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The Human Epidemiology and Response to SARS-CoV-2 (HEROS) Study is a prospective, multicity, 6-month incidence study conducted from May 2020 to February 2021. The objectives were to identify risk factors for SARS-CoV-2 infection and household transmission among children and people with asthma and allergic diseases, and to use the host nasal transcriptome sampled longitudinally to understand infection risk and sequelae at the molecular level. To overcome challenges of clinical study implementation due to the coronavirus pandemic, this surveillance study used direct-to-participant methods to remotely enroll and prospectively follow eligible children who are participants in other National Institutes of Health–funded pediatric research studies and their household members. Households participated in weekly surveys and biweekly nasal sampling regardless of symptoms. The aim of this report is to widely share the methods and study instruments and to describe the rationale, design, execution, logistics, and characteristics of a large, observational, household-based, remote cohort study of SARS-CoV-2 infection and transmission in households with children. The study enrolled a total of 5598 individuals, including 1913 principal participants (children), 1913 primary caregivers, 729 secondary caregivers, and 1043 other household children. This study was successfully implemented without necessitating any in-person research visits and provides an approach for rapid execution of clinical research. Trial registration: ClinicalTrials.gov. Identifier: NCT04375761 [ABSTRACT FROM AUTHOR]

Rationale: Allergic inflammation has been linked to increased susceptibility to viral illnesses, but it is unclear whether this association is causal.Objectives: To test whether omalizumab treatment to reduce IgE would shorten the frequency and duration of rhinovirus (RV) illnesses in children with allergic asthma.Methods: In the PROSE (Preventative Omalizumab or Step-up Therapy for Severe Fall Exacerbations) study, we examined children with allergic asthma (aged 6-17 yr; n = 478) from low-income census tracts in eight U.S. cities, and we analyzed virology for the groups randomized to treatment with guidelines-based asthma care (n = 89) or add-on omalizumab (n = 259). Weekly nasal mucus samples were analyzed for RVs, and respiratory symptoms and asthma exacerbations were recorded over a 90-day period during the fall seasons of 2012 or 2013. Adjusted illness rates (illnesses per sample) by treatment arm were calculated using Poisson regression.Measurements and Main Results: RVs were detected in 97 (57%) of 171 exacerbation samples and 2,150 (36%) of 5,959 nonexacerbation samples (OR, 2.32; P < 0.001). Exacerbations were significantly associated with detection of rhinovirus C (OR, 2.85; P < 0.001) and rhinovirus A (OR, 2.92; P < 0.001), as well as, to a lesser extent, rhinovirus B (OR, 1.98; P = 0.019). Omalizumab decreased the duration of RV infection (11.2 d vs. 12.4 d; P = 0.03) and reduced peak RV shedding by 0.4 log units (95% confidence interval, -0.77 to -0.02; P = 0.04). Finally, omalizumab decreased the frequency of RV illnesses (risk ratio, 0.64; 95% confidence interval, 0.49-0.84).Conclusions: In children with allergic asthma, treatment with omalizumab decreased the duration of RV infections, viral shedding, and the risk of RV illnesses. These findings provide direct evidence that blocking IgE decreases susceptibility to RV infections and illness. Clinical trial registered with www.clinicaltrials.gov (NCT01430403). [ABSTRACT FROM AUTHOR]

