Asthma in the inner city and the indoor environment

Offspring behavioral outcomes following maternal allergic asthma in the IL-4-deficient mouse

Maternal allergic asthma (MAA) during pregnancy has been associated with increased risk of neurodevelopmental disorders in humans, and rodent studies have demonstrated that inducing a T helper-2-mediated allergic response during pregnancy leads to an offspring behavioral phenotype characterized by decreased social interaction and increased stereotypies. The interleukin (IL)-4 cytokine is hypothesized to mediate the neurobehavioral impact of MAA on offspring. Utilizing IL-4 knockout mice, this study assessed whether MAA without IL-4 signaling would still impart behavioral deficits. C57 and IL-4 knockout female mice were sensitized to ovalbumin, exposed to repeated MAA inductions, and their offspring performed social, cognitive, and motor tasks. Only C57 offspring of MAA dams displayed social and cognitive deficits, while IL-4 knockout mice showed altered motor activity compared with C57 mice. These findings highlight a key role for IL-4 signaling in MAA-induced behavioral deficits and more broadly in normal brain development.

The influence of asthma on neuroinflammation and neurodevelopment: From epidemiology to basic models

Asthma is a highly heterogeneous inflammatory disease that can have a significant effect on both the respiratory system and central nervous system. Population based studies and animal models have found asthma to be comorbid with a number of neurological conditions, including depression, anxiety, and neurodevelopmental disorders. In addition, maternal asthma during pregnancy has been associated with neurodevelopmental disorders in the offspring, such as autism spectrum disorders and attention deficit hyperactivity disorder. In this article, we review the most current epidemiological studies of asthma that identify links to neurological conditions, both as it relates to individuals that suffer from asthma and the impacts asthma during pregnancy may have on offspring neurodevelopment. We also discuss the relevant animal models investigating these links, address the gaps in knowledge, and explore the potential future directions in this field.

Characterizing the neuroimmune environment of offspring in a novel model of maternal allergic asthma and particulate matter exposure

Inflammation during pregnancy is associated with an increased risk for neurodevelopmental disorders (NDD). Increased gestational inflammation can be a result of an immune condition/disease, exposure to infection, and/or environmental factors. Epidemiology studies suggest that cases of NDD are on the rise. Similarly, rates of asthma are increasing, and the presence of maternal asthma during pregnancy increases the likelihood of a child being later diagnosed with NDD such as autism spectrum disorders (ASD). Particulate matter (PM), via air pollution, is an environmental factor known to worsen the symptoms of asthma, but also, PM has been associated with increased risk of neuropsychiatric disorders. Despite the links between asthma and PM with neuropsychiatric disorders, there is a lack of laboratory models investigating combined prenatal exposure to asthma and PM on offspring neurodevelopment. Thus, we developed a novel mouse model that combines exposure to maternal allergic asthma (MAA) and ultrafine iron-soot (UIS), a common component of PM. In the current study, female BALB/c mice were sensitized for allergic asthma with ovalbumin (OVA) prior to pregnancy. Following mating and beginning on gestational day 2 (GD2), dams were exposed to either aerosolized OVA to induce allergic asthma or phosphate buffered saline (PBS) for 1 h. Following the 1-h exposure, pregnant females were then exposed to UIS with a size distribution of 55 to 169 nm at an average concentration of 176 ± 45 μg/m3) (SD), or clean air for 4 h, over 8 exposure sessions. Offspring brains were collected at postnatal days (P)15 and (P)35. Cortices and hippocampal regions were then isolated and assessed for changes in cytokines using a Luminex bead-based multiplex assay. Analyses identified changes in many cytokines across treatment groups at both timepoints in the cortex, including interleukin-1 beta (IL-1β), and IL-17, which remained elevated from P15 to P35 in all treatment conditions compared to controls. There was a suppressive effect of the combined MAA plus UIS on the anti-inflammatory cytokine IL-10. Potentially shifting the cytokine balance towards more neuroinflammation. In the hippocampus at P15, elevations in cytokines were also identified across the treatment groups, namely IL-7. The combination of MAA and UIS exposure (MAA-UIS) during pregnancy resulted in an increase in microglia density in the hippocampus of offspring, as identified by IBA-1 staining. Together, these data indicate that exposure to MAA, UIS, and MAA-UIS result in changes in the neuroimmune environment of offspring that persist into adulthood.

Characterizing the Neuroimmune Environment of Offspring in a Novel Model of Maternal Allergic Asthma and Particulate Matter Exposure

Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by the presence of decreased social interactions and an increase in stereotyped and repetitive behaviors. Epidemiology studies suggest that cases of ASD are on the rise. Similarly, rates of asthma are increasing, and the presence of maternal asthma during pregnancy increases the likelihood of a child being later diagnosed with ASD. Particulate matter (PM), via air pollution, is an environmental factor known to worsen the symptoms of asthma, but also, PM has been associated with increased risk of neuropsychiatric disorders including ASD. Despite the links between asthma and PM with neuropsychiatric disorders, there is a lack of laboratory models investigating combined prenatal exposure to asthma and PM on offspring neurodevelopment. Thus, we developed a novel mouse model that combines exposure to maternal allergic asthma (MAA) and ultrafine iron-soot (UIS), a common component of PM. In the current study, female BALB/c mice were primed for allergic asthma with ovalbumin (OVA) prior to pregnancy. Following mating and beginning on gestational day 2 (GD2), dams were exposed to either aerosolized OVA or phosphate buffered saline (PBS) for 1 hour. Following the 1-hour exposure, pregnant females were then exposed to UIS or clean air for 4 hours. Offspring brains were collected at postnatal days (P)15 and (P)35. Cortices and hippocampal regions were then isolated and assessed for changes in cytokines using a Luminex bead-based multiplex assay. Analyses identified changes in many cytokines across treatment groups at both timepoints in the cortex, including interleukin-1 beta (IL-1β), IL-2, IL-13, and IL-17, which remained elevated from P15 to P35 in all treatment conditions compared to controls. In the hippocampus at P15, elevations in cytokines were also identified across the treatment groups, namely interferon gamma (IFNγ) and IL-7. The combination of MAA and UIS exposure (MAA-UIS) during pregnancy resulted in an increase in microglia density in the hippocampus of offspring, as identified by IBA-1 staining. Together, these data indicate that exposure to MAA, UIS, and MAA-UIS result in changes in the neuroimmune environment of offspring that persist into adulthood.

