Geographic variability in childhood asthma prevalence in Chicago.

BACKGROUND Childhood asthma prevalence has been shown to be higher in urban communities overall without an understanding of differences by neighborhood. OBJECTIVE To characterize the geographic variability of childhood asthma prevalence among neighborhoods in Chicago. METHODS Asthma screening was conducted among children attending 105 Chicago schools as part of the Chicago Initiative to Raise Asthma Health Equity. Additional child information included age, sex, race/ethnicity, and household members with asthma. Surveys were geocoded and linked with neighborhoods. Neighborhood information on race, education, and income was based on 2000 census data. Bivariate and multilevel analyses were performed. RESULTS Of the 48,917 surveys, 41,255 (84.3%) were geocoded into 287 neighborhoods. Asthma prevalence among all children was 12.9%. Asthma rates varied among neighborhoods from 0% to 44% (interquartile range, 8% to 24%). Asthma prevalence (mean, SD, range) in predominantly black neighborhoods (19.9, +/-7, 4% to 44%) was higher than in predominantly white neighborhoods (11.4, +/-4.7, 2% to 30%) and predominantly Hispanic neighborhoods (12.1, +/-6.8, 0% to 29%). Although sex, age, household members with asthma, and neighborhood income significantly affected asthma prevalence, they did not explain the differences seen between neighborhoods. Race explained a significant proportion (about 80%) but not all of this variation. CONCLUSION Childhood asthma prevalence varies widely by neighborhood within this urban environment. Adjacent areas in Chicago were identified with significantly different asthma prevalence. A better understanding of the effect of neighborhood characteristics may lend insight into potential interventions to reduce childhood asthma.