Inner city asthma

Short Report: Exploring the Effect of Prenatal Fatty Acid Supplementation on Wheeze and Asthma in Black American Children

Background

Black American children are at higher risk for developing asthma than White children. Identifying potential scalable preventive interventions that can reduce the racial disparities in asthma prevalence and associated morbidity and mortality are needed. We leveraged data from an RCT of prenatal supplementation with docosahexaenoic acid (DHA) in Black American women, to explore whether prenatal fatty acid supplementation is associated with offspring wheeze and asthma.

Methods

Data were from the Nutrition and Pregnancy Study (NAPS), a double-blind RCT of prenatal DHA supplementation in Black women targeting stress regulation during pregnancy. A subset of mothers (n = 83) completed a standardized questionnaire on offspring wheeze and asthma when children were between 0.5 and 5.5 years of age. DHA levels were measured from venous blood and reported as percent of total fatty acids.

Results

Of the 83 mothers providing data on child wheeze and asthma, 57 (68.7%) had been randomized to active DHA and 26 (31.3%) to placebo. Mothers and research staff were blind to group assignment. Comparison at the group assignment level yielded a relative reduction of 32% in the rate of wheeze or asthma among offspring of mothers assigned to active DHA compared to offspring of mothers assigned to placebo (OR = 1.6 [95% CI = 0.50-5.09], p = 0.426). DHA levels measured at 25-29 and 33-37 weeks of gestation differed as a function of offspring wheeze or asthma (t = 2.21, p = 0.015 and t = 2.54, p = 0.007, respectively).

Conclusion

These preliminary data suggest that increasing prenatal levels of DHA could be considered as a potential prevention for asthma in Black American children.

Contribution of caregiver and child anxiety and depressive symptoms to child asthma-related quality of life

BACKGROUND

Depression and anxiety negatively affect asthma-related quality of life (QoL). Yet, little is known regarding mood and asthma-related factors that best uniquely explain asthma-related QoL in children.

OBJECTIVE

This cross-sectional study evaluated the unique variance explained by caregiver and child depressive and anxiety symptom severity in child asthma-related QoL, apart from that explained by demographics and asthma control.

METHODS

Children aged 7 to 17 years with asthma (n = 205) and their caregivers with major depressive disorder were included. A 3-stage hierarchical linear regression analysis was conducted with the Pediatric Asthma Quality of Life Questionnaire total scores considered as the outcome. Predictors included demographic characteristics (stage 1); asthma control assessed by the Asthma Control Test (stage 2); and caregiver depression and anxiety (Hamilton Rating Scale for Depression and the Spielberger State/Trait Anxiety Scale) and child depression and anxiety (Children's Depression Inventory and the Screen for Child Anxiety-Related Disorders) (stage 3).

RESULTS

Demographic characteristics accounted for only 5.5% of the Pediatric Asthma Quality of Life Questionnaire scores. Asthma control significantly increased variance explained in QoL to 32.6%, whereas caregiver and child depression and anxiety symptoms significantly increased variance explained to 42.6%. Child anxiety was found to uniquely explain the largest proportion of variance in QoL (rs2 = 0.584).

CONCLUSION

After adjusting variance in QoL for demographic characteristics and asthma control, caregiver and child depression and anxiety measures significantly increased the proportion of variance explained in a child's asthma-related QoL. In addition to better asthma control, child and caregiver depression and anxiety should be addressed to increase child asthma-related QoL.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02809677.

Type 2 Inflammation and Asthma in Children: A Narrative Review

Increased understanding of the underlying pathophysiology has highlighted the heterogeneity of asthma and identified that most children with asthma have type 2 inflammation with elevated biomarkers, such as blood eosinophils and/or fractional exhaled nitric oxide. Although in the past most of these children may have been categorized as having allergic asthma, identifying the type 2 inflammatory phenotype provides a mechanism to explain both allergic and non-allergic triggers in pediatric patients with asthma. Most children achieve control with low to medium doses of inhaled corticosteroids. However, in a small but significant proportion of children, asthma remains uncontrolled despite maximum conventional treatment, with an increased risk of severe exacerbations. In this review, we focus on the role of type 2 inflammation and allergic processes in children with asthma, together with evidence of the efficacy of available treatment options for those who experience severe symptoms.

Respiratory disease patterns in rural Western Uganda, 2019-2022

Introduction

Respiratory disease is a major cause of morbidity and mortality in the developing world, but prospective studies of temporal patterns and risk factors are rare.

Methods

We studied people in rural Western Uganda, where respiratory disease is pervasive. We followed 30 adults (ages 22-51 years; 534 observations) and 234 children (ages 3-11 years; 1,513 observations) between May 2019 and July 2022 and collected monthly data on their respiratory symptoms, for a total of 2,047 case records. We examined associations between demographic and temporal factors and respiratory symptoms severity.

Results

The timing of our study (before, during, and after the emergence of COVID-19) allowed us to document the effects of public health measures instituted in the region. Incidence rates of respiratory symptoms before COVID-19 lockdown were 568.4 cases per 1,000 person-months in children and 254.2 cases per 1,000 person-months in adults. These rates were 2.6 times higher than the 2019 global average for children but comparable for adults. Younger children (ages 3-6 years) had the highest frequencies and severities of respiratory symptoms. Study participants were most likely to experience symptoms in February, which is a seasonal pattern not previously documented. Incidence and severity of symptoms in children decreased markedly during COVID-19 lockdown, illustrating the broad effects of public health measures on the incidence of respiratory disease.

Discussion

Our results demonstrate that patterns of respiratory disease in settings such as Western Uganda resemble patterns in developed economies in some ways (age-related factors) but not in others (increased incidence in children and seasonal pattern). Factors such as indoor air quality, health care access, timing of school trimesters, and seasonal effects (rainy/dry seasons) likely contribute to the differences observed.