Detection and assessment of dust mite allergens in an indoor environment in Anhui, China

Dust in the home environment is thought to be a potential trigger for increasing allergic diseases, such as allergic rash, rhinitis, asthma, and other conditions, associated with dust mites. To verify the status of dust mite prevalence in indoor surroundings, we collected 189 dust samples from the air conditioner filters (n = 75) and floors (n = 114) of households, schools, and hotels in the Anhui area, China. All samples were measured for dust mite breeding rate and breeding density under light microscopy and analyzed for dust mite species Dermatophagoides farinae 1 (Der f 1) and Dermatophagoides pteronyssinus 1 (Der p 1) allergen using enzyme-linked immunosorbent assay (ELISA). The dust mite breeding rates were 34.67% (26/75) and 20.18% (23/114), respectively, in the dust samples from the floor and air conditioning filters. The breeding density was the highest in households (10/g), followed by schools (9/g) and hotels (4/g). ELISA indicated that the allergen threshold (2.0 µg/g dust) of Der f 1 was exceeded in only two samples and Der p 1 in one sample. Additionally, a questionnaire was used to investigate the health knowledge on allergic diseases involved in indoor facilities, finding that most allergy sufferers were aware that indoor dust might be responsible for their conditions. The findings suggest that regular maintenance of indoor hygiene and cleaning of air-conditioning filters should reduce the risks of exposure to indoor allergens.

The association between air pollution and childhood asthma: United States, 2010-2015

OBJECTIVE

The current population-based study examines the association between county-level ambient air pollution and childhood asthma.

METHODS

Data from the nationally representative 2010-2015 National Health Interview Survey were linked to nationwide fine particulate matter (PM2.5) air pollution data at the county-level from the National Environmental Public Health Tracking Network which utilizes air quality monitoring stations and modeled PM2.5 measurements (Downscaler model data) and adjusted by county-level socioeconomic characteristics data from the 2010-2015 American Community Survey. Multilevel modeling techniques were used to assess the association between PM2.5 annual concentrations (quartiles < 8.11, 8.11-9.50, 9.51-10.59, ≥ 10.60 µg/m3) and current childhood asthma along with two asthma outcomes (episode in the past year, emergency room (ER) visit due to asthma).

RESULTS

From 2010 to 2015, there were significant declines in PM2.5 concentrations and asthma outcomes. In unadjusted models, children living in areas with higher PM2.5 concentrations were more likely to have current asthma, ≥1 asthma episode in the past year, and ≥1 ER visit due to asthma compared with children living in areas with the lowest quartile (< 8.11 µg/m3). After adjusting for characteristics at the county, geographic, and child and family-level, significant associations remained for asthma episode, and ER visit among children living in areas with PM2.5 annual concentrations between 9.51 and 10.59 µg/m3 (3rd quartile) compared with children living in areas with the lowest quartile.

CONCLUSIONS

This study adds to the limited literature by incorporating nationally representative county-, child-, and family-level data to provide a multi-level analysis of the associations between air pollution and childhood asthma in the U.S.

Patterns and predictors of air purifier adherence in children with asthma living in low-income, urban households

OBJECTIVE

Black children and children from low-income communities are disproportionately affected by asthma, attributed partly to pollution exposure. Air purifiers reduce indoor air pollution and improve asthma symptoms in children. In order to implement air purifier interventions, an understanding of patterns of use and potential barriers is necessary.

METHODS

In a home intervention study, 127 children with asthma living in Baltimore were randomized to receive two active or two placebo air purifiers. The 16-week study period included: baseline clinic visit, home visit for air purifier installation (active or placebo) with instruction to use the high or turbo settings, and electronic adherence monitoring of air purifiers. Determinants of adherence were identified using linear regression models.

RESULTS

Air purifiers were used 80% of the time, and participants demonstrated adherence to high or turbo settings for 60% of the time. In an adjusted model, season was the major determinant of air purifier adherence, with 21% lower use in the winter (p = 0.025) attributed to the cold draft generated by the machine.

CONCLUSION

In a clinical trial with electronic adherence monitoring, air purifier use was high and participants were adherent to use of high or turbo settings the majority of the time. Addressing practical barriers to consistent use, such as draft during the winter, in addition to financial barriers may improve air purifier adherence among children with asthma living in low-income, urban households.

CLINICAL TRIALS REGISTRY NUMBER

NCT02763917.

Residential environment in relation to self-report of respiratory and asthma symptoms among primary school children in a high-polluted urban area

Respiratory disease and its complication are the cause of children deaths worldwide every year. Several epidemiological studies pointed out an association between quality of residential in inner city and risk of children health. However, few studies had been focused in high-polluted urban area in low to middle income countries. A cross-sectional study was conducted to investigate the association between residential environments and respiratory symptoms including asthma among 658 primary school children living in urban area of Bangkok Thailand. The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was modified to access symptoms during the past 12 months. Binary logistic regression model was performed. Living near garment and clothing shop is associated with shortness of breath (AOR = 1.846; 95% CI 1.034, 3.297). Vectors in home is related to dry cough at night (AOR = 1.505; 95% CI 1.052, 2.153) and phlegm (AOR = 1.414; 95% CI 1.014, 1.973). Wall dampness is increased odd of having wheezing or whistling (asthma) in the chest (AOR = 1.921; 95% CI 1.141, 3.235). Children age, gender, and a family history of asthma were modified the associations. Our finding may provide strategies focusing on living environment improvement with a specific group of children to address respiratory disease prevention.

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.

