboxy-isononyl) phthalate (MCNP) during the 2nd trimester was associated with higher risk of wheeze (RR: 1.14, 95 % CI: 1.01, 1.29), and asthma (RR: 1.44, 95 % CI: 1.05, 1.97) at 4 years of age. Higher concentrations of the sum of di-isononyl phthalate metabolites (∑DiNP) during the 2nd trimester were also associated with asthma at 4 years of age (RR: 1.30, 95 % CI: 1.04, 1.61). Mixture associations of phthalate metabolite concentrations during the 2nd trimester and asthma at 4 years of age were stronger in males (BWQS, OR: 1.94, 95 % CI: 0.90, 4.60; 90 % CrI: 1.04, 3.73) compared to females (BWQS, OR: 1.23, 95 % CI: 0.56, 2.88; 90 % CrI: 0.61, 2.55). Additionally, we observed stronger inverse associations between prenatal phthalate mixtures during the 3rd trimester and current wheeze at 4 and 6 years of age in females (BWQS, OR: 0.54, 90 % CrI: 0.35, 0.82; OR: 0.45, 90 % CrI: 0.22, 0.84) compared to males (BWQS, OR: 0.95, 90 % Cri: 0.68, 1.35; OR: 0.97, 90 % CrI: 0.59, 1.54). CONCLUSIONS: Prenatal phthalate metabolite concentrations were associated with respiratory outcomes in childhood, with some evidence of sex specific effects. Future work investigating phthalate exposure and wheeze trajectories/lung function will be important for understanding how these may predict later disease.

Risk Factors for Nonattendance Among Children With Asthma: A Systematic Review and Meta-Analysis.

BACKGROUND: Nonattendance at scheduled outpatient visits among children with asthma has been associated with an increased risk of acute asthma events and increased health care expenses. Specific risk factors for nonattendance have been suggested, but a comprehensive overview is lacking. OBJECTIVE: To investigate risk factors for nonattendance among children with asthma and assess whether nonattendance associates with acute events through a systematic review and meta-analysis. METHODS: The study (PROSPERO: CRD42023471893) was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines using the PubMed, Ovid MEDLINE, Embase, ClinicalTrials.gov, and Cochrane Library databases and search terms "asthma/wheeze," "child," and "nonattendance." Original peer-reviewed studies in English were included and evaluated for risk of bias using the Newcastle Ottawa scale. A meta-analysis was performed for all risk factors. Finally, we analyzed whether nonattendance was associated with the risk of acute events. RESULTS: A total of 17 studies encompassing 27,023 children with asthma were included. The meta-analysis was performed on 11 eligible studies, with 25,948 children, and identified the following risk factors for nonattendance; teenage versus preteen (odds ratio [OR] 1.26; 95% confidence interval [95% CI] 1.06-1.49; P < .01), non-White versus White ethnicity (OR 1.51; 95% CI 1.04-2.18; P = .03) and lower disease severity (OR 1.41; 95% CI 1.13-1.77; P < .01). There were no significant findings in the meta-analysis for insurance status, atopy, sex, or rural residence. Nonattendance associated with an increased risk of acute asthma events (OR 1.11; 95% CI 1.07-1.16; P < .01). CONCLUSIONS: This systematic review and meta-analysis identified specific risk factors to facilitate the development of a strategy against nonattendance for pediatric patients with asthma. This is particularly important given nonattendance being associated with an increased risk of acute asthma.

Chorioamnionitis and respiratory outcomes in prematurely born children: a systematic review and meta analysis.