Background: Decreased 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with an increased prevalence and severity of asthma and a lower response to inhaled corticosteroids. Objective: The objective was to determine the association between serum 25(OH)D concentrations and asthma prevalence, severity, and response to asthma treatment. Design: Secondary analyses were conducted in 2 samples of adolescents 12-20 y of age: 1) NHANES 2001-2006 (n = 6487), a cross-sectional nationally representative sample of the US population, and 2) a cohort of inner-city adolescents with asthma managed prospectively for 46 wk with guidelines-based therapy in the Asthma Control Evaluation (ACE; n = 226) trial. Results: Mean (±SD) serum 25(OH)D concentrations in the NHANES and ACE samples were lower in African Americans than in non-African Americans (NHANES: 14.9 ± 6.5 compared with 23.0 ± 8.4 ng/mL, P < 0.0001; ACE: 11.2 ± 6.9 compared with 15.8 ± 7.1 ng/mL, P < 0.0001). In the NHANES sample, mean concentrations did not differ between participants without and with asthma (African Americans: 14.9 ± 6.4 compared with 15.0 ± 6.6 ng/mL, respectively, P = 0.87; non-African Americans: 23.0 ± 8.5 compared with 23.6 ± 8.2 ng/mL, respectively, P = 0.16). In the ACE models that used either a predefined cutoff (<20 ng/mL) or linear regression, 25(OH)D concentrations showed either no relation or minor contradictory correlations with indicators of asthma severity, treatment requirements, spirometry, or atopy/inflammation. Conclusion: In 2 samples of adolescents, overall serum 25(OH)D concentrations were low and were not consistently associated with the presence of asthma, multiple asthma characteristics, asthma morbidity, or response to treatment. The ACE trial was registered at clinicaltrials.gov as NCT0011441. [ABSTRACT FROM AUTHOR]

Background: Asthma severity is reflected in many aspects of the disease, including impairment and future risks, particularly for exacerbations. According to the Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma, however, to assess more comprehensively the severity of asthma the level of current treatment needed to maintain a level of control should be included. Objective: Development and validation of a new instrument, the Composite Asthma Severity Index (CASI), which can quantify disease severity by taking into account impairment, risk, and the amount of medication needed to maintain control. At present, there is no instrument available to measure and assess the multidimensional nature of asthma. Methods: Twenty-six established asthma investigators, who are part of the National Institutes of Health–supported Inner City Asthma Consortium, participated in a modified Delphi consensus process to identify and weight the dimensions of asthma. Factor analysis was performed to identify independent domains of asthma by using the Asthma Control Evaluation trial. CASI was validated by using the Inner City Anti-IgE Therapy for Asthma trial. Results: CASI scores include 5 domains: day symptoms and albuterol use, night symptoms and albuterol use, controller treatment, lung function measures, and exacerbations. At Asthma Control Evaluation trial enrollment, CASI ranged from 0 to 17, with a mean of 6.2. CASI was stable, with minimal change in variance after 1 year of treatment. In external validation, CASI detected a 32% larger improvement than did symptoms alone. Conclusion: CASI retained its discriminatory ability even with low levels of symptoms reported after months of guidelines-directed care. Thus, CASI has the ability to determine the level of asthma severity and provide a composite clinical characterization of asthma. [ABSTRACT FROM AUTHOR]

Background: The National Health and Nutrition Examination Survey (NHANES) 2005-2006 was the first population-based study to investigate levels of serum total and allergen-specific IgE in the general US population. Objective: We estimated the prevalence of allergy-related outcomes and examined relationships between serum IgE levels and these outcomes in a representative sample of the US population. Methods: Data for this cross-sectional analysis were obtained from NHANES 2005-2006. Study subjects aged 6 years and older (n = 8086) had blood taken for measurement of total IgE and 19 specific IgE levels against common aeroallergens, including Alternaria alternata, Aspergillus fumigatus, Bermuda grass, birch, oak, ragweed, Russian thistle, rye grass, cat dander, cockroach, dog dander, dust mite (Dermatophagoides farinae and Dermatophagoides pteronyssinus), mouse and rat urine proteins, and selected foods (egg white, cow’s milk, peanut, and shrimp). Serum samples were analyzed for total and allergen-specific IgE by using the Pharmacia CAP System. Information on allergy-related outcomes and demographics was collected by questionnaire. Results: In NHANES 2005-2006, 6.6% reported current hay fever, and 23.5% had current allergies. Allergy-related outcomes increased with increasing total IgE levels (adjusted odds ratios for a 10-fold increase in total IgE level of 1.86 [95% CI, 1.44-2.41] for hay fever and 1.64 [95% CI, 1.41-1.91] for allergies). Increased levels of plant-, pet-, and mold-specific IgE contributed independently to allergy-related symptoms. The greatest increase in odds was observed for hay fever and plant-specific IgE (adjusted odds ratio, 4.75; 95% CI, 3.83-5.88). Conclusion: In the US population self-reported allergy symptoms are most consistently associated with increased levels of plant-, pet-, and mold-specific IgE. [ABSTRACT FROM AUTHOR]

