Antibiotics in infancy may increase asthma risk

HealthDay News — There was a small increase in the number of asthma diagnoses in patients who were prescribed antibiotics during their first 12 months, according to study findings in The Lancet Respiratory Medicine.

Aida Semic-Jusufagic, MD, and colleagues followed 916 patients from birth cohort through 11 years of age and used medical records to determine atopy, wheeze, and asthma exacerbations in relation to early life antibiotic prescription. They also assessed the effect of genetic variants on asthma susceptibility locus 17q21 on these relationships.

Immune responses of peripheral blood mononuclear cells to viruses (rhinovirus and respiratory syncytial virus) and bacteria (Haemophilus influenzae and Streptococcus pneumoniae) were assessed from samples taken at 11 years of age.

There was a higher risk of physician-confirmed wheezing (hazard ratio, 1.71; P<0.0001) and severe wheeze or asthma exacerbation (HR, 2.26; P=0.041) among patients who were prescribed an antibiotic in infancy, the researchers found.

The likelihood of exacerbation (HR, 2.09; P<0.0001) and admissions to the hospital (HR, 2.64; P=0.0009) were significantly increased in the two years after the first antibiotic prescription in children who wheezed.

There was a significantly lower induction of cytokines, important in host defense virus infections to both RSV and rhinovirus, among children who received antibiotics in infancy.

“The association between antibiotics and asthma might arise through a complex confounding by indication,” wrote the researchers. “Hidden factors that may increase the likelihood of both early life antibiotic prescription and later asthma are an increased susceptibility to viral infections consequent upon impaired antiviral immunity and genetic variants on 17q21.”