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Background: Asthma is the most common chronic lung disease of childhood, affecting approximately 6 million children in the United States. Although asthma cannot be cured, most of the time, asthma symptoms can be controlled by avoiding or reducing exposure to asthma triggers (allergens and irritants) and by following recommendations for asthma education and appropriate medical care., Methods: CDC analyzed asthma data from the 2001-2016 National Health Interview Survey for children aged 0-17 years to examine trends and demographic differences in health outcomes and health care use., Results: Asthma was more prevalent among boys (9.2%) than among girls (7.4%), children aged ≥5 years (approximately 10%) than children aged <5 years (3.8%), non-Hispanic black (black) children (15.7%) and children of Puerto Rican descent (12.9%) than among non-Hispanic white (white) children (7.1%), and children living in low income families (10.5%) than among those living in families with income ≥250% of the Federal Poverty Level (FPL) (approximately 7%). Asthma prevalence among children increased from 8.7% in 2001 to 9.4% in 2010, and then decreased to 8.3% in 2016. Although not all changes were statistically significant, a similar pattern was observed among subdemographic groups studied, with the exception of Mexican/Mexican-American children, among whom asthma prevalence increased from 5.1% in 2001 to 6.5% in 2016. Among children with asthma, the percentage who had an asthma attack in the past 12 months declined significantly from 2001 to 2016. Whereas asthma prevalence was lower among children aged 0-4 years than among older children, the prevalence of asthma attacks (62.4%), emergency department or urgent care center (ED/UC) visits (31.1%), and hospitalization (10.4%) were higher among children with asthma aged 0-4 years than among those aged 12-17 years (44.8%, 9.6%, and 2.8%, respectively). During 2013, children with asthma aged 5-17 years missed 13.8 million days of school per year (2.6 days per child). Compared with 2003, in 2013, the prevalence of adverse health outcomes and health care use were significantly lower and the prevalence of having an action plan to manage asthma was higher., Conclusions and Implications for Public Health Practice: Asthma remains an important public health and medical problem. The health of children with asthma can be improved by promoting asthma control strategies, including asthma trigger reduction, appropriate guidelines-based medical management, and asthma education for children, parents, and others involved in asthma care., Competing Interests: No conflicts of interest were reported.

Background: Broccoli sprouts (BS) are the richest source of sulforaphane (SFN), which is a potent inducer of phase II enzymes, which play a critical role in preventing oxidative stress (OS) and inflammation., Objectives: The objective of this study was to determine if ingestion of whole BS improves airway inflammatory and physiologic outcomes, and OS in adults with asthma and allergic sensitization to an indoor allergen., Methods: The study is a double-blind, placebo-controlled, randomized trial to compare the effects of BS with placebo (alfalfa sprouts [AS]) on airway inflammation and markers of OS. Forty adults (aged 18-50 years) were randomized to eat either (a) 100 g of BS daily or (b) 100 g of AS daily for 3 days. Fractional exhaled nitric oxide (FENO), forced expiratory volume 1, nasal epithelial and PBMC gene expression, inflammatory and OS biomarkers, and symptoms were assessed both before and after ingestion of the sprouts. The primary outcome variable was the change in FENO. Secondary outcome measures included rhinitis and asthma symptoms, lung function, and OS and inflammatory biomarkers., Results: BS ingestion for 3 consecutive days did not reduce FENO, despite resulting in a marked increase in serum SFN concentrations (21 vs 22 parts per billion, P = .76). Furthermore, BS consumption did not induce cytoprotective antioxidant genes in either PBMCs or nasal epithelial cells, reduce OS and inflammatory markers, or improve lung function., Conclusions: Ingestion of whole BS for 3 days does not appear to improve eosinophilic pulmonary inflammation, inflammatory and OS biomarkers, or clinical features of asthma among atopic adults with asthma despite resulting in a marked increase in serum SFN levels., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Purpose: Adherence to a Mediterranean diet pattern may be associated with lower asthma prevalence in children. We sought to corroborate these findings in Peruvian children., Methods: This case-control study included children of ages 9-19 years living in Lima, Peru. A food frequency questionnaire (FFQ) was completed and diet pattern was analyzed using a modified Mediterranean diet score (MDS). Primary analysis investigated the relationship between MDS and asthma status. Maternal education, age, sex, and body mass index category were included in multivariate model. Secondary outcomes included asthma control, forced expiratory volume in 1 s (FEV1), allergic rhinitis, and atopic status., Results: 287 participants with asthma and 96 controls without asthma completed a FFQ. Mean age was 13.5 years. According to the asthma control test (ACT), 86 % of those with asthma were controlled (score >19). MDS scores ranged 6-18 (median 15). In adjusted analysis, being above the median MDS scores was associated with decreased odds of asthma [OR = 0.55, 95 % CI (0.33, 0.92), p = 0.02]. Among children whose mothers completed secondary education, being above the median MDS significantly decreased the odds of asthma [OR = 0.31, 95 % CI (0.14, 0.71), p < 0.01], whereas among those whose mothers did not complete secondary education there was no protective effect [OR = 0.86, 95 % CI (0.43, 1.7), p = 0.66]. There was no association between MDS scores and asthma control, FEV1, allergic rhinitis, or atopic status., Conclusion: Adherence to the Mediterranean diet was inversely associated with having asthma among children in Lima, Peru. This effect was strongest among children with better educated mothers.