Background: Cholesterol exerts complex effects on inflammation. There has been little investigation of whether serum cholesterol is associated with asthma, an inflammatory airways disease with great public health impact. Objective: To determine relationships between levels of 3 serum cholesterol measures (total cholesterol [TC], high-density lipoprotein cholesterol [HDL-C], and non–HDL-C) and asthma/wheeze in a sample representative of the US population. Methods: Cross-sectional study of 7005 participants age ≥6 years from the 2005 to 2006 National Health and Nutrition Examination Survey. Results: Serum TC and non–HDL-C were lower in patients with current asthma than in subjects without current asthma in the overall population (TC, 188.5 vs 192.2 mg/dL; non–HDL-C, 133.9 vs 137.7 mg/dL; P < .05 for both), whereas HDL-C was not different. Adjusted odds ratios (ORs) from multivariate logistic regression per 1-SD increase of TC and non–HDL-C for current asthma were 0.92 (95% CI, 0.86-0.98) and 0.91 (95% CI, 0.85-0.98), respectively. On racial/ethnic stratification, these relationships reflect marked reductions unique to Mexican Americans (MAs; TC, 171.4 vs 189.3 mg/dL; P < .001; OR, 0.62; 95% CI, 0.48-0.80; non–HDL-C, 119.8 vs 137.9 mg/dL; P < .001; OR, 0.62; 95% CI, 0.48-0.79). Among MAs, the adjusted OR for wheeze requiring medical attention was 0.57 (95% CI, 0.43-0.75) for TC and 0.53 (95% CI, 0.33-0.85) for non–HDL-C. Relationships between cholesterol and asthma/wheeze were independent of body mass index and serum C-reactive protein, and similar between atopic and nonatopic participants. Conclusion: Serum TC and non–HDL-C are inversely related to asthma in the US population, chiefly reflecting a relationship among MAs. [Copyright &y& Elsevier]

Background: The prevalence of both obesity and allergic disease has increased among children over the last several decades. Previous literature on the relationship between obesity and allergic disease has been inconsistent. It is not known whether systemic inflammation could be a factor in this relationship. Objective: We sought to examine the association of obesity with total and allergen-specific IgE levels and allergy symptoms in US children and adolescents and to assess the role of C-reactive protein. Methods: National Health and Nutrition Examination Survey data from 2005-2006 included measurement of total and allergen-specific IgE levels and allergy questions. Overweight was defined as the 85th or greater to less than the 95th percentile of body mass index for age, and obesity was defined as the 95th percentile or greater. Linear and logistic regression models were used to examine the association of weight categories with total IgE levels, atopy, allergen-specific IgE levels, and allergy symptoms among youth aged 2 to 19 years. Results: Geometric mean total IgE levels were higher among obese (geometric mean ratio, 1.31; 95% CI, 1.10-1.57) and overweight (ratio, 1.25; 95% CI, 1.02-1.54) children than among normal-weight children. The odds ratio (OR) for atopy (any positive specific IgE measurement) was increased in the obese children compared with that seen in those of normal weight; this association was driven largely by allergic sensitization to foods (OR for atopy, 1.26 [95% CI, 1.03-1.55]; OR for food sensitization, 1.59 [95% CI, 1.28-1.98]). C-reactive protein levels were associated with total IgE levels, atopy, and food sensitization. Conclusions: Obesity might be a contributor to the increased prevalence of allergic disease in children, particularly food allergy. Systemic inflammation might play a role in the development of allergic disease. [Copyright &y& Elsevier]

