Blood fatty acid changes in preterm infants in a trial of enteral DHA supplementation.

BACKGROUND: Very preterm infants miss the peak in-utero supply of omega-3 docosahexaenoic acid (DHA) and omega-6 arachidonic acid (AA), and are thought to receive low amounts after birth. METHODS: In a randomized controlled trial of 1077 babies born <29 weeks' gestation we assessed the DHA and AA concentrations in whole blood before and after (36 weeks' post menstrual age, PMA) enteral emulsion intervention with 60 mg/kg/d of DHA compared with no DHA soy oil. RESULTS: Prior to the intervention, all infants had similar mean DHA (2.8% of total fatty acids) and mean AA (intervention 10.45%; control 10.42%) concentrations. By 36 weeks', mean DHA of intervention group infants increased to 3.86%, while it decreased to 2.53% in the control group (mean difference 1.33%, 95% CI 1.27 to 1.40, p < 0.0001). AA was lower at 36 weeks' than at enrolment, with the decrease marginally more pronounced in the intervention group (8.11%) compared with the control group (8.84%, mean difference -0.71%, 95% CI -0.86 to -0.57, p < 0.0001). CONCLUSION: All fatty acids regressed towards a new diet-dependent mean at 36 weeks regardless of the initial level. DHA supplementation successfully prevented the typical decline in DHA and modestly exacerbated the decline in AA. TRIAL REGISTRATION: The N3RO Trial is registered at the Australian New Zealand Clinical Trial Registry as ACTRN12612000503820 (anzctr.org.au), 9 May 2012. IMPACT: High-dose DHA supplementation in preterm infants prevents the typical postnatal decline in DHA. This study provides evidence from over 1000 infants across Australia, New Zealand, and Singapore. The findings have direct implications for optimizing neonatal nutrition in very preterm populations.