Asthma development and pathogenesis are influenced by the interactions of airway epithelial cells and innate and adaptive immune cells in response to allergens. Oxidative stress is an important mediator of asthmatic phenotypes in these cell types. Nuclear erythroid 2-related factor 2 (Nrf2) is a redox-sensitive transcription factor that is the key regulator of the response to oxidative and environmental stress. We previously demonstrated that Nrf2-deficient mice have heightened susceptibility to asthma, including elevated oxidative stress, inflammation, mucus, and airway hyperresponsiveness (AHR) (Rangasamy T, Guo J, Mitzner WA, Roman J, Singh A, Fryer AD, Yamamoto M, Kensler TW, Tuder RM, Georas SN, Biswal S. J Exp Med 202: 47-59, 2005). Here we dissected the role of Nrf2 in lung epithelial cells and tested whether genetic or pharmacological activation of Nrf2 reduces allergic asthma in mice. Cell-specific activation of Nrf2 in club cells of the airway epithelium significantly reduced allergen-induced AHR, inflammation, mucus, Th2 cytokine secretion, oxidative stress, and airway leakiness and increased airway levels of tight junction proteins zonula occludens-1 and E-cadherin. In isolated airway epithelial cells, Nrf2 enhanced epithelial barrier function and increased localization of zonula occludens-1 to the cell surface. Pharmacological activation of Nrf2 by 2-trifluoromethyl-2'-methoxychalone during the allergen challenge was sufficient to reduce allergic inflammation and AHR. New therapeutic options are needed for asthma, and this study demonstrates that activation of Nrf2 in lung epithelial cells is a novel potential therapeutic target to reduce asthma susceptibility., (Copyright © 2015 the American Physiological Society.)

Objective: Radical changes in diet have paralleled the increase in asthma with shifts toward a "Western" diet pattern, characterized by the high intake of processed meats and refined grains, high-fat dairy products, and sugary desserts and drinks. Because diet represents a modifiable risk factor in numerous chronic diseases, the authors examined the association between consumption of a Western diet pattern and asthma incidence, prevalence, and morbidity in adults., Data Sources: PubMed, Cochrane, Web of Science, and Scopus were searched for peer-reviewed publications published from January 1980 to April 2014., Study Selection: Studies retrieved for inclusion assessed dietary patterns representative of a Western diet and asthma incidence, prevalence, respiratory symptoms, and lung function., Results: Ten observational studies conducted in North American, European, and Asian countries, ranging from 153 to more than 70,000 individuals, did not provide evidence to support an association between a Western dietary pattern and asthma incidence and prevalence. Five of these studies also investigated asthma morbidity, with variable findings., Conclusion: Current evidence does not support an association between a Western diet and incident or prevalent adult asthma but does suggest a possible link between a Western diet pattern and adult asthma morbidity., (Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Previous research has found evidence of an association between indoor air pollution and asthma morbidity in children. Environmental intervention studies have been performed to examine the role of household environmental interventions in altering indoor air pollution concentrations and improving health. Previous environmental intervention studies have found only modest effects on health outcomes and it is unclear if the health benefits provided by environmental modification are comparable with those provided by medication. Traditionally, the statistical analysis of environmental intervention studies has involved performing two intention-to-treat analyses that separately estimate the effect of the environmental intervention on health and the effect of the environmental intervention on indoor air pollution concentrations. We propose a principal stratification approach to examine the extent to which an environmental intervention's effect on health outcomes coincides with its effect on indoor air pollution. We apply this approach to data from a randomized air cleaner intervention trial conducted in a population of asthmatic children living in Baltimore, Maryland, USA. We find that among children for whom the air cleaner reduced indoor particulate matter concentrations, the intervention resulted in a meaningful improvement of asthma symptoms with an effect generally larger than previous studies have shown. A key benefit of using principal stratification in environmental intervention studies is that it allows investigators to estimate causal effects of the intervention for sub-groups defined by changes in the indoor air pollution concentration., (Copyright © 2014 John Wiley & Sons, Ltd.)

Rationale: The effect of endotoxin on asthma morbidity in urban populations is unclear., Objectives: To determine if indoor pollutant exposure modifies the relationships between indoor airborne endotoxin and asthma health and morbidity., Methods: One hundred forty-six children and adolescents with persistent asthma underwent repeated clinical assessments at 0, 3, 6, 9, and 12 months. Home visits were conducted at the same time points for assessment of airborne nicotine, endotoxin, and nitrogen dioxide (NO2) concentrations. The effect of concomitant pollutant exposure on relationships between endotoxin and asthma outcomes were examined in stratified analyses and statistical models with interaction terms., Measurements and Main Results: Both air nicotine and NO2 concentrations modified the relationships between airborne endotoxin and asthma outcomes. Among children living in homes with no detectable air nicotine, higher endotoxin was inversely associated with acute visits and oral corticosteroid bursts, whereas among those in homes with detectable air nicotine, endotoxin was positively associated with these outcomes (interaction P value = 0.004 and 0.07, respectively). Among children living in homes with lower NO2 concentrations (<20 ppb), higher endotoxin was positively associated with acute visits, whereas among those living in homes with higher NO2 concentrations, endotoxin was negatively associated with acute visit (interaction P value = 0.05). NO2 also modified the effect of endotoxin on asthma symptom outcomes in a similar manner., Conclusions: The effects of household airborne endotoxin exposure on asthma are modified by coexposure to air nicotine and NO2, and these pollutants have opposite effects on the relationships between endotoxin and asthma-related outcomes.