Material Hardship and Indoor Allergen Exposure among Low-Income, Urban, Minority Children with Persistent Asthma

Traditional measures of socioeconomic status (SES) are associated with asthma morbidity, but their specific contributions are unclear. Increased exposure to indoor allergens among low SES children is an important consideration. Material hardship, a concept describing poor access to basic goods and services, may explain the relationship between low SES and indoor allergen exposure, and thereby, the increased risk of asthma morbidity. We sought to (i) describe the specific hardships experienced by low-Income, urban, minority children with asthma and indoor allergen sensitization and (ii) determine if material hardship is associated with indoor allergen exposure in this population. We conducted a cross-sectional analysis of children undergoing the baseline assessment for a clinical trial of home environmental modification. Participants were scored in five domains of material hardship. Domain scores were assigned based on caregiver responses to a questionnaire and were summed to generate a total material hardship score. Linear regression was used to examine the relationship between material hardship scores and bedroom floor concentrations of five common indoor allergens. Participants experienced high levels of material hardship in each of the five domains, with 33% not having access to a car, 35% not being able to pay utility bills, and 28% not being able to pay rent in the past year. Each one-point increase in material hardship was associated with an increase in cockroach allergen of 16.2% (95% CI 9.4%, 24.6%) and an increase in mouse allergen of 9.4% (95% CI 1.0%, 18.5%). After adjusting for traditional measures of SES, including household income, health insurance type, caregiver education, and caregiver employment status, the association between material hardship and cockroach allergen, but not mouse allergen, remained. These data suggest that a significant proportion of families of low-income, minority children with asthma may experience material hardship, and that they may be at greater risk of cockroach allergen exposure than their peers with similar income, but without material hardship.

Correlation of acidic mammalian chitinase expression with disease severity in patients with moderate/severe persistent allergic rhinitis

Aim of the study

To assess the level of acidic mammalian chitinase (AMCase) expression and IL-8 in nasal inferior turbinate mucosa in patients with mild and moderate to severe allergic rhinitis (AR).

Material and methods

Participants in this case-control study were divided into three groups, including patients with moderate and severe persistent allergic rhinitis, cases with mild forms of persistent AR, and control or healthy group. We obtained biopsies of nasal inferior turbinate mucosa from all participants. Expression of AMCase and IL-8 mRNAs were evaluated by real-time polymerase chain reaction (PCR). The serum levels of AMCase and IL-8 were determined by ELISA. The number of eosinophils per field, blood eosinophils, total serum IgE levels, and specific serum IgE levels were measured. Patients’ clinical manifestations were assessed by total nasal syndrome score (TNSS).

Results

Expression of AMCase and IL-8 in patients with moderate and severe perineal allergic rhinitis were significantly elevated compared to the control group and patients with mild persistent allergic rhinitis. Serum levels of AMCase and IL-8 were associated with specific IgE, nasal eosinophil count, and TNSS.

Conclusions

According to the results of this study, there might be a relationship between the expression of AMCase and IL-8 in nasal turbinate mucosa and the severity of allergic rhinitis.

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.

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.

Antenatal active maternal asthma and other atopic disorders is associated with ADHD behaviors among school-aged children

BACKGROUND

Identifying modifiable risk factors for neuropsychological correlates of attention deficit hyperactivity disorder (ADHD) in early childhood can inform prevention strategies. Prenatal inflammatory states, such as maternal asthma and other atopic disorders, have been increasingly linked to enhanced risk for neurobehavioral disorders in children, with some studies suggesting sex-specific effects.

OBJECTIVES

To assess the association between maternal active asthma and/or atopy in the antenatal period and child symptoms of ADHD during mid-childhood and, given the male-bias in ADHD prevalence, to examine modifying effects of child sex.

STUDY DESIGN

The study sample includes 250 maternal-child pairs enrolled in the Boston-based Asthma Coalition on Community, Environment and Social Stress (ACCESS) pregnancy cohort. We defined antenatal active atopy based on maternal report of current asthma, allergic rhinitis or atopic dermatitis during and/or in the year before pregnancy. When children were approximately 6 years old, mothers completed a battery of standardized child behavior rating scales designed for evaluating symptoms of ADHD. We used multivariable quantile regression to assess the relations between maternal antenatal atopy and symptoms of ADHD among children.

RESULTS

In adjusted models, maternal atopy was significantly associated with greater risk for ADHD behaviors, as indicated by scores on the Conners' Parent Rating Scale-Revised ADHD index (β = 3.32, 95% CI: 0.33, 6.32). In sex-stratified models this association was stronger among girls (5.96, 95% CI = 0.95, 10.96) compared to boys (-2.14, 95% CI = -5.75, 1.45, p-interaction = 0.01). Among girls, we observed a similar finding for the Behavior Assessment System for Children 2nd Edition Parent Rating Scale Attention Problems subscale (β = 7.77, 95% CI = 1.57, 13.97). Results from other outcome subscales were similar in magnitude and direction, however, associations did not reach statistical significance at the p = 0.05 level.

CONCLUSIONS

Maternal antenatal active atopy may be a risk factor for the development of ADHD-like symptoms, especially among girls.

Detection and identification of dust mite allergens in the air conditioning filters in Chandigarh, India

Modern lifestyle with the increasing use of air conditioner (AC) has been linked with breathing difficulties, irritation, dryness, and other symptoms. Hence, dust mites were isolated from AC filters, which causes allergic diseases. A total of 95 dust samples were collected from AC filters from hospitals, guest house, office, school, and homes in Chandigarh, India. The highest concentration of dust mites was detected from hospitals (9/g), offices (7/g), households (6/g), guest houses (3/g), and schools (0/g). Based on the morphology of dust mites observed under a light microscope, Dermatophagoides and Acarus species were found most common. Indoor air quality was also monitored to find out their relation with dust mites present in AC filters. Further, the respiratory health status of indoor facility users was also assessed using a standard questionnaire as a study tool. It was seen that 55.3% of male among the total respondents were having an allergy and only 44.7% of the females had an allergy. The allergy among the male respondents (55.3%) was significantly more (p < 0.05) in comparison with female respondents (44.7%). Some of the respondents also reported a family history of rhinitis (31.9%), asthma (12.8%), recurrent urticaria (6.4%), and conjunctivitis (6.4%). Interestingly, 23.4% of study participants reported that they get disturbed by the use of AC and house dust was found to be the most triggering factor in enhancing the symptoms of allergy. Thus, it is recommended that air conditioner filters should be cleaned regularly to prevent the accumulation of the dust mites and related allergens on filter dust.

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.

