Severe bronchiolitis in infancy tied to reduced lung function in childhood

Infants with severe bronchiolitis are at heightened risk of having decreased lung function at age 6 years, according to a study.

The study included data from two prospective cohort studies. The first cohort involved infants hospitalized with bronchiolitis, while the second consisted of healthy infants. These children were followed longitudinally, with spirometry performed at age 6 years.

Spirometry data were available for 425 children with severe bronchiolitis in infancy and 48 who did not (control). Unadjusted linear regression models showed that lung function was in the normal range for most of the children. However, those with a history of severe bronchiolitis in infancy had significantly lower forced expiratory volume in 1 second (FEV1) percent predicted and FEV1/forced vital capacity (FVC) percent predicted.

The association of severe bronchiolitis in infancy with lower FEV1 percent predicted and FEV1/FVC percent predicted persisted in an analysis adjusted for potential confounders (ie, insurance status, preterm birth, secondhand smoke exposure, breastfeeding status, traffic-related air pollution and polygenic risk score).

Compared with controls, children with severe bronchiolitis in infancy had 8-percent lower FEV1 percent predicted (p=0.004) and 4-percent lower FEV1/FVC percent predicted (p=0.007).

The findings suggest that children with a history of severe bronchiolitis in infancy may be susceptible to chronic respiratory illness later in life.