Background: Cockroach and mouse allergens have both been implicated as causes in inner-city asthma morbidity in multicenter studies, but whether both allergens are clinically relevant within specific inner-city communities is unclear., Objective: Our study aimed to identify relevant allergens in Baltimore City., Methods: One hundred forty-four children (5-17 years old) with asthma underwent skin prick tests at baseline and had clinical data collected at baseline and 3, 6, 9, and 12 months. Home settled dust samples were collected at the same time points for quantification of indoor allergens. Participants were grouped based on their sensitization and exposure status to each allergen. All analyses were adjusted for age, sex, and serum total IgE level., Results: Forty-one percent were mouse sensitized/exposed, and 41% were cockroach sensitized/exposed based on bedroom floor exposure data. Mouse sensitization/exposure was associated with acute care visits, decreased FEV1/forced vital capacity percentage values, fraction of exhaled nitric oxide levels, and bronchodilator reversibility. Cockroach sensitization/exposure was only associated with acute care visits and bronchodilator reversibility when exposure was defined by using bedroom floor allergen levels. Mouse-specific IgE levels were associated with poor asthma health across a range of outcomes, whereas cockroach-specific IgE levels were not. The relationships between asthma outcomes and mouse allergen were independent of cockroach allergen. Although sensitization/exposure to both mouse and cockroach was generally associated with worse asthma, mouse sensitization/exposure was the primary contributor to these relationships., Conclusions: In a community with high levels of both mouse and cockroach allergens, mouse allergen appears to be more strongly and consistently associated with poor asthma outcomes than cockroach allergen. Community-level asthma interventions in Baltimore should prioritize reducing mouse allergen exposure., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: American Thoracic Society guidelines support using fractional exhaled nitric oxide (FENO) measurements in patients with asthma and highlight gaps in the evidence base. Little is known about the use of FENO levels to predict asthma exacerbations among high-risk, urban, minority populations receiving usual care., Methods: Children with persistent asthma (n = 138) were enrolled in a prospective, observational cohort study and skin tested at baseline (a wheal ≥ 3 mm indicated a positive skin-prick test). FENO levels, lung function, and asthma-related health-care use were assessed at baseline and every 3 months thereafter for 1 year. Relationships between FENO levels and health-care use in the subsequent 3 months were examined. Final models accounted for repeated outcome measures and were adjusted for age, sex, and lung function., Results: The mean age of the children was 11 years (range, 5-17 years), and most were male (57%), black (91%), and atopic (90%). At baseline, the median FENO level was 31.5 parts per billion (interquartile range, 16-61 ppb) and mean FEV1/FVC was 80.7% (SD, ± 9.6%). There were 237 acute asthma-related health-care visits, 105 unscheduled doctor visits, 125 ED visits, and seven hospitalizations during the follow-up period. FENO level was not a significant predictor of acute visits, ED visits, unscheduled doctor visits, or hospitalization in either unadjusted or adjusted analyses. Use of recommended cut points did not improve the predictive value of the FENO level (positive predictive value, 0.6%-32.8%) nor did application of the guideline-based algorithm to assess change over time., Conclusions: FENO level may not be a clinically useful predictor of health-care use for asthma exacerbations in urban minority children with asthma.

Home mouse allergen exposure is associated with asthma morbidity, but little is known about the shape of the dose-response relationship or the relevance of location of exposure within the home. Asthma outcome and allergen exposure data were collected every 3 months for 1 year in 150 urban children with asthma. Participants were stratified by mouse sensitization, and relationships between continuous measures of mouse allergen exposure and outcomes of interest were analyzed. Every tenfold increase in the bed mouse allergen level was associated with an 87% increase in the odds of any asthma-related health care use among mouse-sensitized [Odds Ratio (95% CI): 1.87 (1.21-2.88)], but not non-mouse-sensitized participants. Similar relationships were observed for emergency department visit and unscheduled doctor visit among mouse-sensitized participants. Kitchen floor and bedroom air mouse allergen concentrations were also associated with greater odds of asthma-related healthcare utilization; however, the magnitude of the association was less than that observed for bed mouse allergen concentrations. In this population of urban children with asthma, there is a linear dose-response relationship between mouse allergen concentrations and asthma morbidity among mouse-sensitized asthmatics. Bed and bedroom air mouse allergen exposure compartments may have a greater impact on asthma morbidity than other compartments., (© 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: The inner-city pediatric population in the United States has a disproportionate burden of asthma. Recent attention has focused on the immunomodulatory role of vitamin D, which may be protective against disease morbidity. As the primary determinant of vitamin D status in humans is exposure to sunlight, we aimed to determine if 25-OH vitamin D levels in urban preschool children with asthma were low, influenced by time spent outdoors, and associated with asthma morbidity., Methods: Serum 25-OH vitamin D levels were measured at baseline in a cohort of 121 inner-city children ages 2-6 years with asthma in Baltimore, MD. Participants were followed longitudinally at 3 and 6 months to assess time spent outdoors, asthma symptoms through questionnaires and daily diaries, and allergic markers., Results: In a predominantly black population of preschool children, the median 25-OH vitamin D level was 28 ng/mL (IQR 21.2-36.9), with 54% of the children below the traditionally sufficient level of 30 ng/mL and 7.4% in the range associated with risk of rickets (< 15 ng/mL). The median time spent outdoors was 3 hours/day (IQR 2-4), and greater time spent outdoors was not associated with higher vitamin D levels. 25-OH vitamin D did not show seasonal variation in our cohort (p = 0.66). Lower 25-OH levels were correlated with higher IgE levels., Conclusions: Urban African-American preschool children with asthma have high rates of vitamin D insufficiency, and increased outdoor exposure is unlikely to correct these low 25-OH vitamin D levels. Repletion in this population may require dietary supplementation.