Environmental and molecular study of fungal flora in asthmatic patients

The aim of the present study was to investigate the epidemiological and fungal environmental profile in asthmatic patients. We conducted a prospective study involving 49 patients with allergic asthma. One hundred and forty-five clinical samples and 289 environmental samples were performed. Only 30 patients accepted to participate to the environmental study at their home. For specific IgE antibodies, ELISA assay was conducted for 21 patients. Molecular ITS sequencing was performed for 37 isolates. The frequency of attacks was significantly associated with the seasonality, which was closely related to climate (P=0.024), exposure to animals (cats, P=0.025), plants (olive, P=0.018), physical effort (P=0.04) and the number of permanent occupants in house (>6) (P=0.026). Fungal contaminants were detected from 78.6% of biological samples and 97.8% of environmental samples. Antibodies corresponding to the studied allergens were detected in 10 patients (10/21). PCR sequencing allowed as rectified morphological identification for 27.02% (10/37) strains of Aspergillus. The allergy in molds is an indisputable reality that is necessary to look for in front of any severe asthma. So, it is important to establish clearly a relationship between exposure to fungi and health disorders in order to set up specific and effective preventive measures.

Primary Care Issues in Inner-City America and Internationally

Inner-city patient populations are high-risk for poor outcomes, including increased risk of mortality. Barriers to delivering high-quality primary care to inner-city patients include lack of access, poor distribution of primary care providers (PCPs), competing demands, and financial restraints. Health care issues prevalent in this population include obesity, diabetes, cancer screening, asthma, infectious diseases, and obstetric and prenatal care. Population health management and quality improvement (QI) activities must target disparities in care. Partnering with patients and focusing on social determinants of health andmedical care are key areas inwhich to focus toimprove overall healthoutcomes inthispopulation.

Racial and Ethnic Differences in Pediatric Readmissions for Common Chronic Conditions

OBJECTIVE

To compare the timing and magnitude of variation of pediatric readmission rates across race/ethnicity for selected chronic conditions: asthma, diabetes, seizures, migraines, and depression.

STUDY DESIGN

Retrospective analysis of hospitalizations at 48 children's hospitals in the 2013 Pediatric Health Information System database for children (ages 0-18 years) admitted for asthma (n = 36 910), seizure (n = 35 361), diabetes (n = 12 468), migraine (n = 5882), and depression (n = 5132). Generalized linear models with a random effect for hospital were used to compare the likelihood of readmission by patients' race/ethnicity, adjusting for severity of illness, age, payer, and medical complexity. Adjusted readmission rates were calculated by week over 1 year.

RESULTS

Significant variation in adjusted readmission rates by race/ethnicity existed for conditions aside from depression. Disparities for diabetes and asthma emerged at 3 and 4 weeks, respectively; they remained divergent up to 1 year with the highest 1-year readmission rates in non-Hispanic blacks vs other race/ethnicities (diabetes: 21.7% vs 13.4%, P < .001; asthma: 21.4% vs 14.6%, P < .001). Disparities for migraines and seizure emerged at 6 and 7 weeks, respectively; they remained up to 1 year, with the highest 1-year readmission rates in non-Hispanic whites vs other race/ethnicities (migraine: 17.3% vs 13.6%, P < .001; seizure: 23.9% vs 21.9%, P < .001).

CONCLUSIONS

Readmission disparities behave differently across chronic conditions. They emerge more quickly after discharge for children hospitalized with asthma or diabetes than for seizures or migraines. The highest readmission rates were not consistently observed for 1 particular race/ethnicity. Study findings can impact pediatric chronic disease management to improve care for children with these conditions.

Analysis of home dust for Staphylococcus aureus and staphylococcal enterotoxin genes using quantitative PCR

BACKGROUND

The bacterium Staphylococcus aureus (SA) is known to induce allergic inflammatory responses, including through secreted staphylococcal enterotoxin (SE) superantigens. To quantify indoor environmental exposures to these potential allergens, which may be associated with worse asthma, we developed a method for the assessment of S. aureus and SE in home dust and applied it to a study of homes of inner-city adults with asthma.

METHODS

We conducted laboratory experiments to optimize sample processing and real-time PCR methods for detection and quantification of SA (femB) and SEA-D, based on published primers. We applied this method to dust and dust extract from 24 homes. We compared results from real-time PCR to culture-based results from the same homes.

RESULTS

The bacteremia DNA isolation method provided higher DNA yield than alternative kits. Culture-based results from homes demonstrated 12 of 24 (50%) bedrooms were contaminated with S. aureus, only one of which carried a SE gene (SEC). In contrast, femB was detected in 23 of 24 (96%) bedrooms with a median of 1.1×10⁶ gene copies detected per gram of raw dust. Prevalence and median copy number (shown in parenthesis) of SE gene detection in bedroom dust was: SEA 25% (1.4×10²); SEB 63% (1.4×10³); SEC 63% (1.1×10³); SED 21% (1.3×10²).

CONCLUSIONS

Our culture-independent method to detect S. aureus and SE in home dust was more sensitive than our culture-based method. Prevalence of household exposure to S. aureus and SE allergens may be high among adults with asthma.

Mould and grass pollen allergy as risk factors for childhood asthma in Zaragoza, Spain

OBJECTIVE

Examine the prevalence of asthma and associated predictive factors in a group of 468 students.

PATIENTS AND METHODS

A descriptive, cross-sectional observational study in a randomly selected population of 468 children aged 10-12, in the city of Zaragoza. We used the ISAAC questionnaire on asthma completed by children under supervision of the investigators. We assessed the genetic risk (family history of asthma) and environmental risks. The risk for atopy was assessed by the presence of positive skin prick tests.

RESULTS

25.3% of the children had symptoms consistent with asthma in the city of Zaragoza. Among them 33.1% reported a history of asthma in close relatives (OR=1.78, p<0.001). The history of hospitalisations for lower respiratory tract illness was strongly associated with the presence of asthma (OR=6.72, p<0.0001). Positive skin tests to Alternaria (OR=2.00, p<0.0001) and grass pollen (OR=1.76, p<0.001) were predictors of asthma. 63.6% of asthmatic children had presented clinical rhinitis in the previous 12 months, compared with 32% of non-asthmatics, and this difference was statistically significant (OR=3.89, p<0.0001). 47% of asthmatics presented with or previously had eczema, whereas only 26.9% of non-asthmatics presented with or previously had these types of lesions (p<0.0001).

CONCLUSION

The following are predictors of asthma: History of hospital admissions for lower respiratory tract illness, presence of rhinitis and/or eczema, positive prick test for certain aeroallergens, especially Alternaria and grass pollen, and family history of asthma.