Impact of steroids on the immune profiles of children with asthma living in the inner-city

Background: Inner-city asthma is associated with high morbidity and systemic steroid use. Chronic steroid use impacts immune function; however, there is a lack of data with regard to the extent of immunosuppression in patients with asthma and who are receiving frequent systemic steroids. Objective: To identify the impact of frequent systemic steroid bursts on the immune function of children with asthma who live in the inner city. Methods: Children ages 3-18 years with asthma were divided into study (≥2 systemic steroid bursts/year) and control groups (0-1 systemic steroid bursts/year). Lymphocyte subsets; mitogen proliferation assay; total immunoglobulin G (IgG) value, and pneumococcal and diphtheria/tetanus IgG values were evaluated. Results: Ninety-one participants were enrolled (study group [n = 42] and control group [n = 49]). There was no difference in adequate pneumococcal IgG value, diphtheria/tetanus IgG value, mitogen proliferation assays, lymphocyte subsets, and IgG values between the two groups. Children who received ≥2 steroid bursts/year had a significantly lower median pneumococcal IgG serotype 7F value. Most of the immune laboratory results were normal except for the pneumococcal IgG value. Most of the participants (n/N = 72/91 [79%]) had an inadequate pneumococcal IgG level (<7/14 serotypes ≥1.3 µg/mL). The participants with inadequate pneumococcal IgG level and who received a pneumococcal polysaccharide vaccine 23 (PPSV23) boost had a robust response. There was no significant difference in infection, steroid exposure, asthma severity, or morbidities between those with adequate versus inadequate pneumococcal IgG values. Conclusion: Children with asthma who live in the inner city and receive ≥2 steroid bursts/year do not have a significantly different immune profile from those who receive ≤1 steroid bursts/year do not have a significantly different immune profile from those who do not. Although appropriately vaccinated, most participants had an inadequate pneumococcal IgG level, regardless of steroid exposure and asthma severity. These children may benefit from PPSV23.

Anxiety, depression and global distress among African American young adults with uncontrolled asthma

BACKGROUND

Anxiety and depression are mental health disorders that are often comorbid with asthma. Urban African American young adults with asthma often experience increased risk of anxiety and depression.

OBJECTIVE

To explore relationships between symptoms of psychological distress and asthma-related anxiety with asthma outcomes among urban African American young adults with poorly controlled persistent asthma.

METHODS

A secondary analysis of baseline data from a larger study of 141 African American young adults with uncontrolled persistent asthma was examined. Participants completed the Brief Symptom Inventory (BSI-18), Youth Asthma-related Anxiety Scale, Asthma Control Test (ACT), a daily diary to assess asthma symptoms; and number of asthma attacks. Spirometry assessed airway obstruction. Generalized linear models tested associations.

RESULTS

In multivariable models testing, higher somatization scores were significantly associated with lower ACT scores (adjusted β = -0.49; 95% CI = -0.69, -0.28; p < 0.01), and higher symptoms (adjusted β = 0.39; 95% CI = 0.14, 0.65; p < 0.01). After adding asthma-related anxiety to the model, the somatization subscale and asthma-related anxiety were significantly associated with ACT scores (adjusted β = -0.36; 95% CI = -0.57, -0.15; p < 0.01), (adjusted β = -0.32; 95% CI = -0.50, -0.14; p < 0.01), respectively. Asthma-related anxiety was also significantly associated with asthma attacks (adjusted β = 0.24; 95% CI = 0.05, 0.43; p < 0.05).

CONCLUSION

This study suggests, asthma-related anxiety may differ from general anxiety and be related to poorly controlled asthma among African American young adults.

Associations between outdoor air pollutants and non-viral asthma exacerbations and airway inflammatory responses in children and adolescents living in urban areas in the USA: a retrospective secondary analysis

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.

Community Interventions for Childhood Asthma ED Visits and Hospitalizations: A Systematic Review

A systematic review of interventions in community environments found significant reductions in childhood asthma exacerbations leading to emergency department visits and hospitalizations.

BACKGROUND AND OBJECTIVES

Structural and social determinants of childhood asthma inequities manifest within geographic communities that are often segregated. Childhood asthma disproportionately affects Black, Hispanic, and low-income populations. Community interventions have the potential to improve inequities in emergency healthcare. This systematic review was conducted to assess the effectiveness of childhood asthma community interventions and provide a conceptual model to inform implementation of future community interventions.

METHODS

Publications from PubMed, ScienceDirect, CINAHL, Cochrane Library, Web of Science, and hand searched references were examined from 2010 to 2021. Community intervention studies among children with asthma were included. Main outcomes were emergency department visits and hospitalizations. Community interventions exclusively focusing on schools or hospitals were excluded. Two reviewers independently assessed eligibility for final inclusion. Emergency healthcare findings were extracted in addition to co-benefits (eg, fewer missed school days and caregiver workdays).

RESULTS

Out of 1856 records, 26 publications met the inclusion criteria. Community interventions were categorized by care coordination (n = 8), policy and environmental changes (eg, smoke-free legislature, traffic reduction models, and green housing) (n = 8), home-based (n = 6), and community-based health services (n = 4). Selected studies indicated that community interventions significantly reduced childhood asthma emergency department visits and hospitalizations through increased caregiver self-efficacy, home environmental trigger reduction, and increased access to healthcare. Because of heterogeneity among studies, we were unable to conduct a meta-analysis.

CONCLUSIONS

Findings show significant associations between community interventions and the reduction of emergency healthcare, suggesting a protective effect for severe cases of childhood asthma.

Clinical Outcomes for Young Children Diagnosed With Asthma Versus Reactive Airway Disease

OBJECTIVE

Clinical diagnoses of asthma and reactive airway disease (RAD) in young children are subjective. We examined how often children were diagnosed with asthma versus RAD, and whether preventive care and 2-year clinical outcomes differed based on initial diagnosis.

METHODS

We conducted a retrospective cohort analysis of children (2-7 years) from a university-based general pediatrics practice who had been diagnosed with RAD or asthma. We performed adjusted comparisons between groups for time until subsequent asthma-related care. We also compared delivery of asthma-related healthcare services, corticosteroid and controller prescriptions, and action plans within 2 years of index diagnosis, using bivariate and regression analyses.

RESULTS

Four hundred three children were included (64% male, 67% Black, 25% Hispanic). RAD was diagnosed in 62% of index visits, and was more likely than asthma to be diagnosed in emergency settings. In the full sample, the time between index visit and subsequent asthma care did not differ between groups, after adjustment for index location. For subjects with complete 24-month follow-up (N = 300), no between-group differences were found in adjusted analyses. Most children with RAD received action plans and controller medications only after a subsequent asthma diagnosis, on average, 9 months after their index visit.

CONCLUSIONS

RAD diagnoses were linked to delayed delivery of preventive care measures, but within 2 years of initial diagnosis, clinical outcomes for those diagnosed with RAD and asthma did not differ. To facilitate clear communication and timely treatment, a prompt diagnosis of asthma, rather than RAD, should be considered for children with asthma symptoms.

Pediatric asthma incidence rates in the United States from 1980 to 2017

BACKGROUND

Few studies have examined longitudinal asthma incidence rates (IRs) from a public health surveillance perspective.

