Feeding preterm infants milk with a higher dose of docosahexaenoic acid than that used in current practice does not influence language or behavior in early childhood: a follow-up study of a randomized controlled trial.

BACKGROUND The visual and mental development of preterm infants improved after feeding them milk enriched with docosahexaenoic acid (DHA) in amounts matching the fetal accretion rate. OBJECTIVE The objective was to evaluate whether feeding preterm infants milk with a higher DHA content than that used in current practice influences language or behavior in early childhood. DESIGN This was a follow-up study in a subgroup of infants enrolled in the DINO (Docosahexaenoic acid for the Improvement in Neurodevelopmental Outcome) trial. In a double-blind randomized controlled trial, infants born at <33 wk of gestation were fed milk containing 1% of total fatty acids as DHA (higher-DHA group) or approximately 0.3% DHA (control group) until reaching full-term equivalent age. The longer-term effects of the intervention on language, behavior, and temperament were measured by using the MacArthur Communicative Development Inventory (MCDI) at 26-mo corrected age, the Strengths and Difficulties Questionnaire (SDQ), and the Short Temperament Scale for Children (STSC) between 3- and 5-y corrected age. RESULTS Mean (+/-SD) MCDI scores did not differ significantly (adjusted P = 0.8) between the higher-DHA group (308 +/- 179, n = 60) and the control group (316 +/- 192, n = 67) per the Vocabulary Production subscale. Composite scores on the SDQ and STSC did not differ between the higher-DHA group and the control group [SDQ Total Difficulties: higher-DHA group (10.3 +/- 6.0, n = 61), control group (9.5 +/- 5.5, n = 64), adjusted P = 0.5; STSC score: higher-DHA group (3.1 +/- 0.7, n = 61), control group (3.0 +/- 0.7, n = 64), adjusted P = 0.3]. CONCLUSIONS Feeding preterm infants milk containing 3 times the standard amount of DHA did not result in any clinically meaningful change to language development or behavior when assessed in early childhood. Whether longer-term effects of dietary DHA supplementation can be detected remains to be assessed. This trial was registered with the Australia and New Zealand Clinical Trial Registry at www.anzctr.org.au as 12606000327583.