The influence of atopy and asthma on immune responses in inner-city adults

Asthma in the inner‐city population is usually atopic in nature, and is associated with significant morbidity and mortality. However, the underlying immune abnormalities that underlie asthma in urban adults have not been well defined. We investigated the influence of atopy and asthma on cytokine responses of inner‐city adult women to define immune abnormalities associated with asthma and atopy. Blood samples were collected from 509 of 606 inner‐city women enrolled in the Urban Environment and Childhood Asthma (URECA) study. We tested for associations between atopy and asthma status and cytokine responses in peripheral blood mononuclear cells incubated ex vivo with a panel of innate and adaptive immune stimulants. Atopic subjects had heightened Th2 cytokine responses (IL‐4, IL‐5, IL‐13) to cockroach and dust mite antigens, tetanus toxoid, and phytohemagglutinin (P < 0.05 for all). Differences in cytokine responses were greatest in response to stimulation with cockroach and dust mite. In a multivariate analysis, atopy was broadly related to increased Th2‐like responses to all antigens and PHA, while asthma was only weakly related to mitogen‐induced IL‐4 and IL‐5 responses. There were few asthma or allergy‐related differences in responses to innate stimuli, including IFN‐α and IFN‐γ responses. In this inner‐city adult female population, atopy is associated with enhanced Th2 responses to allergens and other stimuli, and there was little or no additional signal attributable to asthma. In particular, these data indicate that altered systemic interferon and innate immune responses are not associated with allergies and/or asthma in inner‐city women.

Case-control study evaluating competing risk factors for angioedema in a high-risk population

OBJECTIVES/HYPOTHESIS

Black race is a risk factor for angioedema. The primary aim was to examine the relationship between race-ethnicity and risk factors for angioedema.

STUDY DESIGN

Using a retrospective case-control study design, data was extracted with the Clinical Looking Glass utility, a data collection and management tool that captures data from electronic medical record systems within the Montefiore Healthcare System. Cases were emergency department (ED) visits with primary or secondary International Classification of Diseases, Ninth Revision, code diagnoses of angioedema in adults aged ≥ 18 years from January 2008 to December 2013 at three Montefiore centers in Bronx, New York. Controls were a random sampling of adult ED visits during the same period.

METHODS

In primary analyses, angiotensin-converting enzyme inhibitor (ACE-I) and black race were evaluated for synergy. The influence of different risk factors in the development of angioedema was evaluated using logistic regression models. Finally, race-ethnicity was further explored by evaluating for effect modification by stratification of models by race-ethnicity categories.

RESULTS

There were 1,247 cases and 6,500 controls randomly selected from a larger control pool. ACE-I use (odds ratio [OR] 3.70, 95% confidence interval [CI] 2.98, 4.60), hypertension (OR 1.88, 95% CI 1.55, 2.29), and black race (OR 2.25, 95% CI 1.86, 2.72) were the strongest risk factors. ACE-I use and black race were not synergistic (OR 1.10, 95% CI 0.80, 1.51). Race-ethnicity was an effect modifier for certain risk factors.

CONCLUSION

Race-ethnicity acts as an effect modifier for particular angioedema risk factors. The two strongest risk factors, ACE-I use and black race, were not synergistic.

LEVEL OF EVIDENCE

3b. Laryngoscope, 126:1823-1830, 2016.

Endotoxin Exposure: Predictors and Prevalence of Associated Asthma Outcomes in the United States

RATIONALE

Inhaled endotoxin induces airway inflammation and is an established risk factor for asthma. The 2005-2006 National Health and Nutrition Examination Survey included measures of endotoxin and allergens in homes as well as specific IgE to inhalant allergens.

OBJECTIVES

To understand the relationships between endotoxin exposure, asthma outcomes, and sensitization status for 15 aeroallergens in a nationally representative sample.

METHODS

Participants were administered questionnaires in their homes. Reservoir dust was vacuum sampled to generate composite bedding and bedroom floor samples. We analyzed 7,450 National Health and Nutrition Examination Survey dust and quality assurance samples for their endotoxin content using extreme quality assurance measures. Data for 6,963 subjects were available, making this the largest study of endotoxin exposure to date. Log-transformed endotoxin concentrations were analyzed using logistic models and forward stepwise linear regression. Analyses were weighted to provide national prevalence estimates and unbiased variances.

MEASUREMENTS AND MAIN RESULTS

Endotoxin exposure was significantly associated with wheeze in the past 12 months, wheeze during exercise, doctor and/or emergency room visits for wheeze, and use of prescription medications for wheeze. Models adjusted for age, sex, race and/or ethnicity, and poverty-to-income ratio and stratified by allergy status showed that these relationships were not dependent upon sensitization status but were worsened among those living in poverty. Significant predictors of higher endotoxin exposures were lower family income; Hispanic ethnicity; participant age; dog(s), cat(s), cockroaches, and/or smoker(s) in the home; and carpeted floors.

CONCLUSIONS

In this U.S. nationwide representative sample, higher endotoxin exposure was significantly associated with measures of wheeze, with no observed protective effect regardless of sensitization status.

Polycyclic aromatic hydrocarbons and childhood asthma

Asthma is the most common chronic illness in children living in developed countries and the leading cause of childhood hospitalization and school absenteeism. Prevalence rates of asthma are increasing and show disparities across gender, geographic regions, and ethnic/racial groups. Common risk factors for developing childhood asthma include exposure to tobacco smoke, previous allergic reactions, a family history of asthma, allergic rhinitis or eczema, living in an urban environment, obesity and lack of physical exercise, severe lower respiratory tract infections, and male gender. Asthma exacerbation in children can be triggered by a variety of factors, including allergens (e.g., pollen, dust mites, and animal dander), viral and bacterial infections, exercise, and exposure to airway irritants. Recent studies have shown that exposure to polycyclic aromatic hydrocarbons (PAHs), a major component of fine particulate matter from combustion sources, is also associated with onset of asthma, and increasing asthmatic symptoms. In this paper, we review sources of childhood PAH exposure and the association between airborne PAH exposure and childhood asthma prevalence and exacerbation.