Background: Both being overweight and exposure to indoor pollutants, which have been associated with worse health of asthmatic patients, are common in urban minority populations. Whether being overweight is a risk factor for the effects of indoor pollutant exposure on asthma health is unknown., Objectives: We sought to examine the effect of weight on the relationship between indoor pollutant exposure and asthma health in urban minority children., Methods: One hundred forty-eight children (age, 5-17 years) with persistent asthma were followed for 1 year. Asthma symptoms, health care use, lung function, pulmonary inflammation, and indoor pollutants were assessed every 3 months. Weight category was based on body mass index percentile., Results: Participants were predominantly African American (91%) and had public health insurance (85%). Four percent were underweight, 52% were normal weight, 16% were overweight, and 28% were obese. Overweight or obese participants had more symptoms associated with exposure to fine particulate matter measuring less than 2.5 μm in diameter (PM2.5) than normal-weight participants across a range of asthma symptoms. Overweight or obese participants also had more asthma symptoms associated with nitrogen dioxide (NO2) exposure than normal-weight participants, although this was not observed across all types of asthma symptoms. Weight did not affect the relationship between exposure to coarse particulate matter measuring between 2.5 and 10 μm in diameter and asthma symptoms. Relationships between indoor pollutant exposure and health care use, lung function, or pulmonary inflammation did not differ by weight., Conclusion: Being overweight or obese can increase susceptibility to indoor PM2.5 and NO2 in urban children with asthma. Interventions aimed at weight loss might reduce asthma symptom responses to PM2.5 and NO2, and interventions aimed at reducing indoor pollutant levels might be particularly beneficial in overweight children., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: Asthma is a growing public health problem in developing countries. However, few studies have studied the role of urbanisation in this phenomenon. It was hypothesised that children living in a peri-urban setting in Peru have higher rates of asthma and allergy than rural counterparts., Methods: 1441 adolescents aged 13-15 years were enrolled from two settings: a peri-urban shanty town in Lima (n = 725) and 23 rural villages in Tumbes (n = 716). Participants filled in questionnaires on asthma and allergy symptoms, environmental exposures and sociodemographics, and underwent spirometry, and exhaled nitric oxide (eNO) and allergy skin testing. Indoor particulate matter (PM) concentrations were measured in 170 households., Results: Lima adolescents had higher rates of lifetime wheezing (22% vs 10%), current asthma symptoms (12% vs 3%) and physician-diagnosed asthma (13% vs 2%; all p <0.001). Current rhinitis (23% vs 12%), eczema (12% vs 0.4%), atopy (56% vs 38%), personal history of cigarette smoking (7.4% vs 1.3%) and mean indoor PM (31 vs 13 μg/m(3)) were also higher in Lima (all p < 0.001). The peri-urban environment of Lima was associated with a 2.6-fold greater odds (95% CI 1.3 to 5.3) of asthma in multivariable regression. Forced expiratory volumes were higher and FEV(1)/FVC (forced expiratory volume in 1 s/forced vital capacity) ratios were lower in Lima (all p < 0.001). Higher eNO values in Lima (p < 0.001) were attributable to higher rates of asthma and atopy., Conclusions: Peri-urban adolescents had more asthma, atopy and airways inflammation and were exposed to more indoor pollution. The findings provide evidence of the risks posed to lung health by peri-urban environments in developing countries.

Background and Aims: Children living in the inner city are particularly vulnerable to asthma. While we know much about factors that affect near-term outcomes in inner-city children, there is little evidence to guide clinicians on what to expect in the coming years, especially in preschool children. The purpose of our study was to determine which clinical and environmental factors are predictive of poor long-term asthma control in preschool inner-city children., Materials and Methods: Baseline characteristics determined to be potential predictors of asthma severity were examined: demographics, asthma symptoms, medication use, healthcare utilization, early life medical history, family history, allergen exposure and allergic disease, and pollutant exposure. Bivariate and multivariate analyses were performed using logistic regression to examine the association of predictors of asthma severity with healthcare utilization at 2 years., Results: Of the 150 children at baseline, the follow-up rate was 83% at 2 years; therefore, 124 children were included in final analyses. At baseline, the mean age was 4.4 years and participants were predominantly African-American (90%). Most of the children were atopic and 32.5% reported using inhaled corticosteroids. Nighttime awakening from asthma and a history of pneumonia were predictive of future poor control., Conclusion: Preschool children with nighttime awakening from asthma and a history of pneumonia may deserve closer monitoring to prevent future asthma morbidity.

