Preterm infants with chronic lung disease: are protein and energy intakes after discharge sufficient for optimal growth?

Aim: To document post-discharge feeding practices of preterm infants with chronic lung disease (CLD) and determine if sufficient protein and energy is consumed for optimal growth.

Method: Protein and energy intakes of preterm infants with CLD were quantified through detailed analysis of measured food and fluid intakes at four corrected age (CA) assessments, post-discharge. Most of the infants were in hospital for the term assessment. Milk intake from breastfeeding was determined by test weighing. Protein and energy intakes were compared with the Australian and New Zealand Nutrient Reference Values (NRV) for healthy term-born infants, and CA z-scores for weight, length and head circumference were calculated using Australian national gestational growth data and Centre for Disease Control 2000 growth data.

Results: Ten of the 28 CLD infants who were exclusively receiving expressed breast milk in hospital were transitioned to infant formula within 1 month of discharge. Complementary foods were introduced at a median CA of 3.6 months. Protein intakes almost always exceeded the NRV for healthy term-born infants, and at each assessment, at least 63% of infants met the energy NRV. Longitudinal growth data are available for 20 infants, four of whom had been small for gestational age. At the 12-month assessment, 10 of these infants weighed less than the 10th percentile.

Conclusion: Preterm infants who develop CLD do not always achieve reference growth in their first year following discharge, despite protein and energy intakes being mostly comparable to those recommended for healthy term-born infants.