Antibiotic use in infancy and the risk of asthma in Mexican American children.

OBJECTIVE: This study examined the associations of antibiotic use in infancy with lifetime doctor-diagnosed asthma and current wheeze among Mexican American children. METHODS: In a population-based, cross-sectional investigation, parents of 2023 children 4-18 years of age completed a questionnaire/interview addressing respiratory conditions, antibiotic use, and covariates. RESULTS: In adjusted analyses, among children without history of ear infections in infancy, children who used antibiotics ≥3 times and 1-2 times were more likely to report doctor-diagnosed asthma compared with their peers who did not use antibiotics in infancy [adjusted odds ratio (aOR) = 5.14, 95% confidence interval (CI): 2.88-9.17, and aOR = 2.15, 95% CI: 1.26-3.69, respectively, p trend < 0.0001]. The respective aORs for current wheeze were 3.67 (95% CI: 1.95-6.89) and 1.63 (95% CI: 0.91-2.95). Antibiotic use in infancy was not associated with asthma or current wheeze in children who had ear infections in infancy. In additional analyses, antibiotic use in infancy was associated with asthma in children without parental history of asthma or allergies (aOR = 2.73, 95% CI: 1.70-4.39) but not in those with parental history of asthma or allergies. Among Mexico-born participants born in rural areas, antibiotic use in infancy was associated with a seven-fold increase in risk of asthma (aOR = 7.21, 95% CI: 1.46-35.65), while the association was non-significant in Mexico-born children born in urban areas in Mexico. CONCLUSIONS: Antibiotic use in infancy may increase the risk of asthma and wheezing, but these associations were limited to subgroups of children.

Associations of physician-diagnosed asthma with country of residence in the first year of life and other immigration-related factors: Chicago asthma school study.

BACKGROUND: Among Mexican Americans in the United States, US-born children have higher rates of asthma than their Mexico-born peers. OBJECTIVE: To evaluate the associations of immigration-related variables with physician-diagnosed asthma in a sample of Mexican American children. METHODS: We analyzed data from the ongoing Chicago Asthma School Study, a population-based cross-sectional study, for 10,106 Mexican American schoolchildren in Chicago, Illinois. RESULTS: Mexican American children who lived in the United States in the first year of life were more likely to have physician-diagnosed asthma than their peers who lived in Mexico in the first year of life, independent of age, sex, income, language, and country of birth (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.09-2.94). The risk of asthma in US-born children was higher (but not significantly) than that observed in Mexico-born children after accounting for covariates, including country of residence in the first year of life (OR, 1.37; 95% CI, 0.86-2.18). Long-term immigrants (lived in the United States for 10 years) had an increased risk of asthma compared with short-term immigrants (lived in the United States for <10 years), independent of country of residence in the first year of life (OR, 1.93; 95% CI, 1.00-3.73). CONCLUSION: These findings confirm the importance of early childhood exposures and environmental factors that are modified with migration and acculturation in asthma development.

Associations of acculturation and country of birth with asthma and wheezing in Mexican American youths.

BACKGROUND: Mexican Americans have lower rates of asthma than other ethnic groups in the United States. OBJECTIVE: To examine the relationship between country of birth and acculturation with asthma and wheezing among Mexican American youths. METHODS: We used Chi-squared statistics and logistic regression analyses to determine the associations of country of birth and acculturation with asthma and wheezing among 1,770 Mexican Americans age 12-19 years who participated in the National Health and Nutrition Examination Survey 1999-2002. RESULTS: Mexican American adolescents born in the United States and those with high acculturation levels reported significantly higher prevalence rates of asthma, wheezing, and hay fever than their peers with low acculturation levels and born in Mexico. In multivariate analyses, youths with a high acculturation level had a higher risk of asthma than those with a low acculturation level independent of country of birth. Highly acculturated youths born in the US had a higher risk for wheezing compared with less acculturated US-born or Mexico-born participants after adjusting for confounding variables. In contrast, associations of asthma and wheezing with country of birth were not significant after controlling for acculturation. CONCLUSIONS. Our findings showed that both acculturation and country of birth were linked with the risk of asthma and wheezing, with acculturation having stronger effects than country of birth, among Mexican American youths. These findings may imply that factors modified by immigration and acculturation could influence the risk of asthma and wheezing. Identification of such factors could help in the design of asthma prevention programs.