Background: Black and Hispanic children living in urban environments in the USA have an excess burden of morbidity and mortality from asthma. Therapies directed at the eosinophilic phenotype reduce asthma exacerbations in adults, but few data are available in children and diverse populations. Furthermore, the molecular mechanisms that underlie exacerbations either being prevented by, or persisting despite, immune-based therapies are not well understood. We aimed to determine whether mepolizumab, added to guidelines-based care, reduced the number of asthma exacerbations during a 52-week period compared with guidelines-based care alone.Methods: This is a randomised, double-blind, placebo-controlled, parallel-group trial done at nine urban medical centres in the USA. Children and adolescents aged 6-17 years, who lived in socioeconomically disadvantaged neighbourhoods and had exacerbation-prone asthma (defined as ≥two exacerbations in the previous year) and blood eosinophils of at least 150 cells per μL were randomly assigned 1:1 to mepolizumab (6-11 years: 40 mg; 12-17 years: 100 mg) or placebo injections once every 4 weeks, plus guideline-based care, for 52 weeks. Randomisation was done using a validated automated system. Participants, investigators, and the research staff who collected outcome measures remained masked to group assignments. The primary outcome was the number of asthma exacerbations that were treated with systemic corticosteroids during 52 weeks in the intention-to-treat population. The mechanisms of treatment response were assessed by study investigators using nasal transcriptomic modular analysis. Safety was assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03292588.Findings: Between Nov 1, 2017, and Mar 12, 2020, we recruited 585 children and adolescents. We screened 390 individuals, of whom 335 met the inclusion criteria and were enrolled. 290 met the randomisation criteria, were randomly assigned to mepolizumab (n=146) or placebo (n=144), and were included in the intention-to-treat analysis. 248 completed the study. The mean number of asthma exacerbations within the 52-week study period was 0·96 (95% CI 0·78-1·17) with mepolizumab and 1·30 (1·08-1·57) with placebo (rate ratio 0·73; 0·56-0·96; p=0·027). Treatment-emergent adverse events occurred in 42 (29%) of 146 participants in the mepolizumab group versus 16 (11%) of 144 participants in the placebo group. No deaths were attributed to mepolizumab.Interpretation: Phenotype-directed therapy with mepolizumab in urban children with exacerbation-prone eosinophilic asthma reduced the number of exacerbations.Funding: US National Institute of Allergy and Infectious Diseases and GlaxoSmithKline. [ABSTRACT FROM AUTHOR]

Abstract: Background: Consistent performance of allergen assays is essential to ensure reproducibility of exposure assessments for investigations of asthma and occupational allergic disease. This study evaluated intra- and inter-laboratory reproducibility of a fluorescent multiplex array, which simultaneously measures eight indoor allergens in a single reaction well. Methods: A multi-center study was performed in nine laboratories in the US and Europe to determine the inter-laboratory variability of an 8-plex array for dust mite, cat, dog, rat, mouse and cockroach allergens. Aliquots of 151 dust extract samples were sent to participating centers and analyzed by each laboratory on three separate occasions. Agreement within and between laboratories was calculated by the concordance correlation coefficient (CCC). Results: Results were obtained for over 32,000 individual allergen measurements. Levels covered a wide range for all allergens from below the lower limit of detection (LLOD=0.1–9.8ng/ml) to higher than 6800ng/ml for all allergens except Mus m 1, which was up to 1700ng/ml. Results were reproducible within as well as between laboratories. Within laboratories, 94% of CCC were ≥0.90, and 80% of intra-laboratory results fell within a 10% coefficient of variance (CV%). Results between laboratories also showed highly significant positive correlations for all allergens (~0.95, p<0.001). Overall means of results were comparable, and inter-laboratory CV% for all allergens except Rat n 1 ranged between 17.6% and 26.6%. Conclusion: The data indicate that performance criteria for fluorescent multiplex array technology are reproducible within and between laboratories. Multiplex technology provides standardized and consistent allergen measurements that will streamline environmental exposure assessments in allergic disease. [Copyright &y& Elsevier]