OBJECTIVE

Our aim was to calculate descriptive asthma IRs in children over time with consideration for demographics and parental asthma history.

METHODS

Data from 9 US birth cohorts were pooled into 1 population covering the period from 1980 to 2017. The outcome was earliest parental report of a doctor diagnosis of asthma. IRs per 1,000 person-years were calculated.

RESULTS

The racial/ethnic backgrounds of the 6,283 children studied were as follows: 55% European American (EA), 25.5% African American (AA), 9.5% Mexican-Hispanic American (MA) and 8.5% Caribbean-Hispanic American (CA). The average follow-up was 10.4 years (SD = 8.5 years; median = 8.4 years), totaling 65,291 person-years, with 1789 asthma diagnoses yielding a crude IR of 27.5 per 1,000 person-years (95% CI = 26.3-28.8). Age-specific rates were highest among children aged 0 to 4 years, notably from 1995 to 1999, with a decline in EA and MA children in 2000 to 2004 followed by a decline in AA and CA children in 2010 to 2014. Parental asthma history was associated with statistically significantly increased rates. IRs were similar and higher in AA and CA children versus lower but similar in EA and MA children. The differential rates by sex from birth through adolescence principally resulted from a decline in rates among males but relatively stable rates among females.

CONCLUSIONS

US childhood asthma IRs varied dramatically by age, sex, parental asthma history, race/ethnicity, and calendar year. Higher rates in the 0- to 4-year-olds group, particularly among AA/CA males with a parental history of asthma, as well as changes in rates over time and by demographic factors, suggest that asthma is driven by complex interactions between genetic susceptibility and variation in time-dependent environmental and social factors.

Pediatric Inner-City Asthma

Inner-city children with asthma are known to have high disease mortality and morbidity. Frequently, asthma in this high-risk population is difficult to control and more severe in nature. Several factors, including socioeconomic hardship, ability to access to health care, adherence to medication, exposure to certain allergens, pollution, crowd environment, stress, and infections, play an important role in the pathophysiology of inner-city asthma. Comprehensive control of home allergens and exposure to tobacco smoke, the use of immune based therapies, and school-based asthma programs have shown promising results in asthma control in this population.

Aeroallergen Sensitization, Serum IgE, and Eosinophilia as Predictors of Response to Omalizumab Therapy During the Fall Season Among Children with Persistent Asthma

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.

IFRD1 regulates the asthmatic responses of airway via NF-κB pathway

Asthma is a chronic respiratory disease which is susceptible to children and causes great harm to them. Recently, Interferon-related developmental regulator 1 (IFRD1) was proved to be participant in regulating lung diseases, and its abnormal expression was shown in pathological airway tissues. Our study aimed to demonstrate the role and modulatory mechanism of IFRD1 in the pathogenesis of asthma. First, we evaluated the expression of IFRD1 in the lungs of asthmatic patients. C57BL/6 mice and human bronchial epithelioid (HBE) cells were respectively induced by ovalbumin (OVA) and lipopolysaccharide (LPS) to construct asthma models in vivo and in vitro. Using adenovirus and pcDNA vectors, we carried out overexpression assays on mice and cell models. Additionally, the potential mechanism of IFRD1 on regulating asthma process was elucidated by targeting NF-κB pathway. The results showed that IFRD1 was significantly down-regulated in asthma lung tissues, as well as the in vivo and in vitro models of asthma. Besides, OVA induced the inflammation responses and hyperreactivity of airway in mice, and LPS also caused inflammatory cytokine secretion and apoptosis of HBE cells, while cell viability was inhibited. However, IFRD1 overexpression dramatically reversed the effects of OVA and LPS. We subsequently discovered that the NF-κB pathway was activated in asthmatic cells, and NF-κB signaling activation was involved in IFRD1 regulated asthma responses of HBE cells. In conclusion, our study indicated that IFRD1 inhibited the asthmatic responses of airway via the NF-κB pathway inactivation. The evidence presented herein might provide a novel sight for asthma therapy.

Obesity may enhance the adverse effects of NO2 exposure in urban schools on asthma symptoms in children

BACKGROUND

Sparse data address the effects of nitrogen dioxide (NO₂) exposure in inner-city schools on obese students with asthma.

OBJECTIVE

We sought to evaluate relationships between classroom NO₂ exposure and asthma symptoms and morbidity by body mass index (BMI) category.

METHODS

The School Inner-City Asthma Study enrolled students aged 4 to 13 years with asthma from 37 inner-city schools. Students had baseline determination of BMI percentile. Asthma symptoms, morbidity, pulmonary inflammation, and lung function were monitored throughout the subsequent academic year. Classroom NO₂ data, linked to enrolled students, were collected twice per year. We determined the relationship between classroom NO₂ levels and asthma outcomes by BMI stratification.

RESULTS

A total of 271 predominantly black (35%) or Hispanic students (35%) were included in analyses. Fifty percent were normal weight (5-84th BMI percentile), 15% overweight (≥85-94th BMI percentile), and 35% obese (≥95th BMI percentile). For each 10-parts per billion increase in NO₂, obese students had a significant increase in the odds of having an asthma symptom day (odds ratio [OR], 1.86; 95% CI, 1.15-3.02) and in days caregiver changed plans (OR, 4.24; 95% CI, 2.33-7.70), which was significantly different than normal weight students who exhibited no relationship between NO₂ exposure and symptom days (OR, 0.90; 95% CI, 0.57-1.42; pairwise interaction P = .03) and change in caregiver plans (OR, 1.37; 95% CI, 0.67-2.82; pairwise interaction P = .02). Relationships between NO₂ levels and lung function and fractional exhaled nitric oxide did not differ by BMI category. If we applied a conservative Holm-Bonferroni correction for 16 comparisons (obese vs normal weight and overweight vs normal weight for 8 outcomes), these findings would not meet statistical significance (all P > .003).

CONCLUSIONS

Obese BMI status appears to increase susceptibility to classroom NO₂ exposure effects on asthma symptoms in inner-city children. Environmental interventions targeting indoor school NO₂ levels may improve asthma health for obese children. Although our findings would not remain statistically significant after adjustment for multiple comparisons, the large effect sizes warrant future study of the interaction of obesity and pollution in pediatric asthma.

Phenotypes of wheezing and asthma in preschool children

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the identified phenotypes of preschool wheezing.

