Lung function trajectories in children with post-prematurity respiratory disease: identifying risk factors for...

Survivors of prematurity are at risk for abnormal childhood lung function. Few studies have addressed trajectories of lung function and risk factors for abnormal growth in childhood. This study aims to describe changes in lung function in a contemporary cohort of children born preterm followed longitudinally in pulmonary clinic for post-prematurity respiratory disease and to assess maternal and neonatal risk factors associated with decreased lung function trajectories.

Observational cohort of 164 children born preterm ≤ 32 weeks gestation followed in pulmonary clinic at Boston Children's Hospital with pulmonary function testing. We collected demographics and neonatal history. We used multivariable linear regression to identify the impact of neonatal and maternal risk factors on lung function trajectories in childhood.

We identified 264 studies from 82 subjects with acceptable longitudinal FEV₁ data and 138 studies from 47 subjects with acceptable longitudinal FVC and FEV₁/FVC data. FEV₁% predicted and FEV₁/FVC were reduced compared to childhood norms. Growth in FVC outpaced FEV₁, resulting in an FEV₁/FVC that declined over time. In multivariable analyses, longer duration of mechanical ventilation was associated with a lower rate of rise in FEV₁% predicted and greater decline in FEV₁/FVC, and postnatal steroid exposure in the NICU was associated with a lower rate of rise in FEV₁ and FVC % predicted. Maternal atopy and asthma were associated with a lower rate of rise in FEV₁% predicted.

Children with post-prematurity respiratory disease demonstrate worsening obstruction in lung function throughout childhood. Neonatal risk factors including exposure to mechanical ventilation and postnatal steroids, as well as maternal atopy and asthma, were associated with diminished rate of rise in lung function. These results may have implications for lung function trajectories into adulthood.