Background: Compared with atopic asthma, fewer environmental modifications are recommended for non-atopic asthma in children., Objective: To better understand the role of indoor pollutants in provoking non-atopic asthma, we investigated the effect of in-home particulate matter on asthma symptoms among non-atopic and atopic children living in inner-city Baltimore., Methods: A cohort of 150 children ages 2 to 6 years with asthma underwent home environmental monitoring for 3-day intervals at baseline, 3, and 6 months. Children were classified as non-atopic if they were skin test negative to a panel of 14 aeroallergens. Caregivers completed questionnaires assessing symptoms and rescue medication use. Longitudinal data analysis included regression models with generalized estimating equations., Results: Children were primarily African American from lower socioeconomic backgrounds and spent most of their time in the home. Thirty-one percent were non-atopic, and 69% were atopic. Among non-atopic and atopic children, increased in-home fine (PM2.5) and coarse (PM2.5-10) particle concentrations were associated with significant increases in asthma symptoms and rescue medication use ranging from 7% (95% confidence interval [CI], 0-15) to 14% (95% CI, 1-27) per 10 μg/m(3) increase in particle concentration after adjustment for confounders., Conclusions: In-home particles similarly cause increased symptoms of asthma in non-atopic and atopic children. Environmental control strategies that reduce particle concentrations may prove to be an effective means of improving asthma outcomes, especially for non-atopic asthma, for which there are few environmental control practice recommendations., (Copyright © 2011. Published by Elsevier Inc.)

Background: Proximity to roadways increases the risk of asthma in developed countries; however, relatively little is known about this relationship in developing countries, where rapid and uncontrolled growth of cities has resulted in urban sprawl and heavy traffic volumes., Objective: We sought to determine the effect of distance from a heavily transited avenue on asthma symptoms and quantitative respiratory outcome measures in a periurban shantytown in Lima, Peru., Methods: We enrolled 725 adolescents aged 13 to 15 years who were administered a survey on asthma symptoms and measured spirometry, response to allergy skin testing, and exhaled nitric oxide (eNO). We calculated distances from the main avenue for all households and measured indoor particulate matter in 100 households. We used multivariable regression to model the risk of asthma symptoms, risk of atopy, eNO levels, and FEV(1)/forced vital capacity ratio as a function of distance., Results: Compared against 384 meters, the odds of current asthma symptoms in households living within 100 meters increased by a factor of 2 (P < .05). The odds of atopy increased by a factor of 1.07 for every 100-meter difference in the distance from the avenue (P = .03). We found an inverse relationship in prebronchodilator FEV(1)/forced vital capacity and distance to the avenue in female subjects (P = .01) but not in male subjects. We did not find an association between eNO or household particulate matter levels and distance., Conclusion: Living in close proximity to a high-traffic-density avenue in a periurban community in Peru was associated with a greater risk of asthma symptoms and atopy. Regulation of mobile-source pollutants in periurban areas of developing countries might help reduce the burden of asthma symptoms and atopy., (Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

The purpose of this article is to review indoor air pollution factors that can modify asthma severity, particularly in inner-city environments. While there is a large literature linking ambient air pollution and asthma morbidity, less is known about the impact of indoor air pollution on asthma. Concentrating on the indoor environments is particularly important for children, since they can spend as much as 90% of their time indoors. This review focuses on studies conducted by the Johns Hopkins Center for Childhood Asthma in the Urban Environment as well as other relevant epidemiologic studies. Analysis of exposure outcome relationships in the published literature demonstrates the importance of evaluating indoor home environmental air pollution sources as risk factors for asthma morbidity. Important indoor air pollution determinants of asthma morbidity in urban environments include particulate matter (particularly the coarse fraction), nitrogen dioxide, and airborne mouse allergen exposure. Avoidance of harmful environmental exposures is a key component of national and international guideline recommendations for management of asthma. This literature suggests that modifying the indoor environment to reduce particulate matter, NO(2), and mouse allergen may be an important asthma management strategy. More research documenting effectiveness of interventions to reduce those exposures and improve asthma outcomes is needed.

Background: Although outdoor particulate matter (PM) has been linked to mortality and asthma morbidity, the impact of indoor PM on asthma has not been well established., Objective: This study was designed to investigate the effect of in-home PM on asthma morbidity., Methods: For a cohort of 150 asthmatic children (2-6 years of age) from Baltimore, Maryland, a technician deployed environmental monitoring equipment in the children's bedrooms for 3-day intervals at baseline and at 3 and 6 months. Caregivers completed questionnaires and daily diaries during air sampling. Longitudinal data analyses included regression models with generalized estimating equations., Results: Children were primarily African Americans (91%) from lower socioeconomic backgrounds and spent most of their time in the home. Mean (+/- SD) indoor PM(2.5-10) (PM with aerodynamic diameter 2.5-10 microm) and PM(2.5) (aerodynamic diameter < 2.5 microm) concentrations were 17.4 +/- 21.0 and 40.3 +/- 35.4 microg/m(3). In adjusted models, 10-microg/m(3) increases in indoor PM(2.5-10) and PM(2.5) were associated with increased incidences of asthma symptoms: 6% [95% confidence interval (CI), 1 to 12%] and 3% (95% CI, -1 to 7%), respectively; symptoms causing children to slow down: 8% (95% CI, 2 to 14%) and 4% (95% CI, 0 to 9%), respectively; nocturnal symptoms: 8% (95% CI, 1 to 14%) and 6% (95% CI, 1 to 10%), respectively; wheezing that limited speech: 11% (95% CI, 3 to 19%) and 7% (95% CI, 0 to 14%), respectively; and use of rescue medication: 6% (95% CI, 1 to 10%) and 4% (95% CI, 1 to 8%), respectively. Increases of 10 microg/m(3) in indoor and ambient PM(2.5) were associated with 7% (95% CI, 2 to 11%) and 26% (95% CI, 1 to 52%) increases in exercise-related symptoms, respectively., Conclusions: Among preschool asthmatic children in Baltimore, increases in in-home PM(2.5-10) and PM(2.5) were associated with respiratory symptoms and rescue medication use. Increases in in-home and ambient PM(2.5) were associated with exercise-related symptoms. Although reducing PM outdoors may decrease asthma morbidity, reducing PM indoors, especially in homes of inner-city children, may lead to improved asthma health.

