Dataset Information

School Endotoxin Exposure and Asthma Morbidity in Inner-city Children.

ABSTRACT: Endotoxin exposure is associated with airway inflammation. Children spend 6 to 8 h/d in school, yet the effect of school-specific endotoxin exposure on asthma morbidity is not well understood.In this longitudinal cohort study, 248 students with asthma, from 38 inner-city schools, underwent baseline phenotyping and follow-up. Clinical outcomes were evaluated throughout the academic school year and linked to classroom-specific dust and air endotoxin levels as well as home dust endotoxin levels. The primary outcome was maximum asthma symptom-days per 2-week period.Classrooms had higher settled dust endotoxin levels compared with homes (14.3 endotoxin unit/mg vs 11.3 endotoxin unit/mg; P = .02). Airborne endotoxin levels exceeding recommended occupational exposure limits for adults were recorded in 22.0% of classrooms. Classroom air endotoxin levels were independently associated with increased maximum symptom-days in children with nonatopic asthma, but not in those with atopic asthma (interaction P = .03). Adjusting for home exposures, classroom endotoxin exposure was independently associated with a dose-dependent increase in asthma symptom-days for children with nonatopic asthma (adjusted incidence rate ratio, 1.16 [95% CI, 1.03-1.31]; P = .02). In these subjects, maximum symptom-days increased by 1.3 days for each 14-day period when comparing students in classrooms with the lowest endotoxin levels compared with average measured levels.Inner-city children with asthma are exposed to high levels of airborne endotoxin at school, resulting in increased asthma symptoms in children with nonatopic asthma. Mitigation of school-related exposures may represent a strategy to decrease asthma morbidity in this population.ClinicalTrials.gov; No.: NCT01756391; URL: www.clinicaltrials.gov.

SUBMITTER: Lai PS

PROVIDER: S-EPMC4631040 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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School Endotoxin Exposure and Asthma Morbidity in Inner-city Children.

Lai Peggy S PS Sheehan William J WJ Gaffin Jonathan M JM Petty Carter R CR Coull Brent A BA Gold Diane R DR Phipatanakul Wanda W

Chest 20151101 5

<h4>Background</h4>Endotoxin exposure is associated with airway inflammation. Children spend 6 to 8 h/d in school, yet the effect of school-specific endotoxin exposure on asthma morbidity is not well understood.<h4>Methods</h4>In this longitudinal cohort study, 248 students with asthma, from 38 inner-city schools, underwent baseline phenotyping and follow-up. Clinical outcomes were evaluated throughout the academic school year and linked to classroom-specific dust and air endotoxin levels as wel ...[more]

PMID: 26087201

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Project description:To examine the association of social and environmental factors with levels of second-hand smoke (SHS) exposure, as measured by salivary cotinine, in young inner-city children with asthma.We used data drawn from a home-based behavioral intervention for young high-risk children with persistent asthma post-emergency department (ED) treatment (N = 198). SHS exposure was measured by salivary cotinine and caregiver reports. Caregiver demographic and psychological functioning, household smoking behavior, and asthma morbidity were compared with child cotinine concentrations. Chi-square and ANOVA tests and multivariate regression models were used to determine the association of cotinine concentrations with household smoking behavior and asthma morbidity.Over half (53%) of the children had cotinine levels compatible with SHS exposure and mean cotinine concentrations were high at 2.42 ng/ml (SD 3.2). The caregiver was the predominant smoker in the home (57%) and 63% reported a total home smoking ban. Preschool aged children and those with caregivers reporting depressive symptoms and high stress had higher cotinine concentrations than their counterparts. Among children living in a home with a total home smoking ban, younger children had significantly higher mean cotinine concentrations than older children (cotinine: 3-5 year olds, 2.24 ng/ml (SD 3.5); 6-10 year olds, 0.63 ng/ml (SD 1.0); p < .05). In multivariate models, the factors most strongly associated with high child cotinine concentrations were increased number of household smokers (? = 0.24) and younger child age (3-5 years) (? = 0.23; p < .001, R(2) = 0.35).Over half of the young inner-city children with asthma were exposed to SHS, and caregivers are the predominant household smokers. Younger children and children with depressed and stressed caregivers are at significant risk of smoke exposures, even when a household smoking ban is reported. Further advocacy for these high-risk children is needed to help caregivers quit and to mitigate smoke exposure.

Dataset Information

School Endotoxin Exposure and Asthma Morbidity in Inner-city Children.

Publications

School Endotoxin Exposure and Asthma Morbidity in Inner-city Children.

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