Background: Asthma prevalence and severity have markedly increased with urbanisation, and children in low-income urban centres have among the greatest asthma morbidity. Outdoor air pollution has been associated with adverse respiratory effects in children with asthma. However, the mechanisms by which air pollution exposure exacerbates asthma, and how these mechanisms compare with exacerbations induced by respiratory viruses, are poorly understood. We aimed to investigate the associations between regional air pollutant concentrations, respiratory illnesses, lung function, and upper airway transcriptional signatures in children with asthma, with particular focus on asthma exacerbations occurring in the absence of respiratory virus., Methods: We performed a retrospective analysis of data from the MUPPITS1 cohort and validated our findings in the ICATA cohort. The MUPPITS1 cohort recruited 208 children aged 6-17 years living in urban areas across nine US cities with exacerbation-prone asthma between Oct 7, 2015, and Oct 18, 2016, and monitored them during reported respiratory illnesses. The last MUPPITS1 study visit occurred on Jan 6, 2017. The ICATA cohort recruited 419 participants aged 6-20 years with persistent allergic asthma living in urban sites across eight US cities between Oct 23, 2006, and March 25, 2008, and the last study visit occurred on Dec 30, 2009. We included participants from the MUPPITS1 cohort who reported a respiratory illness at some point during the follow-up and participants from the ICATA cohort who had nasal samples collected during respiratory illness or at a scheduled visit. We used air quality index values and air pollutant concentrations for PM 2·5 , PM 10 , O 3 , NO 2 , SO 2 , CO, and Pb from the US Environmental Protection Agency spanning the years of both cohorts, and matched values and concentrations to each illness for each participant. We investigated the associations between regional air pollutant concentrations and respiratory illnesses and asthma exacerbations, pulmonary function, and upper airway transcriptional signatures by use of a combination of generalised additive models, case crossover analyses, and generalised linear mixed-effects models., Findings: Of the 208 participants from the MUPPITS1 cohort and 419 participants from the ICATA cohort, 168 participants in the MUPPITS1 cohort (98 male participants and 70 female participants) and 189 participants in the ICATA cohort (115 male participants and 74 female participants) were included in our analysis. We identified that increased air quality index values, driven predominantly by increased PM 2·5 and O 3 concentrations, were significantly associated with asthma exacerbations and decreases in pulmonary function that occurred in the absence of a provoking viral infection. Moreover, individual pollutants were significantly associated with altered gene expression in coordinated inflammatory pathways, including PM 2·5 with increased epithelial induction of tissue kallikreins, mucus hypersecretion, and barrier functions and O 3 with increased type-2 inflammation., Interpretation: Our findings suggest that air pollution is an important independent risk factor for asthma exacerbations in children living in urban areas and is potentially linked to exacerbations through specific inflammatory pathways in the airway. Further investigation of these potential mechanistic pathways could inform asthma prevention and management approaches., Funding: National Institutes of Health, National Institute of Allergy and Infectious Diseases., Competing Interests: Declaration of interests MCA, MK, GTO, RCM, EW, PL, AC, MAG, RSG, AHL, SL-D, JAP, CMK, GKKH, EMZ, SJT, LBB, WWB, JEG, and DJJ report grants from the US National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases, and Division of Allergy, Immunology, and Transplantation during the conduct of study. MCA reports personal fees for consulting from Regeneron, outside the submitted work. AHL reports personal fees from Phadia ThermoFisher as consulting honoraria; grants and non-financial support from ResMed–Propeller Health; non-financial support from Revenio; grants and personal fees from Avillion; and personal fees from Labcorp, all outside the submitted work. SL-D reports funding from the National Heart, Lung, and Blood Institute (NHLBI) and the Robert Wood Johnson Foundation. JAP reports provisions of study drug for other asthma studies from GlaxoSmithKline, Boehringer Ingelheim, and Genentech–Novartis. CMK reports royalties from UpToDate. SJT reports grant meetings to support the CAUSE network from NIH–NIAID, payment for episode on biologics in asthma care from Medscape, and personal fees from UpToDate, all outside the submitted work. LBB reports personal fees from GlaxoSmithKline, Genentech–Novartis, Teva, AstraZeneca, WebMD–Medscape, DBV Technologies, Sanofi–Regeneron, OM Pharma, Kinaset, Vertex, and the American Board of Allergy and Immunology; non-financial support from the American Academy of Allergy Asthma and Immunology; and royalties from Elsevier, all outside the submitted work. WWB reports personal fees from Novartis, GlaxoSmithKline, Genentech, Sanofi, AstraZeneca, Regeneron, and Elsevier, outside the submitted work. JEG reports personal fees and stock options from Meissa Vaccines, personal fees from AstraZeneca and Ena Therapeutics, and a patent on methods for production of rhinoviruses. DJJ reports personal fees from Novartis, Avillion, Pfizer, AstraZeneca, and Sanofi; grants and personal fees from GlaxoSmithKline and Regeneron; and grants from NIH–NHLBI, all outside the submitted work. LMW, SMS, PJG, and AT declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: A relationship between adiposity and asthma has been described in some cohort studies, but little is known about trajectories of adiposity throughout early childhood among children at high risk for developing asthma in urban United States cities. Moreover, early life trajectories of adipokines that have metabolic and immunologic properties have not been comprehensively investigated., Objective: Our objective was to characterize trajectories of adiposity in a longitudinal birth cohort of predominately Black and Latinx children (n = 418) using several different repeated measures including body mass index (BMI) z score, bioimpedance analysis, leptin, and adiponectin in the first 10 years of life., Methods: In a longitudinal birth cohort of predominately Black and Latinx children, we used repeated annual measures of BMI, bioimpedance analysis (ie, percentage of body fat), leptin, and adiponectin to create trajectories across the first 10 years of life. Across those trajectories, we compared asthma diagnosis and multiple lung function outcomes, including spirometry, impulse oscillometry, and methacholine response., Results: Three trajectories were observed for BMI z score, bioimpedance analysis, and leptin and 2 for adiponectin. There was no association between trajectories of BMI, percentage of body fat, leptin, or adipokine and asthma diagnosis or lung function (P > .05)., Conclusions: Trajectories of adiposity were not associated with asthma or lung function in children at high risk for developing asthma. Risk factors related to geography as well as social and demographic factors unique to specific populations could explain the lack of association and should be considered in obesity and asthma studies., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

