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BACKGROUND: Most genetic studies of asthma and allergy have focused on common variation in individuals primarily of European ancestry. Studying the role of rare variation in quantitative phenotypes and in asthma phenotypes in populations of diverse ancestries can provide additional, important insights into the development of these traits. OBJECTIVE: We sought to examine the contribution of rare variants to different asthma- or allergy-associated quantitative traits in children with diverse ancestries and explore their role in asthma phenotypes. METHODS: We examined whole-genome sequencing data from children participants in longitudinal studies of asthma (n = 1035; parent-identified as 67% Black and 25% Hispanic) to identify rare variants (minor allele frequency < 0.01). We assigned variants to genes and tested for associations using an omnibus variant-set test between each of 24,902 genes and 8 asthma-associated quantitative traits. On combining our results with external data on predicted gene expression in humans and mouse knockout studies, we identified 3 candidate genes. A burden of rare variants in each gene and in a combined 3-gene score was tested for its associations with clinical phenotypes of asthma. Finally, published single-cell gene expression data in lower airway mucosal cells after allergen challenge were used to assess transcriptional responses to allergen. RESULTS: Rare variants in USF1 were significantly associated with blood neutrophil count (P = 2.18 × 10-7); rare variants in TNFRSF21 with total IgE (P = 6.47 × 10-6) and PIK3R6 with eosinophil count (P = 4.10 × 10-5) reached suggestive significance. These 3 findings were supported by independent data from human and mouse studies. A burden of rare variants in TNFRSF21 and in a 3-gene score was associated with allergy-related phenotypes in cohorts of children with mild and severe asthma. Furthermore, TNFRSF21 was significantly upregulated in bronchial basal epithelial cells from adults with allergic asthma but not in adults with allergies (but not asthma) after allergen challenge. CONCLUSIONS: We report novel associations between rare variants in genes and allergic and inflammatory phenotypes in children with diverse ancestries, highlighting TNFRSF21 as contributing to the development of allergic asthma.
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Asma , Hipersensibilidad , Adulto , Niño , Humanos , Animales , Ratones , Asma/genética , Hipersensibilidad/genética , Estudios de Asociación Genética , Fenotipo , Alérgenos , Polimorfismo de Nucleótido Simple , Estudio de Asociación del Genoma Completo , Receptores del Factor de Necrosis TumoralRESUMEN
BACKGROUND: Sleep disordered breathing (SDB) may exacerbate asthma and is a treatable comorbidity. OBJECTIVE: To design and implement a screening process for SDB in patients hospitalized for asthma exacerbation using quality improvement (QI) methods. We sought to improve screening for SDB from zero to 60% from July 2019 to December 2020. DESIGN/METHODS: A multidisciplinary team used QI methods to screen for SDB using the Michigan pediatric sleep questionnaire (PSQ) in patients 2-18 years hospitalized for asthma exacerbation. Key interventions included: pairing the PSQ screen with another element of routine care (the asthma risk factor screen), educating staff and physicians, engaging respiratory therapists to complete the PSQ and document scores, and modifying the electronic medical record (asthma order set and flowsheet for PSQ score documentation). A run chart tracked progress and descriptive statistics were generated. RESULTS: There were 2067 patients admitted for asthma exacerbation during this project. The PSQ was completed for 1531 patients (74%) overall. Of screened patients, 360 (24%) had a positive PSQ; the mean age was 8.6 years. Approximately 14 months after the project began, ~90% of children admitted for asthma were being screened; subsequently, >80% of patients were being screened until May 2022. Screening with the PSQ occurred approximately 90% of the time when routine asthma risk screens were completed. CONCLUSION: A screening process for SDB was successfully implemented and appeared feasible and sustainable. The high proportion of positive screens reinforces the importance of evaluating for SDB in the high-risk population of children requiring hospitalization for asthma exacerbation.