Background: The effect of indoor nitrogen dioxide concentrations on asthma morbidity among inner-city preschool children is uncertain., Objectives: Our goal was to estimate the effect of indoor NO2 concentrations on asthma morbidity in an inner-city population while adjusting for other indoor pollutants., Methods: We recruited 150 children (2-6 years of age) with physician-diagnosed asthma from inner-city Baltimore, Maryland. Indoor air was monitored over a 72-hr period in the children's bedrooms at baseline and 3 and 6 months. At each visit, the child's caregiver completed a questionnaire assessing asthma symptoms over the previous 2 weeks and recent health care utilization., Results: Children were 58% male, 91% African American, and 42% from households with annual income < $25,000; 63% had persistent asthma symptoms. The mean (+/- SD) in-home NO2 concentration was 30.0 +/- 33.7 (range, 2.9-394.0) ppb. The presence of a gas stove and the use of a space heater or oven/stove for heat were independently associated with higher NO2 concentrations. Each 20-ppb increase in NO2 exposure was associated significantly with an increase in the number of days with limited speech [incidence rate ratio (IRR) = 1.15; 95% confidence interval (CI), 1.05-1.25], cough (IRR = 1.10; 95% CI, 1.02-1.18), and nocturnal symptoms (IRR = 1.09; 95% CI, 1.02-1.16), after adjustment for potential confounders. NO2 concentrations were not associated with increased health care utilization., Conclusions: Higher indoor NO2 concentrations were associated with increased asthma symptoms in preschool inner-city children. Interventions aimed at lowering NO2 concentrations in inner-city homes may reduce asthma morbidity in this vulnerable population.

Inner-city residents continue to suffer disproportionate asthma morbidity despite recent progress in reducing asthma morbidity and mortality in other strata of the United States population. Studies over the past decade indicate that the indoor environment is a strong contributor to poor asthma control and asthma-related health care use in inner-city populations. Certain indoor exposures are more common and occur in higher concentrations in inner-city communities than in suburban communities. Identification of "asthmagenic" indoor exposures has paved the way for the development of intervention strategies aimed at reducing asthma morbidity. This article reviews the growing body of evidence that certain indoor environmental exposures contribute to the burden of asthma in the inner city.

Prior studies have related community violence to depression among children, but few studies have examined this relationship among adults. We hypothesized that victimization, awareness, and fear of neighborhood violence would increase the odds of depression among adult caregivers of children with asthma. We surveyed caregivers in the Baltimore Indoor Environment Study of Asthma in Kids (BIESAK), USA. The primary outcome was screening positive for depression on the Center for Epidemiological Studies Depression index. We assessed victimization, awareness, and fear of neighborhood violence, and conducted spatial analysis identifying subject homes within 500 ft of a homicide to validate survey measures of neighborhood violence. A multilevel logistic model with clustering by neighborhood estimated odds ratios and 95% confidence intervals. Survey responses about fear of neighborhood violence were strongly predicted by having a home within 500 ft of a homicide. Of 150 caregivers of children with asthma, 49% were aware of a neighborhood violent event, 36% were fearful of neighborhood violence, 22% reported victimization, and 27% had a homicide within 500 ft of the home. In our multilevel model, fear of violence increased the odds of depression by 6.7. Victimization was associated with a possible trend towards depression, and awareness of neighborhood violence did not increase the odds of depression. Based on our findings, personal experience with neighborhood violence may be more important than simple awareness. Health care workers should consider screening for depression among patients exposed to community violence.

Management of asthma requires attention to environmental exposures both indoors and outdoors. Americans spend most of their time indoors, where they have a greater ability to modify their environment. The indoor environment contains both pollutants (eg, particulate matter, nitrogen dioxide, secondhand smoke, and ozone) and allergens from furred pets, dust mites, cockroaches, rodents, and molds. Indoor particulate matter consists of particles generated from indoor sources such as cooking and cleaning activities, and particles that penetrate from the outdoors. Nitrogen dioxide sources include gas stoves, furnaces, and fireplaces. Indoor particulate matter and nitrogen dioxide are linked to asthma morbidity. The indoor ozone concentration is mainly influenced by the outdoor ozone concentration. The health effects of indoor ozone exposure have not been well studied. In contrast, there is substantial evidence of detrimental health effects from secondhand smoke. Guideline recommendations are not specific for optimizing indoor air quality. The 2007 National Asthma Education and Prevention Program asthma guidelines recommend eliminating indoor smoking and improving the ventilation. Though the guidelines state that there is insufficient evidence to recommend air cleaners, air cleaners and reducing activities that generate indoor pollutants may be sound practical approaches for improving the health of individuals with asthma. The guidelines are more specific about allergen avoidance; they recommend identifying allergens to which the individual is immunoglobin E sensitized and employing a multifaceted, comprehensive strategy to reduce exposure. Outdoor air pollutants that impact asthma include particulate matter, ozone, nitrogen dioxide, and sulfur dioxide, and guidelines recommend that individuals with asthma avoid exertion outdoors when these pollutants are elevated. Outdoor allergens include tree, grass, and weed pollens, which vary in concentration by season. Recommendations to reduce exposure include staying indoors, keeping windows and doors closed, using air conditioning and perhaps high-efficiency particulate arrestor (HEPA) air filters, and thorough daily washing to remove allergens from one's person.

