Low levels of the long-chain polyunsaturated fatty acids (LCPUFA) docosahexanenoic acid (DHA) and arachidonic acid (ARA) in premature infants are correlated with an increased risk of developmental, respiratory, and infectious morbidities in premature infants. A new report suggests that prolonged exposure to intravenous lipids exacerbates these low levels and could contribute to poor neurodevelopmental outcomes (J Pediatr 2013; 162: 56-61).
This study followed 26 extremely low birth weight premature infants with serial blood draws during the first two months of life using a prospective cohort design. Infants who received more than 28 days of intravenous lipid emulsion had significantly decreased DHA levels compared to infants with shorter duration of parenteral lipid exposure; at 8 weeks, the DHA levels were 2.7 ± 0.6 compared with 4.2 ± 1.9 (all levels reported as g/100 g). DHA levels at birth were 5.5 ± 1.4.
ARA levels decreased in a similar fashion in both groups, though values were mildly lower in the prolonged lipid group. At 8 weeks, the ARA values were 9.4 ± 1.6 and 11.5 ± 2.5 respectively. Thus, with a larger study group, this could be a significant finding as well.
These lower LCPUFA (especially DHA) levels may reflect a suboptimal intravenous lipid emulsion. Alternatively, the underlying reason for the prolonged lipids, like sepsis and NEC , could result in these lower levels. Perhaps attention to LCPUFA in parenteral formulations can improve neurodevelopmental outcomes in this vulnerable population.
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