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Asma , Síndromes de la Apnea del Sueño , Niño , Humanos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/epidemiología , Sueño , Comorbilidad , Asma/complicaciones , Asma/diagnóstico , Asma/epidemiología , Encuestas y CuestionariosRESUMEN
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 PM2·5, PM10, O3, NO2, SO2, 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 PM2·5 and O3 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 PM2·5 with increased epithelial induction of tissue kallikreins, mucus hypersecretion, and barrier functions and O3 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.
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Contaminantes Atmosféricos , Contaminación del Aire , Asma , Humanos , Masculino , Niño , Femenino , Adolescente , Estados Unidos/epidemiología , Contaminantes Atmosféricos/análisis , Estudios Retrospectivos , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Asma/epidemiología , Material Particulado/análisisRESUMEN
BACKGROUND: Asthma is the most common chronic disease in children, occurring at higher frequencies and with more severe disease in children with African ancestry. METHODS: We tested for association with haplotypes at the most replicated and significant childhood-onset asthma locus at 17q12-q21 and asthma in European American and African American children. Following this, we used whole-genome sequencing data from 1060 African American and 100 European American individuals to identify novel variants on a high-risk African American-specific haplotype. We characterized these variants in silico using gene expression and ATAC-seq data from airway epithelial cells, functional annotations from ENCODE, and promoter capture (pc)Hi-C maps in airway epithelial cells. Candidate causal variants were then assessed for correlation with asthma-associated phenotypes in African American children and adults. RESULTS: Our studies revealed nine novel African-specific common variants, enriched on a high-risk asthma haplotype, which regulated the expression of GSDMA in airway epithelial cells and were associated with features of severe asthma. Using ENCODE annotations, ATAC-seq, and pcHi-C, we narrowed the associations to two candidate causal variants that are associated with features of T2 low severe asthma. CONCLUSIONS: Previously unknown genetic variation at the 17q12-21 childhood-onset asthma locus contributes to asthma severity in individuals with African ancestries. We suggest that many other population-specific variants that have not been discovered in GWAS contribute to the genetic risk for asthma and other common diseases.
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Asma , Negro o Afroamericano , Negro o Afroamericano/genética , Alelos , Asma/genética , Asma/metabolismo , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Proteínas Citotóxicas Formadoras de PorosRESUMEN
OBJECTIVES: Dexamethasone is increasingly used for the management of children hospitalized with asthma in place of prednisone, yet data regarding the effectiveness of dexamethasone in children with asthma exacerbation severe enough to require hospitalization are limited. Our objective is to compare the effectiveness of dexamethasone versus prednisone in children hospitalized with an asthma exacerbation on 30-day reutilization. METHODS: We conducted a retrospective cohort study at an urban, quaternary children's hospital of children aged 4 to 17 years, hospitalized from January 1, 2014 to December 31, 2017, with a primary discharge diagnosis of asthma. A covariate-balanced propensity score was derived to account for physician discretion in steroid selection. A generalized linear model, including inverse probability treatment weighting, was used to detect differences in 30-day return utilization (unplanned readmission or emergency department visit) between children whose first dose of corticosteroid was dexamethasone versus prednisone. RESULTS: Inclusion criteria were met by 1161 patients, of which 510 (44%) first received dexamethasone versus 651 (56%) who first received prednisone. The total cohort had a mean age of 8.5 years (SD 3.4). The covariate-balanced cohort had no significant differences in demographic characteristics or illness severity between groups. The dexamethasone group had a return utilization of 3.9% (20 of 510) versus 2.2% (14 of 651) for children treated with prednisone. The propensity score-adjusted analysis revealed the steroid treatment was not found to significantly affect the 30-day reutilization (adjusted odds ratio [aOR] 1.61; 95%CI 0.80-3.31). CONCLUSIONS: The initial steroid choice (dexamethasone versus prednisone) was not associated with 30-day reutilization after hospitalization for an asthma exacerbation.
