TOPLINE

Among children born very preterm, nearly one third had abnormal pulmonary findings at preschool age compared with peers with normal spirometry, and these children had higher rates of positive bronchodilator responses, recurrent respiratory infections, asthma medication use, and a family history of atopy.

METHODOLOGY

• Researchers conducted a retrospective cohort study to evaluate lung function, bronchodilator responsiveness, and factors associated with abnormal spirometry in preschool-aged children born very preterm.
• They included 107 children (median age, 5.1 years; 59.8% boys) who were born before 32 weeks of gestation or had a birth weight below 1500 g and admitted to the NICU in Austria between 2016 and 2019.
• Participants underwent spirometry before and after bronchodilator administration to assess bronchodilator responsiveness; a positive bronchodilator response was defined as an increase in forced expiratory volume in 1 second (FEV₁) of at least 12% from baseline.
• At preschool follow-up, participants were classified into two groups: a pathologic group with abnormal pulmonary findings identified primarily by spirometry and a normal group with normal pulmonary function and no clinically relevant respiratory symptoms.

TAKEAWAY

• Among children who completed spirometry successfully, 31.2% were classified as the pathologic group; these children showed significantly greater bronchodilator responsiveness (median change in FEV₁, 14.9% vs 4.9%) and a higher rate of positive bronchodilator response (44.8% vs 15.6%) than those in the normal group (P < .001 for both).
• The pathologic group had significantly lower median forced vital capacity (79.9% vs 94.8%) and FEV₁ (77.3% predicted vs 95.5% predicted), as well as lower peak expiratory flow and mid-expiratory flow measures, than the normal group (P < .001 for all).
• Children in the pathologic group required a longer duration of invasive mechanical ventilation (81.6 vs 23.0 hours) and more frequently received postnatal glucocorticoid therapy (24.1% vs 7.8%) than those in the normal group (P < .05 for both).
• Moreover, children in the pathologic group were more likely to have a family history of atopy (55.2% vs 25.0%) and recurrent respiratory infections (65.5% vs 18.8%) and more frequently used asthma medication (58.6% vs 34.4%) than those in the normal group (P < .05 for all).

IN PRACTICE

"Our study emphasizes that respiratory vulnerability persists into preschool age in a substantial proportion of preterm-born children," the authors wrote. "Early lung function testing at preschool age may therefore provide a clinically relevant opportunity to identify high-risk children and initiate preventive strategies before lifestyle factors, such as active smoking, become confounding," they added.

SOURCE

This study was led by Michaela Höck, Medical University of Innsbruck, Innsbruck, Austria. It was published online on August 05, 2026, in Frontiers in Pediatrics.

LIMITATIONS

The study excluded children unable to perform reliable spirometry, potentially underestimating respiratory impairment. Exploratory subgroup analyses were based on a modest sample size and remained susceptible to residual confounding. The lack of body plethysmography prevented reliable differentiation between true restrictive impairment and pseudo-restriction.

DISCLOSURES

The study did not receive any specific funding. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.