Can infant lung function predict respiratory morbidity during the first year of life in preterm infants?

Abstract

Compared with term-born infants, preterm infants have increased respiratory morbidity in the first year of life. We investigated whether lung function tests performed near term predict subsequent respiratory morbidity during the first year of life and compared this to standard clinical parameters in preterms. The prospective birth cohort included randomly selected preterm infants with and without bronchopulmonary dysplasia. Lung function (tidal breathing and multiple-breath washout) was measured at 44 weeks post-menstrual age during natural sleep. We assessed respiratory morbidity (wheeze, hospitalisation, inhalation and home oxygen therapy) after 1 year using a standardised questionnaire. We first assessed the association between lung function and subsequent respiratory morbidity. Secondly, we compared the predictive power of standard clinical predictors with and without lung function data. In 166 preterm infants, tidal volume, time to peak tidal expiratory flow/expiratory time ratio and respiratory rate were significantly associated with subsequent wheeze. In comparison with standard clinical predictors, lung function did not improve the prediction of later respiratory morbidity in an individual child. Although associated with later wheeze, noninvasive infant lung function shows large physiological variability and does not add to clinically relevant risk prediction for subsequent respiratory morbidity in an individual preterm.

Functional evidence for continued alveolarisation in former preterms at school age?

“…Multivariable regression analysis confirmed the association between Scond and prematurity, showing that gestational age could explain 37% of the variability in Scond independent of other confounders. Lack of association in the multivariable model between other perinatal factors such as BPD, days of supplementary oxygen and intubation with Scond or spirometry after adjusting for gestational age underlines the pathophysiology of new BPD [34]: functional changes are not primarily caused by the therapy (barotrauma or oxygen toxicity), but rather by prematurity per se. However, it remains difficult to disentangle the exact influence of the different interrelating factors, mostly because gestational age and BPD showed strongly collinear effects within our observational study.…”

Respiratory morbidity was an important consequence of prematurity in the first two years after discharge in three cohorts from 1996 to 2009

“…However, it is possible that to identify those infants at highest risk for respiratory morbidity after discharge, the oxygen requirement should be re‐evaluated at 38 or 40 weeks of gestation . Noninvasive lung function testing performed at 44 weeks of gestation has been associated with wheezing at a later age, but could not predict respiratory morbidity during the first year of life . Drysdale et al.…”

Longitudinal assessment of the lung mechanics of very low birth weight preterm infants with and without bronchopulmonary dysplasia

“…There is a need for functional biomarkers for identifying children at risk of subsequent respiratory morbidity. 21 The population of preterm infants and carriers of bronchopulmonary dysplasia is more susceptible to respiratory morbidity, wheezing and development of asthma, according to the literature. 22 Use of lung function tests among these children as a follow-up measure could contribute towards early clinical intervention and improvement of survival.…”