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Asma , Dexametasona , Adolescente , Asma/diagnóstico , Asma/tratamiento farmacológico , Niño , Preescolar , Dexametasona/uso terapéutico , Hospitalización , Humanos , Prednisona/uso terapéutico , Estudios RetrospectivosRESUMEN
BACKGROUND: Seasonal variation in respiratory illnesses and exacerbations in pediatric populations with asthma is well described, though whether upper airway microbes play season-specific roles in these events is unknown. OBJECTIVE: We hypothesized that nasal microbiota composition is seasonally dynamic and that discrete microbe-host interactions modify risk of asthma exacerbation in a season-specific manner. METHODS: Repeated nasal samples from children with exacerbation-prone asthma collected during periods of respiratory health (baseline; n = 181 samples) or first captured respiratory illness (n = 97) across all seasons, underwent bacterial (16S ribosomal RNA gene) and fungal (internal transcribed spacer region 2) biomarker sequencing. Virus detection was performed by multiplex PCR. Paired nasal transcriptome data were examined for seasonal dynamics and integrative analyses. RESULTS: Upper airway bacterial and fungal microbiota and rhinovirus detection exhibited significant seasonal dynamics. In seasonally adjusted analysis, variation in both baseline and respiratory illness microbiota related to subsequent exacerbation. Specifically, in the fall, when respiratory illness and exacerbation events were most frequent, several Moraxella and Haemophilus members were enriched both in virus-positive respiratory illnesses and those that progressed to exacerbations. The abundance of 2 discrete bacterial networks, characteristically comprising either Streptococcus or Staphylococcus, exhibited opposing interactions with an exacerbation-associated SMAD3 nasal epithelial transcriptional module to significantly increase the odds of subsequent exacerbation (odds ratio = 14.7, 95% confidence interval = 1.50-144, P = .02; odds ratio = 39.17, 95% confidence interval = 2.44-626, P = .008, respectively). CONCLUSIONS: Upper airway microbiomes covary with season and with seasonal trends in respiratory illnesses and asthma exacerbations. Seasonally adjusted analyses reveal specific bacteria-host interactions that significantly increase risk of asthma exacerbation in these children.
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Asma , Microbiota , Virosis , Asma/microbiología , Bacterias/genética , Niño , Humanos , Rhinovirus , Estaciones del Año , TranscriptomaRESUMEN
BACKGROUND: Asthma is heterogeneous, contributing to difficulty in disease management. OBJECTIVE: To develop a biomarker-informed treatment model for difficult-to-treat (DTT) asthma and conduct a pilot feasibility study. METHODS: School-aged children (n = 21) with DTT asthma were enrolled and completed 3 medical visits (V1-V3). V2 and V3 were completed approximately 3.5 months and 12 months after V1, respectively. At V1, guideline care and adherence interventions were initiated, and blood samples were collected for asthma biomarker assessment. A personalized treatment algorithm was developed based on biomarkers (treatment by endotype) and was implemented at V2. Asthma outcomes were compared from V1 to V2 (guideline-based care) to V2 to V3 (guideline + biomarker-informed care). RESULTS: Overall retention was 86%. There was an even distribution of participants with allergy, without allergy, and with mixed allergies. The participants received an average of 5.9 interventions (range, 3-9). The allergic phenotype was characterized by increased CDHR3 risk genotype and high transepidermal water loss. High serum interleukin-6 level was most notable in the mixed allergic subgroup. The nonallergic phenotype was characterized by vitamin D deficiency and poor steroid treatment responsiveness. The personalized treatment plans were associated with decreased emergency department visits (median, 1 vs 0; P = .04) and increased asthma control test scores (median, 22.5 vs 23.0; P = .01). CONCLUSION: The biomarker-based treatment algorithm triggered interventions on top of guideline care in all children with DTT asthma studied, supporting the need for this type of multipronged approach. Our findings identify the minimal biomarker set that is informative, reveal that this treatment-by-endotype intervention is feasible and may be superior to guideline care alone, and provide a strong foundation for a definitive trial. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04179461.
