Improved lung function at age 6 in children born very preterm and fed extra protein post-discharge.

Background: In very preterm-born children, alveolar maturation is challenged and lung function is often compromised during childhood. So far, very few studies have focused on type of early nutrition and lung function in children born preterm.

Methods: This study is a 6 years follow-up of 281 very preterm-born infants (VPI) with a gestational age (GA) <32 + 0 weeks. Infants breastfed at discharge from hospital were randomized to unfortified (UHM) or fortified (FHM) mother's (human) milk, whereas those not breastfed received a preterm formula (PF). The intervention lasted until 4 months corrected age. At 6 years of age fractional exhaled nitric oxide (FeNO), airway resistance and occlusion measurements with reversibility were performed. Data on predisposition to asthma and allergy as well as possible allergic symptoms of the child were obtained with questionnaires.

Results: Outcome data was fully or partially available on 160 (66.9%) of 239 children. This included 49 (30.6%) children fed UHM, 58 (36.3%) fed FHM and 53 (33.1%) fed PF. Successful FeNO measurements were obtained in 119 (74.4%) children and airway resistance measurements in 160. FeNO results were not significantly different between feeding groups. Children fed a protein-enriched diet (FMH/PF) had the lowest, for example, best, airway resistance; FHM-fed had lower values than UHM-fed (P = 0.042) before, and PF-fed had significantly lower values than UHM-fed after beta-2-agonist inhalation (P = 0.050). The tendency of lower airway resistance when protein enriched were the same in gender-specific analyses. In SGA children, the same tendency was found between PF- and UHM-fed (P = 0.007 before and P = 0.046 after beta-2-agonist inhalation). All values were within reference limits.

Conclusions: Lung function in very preterm-born children may improve when fed a protein-enriched nutrition post-discharge.