Background: Multicenter randomized controlled trials (RCTs) for asthma management that incorporate usual-care regimens could benefit from standardized application of evidence-based guidelines., Objective: We sought to evaluate performance of a computerized decision support tool, the Asthma Control Evaluation and Treatment (ACET) Program, to standardize usual-care regimens for asthma management in RCTs., Methods: Children and adolescents with persistent uncontrolled asthma living in urban census tracts were recruited into 3 multicenter RCTs (each with a usual-care arm) between 2004 and 2014. A computerized decision support tool scored asthma control and assigned an appropriate treatment step based on published guidelines. Control-level determinants (symptoms, rescue medication use, pulmonary function measure, and adherence estimates) were collected at visits and entered into the ACET Program. Changes in control levels and treatment steps were examined during the trials., Results: At screening, more than half of the participants were rated as having symptoms that were not controlled or poorly controlled. The proportion of participants who gained good control between screening and randomization increased significantly in all 3 trials. Between 51% and 70% had symptoms that were well controlled by randomization. The proportion of well-controlled participants remained constant or improved slightly from randomization until the last posttreatment visit. Nighttime symptoms were the most common control-level determinant; there were few (<1%) instances of complete overlap of factors. FEV 1 was the driver of control-level assignment in 30% of determinations., Conclusion: The ACET Program decision support tool facilitated standardized asthma assessment and treatment in multicenter RCTs and was associated with attaining and maintaining good asthma control in most participants., (Copyright © 2018 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