RECENT FINDINGS

Early life wheezing patterns have been described in multiple populations, with several commonalities found between cohorts. Early life environmental exposures have been found to be differentially associated with preschool wheezing phenotypes and their future trajectories. These include allergen and microbe exposure, environmental tobacco smoke exposure, and maternal stress and depression. Elevated IgE in early life may also influence future asthma risk.

SUMMARY

Preschool wheezing phenotypes are heterogeneous and complex, with trajectories that are related to factors including environmental exposures. More research is needed to characterize these relationships, hopefully leading to targeted prevention strategies.

Is There Benefit in Identifying Asthma Triggers During an Exacerbation?

Introduction. Allergen-specific IgE (sIgE) testing provides an objective assessment of sensitization to an allergen. Goal. To identify the time when serum measurements of sIgE would be most sensitive. Methods. This was a prospective study conducted between September 1, 2015, and February 25, 2019. Subjects ≥5 and ≤18 years of age, seen in the ED or admitted with an asthma exacerbation, were tested for total IgE and 8 perennial sIgE levels. Subjects with elevated sIgE were tested again after symptom resolution. Results. A total of 104 subjects were enrolled; 50 subjects were eligible for inclusion in the analysis. There were statistically significant differences between the visits for all sIgE, except Alternaria alternatum. Conclusions. In pediatric patients, serum sIgE levels measured during an asthma exacerbation were elevated compared with when their asthma was in better control. sIgE testing during an asthma exacerbation may help identify asthma triggers, mitigate exposure, and hence improve asthma control.

Variability in Diagnosed Asthma in Young Children in a Large Pediatric Primary Care Network

OBJECTIVE

Our objectives were to 1) quantify the frequency of wheezing episodes and asthma diagnosis in young children in a large pediatric primary care network and 2) assess the variability in practice-level asthma diagnosis, accounting for common asthma risk factors and comorbidities. We hypothesized that significant variability in practice-level asthma diagnosis rates would remain after adjusting for associated predictors.

METHODS

We generated a retrospective longitudinal birth cohort of children who visited 1 of 31 pediatric primary care practices within the first 6 months of life from 1/2005 to 12/2016. Children were observed for up to 8 years or until the end of the observation window. We used multivariable discrete time survival models to evaluate predictors of asthma diagnosis by 3-month age intervals. We compared unadjusted and adjusted proportions of children diagnosed with asthma by practice.

RESULTS

Of the 161,502 children in the cohort, 34,578 children (21%) received at least 1 asthma diagnosis. In multivariable modeling, male gender, minority race/ethnicity, gestational age <34 weeks, allergic rhinitis, food allergy, and prior wheezing episodes were associated with asthma diagnosis. After adjusting for variation in these predictors across practices, the cumulative incidence of asthma diagnosis by practice by age 6 years ranged from 11% to 47% (interquartile range: 24%-29%).

CONCLUSIONS

Across pediatric primary care practices, adjusted incidence of asthma diagnosis by age 6 years ranged widely, though variation gauged by the interquartile range was more modest. Potential sources of practice-level variation, such as differing diagnosis thresholds and labeling of different wheezing phenotypes as "asthma," should be further investigated.

Childhood Asthma Inception and Progression: Role of Microbial Exposures, Susceptibility to Viruses and Early Allergic Sensitization

Inappropriate responses to respiratory viruses, especially rhinovirus, and early allergic sensitization are the strongest contributors to the inception and persistence of early onset asthma. The ORMDL3 asthma locus in chromosome 17q seems to exert its effects by increasing susceptibility to human rhinovirus in early life. Being raised on animal farms is highly protective against the development of asthma, and this protective effect is mediated by exposure to microbes. Two trials in high-risk young children, one to prevent wheezing lower respiratory tract illness using bacterial lyophilizates and another using anti-immunoglobulin E to prevent asthma progression, are already under way.

Inner-City Asthma in Childhood

The inner-city is a well-established and well-studied location that includes children at high risk for high asthma prevalence and morbidity. A number of intrinsic and extrinsic risk factors contribute to asthma in inner-city populations. This review seeks to explore these risk factors and evaluate how they contribute to increased asthma morbidity. Previous literature has identified risk factors such as race and ethnicity, prematurity, obesity, and exposure to aeroallergens and pollutants. Environmental and medical interventions aimed at individual risk factors and specific asthma phenotypes have contributed to improved outcomes in the inner-city children with asthma.

New Directions in Pediatric Asthma

Childhood asthma affects many children placing them at significant risk for health care utilization and school absences. Several new developments relevant to the field of pediatric asthma have occurred over the last 5 years; yet, there is much more to learn. It is poorly understood how to prevent the disease, optimally address environmental challenges, or effectively manage poor adherence. Moreover, it is not clear how to customize therapy by asthma phenotype, age group, high risk groups, or severity of disease. Highlights of advances in pediatric asthma are reviewed and multiple essential areas for further exploration and research are discussed.

Nurse-delivered outpatient asthma education for children and caregivers: a pilot study to promote shared asthma management

OBJECTIVES

To assess the feasibility of nurse-delivered asthma education for caregiver/child dyads in a busy clinic setting, and measure the preliminary effectiveness of the intervention.

METHODS

We conducted a pilot study of nurse-delivered asthma education in a busy outpatient clinic. We enrolled a convenience sample of children (7-16 years) with uncontrolled persistent asthma who had a prescription for an inhaled controller medication and public health insurance. After provider visits, nurses taught dyads using picture-based materials, teach-back methods, and colored labels applied to asthma medications. The intervention was repeated at 1-month follow-up. We assessed feasibility by reviewing nurse documentation in the electronic medical record, detailing whether each component was implemented and the time required for education at each visit. We measured preliminary effectiveness by surveying children and caregivers separately before each clinic visit about asthma management responsibility, self-efficacy, caregiver quality of life, and symptoms; caregivers also completed a final telephone survey 2 months after the follow-up visit. We examined pre-post differences in continuous outcomes within-subjects using Wilcoxon signed rank tests.

RESULTS

We enrolled 22 child/caregiver dyads. Nursing documentation indicated a high rate of component delivery at each visit; the initial and 1-month visits required 25 and 15 min, respectively. We observed significant increases in child responsibility, child/caregiver self-efficacy, caregiver quality of life, and child symptoms at each follow-up.

CONCLUSION

This intervention of patient-centered asthma education can be delivered by nurses to caregiver/child dyads with high fidelity in a busy pediatric practice. Preliminary data indicate potential benefit for both children and caregivers.

