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ANTIBIOTIC USE EARLY IN LIFE INCREASES RISK FOR ASTHMA

This population-based study confirms previous studies that found an association between antibiotic use and development of childhood asthma.

Results from previous studies have been equivocal regarding the association between antibiotic use early in life and the development of asthma during childhood. To examine risk factors for asthma at age 7, Canadian investigators conducted a longitudinal cohort study using healthcare and prescription databases in Manitoba, Canada.

Among 13,116 children born in 1995, 65% received oral antibiotics during the first year (mostly broad spectrum). To control for reverse causation, children who were diagnosed with asthma during the first year were excluded. After controlling for gender, maternal history of asthma, number of siblings, urban or rural location, and number of healthcare visits, antibiotic use during the first year of life compared with no use was associated with significantly increased risk for developing asthma (odds ratios, 1.27 for 1–2 doses; 1.41 for 3–4 doses; and 1.74 for >4 doses). The association between asthma and antibiotic use was increased among children who lived in rural areas, children whose mothers did not have asthma, and children who did not live with a dog at home during the first year, especially among those who had received multiple doses. The association between asthma and broad-spectrum antibiotic use was statistically significant; the association with narrow-spectrum antibiotics was not. Children who received antibiotics for nonrespiratory infections were about twice as likely to have asthma at age 7 as children who had not …