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Asma , Hipersensibilidad , Asma/diagnóstico , Asma/terapia , Biomarcadores , Proteínas Relacionadas con las Cadherinas , Cadherinas , Niño , Servicio de Urgencia en Hospital , Humanos , Proteínas de la Membrana , FenotipoRESUMEN
BACKGROUND: Mold sensitization and exposure are associated with asthma severity, but the specific species that contribute to difficult-to-control (DTC) asthma are unknown. OBJECTIVE: We sought to determine the association between overall and specific mold levels in the homes of urban children and DTC asthma. METHODS: The Asthma Phenotypes in the Inner-City study recruited participants, aged 6 to 17 years, from 8 US cities and classified each participant as having either DTC asthma or easy-to-control (ETC) asthma on the basis of treatment step level. Dust samples had been collected in each participant's home (n = 485), and any dust remaining (n = 265 samples), after other analyses, was frozen at -20oC. The dust samples (n = 265) were analyzed using quantitative PCR to determine the concentrations of the 36 molds in the Environmental Relative Moldiness Index. Logistic regression was performed to discriminate specific mold content of dust from homes of children with DTC versus ETC asthma. RESULTS: Frozen-dust samples were available from 54% of homes of children with DTC (139 of 253) and ETC asthma (126 of 232). Only the average concentration of the mold Mucor was significantly (P < .001) greater in homes of children with DTC asthma. In homes with window air-conditioning units, the Mucor concentration contributed about a 22% increase (1.6 odds ratio; 95% CI, 1.2-2.2) in the ability to discriminate between cases of DTC and ETC asthma. CONCLUSIONS: Mucor levels in the homes of urban youth were a predictor of DTC asthma, and these higher Mucor levels were more likely in homes with a window air-conditioner.
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Contaminación del Aire Interior , Asma , Adolescente , Contaminación del Aire Interior/análisis , Alérgenos , Asma/epidemiología , Polvo/análisis , Hongos , Vivienda , Humanos , Población UrbanaRESUMEN
BACKGROUND: Characterization of allergic responses to cockroach (CR), a common aeroallergen associated with asthma, has focused mainly on IgE reactivity, but little is known about T cell responses, particularly in children. We conducted a functional evaluation of CR allergen-specific T cell reactivity in a cohort of CR allergic children with asthma. METHODS: Peripheral blood mononuclear cells (PBMCs) were obtained from 71 children, with mild-to-moderate asthma who were enrolled in a CR immunotherapy (IT) clinical trial, prior to treatment initiation. PBMC were stimulated with peptide pools derived from 11 CR allergens, and CD4+ T cell responses assessed by intracellular cytokine staining. RESULTS: Highly heterogeneous responses in T cell reactivity were observed among participants, both in terms of the magnitude of cytokine response and allergen immunodominance. Reactivity against Bla g 9 and Bla g 5 was most frequent. The phenotype of the T cell response was dominated by IL-4 production and a Th2 polarized profile in 54.9% of participants, but IFNγ production and Th1 polarization was observed in 25.3% of the participants. The numbers of regulatory CD4+ T cells were also highly variable and the magnitude of effector responses and Th2 polarization were positively correlated with serum IgE levels specific to a clinical CR extract. CONCLUSIONS: Our results demonstrate that in children with mild-to-moderate asthma, CR-specific T cell responses display a wide range of magnitude, allergen dominance, and polarization. These results will enable examination of whether any of the variables measured are affected by IT and/or are predictive of clinical outcomes.
