RESUMEN
RATIONALE: Adverse effects of exposures to ambient air pollution on lung function are well documented, but evidence in racial/ethnic minority children is lacking. OBJECTIVES: To assess the relationship between air pollution and lung function in minority children with asthma and possible modification by global genetic ancestry. METHODS: The study population consisted of 1,449 Latino and 519 African American children with asthma from five different geographical regions in the mainland United States and Puerto Rico. We examined five pollutants (particulate matter ≤10 µm and ≤2.5 µm in diameter, ozone, nitrogen dioxide, and sulfur dioxide), derived from participant residential history and ambient air monitoring data, and assessed over several time windows. We fit generalized additive models for associations between pollutant exposures and lung function parameters and tested for interaction terms between exposures and genetic ancestry. MEASUREMENTS AND MAIN RESULTS: A 5 µg/m(3) increase in average lifetime particulate matter less than or equal to 2.5 µm in diameter exposure was associated with a 7.7% decrease in FEV1 (95% confidence interval = -11.8 to -3.5%) in the overall study population. Global genetic ancestry did not appear to significantly modify these associations, but percent African ancestry was a significant predictor of lung function. CONCLUSIONS: Early-life particulate exposures were associated with reduced lung function in Latino and African American children with asthma. This is the first study to report an association between exposure to particulates and reduced lung function in minority children in which racial/ethnic status was measured by ancestry-informative markers.
Asunto(s)
Contaminación del Aire/efectos adversos , Asma/epidemiología , Negro o Afroamericano/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos , Pulmón/fisiopatología , Grupos Minoritarios/estadística & datos numéricos , Adolescente , Contaminantes Atmosféricos/efectos adversos , Asma/fisiopatología , Niño , Femenino , Humanos , Masculino , Puerto Rico/epidemiología , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Atopy varies by ethnicity, even within Latino groups. This variation might be due to environmental, sociocultural, or genetic factors. OBJECTIVE: We sought to examine risk factors for atopy within a nationwide study of US Latino children with and without asthma. METHODS: Aeroallergen skin test responses were analyzed in 1830 US Latino subjects. Key determinants of atopy included country/region of origin, generation in the United States, acculturation, genetic ancestry, and site to which subjects migrated. Serial multivariate zero-inflated negative binomial regressions stratified by asthma status examined the association of each key determinant variable with the number of positive skin test responses. In addition, the independent effect of each key variable was determined by including all key variables in the final models. RESULTS: In baseline analyses African ancestry was associated with 3 times (95% CI, 1.62-5.57) as many positive skin test responses in asthmatic participants and 3.26 times (95% CI, 1.02-10.39) as many positive skin test responses in control participants. Generation and recruitment site were also associated with atopy in crude models. In final models adjusted for key variables, asthmatic patients of Puerto Rican (exp[ß] [95% CI], 1.31 [1.02-1.69]) and mixed (exp[ß] [95% CI], 1.27 [1.03-1.56]) ethnicity had a greater probability of positive skin test responses compared with Mexican asthmatic patients. Ancestry associations were abrogated by recruitment site but not region of origin. CONCLUSIONS: Puerto Rican ethnicity and mixed origin were associated with degree of atopy within US Latino children with asthma. African ancestry was not associated with degree of atopy after adjusting for recruitment site. Local environment variation, represented by site, was associated with degree of sensitization.
Asunto(s)
Asma/complicaciones , Asma/etnología , Emigración e Inmigración , Interacción Gen-Ambiente , Hispánicos o Latinos/estadística & datos numéricos , Hipersensibilidad Inmediata/etnología , Hipersensibilidad Inmediata/genética , Adolescente , Alérgenos/inmunología , Asma/genética , Asma/inmunología , Población Negra , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/inmunología , Masculino , Prevalencia , Puerto Rico , Factores de Riesgo , Pruebas Cutáneas , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Ethnic-specific interactions between different asthma medications are not well described. OBJECTIVE: To determine whether the use of leukotriene modifiers is associated with the magnitude of bronchodilator responsiveness among Mexican American and Puerto Rican children with persistent asthma. METHODS: A cross-sectional study of 84 Mexican American and 192 Puerto Rican children, with persistent asthma who were aged 8 to 16 years. Within each group, bronchodilator responsiveness to albuterol, objectively assessed via spirometry, was compared between participants using leukotriene modifiers and those not using leukotriene modifiers. RESULTS: Leukotriene modifier use was associated with a clinically significant increase in percentage change in forced expiratory volume in 1 second of 11.8 (P < .001) in Puerto Rican children, but there was no significant change in percentage change in forced expiratory volume in 1 second (-3.2, P=.57) in Mexican American children. This finding persisted after controlling for the use of inhaled corticosteroids. In addition, among the Puerto Rican children, the association between leukotriene modifier use and augmented bronchodilator responsiveness was greatest in those younger than 12 years. CONCLUSIONS: Among children with persistent asthma, use of leukotriene modifiers is associated with augmented bronchodilator responsiveness to albuterol in Puerto Ricans, but not Mexican Americans. This ethnic-specific, drug-drug interaction highlights the need for the further understanding of asthma pharmacogenetics among children from different ethnic groups to improve asthma outcomes.