INTRODUCTION: To conduct a systematic review and meta-analysis of the association between chorioamnionitis and respiratory outcomes of prematurely born children. CONTENT: Pubmed, Medline and Embase were searched for relevant studies. Studies were included if they assessed prematurely born children, who had been exposed to chorioamnionitis and had either lung function testing or assessment of wheeze or asthma following NICU discharge. Two reviewers independently screened the search results, applied inclusion criteria and assessed methodological quality. One reviewer extracted the data and these were checked by a second reviewer. SUMMARY: A total of 1,237 studies were identified, but only eight which included 35,000 infants, fulfilled the inclusion criteria. One study looked at both lung function results and wheeze or asthma in childhood. Four of five studies found an association between wheeze/asthma in childhood and exposure to chorioamnionitis: the overall Odds Ratio (OR) for developing wheeze/asthma in childhood was OR 1.71 (95 % CI: 1.55-1.89). Four studies looked at lung function in childhood, three of which showed no statistically significant association between chorioamnionitis exposure and altered lung function. One study found lower lung function in those exposed to chorioamnionitis and lower expiratory flows with increasing levels of chorioamnionitis (forced expiratory flow at 50 % of exhaled forced vital capacity (=FEF50) p=0.012, forced expiratory flow at 25-75 % of the forced vital capacity is exhaled (=FEF25-75) p=0.014). OUTLOOK: There was a significant association between chorioamnionitis and the development of wheeze or asthma in childhood, but overall not in impairment of lung function.

Deep multiomic profiling reveals molecular signatures that underpin preschool wheeze and asthma.

BACKGROUND: Wheezing in childhood is prevalent, with over one-half of all children experiencing at least 1 episode by age 6. The pathophysiology of wheeze, especially why some children develop asthma while others do not, remains unclear. OBJECTIVES: This study addresses the knowledge gap by investigating the transition from preschool wheeze to asthma using multiomic profiling. METHODS: Unsupervised, group-agnostic integrative multiomic factor analysis was performed using host/bacterial (meta)transcriptomic and bacterial shotgun metagenomic datasets from bronchial brush samples paired with metabolomic/lipidomic data from bronchoalveolar lavage samples acquired from children 1-17 years old. RESULTS: Two multiomic factors were identified: one characterizing preschool-aged recurrent wheeze and another capturing an inferred trajectory from health to wheeze and school-aged asthma. Recurrent wheeze was driven by type 1-immune signatures, coupled with upregulation of immune-related and neutrophil-associated lipids and metabolites. Comparatively, progression toward asthma from ages 1 to 18 was dominated by changes related to airway epithelial cell gene expression, type 2-immune responses, and constituents of the airway microbiome, such as increased Haemophilus influenzae. CONCLUSIONS: These factors highlighted distinctions between an inflammation-related phenotype in preschool wheeze, and the predominance of airway epithelial-related changes linked with the inferred trajectory toward asthma. These findings provide insights into the differential mechanisms driving the progression from wheeze to asthma and may inform targeted therapeutic strategies.

Impact of wheat sensitization on wheeze and T2 phenotypes in general population of children.

Background: The association between sensitization to specific aeroallergens and outcomes in patients with asthma is well researched; however, the association between childhood-onset wheeze/asthma and sensitization to various aeroallergens and food allergens in the general pediatric population remains poorly understood. Objective: We sought to investigate the association between sensitization to common aeroallergens and food allergens with wheeze and type 2 (T2) inflammation in the general pediatric population. Methods: Specific IgEs against 9 aeroallergens and 4 food allergens were measured in the prospective Hokkaido birth cohort of 428 school-age children (age ∼10 years). Wheeze and other allergic symptoms were assessed using the International Study of Asthma and Allergies in Childhood questionnaire. Blood eosinophil count and fractional exhaled nitric oxide level were assessed as T2 biomarkers. The Isle of Wight birth cohort in the United Kingdom was used for replication analysis (n = 1032). Results: The prevalence of sensitization to at least 1 aeroallergen and food allergen was 70.5% and 22.3%, respectively. A significant association between wheeze and sensitization to aeroallergens such as ragweed, Japanese cedar, mugwort, and pet dander was found. However, the association between wheeze and wheat sensitization was highly significant (Hokkaido birth cohort: odds ratio, 4.67; 95% CI, 1.98-11.01; Isle of Wight birth cohort, odds ratio, 4.01; 95% CI, 1.78-9.07). Sensitization to most aeroallergens, though not any food allergen, was associated with the T2-high phenotype. Conclusions: Sensitization to wheat may be an important risk factor for wheeze/asthma development, especially the pathogenesis of T2-non/low asthma, independent of aeroallergens, in the general pediatric population.

Prevalence of Alpha-1 Antitrypsin Deficiency Alleles in a Lithuanian Cohort of Wheezing Small Children.

