Abstract
Childhood asthma is a complex disease likely resulting from an interaction of genetic and environmental causes. The indoor environment, where young children spend most of their time, is suspected to be important in disease development. Asthma prevalence and severity are high for children in inner-cities of the US, but asthma development in this setting is not well studied. This study examined the association between exposure to indoor environmental agents and wheezing and eczema in the first year of life among a cohort of 103 infants in low-income areas of Syracuse, NY. The relationship between household conditions and indoor environmental agents was investigated. Homes were inspected and samples were taken for a variety of indoor pollutants. Household dust was collected for measurement of indoor allergen and endotoxin concentrations. Infant health was evaluated at quarterly home visits and through medical record review. Wheeze was observed in 38% and eczema in 35% of infants. High concentrations of endotoxin and elevated concentrations of dust mite in the baby's bed were each associated with an increased risk of wheeze in unadjusted analyses, but not after adjustment for other risk factors. Multivariable logistic regression showed that exposure to cat allergen was associated with a reduced risk of eczema. Other independent risk factors were significantly and inversely related to eczema including household smoking, musty odors, spring season of birth and the airborne fungus Alternaria. Dust mite allergen in the baby's bed was significantly and inversely associated with eczema in unadjusted analysis, but not in adjusted models. Other allergens including dog and cockroach were not associated with eczema or wheeze. No indoor pollutants were found to increase the risk of eczema. Endotoxin levels were comparable to those reported from other US studies. Multiple linear regression showed that fall season of sampling, relative humidity, housekeeping issues, Black race or Hispanic ethnicity and a resident dog were significant predictors of endotoxin. Exposure to cockroach, dog and cat allergen was common while exposure to dust mite allergen was rare. Important predictors of cockroach allergen included observed or reported cockroaches, household smoking and water problems in the home.