The role of nutrition in promoting growth in pre-term infants with bronchopulmonary dysplasia: a prospective non-randomised interventional cohort study

Background: Pre-term infants who develop bronchopulmonary dysplasia (BPD) are at risk of postnatal growth failure. It has been reported that energy expenditure is higher in infants with BPD than in those without BPD. The aim of the study was to evaluate whether increasing the enteral energy intake of pre-term infants with BPD can improve post-natal growth.Methods: This prospective, non-randomised interventional cohort study was designed to assess growth in 57 preterm infants with BPD (gestational age <32 weeks, birth weight <1500 g, and persistent oxygen dependency for up to 28 days of life) fed individually tailored fortified breast milk and/or preterm formula, and a historical control group of 73 pre-term infants with BPD fed breast milk fortified in accordance with the instructions of the manufacturer and/or pre-term formula. Between-group differences in the continuous variables were analysed using Student's t test or the Mann-Whitney test; the discrete variables were compared using the chi-squared test. Linear regression analysis was used to investigate the independent contribution of enteral energy intake to weight gain velocity.Results: The duration of parenteral nutrition was similar in the historical and intervention groups (43.7 ± 30.9 vs 39.6 ± 17.4 days). After the withdrawal of parenteral nutrition, enteral energy intake was higher in the infants in the intervention group with mild or moderate BPD (131 ± 6.3 vs 111 ± 4.6 kcal/kg/day; p < 0.0001) and in those with severe BPD (126 ± 5.3 vs 105 ± 5.1 kcal/kg/day; p < 0.0001), whereas enteral protein intake was similar (3.2 ± 0.27 vs 3.1 ± 0.23 g/kg/day).Weight gain velocity was greater in the infants in the intervention group with mild or moderate BPD (14.7 ± 1.38 vs 11.5 ± 2 g/kg/day, p < 0.0001) and in those with severe BPD (11.9 ± 2.9 vs 8.9 ± 2.3 g/kg/day; p < 0.007). The percentage of infants with post-natal growth retardation at 36 weeks of gestational age was higher in the historical group (75.3 vs 47.4; p = 0.02).Conclusions: On the basis of the above findings, it seems that improved nutritional management promotes post-natal ponderal growth in pre-term infants with BPD.