The use of proton pump inhibitors (PPIs) in children has increased substantially in the past 10 years, but evidence suggests these medications may be associated with the development of asthma. A nationwide cohort study was undertaken to evaluate the association between PPI use and the risk of asthma in children.

Using data from a nationwide registry, the researchers identified children who initiated PPI use during the study period and matched these children with those who didn't. Those with a history of asthma or other chronic diseases were excluded. The final study cohort included 80,870 pairs of PPI initiators and noninitiators (mean age, 12.9 years; 63% girls).

During median follow-up of three years, the risk of asthma was 57% higher among PPI initiators than noninitiators, the incidence rate of asthma being 21.8 per 1,000 person-years and 14 per 1,000 person-years, respectively. The risk was increased in all age groups and highest for infants and children younger than age two. The findings were consistent across individual PPIs, and the risk was similar regardless of the cumulative duration of PPI use. The researchers noted an increased risk of asthma early after PPI initiation, as well as later.