Applying a biopsychosocial model to inner city asthma: Recent approaches to address pediatric asthma health disparities

Pediatric asthma in inner cities is often severe and children living in these urban locations with socioeconomic disadvantage experience greater asthma morbidity. There are many interconnected risk factors that individually, and in combination, enhance asthma morbidity. These include biologic factors innate to the child, such as genetics and allergen susceptibility, as well as factors related to the family and neighborhood context. The biopsychosocial model can be used to frame these risk factors and develop interventions specific to the inner city. Successful inner city asthma interventions exist and key characteristics include multi-tiered components that operate within the community to coordinate disease management resources between patients, families and health care systems.

Fostering Effective Asthma Self-Management Transfer in High-Risk Children: Gaps and Opportunities for Family Engagement

INTRODUCTION

The process of self-management knowledge, behavior, and skill development in children with asthma from families with low income is understudied.

METHOD

Fifteen mothers of children with uncontrolled asthma participated in semistructured interviews exploring the transfer of asthma self-management responsibilities from parent to child. Team members performed thematic analysis of written transcripts.

RESULTS

All participants were all the biological mothers and were impoverished, with most (73%) reporting an annual family income of less than $30,000. Their children ranged from 5 to 15 years old, were African American (100%), and had uncontrolled asthma based on national guidelines. Themes showed that child asthma self-management is difficult to achieve, that the transfer of asthma responsibility from mother to child is variable, and that mothers overestimate their child's developmental capacities for independent asthma self-management and have poor understanding of what well-controlled asthma means.

DISCUSSION

Ongoing assessment and tailored guidance from health care providers are critical to support the pivotal role of mothers in their child's self-management development process.

Asthma and Attendance in Urban Schools

Introduction

Asthma is linked to student absenteeism, a risk factor for poor achievement and school dropout. Studies of asthma and absenteeism have common limitations, including relying on parent-reported asthma, which may be unreliable and prone to selection, and inadequately accounting for confounding health and social risks. Therefore, the rate of absenteeism attributable to asthma and the extent to which better asthma control would translate into better attendance remain unclear.

Methods

Participants were 1,194 students in 2 large urban US schools (1 elementary, 1 middle) in 2016–2018. Student asthma was assessed based on parent report on health forms, student-reported asthma-related emergency department/hospitalization or medication use, and school health center record of asthma. Multiple imputation was used to reduce selection from missing asthma reports. The relationship between asthma and school district–reported days absent was estimated using Poisson random intercept regression, accounting for health and demographic covariates.

Results

Parent-reported ever asthma (27%) was not associated with absenteeism in adjusted models. Student-reported asthma health care or medication use (16%) and school health center record of asthma (17%) were associated with higher absenteeism (incidence rate ratio [IRR], 1.16; 95% confidence interval [CI], 1.01–1.35 and IRR, 1.21; 95% CI, 1.09–1.34, respectively). Student-reported asthma and school health center record of asthma were associated with 1.9 and 1.5 absences per year, respectively.

Conclusion

Student-reported and school health center record of asthma explained 14% to 18% of student absenteeism, even after accounting for other health and social risks. When possible, student reports should supplement parent reports to ensure that students with asthma are identified and obtain access to care.

Classroom indoor PM2.5 sources and exposures in inner-city schools

Children spend over 6 h a day in schools and have higher asthma morbidity from school environmental exposures. The present study aims to determine indoor and outdoor possible sources affecting indoor PM_2.5 in classrooms. Weeklong indoor PM_2.5 samples were collected from 32 inner-city schools from a Northeastern U.S. community during three seasons (fall, winter and spring) during the years 2009 to 2013. Concurrently, daily outdoor PM_2.5 samples were taken at a central monitoring site located at a median distance of 4974 m (range 1065-11,592 m) from the schools. Classroom indoor concentrations of PM_2.5 (an average of 5.2 μg/m³) were lower than outdoors (an average of 6.5 μg/m³), and these averages were in the lower range compared to the findings in other schools' studies. The USEPA PMF model was applied to the PM_2.5 components measured simultaneously from classroom indoor and outdoor to estimate the source apportionment. The major sources (contributions) identified across all seasons of indoor PM_2.5 were secondary pollution (41%) and motor vehicles (17%), followed by Calcium (Ca)-rich particles (12%), biomass burning (15%), soil dust (6%), and marine aerosols (4%). Likewise, the major sources of outdoor PM_2.5 across all seasons were secondary pollution (41%) and motor vehicles (26%), followed by biomass burning (17%), soil dust (7%), road dust (3%), and marine aerosols (1%). Secondary pollution was the greatest contributor to indoor and outdoor PM_2.5 over all three seasons, with the highest contribution during spring with 53% to indoor PM_2.5 and 45% to outdoor PM_2.5. Lower contributions of this source during fall and winter are most likely attributed to less infiltration indoors. In contrast, the indoor contribution of motor vehicles source was highest in the fall (29%) and winter (25%), which was presumably categorized by a local source. From the relationship between indoor-to-outdoor sulfur ratios and each source contribution, we also estimated the local and regional influence on indoor PM_2.5 concentration. Overall, the observed differences to indoor PM_2.5 are related to seasonality, and the distinct characteristics and behavior of each classroom/school.

Pediatric Inner-City Asthma

Inner-city children with asthma are known to have high disease mortality and morbidity. Frequently, asthma in this high-risk population is difficult to control and more severe in nature. Several factors, including socioeconomic hardship, ability to access to health care, adherence to medication, exposure to certain allergens, pollution, crowd environment, stress, and infections, play an important role in the pathophysiology of inner-city asthma. Comprehensive control of home allergens and exposure to tobacco smoke, the use of immune based therapies, and school-based asthma programs have shown promising results in asthma control in this population.

Evaluation of MOS social support in low-income caregivers of African American children with poorly controlled asthma

Objective: The purpose of this study was to examine the factor structure of the Medical Outcomes Study Social Support Survey (MOS-SSS) in a sample of low-income, urban caregivers of African American children with poorly controlled asthma. Although the MOS-SSS is a commonly used measure of social support, its psychometric properties have not been studied in this population. Methods: Confirmatory factor analysis was conducted to determine the most appropriate factor structure for the MOS-SSS in caregivers of African American children with frequent Emergency Department visits for uncontrolled asthma. The following models were tested and compared using established fit statistics: an 18-item second-order four factor model, an 18-item four factor model, a bifactor model and an 18-item one factor model with nested models. Results: Participating caregivers were single (75.6%) and female (97%). An 18-item one factor version of the scale had the best fit statistics compared to the other models tested: χ 2 (142) = 308.319, p > 0.001; Root mean square error of approximation (RMSEA) = 0.077; CFI (Comparative Fit Index) = 0.990; and Tucker-Lewis Index (TLI) = 0.988. Construct validity was supported by a statistically significant negative relationship between our final MOS-SSS model and caregiver depressive symptoms ( β = -0.374, p < 0.001). Conclusions: The 18-item one factor MOS-SSS may be appropriate for use in research and clinical practice with caregivers of African American children with poorly controlled asthma. It appears promising as a mechanism to advance understanding of relationships between social support and asthma outcomes in this vulnerable population.