Severe inherited alpha-1 antitrypsin deficiency (AATD) is an autosomal genetic condition linked to chronic obstructive pulmonary disease (COPD). The significance of heterozygous, milder deficiency variants (PiSZ, PiMZ, PiMS) is less clear. We studied AATD genotypes in 145 children (up to 72 months old) with assessed wheezing severity using the Pediatric Respiratory Assessment Measure (BCCH PRAM score). A control group of 74 children without airway obstruction was included. AAT concentration and Pi phenotype were determined from dry blood spot samples using nephelometry and real-time PCR; PiS and PiZ alleles were identified by isoelectrofocusing. Among the wheezers, the Pi*S allele incidence was 2.07% (3 cases) and the Pi*Z allele was 6.9% (10 cases). The Pi*Z allele frequency was higher in wheezers compared to controls (44.8% vs. 20.27%) and the general Lithuanian population (44.8% vs. 13.6%) and was similar to adult COPD patients in Lithuania: Pi*S 10.3% vs. 15.8% and Pi*Z 44.8% vs. 46.1%. No association was found between AAT genotypes and wheezing severity. Finding that wheezer children exhibit a frequency of Z* and S* alleles like that found in adults with COPD suggests a potential genetic predisposition that links early wheezing in children to the development of COPD in adulthood. Larger cohort studies are needed to confirm this finding.

Maternal asthma during pregnancy and risks of allergy and asthma in progeny: A systematic review and meta-analysis.

BACKGROUND: Clinical and preclinical evidence indicate that in utero maternal asthma exposure increases progeny asthma risk. Whether maternal asthma also increases the risks of progeny allergy is unclear. OBJECTIVES: To synthesise the available evidence on the relationship between in utero exposure to maternal asthma and postnatal asthma, wheezing and allergic diseases (Prospero: CRD42020201538). SEARCH STRATEGY: We systematically searched MEDLINE [PubMed], Embase [Ovid], Web of Science, Informit Health, the Cochrane Library, CINAHL [EBSCOhost], MedNar [Deep Web Technologies], ProQuest Theses and Dissertations, Scopus [Elsevier] and Trove, to the end of 2023. SELECTION CRITERIA: Studies reporting asthma, wheeze and/or allergic disease in progeny of women with and without asthma or with asthma classified by control, exacerbation or severity. DATA COLLECTION AND ANALYSIS: Double screening, selection, data extraction and quality assessment were performed, using Joanna Briggs Institute (JBI) scoring. MAIN RESULTS: Of 134 non-overlapping studies, 127 were included in ≥1 meta-analysis. Maternal asthma ever was associated with greater risks of asthma (65 studies, risk ratio [95% confidence interval] 1.76 [1.57-1.96]), wheeze (35 studies, 1.59 [1.52-1.66]), food allergy (5 studies, 1.32 [1.23-1.40]), allergic rhinitis (7 studies, 1.18 [1.06-1.31]) and allergic dermatitis (14 studies, 1.17 [1.11-1.23]) ever in progeny. Asthma during the pregnancy, more severe, and uncontrolled maternal asthma were each associated with greater risks of progeny asthma. CONCLUSIONS: Children of mothers with asthma are at increased risk for the development of allergic diseases. Whether improved maternal asthma control reduces risks of child allergy as well as asthma requires further investigation.

Current Practices in Pediatric Asthma Care.

This article is a comprehensive review of the latest knowledge and developments on pediatric asthma. It serves as a guide for general practitioners and subspecialists who treat asthma. The pathophysiology and critical features of asthma that should be addressed and the latest therapies available are discussed. The areas where further investigation is needed are also highlighted.

Assessing the Impact of Non-Exhaust Emissions on the Asthmatic Airway (IONA) Protocol for a Randomised Three-Exposure Crossover Study.