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BACKGROUND: Nasal allergen challenge (NAC) could be a means to assess indication and/or an outcome of allergen-specific therapies, particularly for perennial allergens. NACs are not commonly conducted in children with asthma, and cockroach NACs are not well established. This study's objective was to identify a range of German cockroach extract doses that induce nasal symptoms and to assess the safety of cockroach NAC in children with asthma. METHODS: Ten adults (18-37 years) followed by 25 children (8-14 years) with well-controlled, persistent asthma and cockroach sensitization underwent NAC with diluent followed by up to 8 escalating doses of cockroach extract (0.00381-11.9 µg/mL Bla g 1). NAC outcome was determined by Total Nasal Symptom Score (TNSS) and/or sneeze score. Cockroach allergen-induced T-cell activation and IL-5 production were measured in peripheral blood mononuclear cells. RESULTS: 67% (6/9) of adults and 68% (17/25) of children had a positive NAC at a median response dose of 0.120 µg/mL [IQR 0.0380-0.379 µg/mL] of Bla g 1. Additionally, three children responded to diluent alone and did not receive any cockroach extract. Overall, 32% (11/34) were positive with sneezes alone, 15% (5/34) with TNSS alone, and 21% (7/34) with both criteria. At baseline, NAC responders had higher cockroach-specific IgE (P = .03), lower cockroach-specific IgG/IgE ratios (children, P = .002), and increased cockroach-specific IL-5-producing T lymphocytes (P = .045). The NAC was well tolerated. CONCLUSION: We report the methodology of NAC development for children with persistent asthma and cockroach sensitization. This NAC could be considered a tool to confirm clinically relevant sensitization and to assess responses in therapeutic studies.
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Asma , Cucarachas , Alérgenos , Animales , Asma/tratamiento farmacológico , Niño , Humanos , Leucocitos Mononucleares , Pruebas de Provocación NasalRESUMEN
BACKGROUND: Perennial aeroallergen sensitization is associated with greater asthma morbidity and is required for treatment with omalizumab. OBJECTIVE: To investigate the predictive relationship between the number of aeroallergen sensitizations, total serum IgE, and serum eosinophil count, and response to omalizumab in children and adolescents with asthma treated during the fall season. METHODS: This analysis includes inner-city patients with persistent asthma and recent exacerbations aged 6-20 years comprising the placebo- and omalizumab-treated groups in 2 completed randomized clinical trials, the Inner-City Anti-IgE Therapy for Asthma study and the Preventative Omalizumab or Step-Up Therapy for Fall Exacerbations study. Logistic regression modeled the relationship between greater degrees of markers of allergic inflammation and the primary outcome of fall season asthma exacerbations. RESULTS: The analysis included 761 participants who were 62% male and 59% African American with a median age of 10 years. Fall asthma exacerbations were significantly higher in children with greater numbers of aeroallergen-specific sensitizations in the placebo group (odds ratio [OR], 1.33; 95% confidence interval [CI], 1.11-1.60; P < .01), but not in the omalizumab-treated children (OR, 1.08; 95% CI, 0.91-1.28; P = .37), indicating a significant differential effect (P < .01). Likewise, there was a differential effect of omalizumab treatment in children with greater baseline total serum IgE levels (P < .01) or greater baseline serum eosinophil counts (P < .01). Multiple aeroallergen sensitization was the best predictor of response to omalizumab; treated participants sensitized to ≥4 different groups of aeroallergens had a 51% reduction in the odds of a fall exacerbation (OR, 0.49; 95% CI, 0.30-0.81; P < .01). CONCLUSIONS: In preventing fall season asthma exacerbations, treatment with omalizumab was most beneficial in children with a greater degree of allergic inflammation.
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Antiasmáticos , Asma , Eosinofilia , Adolescente , Adulto , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Asma/epidemiología , Niño , Femenino , Humanos , Inmunoglobulina E , Masculino , Omalizumab/uso terapéutico , Estaciones del Año , Adulto JovenRESUMEN
Objective: Little is known about weight status and its effects on clinical course during hospitalization for asthma exacerbation. We sought to evaluate associations between weight status, specifically body mass index (BMI), with inpatient clinical course and clinical history.Methods: We retrospectively analyzed data from 2012 to 2013 on children hospitalized for asthma exacerbation in a state-wide longitudinal cohort, the Ohio Pediatric Asthma Repository. We examined BMI continuously (z scores) and categorically, comparing overweight and obese (Ov/Ob) to non-overweight and non-obese (nOv/nOb) children. We used linear mixed models controlling for site effects to determine if BMI was related to length of stay, as determined by physiologic readiness for discharge (PRD), defined as time to albuterol spaced every 4 h, need for nonstandard care or clinical history.Results: Across six hospitals, 874 children were included in analyses. BMI was positively associated with PRD (p=.008) but this increase was unlikely to be clinically significant. Ov/Ob children were more likely than nOv/nOb to require nonstandard care with repeat magnesium dosing in intensive care after dosing in the emergency department (OR = 3.23, 95%CI 1.39-7.78). Hospitalization in the year prior to enrollment was positively associated with BMI percentile (73.3 vs. 66.0, p=.028). Sleep disordered breathing was also associated with higher BMI percentile (78.2 vs. 65.9; p=.0013).Conclusions: Ov/Ob children had similar PRD to nOv/nOb children and were prone to repeat magnesium dosing. Previous hospitalization for exacerbation was positively associated with increasing BMI percentile. Additional research should investigate differential magnesium use by weight status, quantifying risks and benefits.