Inner-City Asthma in Children

Asthma in inner-city children is often severe and difficult to control. Residence in poor and urban areas confers increased asthma morbidity even after adjusting for ethnicity, age, and gender. Higher exposure to household pests, such as cockroaches and mice, pollutants and tobacco smoke exposure, poverty, material hardship, poor-quality housing, differences in health care quality, medication compliance, and heath care access also contribute to increased asthma morbidity in this population. Since 1991, the National Institutes of Allergy and Infectious Diseases established research networks: the National Cooperative Inner-City Asthma Study (NCICAS), the Inner-City Asthma Study (ICAS), and the Inner-City Asthma Consortium (ICAC), to improve care for this at risk population. The most striking finding of the NCICAS is the link between asthma morbidity and the high incidence of allergen sensitization and exposure, particularly cockroach. The follow-up ICAS confirmed that reductions in household cockroach and dust mite were associated with reduction in the inner-city asthma morbidity. The ICAC studies have identified that omalizumab lowered fall inner-city asthma exacerbation rate; however, the relationship between inner-city asthma vs immune system dysfunction, respiratory tract infections, prenatal environment, and inner-city environment is still being investigated. Although challenging, certain interventions for inner-city asthma children have shown promising results. These interventions include family-based interventions such as partnering families with asthma-trained social workers, providing guidelines driven asthma care as well as assured access to controller medication, home-based interventions aim at elimination of indoor allergens and tobacco smoke exposure, school-based asthma programs, and computer/web-based asthma programs.

Trends in Racial and Ethnic Disparities in Childhood Asthma in Miami, Florida: 2005-2013

Nationally, racial and ethnic disparities in childhood asthma plateaued from 2005 to 2013. We assessed trends in childhood asthma in Miami, Florida using Youth Risk Behavior Surveillance System (YRBSS) data and emergency department (ED) utilization and hospitalization rates by zip code population characteristics. Asthma prevalence in Miami did not vary significantly by race/ethnicity in YRBSS respondents in 2005 (16.2-17.2%, all groups), but rose in African-Americans and Hispanics and declined in Whites by 2013 to 27.9, 20.9 and 12.6%, respectively (P = 0.02). Median asthma ED visit rates rose from 106.8 (2006-2008) to 138.2 (2011-2013; P = 0.004) per 10,000 children. High-poverty and majority African-American zip codes were 6.3 and 7.3 times more likely to have asthma ED visit rates > 200 than others (P < 0.001). In high-poverty zip codes, majority African-American population was not associated with significantly higher ED utilization. In low-poverty zip codes, the association became stronger. Greater poverty explains much, but not all of Miami African-Americans' higher asthma risk.

Common allergies in urban adolescents and their relationships with asthma control and healthcare utilization

BACKGROUND

Urban adolescents suffer a disproportionate burden of asthma morbidity, often in association with allergies. Literature is limited on comparing various types of allergies regarding prevalence and associations with asthma morbidity in urban dwelling adolescents. The purpose of this study was to examine the prevalence of common allergies reported by urban adolescents and to assess their relationships to healthcare utilization and asthma control.

METHODS

Study participants included 313 urban adolescents (12-20 years of age) with persistent asthma who were recruited from three states in the United States. Self-report data were collected on nine indoor and outdoor allergies, healthcare utilization, and asthma exacerbation. Logistic regressions and zero-inflated Poisson regressions were conducted to examine the relationships between allergies and asthma morbidity.

RESULTS

The mean age of participants was 14.58 (± 1.97) and 52% were female, and 79% were black. Seventy-three percent (n = 229) reported one or more allergies. Dust mite and grass allergies were most common, each reported by 50%. The prevalence of pest allergies (cockroach and mouse) was 27.5% and 19%, respectively. Those with pest allergies were more likely to report ED visits (cockroach- Odds Ratio (OR) = 2.16, 95% CI 1.18-3.94, p = .01; mouse- OR = 2.13, 95% CI 1.09-4.07, p = .02), specialist visits (cockroach-OR = 2.69, 95% CI 1.60-4.54, p < .001; mouse- OR = 2.06, 95% CI 1.15-3.68, p = .01) and asthma exacerbation (cockroach-OR = 2.17, 95% CI 1.26-3.74, p < .001; mouse- OR = 2.30, 95% CI 1.26-4.18, p = .01). Cockroach allergies were associated with 2.2 times as many nights in the hospital (95% CI 1.053-3.398, p = 0.036) and 2.2 times as many specialist visits (95% CI 1.489-3.110, p < 0.001), and mouse allergy was associated with 1.6 times as many ED visits (95% CI 1.092-2.257, p = 0.015) compared to those without pest allergies.

CONCLUSIONS

Concomitant occurrence of allergies is ubiquitous among urban adolescents with asthma. Only pest allergies, of those examined, appear to have implications for poorly controlled asthma, exacerbation and acute healthcare utilization. To reduce asthma burden in urban adolescents, identification and management of high-risk adolescents with pest allergen sensitization and exposure are warranted.

Bedroom Allergen Exposure Beyond House Dust Mites

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Recruitment and retention strategies for an urban adolescent study: Lessons learned from a multi-center study of community-based asthma self-management intervention for adolescents

Intervention studies with urban adolescents and families affected by asthma are critical to improving the disproportionate morbidity in this population. Community-based recruitment and retention strategies in a multi-site longitudinal project evaluating an asthma self-management intervention for adolescents are presented. Successful recruitment strategies depended on the geographic and cultural characteristics of each study site. Partnering with providers and groups known to the target population and in-person contact with target population were found effective. Flexibility accommodating modified and new approaches, securing multiple contacts and repeating mailings as well as capitalizing on the benefits of subject payment was critical to achieving long-term subject engagement of 85% in the study. Ongoing monitoring and adjustment of recruitment and retention strategies is recommended.