BACKGROUND: People living with asthma are disproportionately affected by air pollution, with increased symptoms, medication usage, hospital admissions, and the risk of death. To date, there has been a focus on exhaust emissions, but traffic-related air pollution (TRAP) can also arise from the mechanical abrasion of tyres, brakes, and road surfaces. We therefore created a study with the aim of investigating the acute impacts of non-exhaust emissions (NEEs) on the lung function and airway immune status of asthmatic adults. METHODS: A randomised three-condition crossover panel design will expose adults with asthma using a 2.5 h intermittent cycling protocol in a random order at three locations in London, selected to provide the greatest contrast in the NEE components within TRAP. Lung function will be monitored using oscillometry, fractional exhaled nitric oxide, and spirometry (the primary outcome is the forced expiratory volume in one second). Biomarkers of inflammation and airborne metal exposure will be measured in the upper airway using nasal lavage. Symptom responses will be monitored using questionnaires. Sources of exhaust and non-exhaust concentrations will be established using source apportionment via the positive matrix factorisation of high-time resolution chemical measures conducted at the exposure sites. DISCUSSION: Collectively, this study will provide us with valuable information on the health effects of NEE components within ambient PM2.5 and PM10, whilst establishing a biological mechanism to help contextualise current epidemiological observations.

Current technological advancement in asthma care.

INTRODUCTION: Asthma is a common chronic respiratory disease affecting 262 million people globally, causing half a million deaths each year. Poor asthma outcomes are frequently due to non-adherence to medication, poor engagement with asthma services, and a lack of objective diagnostic tests. In recent years, technologies have been developed to improve diagnosis, monitoring, and care. AREAS COVERED: Technology has impacted asthma care with the potential to improve patient outcomes, reduce healthcare costs, and provide personalized management. We focus on current evidence on home diagnostics and monitoring, remote asthma reviews, and digital smart inhalers. PubMed, Ovid/Embase, Cochrane Library, Scopus and Google Scholar were searched in November 2023 with no limit by year of publication. EXPERT OPINION: Advanced diagnostic technologies have enabled early asthma detection and personalized treatment plans. Mobile applications and digital therapeutics empower patients to manage their condition and improve adherence to treatments. Telemedicine platforms and remote monitoring devices have the potential to streamline asthma care. AI algorithms can analyze patient data and predict exacerbations in proof-of-concept studies. Technology can potentially provide precision medicine to a wider patient group in the future, but further development is essential for implementation into routine care which in itself will be a major challenge.

Viral and non-viral episodes of wheezing in early life and the development of asthma and respiratory phenotypes among urban children.

BACKGROUND: Viral wheezing is an important risk factor for asthma, which comprises several respiratory phenotypes. We sought to understand if the etiology of early-life wheezing illnesses relates to childhood respiratory and asthma phenotypes. METHODS: Data were collected prospectively on 429 children in the Urban Environment and Childhood Asthma (URECA) birth cohort study through age 10 years. We identified wheezing illnesses and the corresponding viral etiology (PCR testing of nasal mucus) during the first 3 years of life. Six phenotypes of respiratory health were identified at 10 years of age based on trajectories of wheezing, allergic sensitization, and lung function. We compared the etiology of early wheezing illnesses to these wheezing respiratory phenotypes and the development of asthma. RESULTS: In the first 3 years of life, at least one virus was detected in 324 (67%) of the 483 wheezing episodes documented in the study cohort. Using hierarchical partitioning we found that non-viral wheezing episodes accounted for the greatest variance in asthma diagnosed at both 7 and 10 years of age (8.0% and 5.8% respectively). Rhinovirus wheezing illnesses explained the most variance in respiratory phenotype outcome followed by non-viral wheezing episodes (4.9% and 3.9% respectively) at 10 years of age. CONCLUSION AND RELEVANCE: Within this high-risk urban-residing cohort in early life, non-viral wheezing episodes were frequently identified and associated with asthma development. Though rhinovirus wheezing illnesses had the greatest association with phenotype outcome, the specific etiology of wheezing episodes in early life provided limited information about subsequent wheezing phenotypes.

Potential asthma risk factors do not account for global asthma symptom prevalence patterns and time trends in children and adolescents.

