Published Online: November 11, 2015
Children born at a younger gestational age or with a smaller size at birth are at increased risk for respiratory diseases in later life, including childhood asthma. The underlying mechanisms are not fully known.
In a recent article published in The Journal of Allergy and Clinical Immunology (JACI), Den Dekker and colleagues hypothesized that associations of gestational age and weight at birth, and weight gain in the first 12 months of life with childhood asthma might be explained by developmental adaptations of the lungs and airways in early life, leading to relatively small airways. Smaller airways could result in increased airway obstruction, which can be measured by lung function tests, that predisposes individuals to asthma. To assess this hypothesis, the authors used original data of almost 25,000 children participating in 24 European birth cohorts. All children had been followed up from birth until a mean age of 8 years, with the oldest child being 18 years of age.
The authors observed that children being born with a younger gestational age or lower birthweight or who had a lower infant weight gain had adaptations in childhood lung function. These associations were present across the full spectrum of these early growth characteristics. Children born very preterm with a relatively low birthweight had the lowest lung function measures. Furthermore, the observed lung function adaptations seem to explain to a substantial extent (7-45%) the risk of childhood asthma.
This study indicates that growth characteristics at birth and in infancy could persistently affect lung function, and thereby contributes to the risk of respiratory diseases later in life. These findings could be used for developing prevention programs to optimize the early phase of life to prevent respiratory diseases at the long term.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.