Asthma disproportionately affects inner-city, minority children in the U.S. Outdoor pollutant concentrations, including particulate matter (PM), are higher in inner-cities and contribute to childhood asthma morbidity. Although children spend the majority of time indoors, indoor PM exposures have been less extensively characterized. There is a public health imperative to characterize indoor sources of PM within this vulnerable population to enable effective intervention strategies. In the present study, we sought to identify determinants of indoor PM in homes of Baltimore inner-city pre-school children. Children ages 2-6 (n=300) who were predominantly African-American (90%) and from lower socioeconomic backgrounds were enrolled. Integrated PM(2.5) and PM(10) air sampling was conducted over a 3-day period in the children's bedrooms and at a central monitoring site while caregivers completed daily activity diaries. Homes of pre-school children in inner-city Baltimore had indoor PM concentrations that were twice as high as simultaneous outdoor concentrations. The mean indoor PM(2.5) and PM(10) concentrations were 39.5+/-34.5 and 56.2+/-44.8 microg/m(3), compared to the simultaneously measured ambient PM(2.5) and PM(10) (15.6+/-6.9 and 21.8+/-9.53 microg/m(3), respectively). Common modifiable household activities, especially smoking and sweeping, contributed significantly to higher indoor PM, as did ambient PM concentrations. Open windows were associated with significantly lower indoor PM. Further investigation of the health effects of indoor PM exposure is warranted, as are studies to evaluate the efficacy of PM reduction strategies on asthma health of inner-city children.

Background: Evidence for environmental causes of asthma is limited, especially among African Americans. To look for systematic differences in early life domestic exposures between inner-city preschool children with and without asthma, we performed a study of home indoor air pollutants and allergens., Methods: Children 2-6 years of age were enrolled in a cohort study in East Baltimore, Maryland. From the child's bedroom, air was monitored for 3 days for particulate matter 0.05]. Settled dust allergen levels (cat, dust mite, cockroach, dog, and mouse) were also similar in bedrooms of asthmatic and control children., Conclusions: Exposures to common home indoor pollutants and allergens are similar for inner-city preschool children with and without asthma. Although these exposures may exacerbate existing asthma, this study does not support a causative role of these factors for risk of developing childhood asthma.

Background: Although mouse allergen exposure is common in inner-city homes, little is known about the relationships between exposure and humoral immune responses to mouse allergen in this population., Objective: To examine relationships between mouse allergen exposure and allergen-specific IgE and IgG responses in inner-city children with asthma., Methods: Inner-city children with asthma underwent skin testing and venipuncture for determination of mouse allergen-specific IgE and IgG levels. Settled dust samples were collected from their homes for allergen analysis., Results: The study population (n = 112) was predominantly African American (92%) with a mean age of 4.4 years. The prevalence rate of mouse sensitization was 25% and did not consistently increase with increasing Mus m 1 levels. Instead, the prevalence rate was lowest among those exposed to <2 microg/g, increased among those exposed to 2-7.9 microg/g and 8-29.9 microg/g, and then decreased among participants exposed to >29.9 microg/g (14%, 20%, 40%, and 28%, respectively). Similarly, the prevalence rates of mouse allergen-specific IgG and IgG(4) did not increase across increasing exposure categories. Mouse allergen-specific IgG and IgG(4) were strongly associated with IgE sensitization (odds ratios [95% CI], 82.8 [20.5-334.4] and 50.4 [14.0-181.7], respectively)., Conclusion: High-level exposure to mouse allergen in children may be associated with attenuated humoral responses of all isotypes rather than selective attenuation of IgE., Clinical Implications: Protection against allergic sensitization by high-dose allergen exposure may not be mediated by preferential production of IgG over IgE.

Background: Inner-city children experience disproportionate asthma morbidity, and suspected reasons include indoor environmental exposures., Objective: To determine if mouse allergen exposure is a risk factor for asthma morbidity., Methods: Preschool children with asthma were recruited from inner-city Baltimore, MD. Skin testing was performed and blood was collected at the baseline visit for quantification of mouse allergen specific IgE. A questionnaire evaluated symptoms, medication, and health care use at baseline, 3 months, and 6 months. A trained technician collected dust samples from the child's home for analysis of Mus m 1 at baseline, 3 months, and 6 months. Outcomes were compared between mouse-sensitized, highly exposed children and all other children., Results: A total of 127 children had complete data for mouse sensitization status and bedroom settled dust mouse allergen levels at baseline. The mean age of the children was 4.4 years, 92% were African American, and 26% were sensitized to mouse. Mouse-sensitized children exposed to higher levels of Mus m 1 (>0.5 microg/g) had 50% more days of symptoms (incidence rate ratio [IRR], 1.5; 95% confidence interval [CI], 1.1-2.1) and 80% more days of beta-agonist use than other children (IRR, 1.8; 95% CI, 1.3-2.5). Children in the sensitized and highly exposed group were also more likely to have an unscheduled physician visit (odds ratio [OR], 3.1; 95% CI, 1.6-6.3), emergency department visit (OR, 2.1; 95% CI, 1.1-4.1), and hospitalization (OR, 36.6; 95% CI, 4.1-327.3) than other children. These associations between mouse allergen exposure and asthma symptoms and morbidity remained statistically significant after adjusting for potential confounders, including atopy and cockroach sensitization and exposure., Conclusions: In mouse-sensitized inner-city children, exposure to mouse allergen may be an important cause of asthma morbidity.