Nordic consensus statement on the systematic assessment and management of possible severe asthma in adults

Although a minority of asthma patients suffer from severe asthma, they represent a major clinical challenge in terms of poor symptom control despite high-dose treatment, risk of exacerbations, and side effects. Novel biological treatments may benefit patients with severe asthma, but are expensive, and are only effective in appropriately targeted patients. In some patients, symptoms are driven by other factors than asthma, and all patients with suspected severe asthma ('difficult asthma') should undergo systematic assessment, in order to differentiate between true severe asthma, and 'difficult-to-treat' patients, in whom poor control is related to factors such as poor adherence or co-morbidities. The Nordic Consensus Statement on severe asthma was developed by the Nordic Severe Asthma Network, consisting of members from Norway, Sweden, Finland, Denmark, Iceland and Estonia, including representatives from the respective national respiratory scientific societies with the aim to provide an overview and recommendations regarding the diagnosis, systematic assessment and management of severe asthma. Furthermore, the Consensus Statement proposes recommendations for the organization of severe asthma management in primary, secondary, and tertiary care.

School Environmental Intervention Programs

Exposure to indoor allergens and pollutants plays a significant part in the development of asthma and its associated morbidity. Inner-city children with asthma are disproportionately affected by these exposures with increased asthma morbidity. Although years of previous research have linked exposures in the urban home environment with significant childhood asthma disease, many of these allergens are also present in inner-city school environments. Therefore, evaluation of the school environment of patients with asthma is also essential. School-based environmental interventions may offer benefit for this problem and has the potential to help many children with asthma at once in a cost-effective manner. It is important that environmental health researchers continue to assess which interventions are most practical and result in the greatest measurable improvements.

Macrophage polarization and allergic asthma

Allergic asthma is associated with airway inflammation and airway hyperresponsiveness. Macrophage polarization has been shown to have a profound impact on asthma pathogenesis. On exposure to local microenvironments, recruited macrophages can be polarized into either classically activated (or M1) or alternatively activated (or M2) phenotypes. Macrophage polarization has been heavily associated with development of asthma. The process of regulation of macrophage polarization involves an intricate interplay between various cytokines, chemokines, transcriptional factors, and immune-regulatory cells. Different signals from the microenvironment are controlled by different receptors on the macrophages to initiate various macrophage polarization pathways. Most importantly, there is an increased attention on the epigenetic changes (eg, microRNAs, DNA methylation, and histone modification) that impact macrophage functional responses and M1/M2 polarization through modulating cellular signaling and signature gene expression. Thus, modulation of macrophage phenotypes through molecular intervention by targeting some of those potential macrophage regulators may have therapeutic potential in the treatment of allergic asthma and other allergic diseases. In this review, we will discuss the origin of macrophages, characterization of macrophages, macrophage polarization in asthma, and the underlying mechanisms regarding allergen-induced macrophage polarization with emphasis on the regulation of epigenetics, which will provide new insights into the therapeutic strategy for asthma.

Can we predict fall asthma exacerbations? Validation of the seasonal asthma exacerbation index

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.

Contribution of weight status to asthma prevalence racial disparities, 2-19 year olds, 1988-2014

PURPOSE

Racial disparities in childhood asthma prevalence increased after the 1990s. Obesity, which also varies by race/ethnicity, is an asthma risk factor but its contribution to asthma prevalence disparities is unknown.

METHODS

We analyzed nationally representative National Health Examination and Nutrition Survey data for 2-19 year olds with logistic regression and decomposition analyses to assess the contributions of weight status to racial disparities in asthma prevalence, controlling for sex, age, and income status.

RESULTS

From 1988-1994 to 2011-2014, asthma prevalence increased more among non-Hispanic black (NHB) (8.4% to 18.0%) than non-Hispanic white (NHW) youth (7.2% to 10.3%). Logistic regression showed that obesity was an asthma risk factor for all groups but that a three-way "weight status-race/ethnicity-time" interaction was not significant. That is, weight status did not modify the race/ethnicity association with asthma over time. In decomposition analyses, weight status had a small contribution to NHB/NHW asthma prevalence disparities but most of the disparity remained unexplained by weight status or other asthma risk factors (sex, age and income status).

CONCLUSIONS

NHB youth had a greater asthma prevalence increase from 1988-1994 to 2011-2014 than NHW youth. Most of the racial disparity in asthma prevalence remained unexplained after considering weight status and other characteristics.

New Insights into Cockroach Allergens

PURPOSE OF REVIEW

This review addresses the most recent developments on cockroach allergen research in relation to allergic diseases, especially asthma.

RECENT FINDINGS

The number of allergens relevant to cockroach allergy has recently expanded considerably up to 12 groups. New X-ray crystal structures of allergens from groups 1, 2, and 5 revealed interesting features with implications for allergen standardization, sensitization, diagnosis, and therapy. Cockroach allergy is strongly associated with asthma particularly among children and young adults living in inner-city environments, posing challenges for disease control. Environmental interventions targeted at reducing cockroach allergen exposure have provided conflicting results. Immunotherapy may be a way to modify the natural history of cockroach allergy and decrease symptoms and asthma severity among sensitized and exposed individuals. The new information on cockroach allergens is important for the assessment of allergen markers of exposure and disease, and for the design of immunotherapy trials.

Urban residence, neighborhood poverty, race/ethnicity, and asthma morbidity among children on Medicaid

BACKGROUND

Although poor-urban (inner-city) areas are thought to have high asthma prevalence and morbidity, we recently found that inner cities do not have higher prevalent pediatric asthma. Whether asthma morbidity is higher in inner-city areas across the United States is not known.

OBJECTIVE

This study sought to examine relationships between residence in poor and urban areas, race/ethnicity, and asthma morbidity among children with asthma who are enrolled in Medicaid.

METHODS

Children aged 5 to 19 enrolled in Medicaid in 2009 to 2010 were included. Asthma was defined by at least 1 outpatient or emergency department (ED) visit with a primary diagnosis code of asthma over the 2-year period. Urbanization status was defined at the county level and neighborhood poverty at the zip-code level. Among children with asthma, logistic models were created to examine the effects of urbanization, neighborhood poverty, and race/ethnicity on rates of asthma outpatient visits, ED visits, and hospitalizations.

RESULTS

This study included 16,860,716 children (1,534,820 with asthma). Among children enrolled in Medicaid, residence in inner-city areas did not confer increased risk of prevalent asthma in either crude or adjusted analyses, but it was associated with significantly more asthma-related ED visits and hospitalizations among those with asthma in crude analyses (risk ratio, 1.48; 95% CI, 1.24-1.36; and 1.97; 95% CI, 1.50-1.72, respectively) and when adjusted for race/ethnicity, age, and sex (adjusted risk ratio, 1.23; 95% CI, 1.08-1.15; and 1.62; 95% CI, 1.26-1.43). Residence in urban or poor areas and non-Hispanic black race/ethnicity were all independently associated with increased risk of asthma-related ED visits and hospitalizations.

