The use of antibiotics during infancy might contribute to the rising prevalence of childhood asthma. These effects may arise on the composition of the intestinal microbiota. 62,576 US children enrolled from birth through age 5 from 1999 through 2006 were reviewed for antibiotic exposure during the first year of life and the development of three asthma phenotypes. These included transient wheezing, late-onset asthma (starting after 3 years), and persistent asthma (starting by 3 years and continuing 4- 7 years).
Children exposed to antibiotics were more likely to develop transient wheezing, odds ratio (OR) 2.0, and persistent asthma OR 1.6. There was a significant dose-response effect in children receiving at least 5 courses of antibiotics, OR ratio of 2. This analysis suggests that antibiotic exposure during the first year of life is associated with increased risk of asthma during the first 3 years of life.
Almost 20% of children developed wheezing or asthma between infancy and 7 years. With each course of antibiotic exposure, there was an increased risk of developing asthma. There was also a significant association between early-life upper respiratory infections and each type of asthma phenotype. This study is another warning about the importance of judicious use of antibiotics in children