This paper presents indoor air pollutant concentrations and allergen levels collected from the homes of 100 Baltimore city asthmatic children participating in an asthma intervention trial. Particulate matter (PM), NO2, and O3 samples were collected over 72 h in the child's sleeping room. Time-resolved PM was also assessed using a portable direct-reading nephelometer. Dust allergen samples were collected from the child's bedroom, the family room, and the kitchen. The mean PM10 concentration, 56.5+/-40.7 microg/m3, is 25% higher than the PM2.5 concentration (N=90), 45.1+/-37.5 microg/m3. PM concentrations measured using a nephelometer are consistent and highly correlated with gravimetric estimates. Smoking households' average PM2.5 and PM10 concentrations are 33-54 microg/m3 greater than those of nonsmoking houses, with each cigarette smoked adding 1.0 microm/m3 to indoor PM2.5 and PM10 concentrations. Large percentages of NO2 and O3 samples, 25% and 75%, respectively, were below the limit of detection. The mean NO2 indoor concentration is 31.6+/-40.2 ppb, while the mean indoor O3 concentration in the ozone season was 3.3+/-7.7 ppb. The levels of allergens are similar to those found in other inner cities. Results presented in this paper indicate that asthmatic children in Baltimore are exposed to elevated allergens and indoor air pollutants. Understanding this combined insult may help to explain the differential asthma burden between inner-city and non-inner-city children.

The environment is suspected to play an important role in the prevalence and severity of asthma in inner-city children. This paper describes the implementation and baseline data of an inner-city community-based participatory research clinical trial designed to test the effectiveness of a pollutant and allergen control strategy on children's asthma morbidity. Participants were 100 elementary-school-aged children with asthma, graduates of a school-based asthma education program in East Baltimore. The intervention for half of the randomly assigned families consisted of environmental control education, allergen-proof encasements, pest extermination, and a HEPA air cleaner at the beginning of the study. Controls received the same at the end of the study. Participants visited a clinic for questionnaires, allergy skin testing, spirometry, and blood sample at baseline and 12 months. Home environments, NO(2), O(3), airborne particulates, and allergens were evaluated at baseline and at 6 and 12 months. Asthma morbidity and adherence was assessed quarterly. Collaboration with the community proved very beneficial in creating a study design and procedures acceptable to an inner-city community.

Airborne particulate matter (PM) is hypothesized to play a role in increases in asthma prevalence, although a causal relationship has yet to be established. To investigate the effects of real-world PM exposure on airway reactivity (AHR) and bronchoalveolar lavage (BAL) cellularity, we exposed naive mice to a single dose (0.5 mg/ mouse) of ambient PM, coal fly ash, or diesel PM. We found that ambient PM exposure induced increases in AHR and BAL cellularity, whereas diesel PM induced significant increases in BAL cellularity, but not AHR. On the other hand, coal fly ash exposure did not elicit significant changes in either of these parameters. We further examined ambient PM-induced temporal changes in AHR, BAL cells, and lung cytokine levels over a 2-wk period. Ambient PM-induced AHR was sustained over 7 d. The increase in AHR was preceded by dramatic increases in BAL eosinophils, whereas a decline in AHR was associated with increases in macrophages. A Th2 cytokine pattern (IL-5, IL-13, eotaxin) was observed early on with a shift toward a Th1 pattern (IFN-gamma). In additional studies, we found that the active component(s) of ambient PM are not water-soluble and that ambient PM-induced AHR and inflammation are dose- dependent. We conclude that ambient PM can induce asthma-like parameters in naive mice, suggesting that PM exposure may be an important factor in increases in asthma prevalence.

The prevalence and severity of asthma has increased in the last 20 years, and the greatest increase has been seen among children and young adults living in U.S. inner cities. The reasons for this increase are obviously complex, but include environmental exposures to allergens and pollutants, changing patterns of medication, and the psychosocial stresses of living in poor inner-city neighborhoods. This paper presents an overview of environmental, immunologic, and genetic factors associated with asthma morbidity and mortality. This overview can be used to provide a framework for designing an interdisciplinary research program to address the complexities of asthma etiology and exacerbation. The strongest epidemiologic association has been found between asthma morbidity and the exposure of immunologically sensitive asthmatic patients to airborne allergens. Our current understanding of the process of sensitization suggests that there is a strong genetic predisposition to form IgE to allergenic proteins on airborne particles. Much of this work has been conducted with animal models, but in a number of instances, specific confirmation has been reported in humans. Sensitized individuals respond to inhaled exposure with immediate mast-cell dependent inflammation that may be augmented by pollutant particles, especially diesel exhaust particles. Relatively little is known about the methods of assessing exposure to airborne pollutants, especially biologically active particulates. However, to examine the relationship of morbidity in genetically predisposed individuals, it will be important to determine the most relevant method of making this assessment.