Early postnatal weight evolution and the development of bronchopulmonary dysplasia

Abstract

Background: Bronchopulmonary dysplasia (BPD) remains a common complication of preterm birth. Recently, there has been a renewed interest in early postnatal weight evolution (EPWE) as a predictor for BPD development, but its exact role remains controversial. Aim: The aim of this study is to further investigate the role of EPWE in BPD development. Methods: We included 131 extremely preterm infants (gestational age Results: Median gestational age was 26.14 weeks and median birth weight 820g. The majority (70.2%) of infants developed BPD (49.6% mild, 8.4% moderate, 8.4% severe and 3.8% unclassified BPD; 9.2%no BPD). The mortality rate was 20.6%. Infants who developed BPD had significantly lower birth weights, but by day 7 and 14 the weight differences were no longer significant, indicating a different weight evolution. By day 14, BPD infants had gained significantly more weight (i.e.percentage weight gain relative to birth weight; p=0.01; median 0.80% vs 7.57% in the BPD group). Interestingly, logistic regression identified weight gain at day 14 as a predictor of BPD development (p=0.02; OR=1.11;CI[1.01;1.22]). Relative maximal weight loss in the first 2 weeks of life was not different between patients with and without BPD. Conclusion: Relative weight gain during the first two weeks of life is a significant predictor of BPD development in our study. The underlying pathophysiological mechanism may involve fluid retention with impaired oxygenation and higher need for oxygen therapy but could also be linked to differences in nutritional support.