CONCLUSIONS

Residence in poor and urban areas is an important risk factor for asthma morbidity, but not for prevalence, among low-income US children.

Effect of aging on sputum inflammation and asthma control

BACKGROUND

Aged asthmatic patients experience increased morbidity and mortality. Knowledge of the aging effect on airway inflammation and asthma control is limited.

OBJECTIVE

We sought to compare airway inflammation and its relationship to asthma control in aged versus younger patients and determine whether differences are asthma specific or caused by "inflamm-aging."

METHODS

We performed a prospective study of aged (>60 years) and younger (21-40 years) inner-city patients with asthma. After a run-in period to control for inhaled corticosteroid use, induced sputum was collected. Age-matched nonasthmatic control subjects were included to measure age-related inflammatory changes.

RESULTS

Aged (mean age, 67.9 ± 5.1 years; n = 35) compared with younger (mean age, 30.8 ± 5.9 years; n = 37) asthmatic patients had significantly worse asthma control and lower FEV₁. Aged asthmatic patients had higher sputum neutrophil (30.5 × 10⁴/mL and 23.1%) and eosinophil (7.0 × 10⁴/mL and 3.8%) numbers and percentages compared with younger patients (neutrophils, 13.0 × 10⁴/mL [P < .01] and 6.9% [P < .01]; eosinophils, 2.0 × 10⁴/mL [P < .01] and 1.2% [P < .01]). Aged asthmatic patients had higher sputum IL-6 (P < .01) and IL-8 (P = .01) levels. No significant inflammatory differences between aged and younger control subjects were observed. In aged asthmatic patients increased sputum IL-6 and macrophage inflammatory protein 3α/CCL20 levels were significantly associated with decreased asthma control and increased sputum neutrophil numbers and IL-1β, IL-6, and macrophage inflammatory protein 3α/CCL20 levels were associated with hospitalization.

CONCLUSIONS

The inflammatory patterns of aged versus younger asthmatic patients are associated with increased sputum neutrophil and eosinophil values and cytokine levels related to neutrophil recruitment. Differences in airway inflammation can contribute to diminished asthma control in the aged. Further understanding of asthma pathophysiology in aged patients is needed to improve management of this vulnerable population.

Cockroach allergen exposure and risk of asthma

Cockroach sensitization is an important risk factor for the development of asthma. However, its underlying immune mechanisms and the genetic etiology for differences in allergic responses remain unclear. Cockroach allergens identification and their expression as biologically active recombinant proteins have provided a basis for studying the mechanisms regarding cockroach allergen-induced allergic sensitization and asthma. Glycans in allergens may play a crucial role in the immunogenicity of allergic diseases. Protease-activated receptor (PAR)-2, Toll-like receptor (TLR), and C-type lectin receptors have been suggested to be important for the penetration of cockroach allergens through epithelial cells to mediate allergen uptake, dendritic cell maturation, antigen-presenting cell (APC) function in T-cell polarization, and cytokine production. Environmental pollutants, which often coexist with the allergen, could synergistically elicit allergic inflammation, and aryl hydrocarbon receptor (AhR) activation and signaling may serve as a link between these two elements. Genetic factors may also play an important role in conferring the susceptibility to cockroach sensitization. Several genes have been associated with cockroach sensitization and asthma-related phenotypes. In this review, we will discuss the epidemiological evidence for cockroach allergen-induced asthma, cockroach allergens, the mechanisms regarding cockroach allergen-induced innate immune responses, and the genetic basis for cockroach sensitization.

Individualized Household Allergen Intervention Lowers Allergen Level But Not Asthma Medication Use: A Randomized Controlled Trial

BACKGROUND

Environmental exposures to indoor allergens are major contributors to asthma symptoms, particularly in inner cities. The effectiveness of household allergen reduction as an adjunct to National Asthma Education Prevention Program guideline-based pharmacologic therapy in asthma has not been prospectively studied.

OBJECTIVE

To study the effect of individualized allergen reduction on ability to reduce asthma pharmacologic therapy over 40 weeks.

METHODS

We performed a randomized controlled trial to determine the effect of multifaceted indoor allergen avoidance measures on the ability to reduce asthma controller therapy in adults and children residing in New York City who were both sensitized and exposed to at least 1 indoor allergen. Asthma treatment and control were optimized in all subjects before randomization.

RESULTS

A total of 125 subjects were randomized to receive individualized household allergen reduction and 122 received a sham intervention. Subjects in the intervention group significantly reduced all measured allergen levels (cat, dog, dust mite allergens in the bedroom, cockroach and mouse allergens in the kitchen and bedroom); those in the control group reduced only dust mite and mouse allergens in the bedroom and cockroach allergen in the kitchen. Participants in the intervention arm reduced National Asthma Education Prevention Program-based therapy from step 4.4 at randomization to 3.50 postintervention (range, 0-6); participants in the control arm reduced medication from step 4.4 to 3.4 (P = .76). There were no differences in other measured asthma outcomes.

CONCLUSIONS

Targeted allergen avoidance measures do not allow for reduction in asthma pharmacologic therapy compared with usual care in patients already receiving optimal controller therapy.

Influence of ethnicity on response to asthma drugs

INTRODUCTION

Understanding variability in the response to asthma medications is essential to ensure appropriate prescribing. Given that there are increased asthma treatment failures observed in ethnic minorities receiving asthma therapeutics, it is fundamental to understand the factors related to ethnicity that can modify the response to asthma therapy.

AREAS COVERED

Race/ethnicity is an important determinant of drug response and therefore contributes to interindividual variability. It is generally recognized that its effects on drug response are determined by both genetic and environmental factors to a varying extent, depending on the ethnic groups and probe drugs studied. Also, adherence to therapy can influence pharmacological response to asthma therapeutics.

EXPERT OPINION

Health-care professionals might never use the treatment in their patients irrespective of their ethnicity and thus inadvertently increase ethnic health inequality. However, our understanding of whether and/or how ethnicity influences pharmacological response to asthma therapeutics is still very scarce. A holistic, integrative systems biology approach that combines large-scale molecular profiling traits (e.g., transcriptomic, proteomic, metabolomic traits) and genetic variants could help to personalize the treatment of asthmatic patients regardless of race/ethnicity.