Associations of neighborhood concentrated poverty, neighborhood racial/ethnic composition, and indoor allergen exposures: a cross-sectional analysis of los angeles households, 2006-2008

Although racial/ethnic, socioeconomic, and neighborhood factors have been linked to asthma, and the association between indoor allergens and asthma is well documented, few studies have examined the relationship between these factors and indoor allergens. We examined the frequency of reported indoor allergens and differences by racial/ethnic, socioeconomic, and neighborhood characteristics among a diverse sample of Los Angeles households. Multilevel logistic regression models were used to analyze the data from 723 households from wave 2 of the Los Angeles Family and Neighborhood Survey. The reported presence of rats, mice, cockroaches, mold, pets, and tobacco smoke were the primary outcomes of interest. Hispanic and Asian households had a nearly threefold increase in the odds of reporting cockroaches compared to non-Hispanic Whites (OR, 2.85; 95 % CI 1.38-5.88 and OR, 2.62; 95 % CI 1.02-6.73, respectively) even after adjusting for socioeconomic factors. Primary caregivers who had obtained a high school degree were significantly less likely to report the presence of mice and cockroaches compared to primary caregivers with less than a high school degree (OR, 0.19; 95 % CI 0.08-0.46 and OR, 0.39; 95 % CI 0.23-0.68, respectively). Primary caregivers with more than a high school degree were also less likely to report the presence of rats, mice, and cockroaches within their households, compared to those with less than a high school degree. Compared to renters, home owners were less likely to report the presence of mice, cockroaches, and mold within their households. At the neighborhood level, households located within neighborhoods of high concentrated poverty (where the average poverty rate is at least 50 %) were more likely to report the presence of mice and cockroaches compared to households in low concentrated poverty neighborhoods (average poverty rate is 10 % or less), after adjusting for individual race/ethnicity and socioeconomic characteristics. Our study found evidence in support of neighborhood-level racial/ethnic and socioeconomic influences on indoor allergen exposure, above and beyond individual factors. Future studies should continue to explore individual and neighborhood-level racial/ethnic and socioeconomic differences in household allergen exposures across diverse contexts.

Effects of early-life exposure to allergens and bacteria on recurrent wheeze and atopy in urban children

BACKGROUND

Wheezing illnesses cause major morbidity in infants and are frequent precursors to asthma.

OBJECTIVE

We sought to examine environmental factors associated with recurrent wheezing in inner-city environments.

METHODS

The Urban Environment and Childhood Asthma study examined a birth cohort at high risk for asthma (n = 560) in Baltimore, Boston, New York, and St Louis. Environmental assessments included allergen exposure and, in a nested case-control study of 104 children, the bacterial content of house dust collected in the first year of life. Associations were determined among environmental factors, aeroallergen sensitization, and recurrent wheezing at age 3 years.

RESULTS

Cumulative allergen exposure over the first 3 years was associated with allergic sensitization, and sensitization at age 3 years was related to recurrent wheeze. In contrast, first-year exposure to cockroach, mouse, and cat allergens was negatively associated with recurrent wheeze (odds ratio, 0.60, 0.65, and 0.75, respectively; P ≤ .01). Differences in house dust bacterial content in the first year, especially reduced exposure to specific Firmicutes and Bacteriodetes, was associated with atopy and atopic wheeze. Exposure to high levels of both allergens and this subset of bacteria in the first year of life was most common among children without atopy or wheeze.

CONCLUSIONS

In inner-city environments children with the highest exposure to specific allergens and bacteria during their first year were least likely to have recurrent wheeze and allergic sensitization. These findings suggest that concomitant exposure to high levels of certain allergens and bacteria in early life might be beneficial and suggest new preventive strategies for wheezing and allergic diseases.

Exposure to multiwalled carbon nanotubes and allergen promotes early- and late-phase increases in airway resistance in mice

The facilitating effects of multiwalled carbon nanotubes (MWCNT) on allergic asthma have not been sufficiently examined, although MWCNT appear to significantly increase the risk of health problems from occupational or environmental exposure. In this study, we examined whether sensitization by the combination of MWCNT with ovalbumin (OVA) promotes allergic asthmatic responses. BALB/c mice administered vehicle, MWCNT, OVA, or MWCNT+OVA through an intranasal route were challenged with OVA intratracheally four times. In the MWCNT+OVA group, the fourth challenge caused not only early- but also late-phase increases in airway resistance, although these responses were not observed in the vehicle, MWCNT, or OVA group; furthermore, the extents of the early and late responses were comparable to those in mice systemically sensitized with OVA+alum. Sensitization with MWCNT and OVA promoted airway inflammation and goblet cell hyperplasia in the lung compared with the vehicle, MWCNT or OVA group. In addition, adjuvant activity for OVA-specific immunoglobulin E (IgE), IgG1, and IgG2a production in serum and increased levels of interleukin-4 (IL-4), IL-5, IL-13, and IL-17 in the lung tissue were observed. In conclusion, these results suggest that exposure to MWCNT and antigen can induce a biphasic increase in airway resistance, airway inflammation, goblet cell hyperplasia, and the production of antigen-specific antibodies. This study highlights the risk of exposure to a combination of MWCNT with antigen.

[Indoor air quality and adult asthma]

INTRODUCTION

Asthma is a chronic inflammatory disease of the airways. The recent increase in its global prevalence suggests a possible role of environmental factors such as indoor air pollution. In 2000, according to the Institute Of Medicine, there was insufficient evidence to determine whether or not an association existed between high priority indoor air pollutants, listed by the French Indoor Air Quality Observatory, and asthma. The objective of this paper is to describe the current state of knowledge on the links between exposure to high priority indoor air pollutants and exacerbations of adult asthma.

METHOD

A review of the Medline database has been undertaken of the following pollutants: formaldehyde, benzene, acetaldehyde, volatile organic compounds, particles (PM2.5, PM10) and diethylhexyl-phthalate. The studies were classified by type and source of pollutant.

RESULTS

Twenty-three studies were included in the analysis. Most of the observational studies have shown an association between pollutants (by type and source) and adult asthma. The best documented pollutants were formaldehyde and volatile organic compounds. No studies were found on acetaldehyde and diethylhexyl-phthalate.

CONCLUSION

The analysis of the literature is complicated on account of the difficulty of comparing different studies. However, since the synthesis performed in 2000, the existence of a link between chemical indoor air pollutants and increased respiratory symptoms appears to be reinforced. It seems necessary to adopt preventive health measures while pursuing scientific research on this topic.