Background: The International Study of Asthma and Allergies in Childhood (ISAAC) and the Global Asthma Network (GAN) conducted a series of global asthma prevalence surveys, between 1990 and 2020, in adolescents aged 13-14 and children aged 6-7 years. We used them to assess whether potential asthma risk factors explain global asthma symptom prevalence trends over this period. Method: We fitted mixed-effects linear regression models to estimate associations between centre-level risk factor prevalence and both the mid-point asthma symptom prevalence and the change per decade. We also estimated the 2019 asthma symptom prevalence across all included centres. Results: For adolescents, across 50 centres in 26 countries there was weak evidence that decreasing asthma prevalence over time was associated with regular fast-food consumption and frequent television viewing. However, frequent television viewing, along with heavy truck traffic, were associated with higher prevalence of asthma symptoms at the study mid-point. For children, across 41 centres in 21 countries, no risk factors were associated with time trends in asthma symptom prevalence, but truck traffic and paracetamol in the first year of life were associated with higher mid-point prevalence.We estimated the 2019 asthma symptom prevalence, across a total of 124 centres, to be 12.8% (11.4%, 14.2%) with little evidence of a difference by age. Low-income countries had lower prevalence (children 5.2% [2.5%, 7.8%], adolescents 5.3% [2.8%, 7.8%]), than lower-middle-, upper-middle- and high-income countries (all approximately 14-15%). Including risk factors in the models did not change the estimates. Conclusion: Potential asthma risk factors do not seem to explain the global prevalence patterns or time trends. Country income accounts for some of the differences, but the unexplained variation is very high.

Respiratory conditions and health symptoms associated with air pollution amongst children aged six years and below in Melusi Informal Settlement, Tshwane Metropolitan Municipality, South Africa: a cross-sectional study.

BACKGROUND: Respiratory conditions and health symptoms associated with air pollution in children are a major public health concern, as their immune systems and lungs are not yet fully developed. This study aimed to assess self-reported respiratory conditions and health symptoms associated with air pollution sources amongst children aged six years and below in Melusi informal settlement, Tshwane Metropolitan Municipality, South Africa. METHODS: With a quantitative cross-sectional study design, parents/caregivers of children aged six years and below (n = 300) from eight Early Childhood Development Centres were invited to participate in the study. This study employed complete sampling, and data was collected using the modified International Study of Asthma and Allergies in Children. The chi-square and multiple logistic regression models were used to analyze data, with p < 0.05 in the adjusted odds ratios considered as being statistically significant. RESULTS: Three models were run to examine the predictors of wheezing in the past 12 months, dry cough, and itchy-watery eyes. The model for asthma was excluded, as only seven participants reported having asthma. Wheeze in the past 12 months was associated with participants living in the area for more than three years (OR 2.96 95%CI: 1.011-8.674). Furthermore, having a dog in the house in the past 12 months was associated with wheeze in the past 12 months (OR 5.98 95%CI: 2.107-16.967). There was an association between duration of stay in a residence and dry cough prevalence (OR 5.63 95%CI: 2.175-14.584). Trucks always or frequently passing near homes was associated with itchy-watery eyes (OR 3.27 95%CI: 1.358-7.889). 59% (59%) of participants perceived the indoor air quality in their homes to be good, while 6% perceived it as poor. In contrast, 36% of participants perceived the outdoor air quality to be good, and 19.7% perceived it as poor. CONCLUSION: The association between perceived air pollution exposure, self-reported respiratory conditions, and health symptoms amongst children is complex. Further research is required to better understand the multifaceted nature of air pollution and its impact on the health of children.

Use of Antibiotics in Infancy and Asthma in Childhood: Confounded or Causal Relationship? A Critical Review of the Literature.

Childhood asthma is among the most common chronic lung diseases in the pediatric population, having substantial consequences on the everyday life of children and their caregivers. There remains a lack of a singular, efficacious strategy for averting the inception of childhood asthma. The rate of pediatric antibiotic usage continues to be high, which makes it crucial to understand whether there exists a causal link between the use of antibiotics in infancy and the development of asthma in childhood. In this rostrum, we conduct a critical review of the literature concerning the association of infant antibiotic use and the onset of childhood asthma. Drawing on the results of 5 meta-analyses addressing this topic and of a recent randomized controlled trial, a notable association emerges between antibiotic exposure in the first year of life and the occurrence of childhood asthma that appears to be beyond potential study limitations (such as reverse causation, confounding by indication, and recall bias). Furthermore, we highlight the need for additional research in this field that could improve our understanding of important aspects of this association and lead to the design of an intervention aimed to deliver antibiotics safely during early life and reduce the burden of childhood asthma.

Disease Severity and Cytokine Expression in the Rhinovirus-Induced First Wheezing Episode.