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Albuterol/uso terapéutico , Asma/tratamiento farmacológico , Magnesio/administración & dosificación , Obesidad/epidemiología , Sobrepeso/epidemiología , Adolescente , Asma/complicaciones , Asma/diagnóstico , Índice de Masa Corporal , Niño , Preescolar , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Estudios Longitudinales , Masculino , Obesidad/complicaciones , Obesidad/diagnóstico , Ohio/epidemiología , Sobrepeso/complicaciones , Sobrepeso/diagnóstico , Alta del Paciente/estadística & datos numéricos , Estudios Prospectivos , Sistema de Registros/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Brote de los Síntomas , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: In infants, distinct nasopharyngeal bacterial microbiotas differentially associate with the incidence and severity of acute respiratory tract infection and childhood asthma development. OBJECTIVE: We hypothesized that distinct nasal airway microbiota structures also exist in children with asthma and relate to clinical outcomes. METHODS: Nasal secretion samples (n = 3122) collected after randomization during the fall season from children with asthma (6-17 years, n = 413) enrolled in a trial of omalizumab (anti-IgE) underwent 16S rRNA profiling. Statistical analyses with exacerbation as the primary outcome and rhinovirus infection and respiratory illnesses as secondary outcomes were performed. Using A549 epithelial cells, we assessed nasal isolates of Moraxella, Staphylococcus, and Corynebacterium species for their capacity to induce epithelial damage and inflammatory responses. RESULTS: Six nasal airway microbiota assemblages, each dominated by Moraxella, Staphylococcus, Corynebacterium, Streptococcus, Alloiococcus, or Haemophilus species, were observed. Moraxella and Staphylococcus species-dominated microbiotas were most frequently detected and exhibited temporal stability. Nasal microbiotas dominated by Moraxella species were associated with increased exacerbation risk and eosinophil activation. Staphylococcus or Corynebacterium species-dominated microbiotas were associated with reduced respiratory illness and exacerbation events, whereas Streptococcus species-dominated assemblages increased the risk of rhinovirus infection. Nasal microbiota composition remained relatively stable despite viral infection or exacerbation; only a few taxa belonging to the dominant genera exhibited relative abundance fluctuations during these events. In vitro, Moraxella catarrhalis induced significantly greater epithelial damage and inflammatory cytokine expression (IL-33 and IL-8) compared with other dominant nasal bacterial isolates tested. CONCLUSION: Distinct nasal airway microbiotas of children with asthma relate to the likelihood of exacerbation, rhinovirus infection, and respiratory illnesses during the fall season.
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Asma/microbiología , Eosinófilos/inmunología , Microbiota/genética , Mucosa Nasal/microbiología , ARN Ribosómico 16S/análisis , Sistema Respiratorio/patología , Infecciones del Sistema Respiratorio/microbiología , Células A549 , Adolescente , Asma/inmunología , Muerte Celular , Niño , Progresión de la Enfermedad , Femenino , Humanos , Lactante , Inflamación , Masculino , Mucosa Nasal/inmunología , Infecciones del Sistema Respiratorio/inmunologíaRESUMEN
Respiratory infections are common precursors to asthma exacerbations in children, but molecular immune responses that determine whether and how an infection causes an exacerbation are poorly understood. By using systems-scale network analysis, we identify repertoires of cellular transcriptional pathways that lead to and underlie distinct patterns of asthma exacerbation. Specifically, in both virus-associated and nonviral exacerbations, we demonstrate a set of core exacerbation modules, among which epithelial-associated SMAD3 signaling is upregulated and lymphocyte response pathways are downregulated early in exacerbation, followed by later upregulation of effector pathways including epidermal growth factor receptor signaling, extracellular matrix production, mucus hypersecretion, and eosinophil activation. We show an additional set of multiple inflammatory cell pathways involved in virus-associated exacerbations, in contrast to squamous cell pathways associated with nonviral exacerbations. Our work introduces an in vivo molecular platform to investigate, in a clinical setting, both the mechanisms of disease pathogenesis and therapeutic targets to modify exacerbations.
