Lung function deficits and bronchodilator responsiveness at 12 years of age in children born very preterm compared with controls born at term

Abstract

IntroductionVery preterm birth is associated with lung function impairment later in life, but several aspects have not been studied. We aimed to comprehensively assess lung function at school age in very preterm infants and term controls, with special emphasis on bronchopulmonary dysplasia (BPD), sex, and bronchodilator response.MethodsAt 12 years of age, 136 children born very preterm (85 with and 51 without BPD) and 56 children born at term performed spirometry, body plethysmography, impulse oscillometry, measurement of diffusion capacity, and multiple breath washout, before and after bronchodilator inhalation.ResultsAirway symptoms and a diagnosis of asthma were more common in children born very preterm. These children had more airflow limitation, seen as lower forced expiratory volume in 1 s (FEV1) (p < .001), FEV1/forced vital capacity (FVC) (p = .011), and mean forced expiratory flow between 25% and 75% of FVC (p < .001), and a higher total and peripheral airway resistance compared with term‐born controls. There was no difference in total lung capacity but air trapping and lung clearance index were higher in children born very preterm. Diffusion capacity was lower in children born very preterm, especially in those with a diagnosis of BPD. In most other tests, the differences between preterm‐born children with or without BPD were smaller than between children born preterm versus at term. Boys born preterm had more lung function deficits than preterm‐born girls. In children born very preterm, airway obstruction was to a large extent reversible.ConclusionAt 12 years of age, children born very preterm had lower lung function than children born at term in most aspects and there was only little difference between children with or without BPD. Airway obstruction improved markedly after bronchodilator inhalation.

Inflammatory imbalance in tracheal aspirate of very preterm newborns is associated with airway obstruction and lung function deficiencies at school age: a cohort study

“… 25–27 Data are presented as per cent of predicted (median and IQR) and as proportion of children outside of normal limits: upper (ULN) and lower (LLN) limit of normal. For impulse oscillometry, airway resistance by body plethysmography, and MBW, normal values were defined from our previous study 28 (see online supplemental file 1 ). In the tables, measurements are reported as absolute values, per cent of predicted normal values (FEV 1 ), z-scores or number of individuals <LLN, >ULN, <5th centile and >95th centile.…”

Long-term pulmonary outcomes of young adults born prematurely: a Polish prospective cohort study PREMATURITAS 20

“…In addition to the spirometric parameters, lung clearance index (LCI), a marker of ventilation inhomogeneity derived from multiple breath washout (MBW), start to be applied in preterm subjects [ 7 ]. In certain studies, LCI was found to be higher in children born very preterm [ 8 ]. Nevertheless, further research is required, particularly among young survivors.…”

Evolving treatment for prematurity-associated lung disease

“…There is an increasing concern that PLD may predispose an individual to the premature development of chronic obstructive pulmonary disease (COPD) in early adulthood ( 7 , 8 ), with implications for quality of life and life expectancy if lung function deficits continue to track into adulthood. Whilst much research focus has concentrated on the mechanism of respiratory morbidity in those with a history of BPD ( 9 , 10 ), it is increasingly apparent that there is a population of preterm-born subjects who develop PLD despite not having had a diagnosis of BPD in the neonatal period ( 3 , 11 ), with impaired spirometry, altered respiratory mechanics and reduced gas diffusion capacity ( 12 ). Furthermore, other early life risk factors such as gestational immaturity and intrauterine growth restriction are also strongly associated with later adverse respiratory outcomes ( 13 ).…”

“…Whilst it is well documented that preterm-born subjects generally respond well to short-acting β 2 -agonists, including those with and without a neonatal diagnosis of BPD ( 12 , 23 ), the Pelkonen study assessed two-week course of daily terbutaline administration. Although they did not report post-treatment lung function, they suggested improved diurnal variation of PEFR ( 20 ).…”