Impact of the environment on asthma control

Asthma is a complex condition that requires individualized interventions. The purpose of this article is to describe the relationship between the physical and social environments with asthma symptoms, present evidence that supports environmental interventions in asthma control and the implications for asthma management. There is evidence that indoor and outdoor allergens relate to asthma morbidity. Knowledge about which environmental exposures present risk is essential because many of these exposures can be modified, reduced, or eliminated. The community health nurse should provide care relative to the client's indoor and outdoor environment and existing allergens.

Asthma and the achievement gap among urban minority youth

OBJECTIVES

To outline the prevalence and disparities of asthma among school-aged urban minority youth, causal pathways through which poorly controlled asthma adversely affects academic achievement, and proven or promising approaches for schools to address these problems.

METHODS

Literature review.

RESULTS

Asthma is the most common chronic disease affecting youth in the United States; almost 10 million youth under 18 (14%) have received a diagnosis and 6.8 million (9%) have active asthma. Average annual prevalence estimates were approximately 45% higher for Black versus White children (12.8% vs. 8.8%), as were average annual estimates of asthma attacks (8.4% vs. 5.8%). Urban minority youth have highly elevated prevalence of poorly controlled asthma as evidenced by overuse of emergency departments and under-use of efficacious medications. Poorly controlled asthma has functional consequences on cognition, connectedness with school, and absenteeism. Exemplary asthma programs include management and support systems, school health and mental health services, asthma education, healthy school environments, physical education and activity, and coordination of school, family, and community efforts.

CONCLUSIONS

Asthma and, more importantly, poorly controlled asthma are highly and disproportionately prevalent among school-aged urban minority youth, has a negative impact on academic achievement through its effects on cognition, school connectedness, and absenteeism, and effective practices are available for schools to address this problem. To reduce the adverse effects of poorly controlled asthma on learning, a multifaceted approach to asthma control and prevention in which schools can and must play a central role is essential.

Obesity is associated with increased asthma severity and exacerbations, and increased serum immunoglobulin E in inner-city adults

BACKGROUND

Obesity is associated with increased asthma and atopy.

OBJECTIVE

To determine whether or not obesity in inner-city adults is associated with increased asthma prevalence, severity and exacerbations and IgE responses.

METHODS

This retrospective study involved 246 adults with asthma and other atopic disorders who were seen at an asthma clinic in New York City between 1997 and 2010. Height, weight, asthma diagnosis and symptoms, peak flow (PF), spirometry, serum IgE levels and white blood cell differentials were recorded.

RESULTS

Asthmatic patients had higher body mass index than non-asthmatics (median, interquartile range: 30.5, 10.2 vs. 27.8, 8.8; Mann-Whitney U-test, P = 0.0006). Class I and II/III obesity were associated with increased asthma (I: OR: 2.35, 95% CI: 1.04-5.34, P = 0.04; II/III: OR: 3.25, 95% CI: 1.36-7.74, P = 0.008). Class I and II/III obesity were associated with worsened asthma severity (ordinal logistic regression; I: OR: 4.23, 95% CI: 1.61-11.06, P = 0.003; II/III: OR: 2.76, 95% CI: 1.08-7.09, P = 0.03). Class II/III obesity was associated with increased asthma exacerbations requiring oral corticosteroids (repeated measures logistic regression, OR: 1.13, 95% CI: 1.03-1.25; P = 0.01) and increased requirement of inhaled corticosteroid for long-term asthma management (OR: 1.45, 95% CI: 1.29-1.62; P < 0.0001). In asthmatics, class II/III obesity was associated with decreased PF (general linear model, least squares mean ± SEM: 333.8 ± 37.4 vs. 396.2 ± 32.1 L/min; P = 0.007), forced expiratory volume in 1 s (75.2 ± 4.6 vs. 88.4 ± 5.6%; P = 0.03) and forced vital capacity (83.2 ± 4.7 vs. 109.2 ± 6.0%; P = 0.0002) and increased serum IgE (480.2 ± 88.3 vs. 269.0 ± 66.6 IU/mL; P = 0.04) and neutrophils (66.6 ± 3.7 vs. 60.1 ± 3.8%; P = 0.02). Class I obesity was also associated with increased serum IgE (458.7 ± 68.9, P = 0.03).

CONCLUSION AND CLINICAL RELEVANCE

Obesity in inner-city adults may be both a risk and exacerbating factor for atopic asthma.

Achieving and maintaining asthma control in inner-city children

BACKGROUND

Despite guidelines-defined care, inner-city children of low socioeconomic status have poor asthma control.

OBJECTIVE

This study evaluated time to achieve control, maintenance of control, and factors associated with well controlled asthma for pediatric patients receiving specialty-based asthma care in mobile asthma clinics designed to reduce barriers to delivering effective asthma care (the Breathmobile Program).

METHODS

Existing clinical data collected from January 1998 to June 2008 for 7822 pediatric patients with asthma (34,339 visits) enrolled in similarly structured mobile asthma programs across the United States evaluated the effect of asthma control on the reduction of asthma-related morbidity, time to achieve asthma control, maintenance of asthma control, and factors associated with well controlled asthma.

RESULTS

Comparison of pre and post year data for subjects enrolled in the program for at least 1 year revealed reductions in the percentage of patients reporting emergency department visits (mean, 66%), hospitalizations (mean, 84%), and missed school days ≥5/year (mean, 78%). Well controlled asthma was achieved by visit 3 for an estimated 80% of patients. Factors contributing to well controlled asthma include non-African American race, visit interval <90 days, and adherence to prescribed therapy.

CONCLUSION

This study demonstrates the ability to achieve and maintain asthma control in high-risk populations in association with intensive, accessible, guidelines-defined care with close follow-up.

Traffic-related particulate matter and acute respiratory symptoms among New York City area adolescents

BACKGROUND

Exposure to traffic-related particulate matter (PM) has been associated with adverse respiratory health outcomes in children. Diesel exhaust particles (DEPs) are a local driver of urban fine PM [aerodynamic diameter < or = 2.5 microm (PM(2.5))]; however, evidence linking ambient DEP exposure to acute respiratory symptoms is relatively sparse, and susceptibilities of urban and asthmatic children are inadequately characterized.

OBJECTIVES

We examined associations of daily ambient black carbon (BC) concentrations, a DEP indicator, with daily respiratory symptoms among asthmatic and nonasthmatic adolescents in New York City (NYC) and a nearby suburban community.