Background: Children with asthma are at increased risk for experiencing health and educational disparities because of increased school absence. School nurses are well positioned to support asthma management and improve school attendance., Objective: We sought to implement and assess the effect of the Building Bridges for Asthma Care Program on improving school attendance and measures of asthma control., Methods: Children with asthma (age, 5-14 years) in the Denver Public School System (n = 240) and the Hartford Public School System (n = 223) were enrolled in the Building Bridges Program during the 2013-2014 and 2014-2015 school years and followed until the end of the second school year. The primary outcome was school absence, with secondary outcomes, including asthma control, measured based on Childhood Asthma Control Test or the Asthma Control Test scores and rescue inhaler use., Results: Participants experienced a 22% absolute decrease in school absenteeism, the number of children with an Asthma Control Test/Childhood Asthma Control Test score of less than the control threshold of 20 decreased from 42.7% to 28.8%, and bronchodilator use greater than 2 times per week decreased from 35.8% to 22.9% (all changes were significant, P < .01)., Conclusions: Children enrolled in the Building Bridges for Asthma Care Program experienced reduced school absence and improved asthma control., (Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: Although pets are found in more than 50% of US homes, the effect of pet allergen exposure on asthma morbidity in the US population is not well documented., Objective: To determine the effect of dog and cat allergen exposures on asthma morbidity in the US population., Methods: The National Health and Nutrition Examination Survey is a representative sample of civilian US population. Data on asthma, dog and cat allergen levels in bedroom dust, as well as specific IgE to dog and cat were analyzed for all participants 6 years or older., Results: Pets are common in the United States, with more that 50% of households having a dog or a cat or both. The prevalence of allergic sensitization in the National Health and Nutrition Examination Survey population was similar for dog and cat, with both being approximately 12%. Among those who were sensitized, exposure to elevated levels of pet allergens was associated with an increased prevalence of asthma and asthma attacks. Indeed, 44.2% of the asthma attacks were attributable to exposure to high levels of dog allergen in the bedroom among patients with asthma sensitive to dog and 30.3% were attributable to cat allergen exposure among the comparable cat-sensitive and exposed group. Projecting these results to the US population indicates more than 1 million increased asthma attacks each year for the dog-sensitive and exposed group and more than 500,000 increased asthma attacks for the cat-sensitive and exposed population of patients with asthma., Conclusions: Exposure to elevated levels of dog and cat allergens among those sensitized individuals with asthma is associated with excess asthma attacks. Reducing pet allergen exposures has the potential for a significant decrease in asthma morbidity., (Published by Elsevier Inc.)

Background: A Seasonal Asthma Exacerbation Predictive Index (saEPI) was previously reported based on 2 prior National Institute of Allergy and Infectious Diseases Inner City Asthma Consortium trials., Objective: This study sought to validate the saEPI in a separate trial designed to prevent fall exacerbations with omalizumab therapy., Methods: The saEPI and its components were analyzed to characterize those who had an asthma exacerbation during the Preventative Omalizumab or Step-Up Therapy for Fall Exacerbations (PROSE) study. We characterized those inner-city children with and without asthma exacerbations in the fall period treated with guidelines-based therapy (GBT) in the absence and presence of omalizumab., Results: A higher saEPI was associated with an exacerbation in both the GBT alone (P < .001; area under the curve, 0.76) and the GBT + omalizumab group (P < .01; area under the curve, 0.65). In the GBT group, younger age at recruitment, higher total IgE, higher blood eosinophil percentage and number, and higher treatment step were associated with those who had an exacerbation compared with those who did not. In the GBT + omalizumab group, younger age at recruitment, increased eosinophil number, recent exacerbation, and higher treatment step were also associated with those who had an exacerbation. The saEPI was associated with a high negative predictive value in both groups., Conclusions: An exacerbation in children treated with GBT with or without omalizumab was associated with a higher saEPI along with higher markers of allergic inflammation, treatment step, and a recent exacerbation. Those that exacerbated on omalizumab had similar features with the exception of some markers of allergic sensitization, indicating a need to develop better markers to predict poor response to omalizumab therapy and alternative treatment strategies for children with these risk factors. The saEPI was able to reliably predict those children unlikely to have an asthma exacerbation in both groups., (Copyright © 2017 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