Wheezing children infected with rhinovirus (RV) have a markedly increased risk of subsequently developing recurrencies and asthma. No previous studies have assessed the association between cytokine response and the severity of acute illness in the first wheezing episode in children infected with RV. Forty-seven children treated both as inpatients and as outpatients infected with RV only, aged 3-23 months, with severe first wheezing episodes were recruited. During acute illness, peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with anti-CD3/anti-CD28 in vitro. A multiplex ELISA was used to quantitatively identify 56 different cytokines. The mean age of the children was 17 months, 74% were males, 79% were hospitalized, and 33% were sensitized. In adjusted analyses, the inpatient group was characterized by decreased expressions of interferon gamma (IFN-γ), interleukin 10 (IL-10), macrophage inflammatory protein 1 alpha (MIP-1α), RANTES (CCL5), and tumor necrosis factor-alpha (TNF-α) and an increased expression of ENA-78 (CXCL5) compared to the outpatient group. The cytokine response profiles from the PBMCs were different between the inpatient and outpatient groups. Our results support that firmly controlled interplay between pro-inflammatory and anti-inflammatory responses are required during acute viral infection to absolve the initial infection leading, to less severe illness.

Preventing progression of preschool wheezing to asthma: Opportunities for intervention.

Recurrent wheezing in preschool children is heterogeneous and results from numerous genetic and environmental risk factors, which result in the same final clinical manifestation of acute episodes of wheezing but have distinct underlying mechanisms. Effective disease-modifying approaches, therefore, need to target the pathways driving the symptoms. We have good evidence to show that targeting airway eosinophilia alone in early-life preschool wheezing and using inhaled corticosteroids is not disease-modifying. Although airway remodelling develops early in preschool wheezing, the challenge is identifying suitable treatments for structural airway changes. There is increasing evidence for the role of lower airway bacterial infection contributing to wheeze episodes, but clinical trials investigating the impact of targeted antibiotic treatment on disease modification are needed. There is also increasing data supporting an association between lower airway neutrophilia and wheezing in a subgroup of preschool children, but direct causation and the role of neutrophil function remain unknown. Finally, there is encouraging preliminary data for the role of inactivated mixed bacterial lysates in children with non-allergic, infection-associated wheeze episodes, but the impact on longer-term outcomes and their mechanism of action is unknown. This review outlines a range of potential novel targets and approaches that may enable secondary prevention of asthma from preschool wheezing. In parallel, the potential for harm when interventions are introduced indiscriminately is highlighted. Some of the challenges that need to be addressed, including trial designs allowing tailored interventions, the need for non-invasive biomarkers for targeted interventions, and ensuring extended and long-term follow-up after intervention, are highlighted.

Association of pesticide exposure with respiratory health outcomes and rhinitis in avocado farmworkers from Michoacán, Mexico.

BACKGROUND: A growing literature suggests associations between occupational pesticide exposure and respiratory health. In this study, we aimed to examine the association of exposure to insecticides, fungicides, and herbicides, individually and as a mixture, with respiratory health outcomes and rhinitis in avocado farmworkers from Michoacán, Mexico. MATERIAL AND METHODS: We conducted a cross-sectional study of 105 avocado farmworkers between May and August 2021. We quantified 12 insecticide, fungicide, and herbicide metabolites in urine samples collected during two study visits (8-10 weeks apart). We collected survey data on self-reported pesticide use during the 12 months prior to the baseline survey and estimated annual exposure-intensity scores (EIS) using a semi-quantitative exposure algorithm. We also assessed respiratory symptoms, including wheezing, chest tightness, wheezing after exercise, and night cough. We used generalized linear regression models to examine associations of individual urinary metabolite concentrations and annual EIS with respiratory health outcomes and rhinitis. Mixture effects were assessed using Bayesian Weighted Quantile Sum (BWQS) regression. RESULTS: After adjusting for multiple comparisons, we observed mostly null associations of individual pesticide metabolite concentrations and annual EIS with the outcomes of interest. However, in BWQS analyses, we found evidence of a mixture association of urinary pesticide metabolites with increased odds of night cough (OR: 5.34, 95 % CrI: 1.67, 20.62). Pyrethroid metabolites 3-phenoxybenzoic acid and cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid were the main contributors to this association (43 %). CONCLUSIONS: Our findings indicate that exposure to a mixture of pesticides, particularly pyrethroid insecticides, may be associated with night cough in avocado farmworkers.