METHODS

BC and PM(2.5) were monitored continuously outside three NYC high schools and one suburban high school for 4-6 weeks, and daily symptom data were obtained from 249 subjects (57 asthmatics, 192 nonasthmatics) using diaries. Associations between pollutants and symptoms were characterized using multilevel generalized linear mixed models, and modification by urban residence and asthma status were examined.

RESULTS

Increases in BC were associated with increased wheeze, shortness of breath, and chest tightness. Multiple lags of nitrogen dioxide (NO(2)) exposure were associated with symptoms. For several symptoms, associations with BC and NO(2) were significantly larger in magnitude among urban subjects and asthmatics compared with suburban subjects and nonasthmatics, respectively. PM(2.5) was not consistently associated with increases in symptoms.

CONCLUSIONS

Acute exposures to traffic-related pollutants such as DEPs and/or NO(2) may contribute to increased respiratory morbidity among adolescents, and urban residents and asthmatics may be at increased risk. The findings provide support for developing additional strategies to reduce diesel emissions further, especially in populations susceptible because of environment or underlying respiratory disease.

Indoor air pollution and asthma in children

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.

Environmental and occupational allergies

Airborne allergens are the major cause of allergic rhinitis and asthma. Daily exposure comes from indoor sources, chiefly at home but occasionally at schools or offices. Seasonal exposure to outdoor allergens, pollens, and molds is another important source. Exposure to unusual substances at work causes occupational asthma, accounting for about 5% of asthma in adults. Indoor and outdoor air pollutants trigger airway inflammation and increase the severity of asthma. Diesel exhaust particles increase the production of IgE antibodies. Identification and reduction of exposure to allergens is a very important part of the management of respiratory allergic diseases. The first section of this chapter discusses domestic allergens, arthropods (mites and cockroaches), molds, and mammals (pets and mice). Indoor humidity and water damage are important factors in the production of mite and mold allergens, and discarded human food items are important sources of proliferation of cockroaches and mice. Means of identifying and reducing exposure are presented. The second section discusses outdoor allergens: pollens and molds. The particular plants or molds and the amount of exposure to these allergens is determined by the local climate, and local pollen and mold counts are available to determine the time and amount of exposure. Climate change is already having an important effect on the distribution and amount of outdoor allergens. The third section discusses indoor and outdoor air pollution and methods that individuals can take to reduce indoor pollution in addition to eliminating cigarette smoking. The fourth section discusses the diagnosis and management of occupational asthma.

Correlation between ERMI values and other moisture and mold assessments of homes in the American Healthy Homes Survey

The main objective of this study was to evaluate the correlation between the Environmental Relative Moldiness Index (ERMI) values in the Department of Housing and Urban Development American Healthy Homes Survey (AHHS) homes and an alternative analysis frequently used in mold investigations, i.e., the inspector's "walk-through" assessment of visual or olfactory evidence of mold combined with occupant's answers to a questionnaire about mold odors and moisture. Homes in the highest ERMI quartile were in agreement with visual inspection and/or occupant assessment 48% of the time but failed to detect the mold in 52% of the fourth quartile homes. In about 7% of lowest ERMI quartile homes, the inspection and occupant assessments overestimated the mold problem. The ERMI analysis of dust from homes may be useful in finding hidden mold problems. An additional objective was to compare the ERMI values in inner city east-Baltimore homes, where childhood asthma is common, to the AHHS randomly selected homes.

Effects of multi-walled carbon nanotubes on a murine allergic airway inflammation model

The development of nanotechnology has increased the risk of exposure to types of particles other than combustion-derived particles in the environment, namely, industrial nanomaterials. On the other hand, patients with bronchial asthma are sensitive to inhaled substances including particulate matters. This study examined the effects of pulmonary exposure to a type of nano-sized carbon nanotube (multi-walled nanotubes: MWCNT) on allergic airway inflammation in vivo and their cellular mechanisms in vitro. In vivo, ICR mice were divided into 4 experimental groups. Vehicle, MWCNT (50 microg/animal), ovalbumin (OVA), and OVA+MWCNT were repeatedly administered intratracheally. Bronchoalveolar lavage (BAL) cellularity, lung histology, levels of cytokines related to allergic inflammation in lung homogenates/BAL fluids (BALFs), and serum immunoglobulin levels were studied. Also, we evaluated the impact of MWCNT (0.1-1 microg/ml) on the phenotype and function of bone marrow-derived dendritic cells (DC) in vitro. MWCNT aggravated allergen-induced airway inflammation characterized by the infiltration of eosinophils, neutrophils, and mononuclear cells in the lung, and an increase in the number of goblet cells in the bronchial epithelium. MWCNT with allergen amplified lung protein levels of Th cytokines and chemokines compared with allergen alone. MWCNT exhibited adjuvant activity for allergen-specific IgG(1) and IgE. MWCNT significantly increased allergen (OVA)-specific syngeneic T-cell proliferation, particularly at a lower concentration in vitro. Taken together, MWCNT can exacerbate murine allergic airway inflammation, at least partly, via the promotion of a Th-dominant milieu. In addition, the exacerbation may be partly through the inappropriate activation of antigen-presenting cells including DC.

Asthma morbidity in adult Chicago public housing residents

BACKGROUND

Residents of public housing can experience socioeconomic disadvantages, inadequate access to health care, and particularly substandard indoor air quality due to inadequate building maintenance.

OBJECTIVE

This study investigates demographic, medical management, severity, and household factors associated with asthma-related emergency department visits and hospitalizations.

METHODS

A total of 103 adult participants with asthma from four Chicago housing developments completed surveys and underwent household inspections.

RESULTS

Using stepwise multivariate logistic regression, we identified independent predictors of asthma-related emergency department visits: asthma controller medication use, not keeping an asthma-related doctor's appointment, and frequent nocturnal wheeze episodes. Using stepwise multivariate logistic regression, we identified independent predictors of asthma-related hospitalizations: peeling paint, plaster, or wallpaper, environmental tobacco smoke, written action plan for an asthma-related doctor or emergency department visit, and frequent nocturnal wheeze episodes.

CONCLUSIONS

In multivariate models, factors related to clinical severity and asthma management were related to both emergency department visits and hospitalizations while household conditions were related only to hospitalizations. Interventions to address both asthma management and household environmental triggers may be needed to reduce asthma morbidity in low-income populations.