Background: Wheezing illnesses cause major morbidity in infants and are frequent precursors to asthma., Objective: We sought to examine environmental factors associated with recurrent wheezing in inner-city environments., Methods: The Urban Environment and Childhood Asthma study examined a birth cohort at high risk for asthma (n = 560) in Baltimore, Boston, New York, and St Louis. Environmental assessments included allergen exposure and, in a nested case-control study of 104 children, the bacterial content of house dust collected in the first year of life. Associations were determined among environmental factors, aeroallergen sensitization, and recurrent wheezing at age 3 years., Results: Cumulative allergen exposure over the first 3 years was associated with allergic sensitization, and sensitization at age 3 years was related to recurrent wheeze. In contrast, first-year exposure to cockroach, mouse, and cat allergens was negatively associated with recurrent wheeze (odds ratio, 0.60, 0.65, and 0.75, respectively; P ≤ .01). Differences in house dust bacterial content in the first year, especially reduced exposure to specific Firmicutes and Bacteriodetes, was associated with atopy and atopic wheeze. Exposure to high levels of both allergens and this subset of bacteria in the first year of life was most common among children without atopy or wheeze., Conclusions: In inner-city environments children with the highest exposure to specific allergens and bacteria during their first year were least likely to have recurrent wheeze and allergic sensitization. These findings suggest that concomitant exposure to high levels of certain allergens and bacteria in early life might be beneficial and suggest new preventive strategies for wheezing and allergic diseases., (Copyright © 2014 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

Background: Allergic sensitization is an important risk factor for the development of atopic disease. The National Health and Nutrition Examination Survey (NHANES) 2005-2006 provides the most comprehensive information on IgE-mediated sensitization in the general US population., Objective: We investigated clustering, sociodemographic, and regional patterns of allergic sensitization and examined risk factors associated with IgE-mediated sensitization., Methods: Data for this cross-sectional analysis were obtained from NHANES 2005-2006. Participants aged 1 year or older (n = 9440) were tested for serum specific IgEs (sIgEs) to inhalant and food allergens; participants 6 years or older were tested for 19 sIgEs, and children aged 1 to 5 years were tested for 9 sIgEs. Serum samples were analyzed by using the ImmunoCAP System. Information on demographics and participants' characteristics was collected by means of questionnaire., Results: Of the study population aged 6 years and older, 44.6% had detectable sIgEs, whereas 36.2% of children aged 1 to 5 years were sensitized to 1 or more allergens. Allergen-specific IgEs clustered into 7 groups that might have largely reflected biological cross-reactivity. Although sensitization to individual allergens and allergen types showed regional variation, the overall prevalence of sensitization did not differ across census regions, except in early childhood. In multivariate modeling young age, male sex, non-Hispanic black race/ethnicity, geographic location (census region), and reported pet avoidance measures were most consistently associated with IgE-mediated sensitization., Conclusions: The overall prevalence of allergic sensitization does not vary across US census regions, except in early life, although allergen-specific sensitization differs based on sociodemographic and regional factors. Biological cross-reactivity might be an important but not the sole contributor to the clustering of allergen-specific IgEs., (Published by Mosby, Inc.)

Background: The inability to measure IgE-based sensitivity to all allergens has limited our understanding of what portion of asthma is related to IgE. Total IgE measurement can potentially overcome this limitation., Objective: We sought to determine the association between total IgE levels and asthma., Methods: The National Health and Nutrition Examination Survey 2005-2006 examined a representative sample of the US population 6 years of age and older., Results: The median total IgE level was 40.8 kU/L (interquartile range, 15.5-114 kU/L). Total IgE levels varied with age, sex, race/ethnicity, serum cotinine level, body size, and socioeconomic status. The prevalence of current asthma was 8.8%. The prevalence of atopy was 42.5%, as defined by 15 specific IgEs. The adjusted odds ratio (OR) for asthma with a 10-fold increase in total IgE level was 2.18 (95% CI, 1.66-2.87). Total IgE level predicted asthma only among atopic subjects (OR, 2.41; 95% CI, 1.62-3.60) and not among nonatopic subjects (OR, 1.11; 95% CI, 0.72-1.71; interaction P = .005). Among atopic subjects, the association between total IgE level and asthma became stronger as the number of positive specific IgE test results increased. Asthma was present at even the lowest levels of total IgE, regardless of atopic status. Approximately 92% of atopic subjects were identified by 6 specific IgEs, but to increase the identification to more than 99% required 11 specific IgEs., Conclusion: Total IgE levels are associated with asthma only among persons who have positive results for at least 1 allergen-specific IgE. Asthma independent of IgE is not uncommon in the US population. The complete identification of atopic subjects in a population requires a large panel of allergen-specific IgEs.