Enteral supplementation with arachidonic and docosahexaenoic acid and pulmonary outcome in extremely preterm infants.

Enteral supplementation with arachidonic acid (AA) and docosahexaenoic acid (DHA) in extremely preterm infants has shown beneficial effects on retinopathy of prematurity and pulmonary outcome whereas exclusive DHA supplementation has been associated with increased pulmonary morbidity. This secondary analysis evaluates pulmonary outcome in 204 extremely preterm infants, randomized to receive AA (100 mg/kg/day) and DHA (50 mg/kg/day) enterally from birth until term age or standard care. Pulmonary morbidity was primarily assessed based on severity of bronchopulmonary dysplasia (BPD). Serum levels of AA and DHA during the first 28 days were analysed in relation to BPD. Supplementation with AA:DHA was not associated with increased BPD severity, adjusted OR 1.48 (95 % CI 0.85-2.61), nor with increased need for respiratory support at post menstrual age 36 weeks or duration of oxygen supplementation. Every 1 % increase in AA was associated with a reduction of BPD severity, adjusted OR 0.73 (95 % CI 0.58-0.92). In conclusion, in this study, with limited statistical power, enteral supplementation with AA:DHA was not associated with an increased risk of pulmonary morbidity, but higher levels of AA were associated with less severe BPD. Whether AA or the combination of AA and DHA have beneficial roles in the immature lung needs further research.

Inflammatory imbalance in tracheal aspirate of very preterm newborns is associated with airway obstruction and lung function deficiencies at school age: a cohort study.

OBJECTIVE: A low expression of club cell secretory protein (CC16) and high levels of proinflammatory cytokines at preterm birth are associated with airway inflammation and more severe neonatal lung disease. The present study aimed to investigate if low levels of CC16, proinflammatory cytokines and vascular endothelial growth factors (VEGF) in tracheal aspirate early after birth were associated with lung function impairment at school age. PATIENTS AND METHODS: Participants were 20 children, born very preterm (median gestational age 25+3 weeks+days, IQR: 24+1-27+0 weeks+days), who had tracheal aspirates collected during mechanical ventilation in their first day of life. CC16, cytokines, VEGF and matrix metalloproteinase-9 were measured in the tracheal aspirate and later correlated to results from advanced lung function measurements at 12 years of age. RESULTS: Low levels of CC16 and high levels of the proinflammatory cytokines IL-1ß and TNF-α in tracheal aspirate were associated with airway obstruction at school age but not with other lung function parameters. The correlation with airway obstruction was even stronger when the ratio between the respective proinflammatory cytokine and CC16 was used. In addition, low levels of VEGF and CC16 were associated with impaired diffusion capacity of the lung. CONCLUSIONS: An imbalance in inflammatory mediators and growth factors in the lungs at birth may have consequences for airway function and vasculature at school age in preterm born children.

Arachidonic acid and docosahexaenoic acid levels correlate with the inflammation proteome in extremely preterm infants.

BACKGROUND & AIM: Clinical trials supplementing the long-chain polyunsaturated fatty acids (LCPUFAs) docosahexaenoic acid (DHA) and arachidonic acid (AA) to preterm infants have shown positive effects on inflammation-related morbidities, but the molecular mechanisms underlying these effects are not fully elucidated. This study aimed to determine associations between DHA, AA, and inflammation-related proteins during the neonatal period in extremely preterm infants. METHODS: A retrospective exploratory study of infants (n = 183) born below 28 weeks gestation from the Mega Donna Mega trial, a randomized multicenter trial designed to study the effect of DHA and AA on retinopathy of prematurity. Serial serum samples were collected after birth until postnatal day 100 (median 7 samples per infant) and analyzed for phospholipid fatty acids and proteins using targeted proteomics covering 538 proteins. Associations over time between LCPUFAs and proteins were explored using mixed effect modeling with splines, including an interaction term for time, and adjusted for gestational age, sex, and center. RESULTS: On postnatal day one, 55 proteins correlated with DHA levels and 10 proteins with AA levels. Five proteins were related to both fatty acids, all with a positive correlation. Over the first 100 days after birth, we identified 57 proteins to be associated with DHA and/or AA. Of these proteins, 41 (72%) related to inflammation. Thirty-eight proteins were associated with both fatty acids and the overall direction of association did not differ between DHA and AA, indicating that both LCPUFAs similarly contribute to up- and down-regulation of the preterm neonate inflammatory proteome. Primary examples of this were the inflammation-modulating cytokines IL-6 and CCL7, both being negatively related to levels of DHA and AA in the postnatal period. CONCLUSIONS: This study supports postnatal non-antagonistic and potentially synergistic effects of DHA and AA on the inflammation proteome in preterm infants, indicating that supplementation with both fatty acids may contribute to limiting the disease burden in this vulnerable population. CLINICAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03201588).