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Asma/inmunología , Redes Reguladoras de Genes/inmunología , Transcriptoma/inmunología , Virosis/inmunología , Adolescente , Asma/genética , Asma/virología , Estudios de Casos y Controles , Niño , Resfriado Común/genética , Resfriado Común/inmunología , Resfriado Común/virología , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Transducción de Señal/genética , Transducción de Señal/inmunología , Virosis/genética , Virosis/virologíaRESUMEN
Asthma is a complex heterogeneous disease characterized by reversible airflow obstruction. After appropriate diagnosis, the management in school-aged children centers on 3 broad domains: pharmacologic treatment, treatment of underlying comorbidities, and education of the patient and caregivers. It is important to understand that the phenotypic differences that exist in the school-aged child with asthma may impact underlying comorbid conditions as well as pharmacologic treatment choices. Following initiation of therapy, asthma control must be continually evaluated in order to optimize management.
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Asma/epidemiología , Asma/diagnóstico , Asma/terapia , Cuidadores , Niño , Preescolar , Comorbilidad , Humanos , Infiltración Neutrófila , Medicina de Precisión , Calidad de Vida , Pruebas de Función Respiratoria , Ruidos Respiratorios , Estados Unidos/epidemiologíaRESUMEN
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. FEV1 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.
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Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Toma de Decisiones Asistida por Computador , Guías de Práctica Clínica como Asunto/normas , Adolescente , Adulto , Asma/diagnóstico , Asma/epidemiología , Niño , Práctica Clínica Basada en la Evidencia , Femenino , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Estados Unidos/epidemiología , Población Urbana , Adulto JovenRESUMEN
BACKGROUND: Rhinitis and asthma are linked, but substantial knowledge gaps in this relationship exist. OBJECTIVE: We sought to determine the prevalence of rhinitis and its phenotypes in children and adolescents with asthma, assess symptom severity and medication requirements for rhinitis control, and investigate associations between rhinitis and asthma. METHODS: Seven hundred forty-nine children with asthma participating in the Asthma Phenotypes in the Inner-City study received baseline evaluations and were managed for 1 year with algorithm-based treatments for rhinitis and asthma. Rhinitis was diagnosed by using a questionnaire focusing on individual symptoms, and predefined phenotypes were determined by combining symptom patterns with skin tests and measurement of serum specific IgE levels. RESULTS: Analyses were done on 619 children with asthma who completed at least 4 of 6 visits. Rhinitis was present in 93.5%, and phenotypes identified at baseline were confirmed during the observation/management year. Perennial allergic rhinitis with seasonal exacerbations was most common (34.2%) and severe. Nonallergic rhinitis was least common (11.3%) and least severe. The majority of children remained symptomatic despite use of nasal corticosteroids with or without oral antihistamines. Rhinitis was worse in patients with difficult-to-control versus easy-to-control asthma, and its seasonal patterns partially corresponded to those of difficult-to-control asthma. CONCLUSION: Rhinitis is almost ubiquitous in urban children with asthma, and its activity tracks that of lower airway disease. Perennial allergic rhinitis with seasonal exacerbations is the most severe phenotype and most likely to be associated with difficult-to-control asthma. This study offers strong support to the concept that rhinitis and asthma represent the manifestations of 1 disease in 2 parts of the airways.