Since a trial which randomizes premature infants into groups that are well-nourished and poorly-nourished and then following them prospectively is never going to happen, it is difficult to know with certainty the effects of optimal nutrition are with respect to long-term neurodevelopmental outcomes.
An article I enjoyed reading on this subject (MB Belfort et al. J Pediatr 2016; 168: 30-5) pushes back on the correlation between good weight gain, as a surrogate marker for nutritional status, and neurodevelopmental outcomes.
In this study, 1070 infants between 23-27 weeks gestational age were followed with weights on days 7-28 along with weights at 12 and 24 months. This data was compared with several indices on neurodevelopmental outcome. Here is the key finding: “Weight gain in the lowest quartile from 7-28 days was not associated with higher risk of adverse outcomes.”
In commentary on their findings, the authors point out that “we found no evidence to suggest that faster weight gain from 7 to 28 days of life reduced the risk of adverse outcomes…almost all of the associations between low weight gain..were attenuated or eliminated when we restricted our analysis to those children able to walk independently.”
“Overall, it appears that low weight in children with severe neurodevelopmental impairments may be caused by factors closely related to the impairments themselves…reverse causation may be at play.” Thus, underlying brain damage may limit body weight gain, rather than poor nutrition limiting brain development.”
My take: I may be apt to ‘confirmational bias’ as this study reinforces my view that improved nutrition may not change outcomes appreciably. To be clear, I still believe that efforts to optimize the nutrition of premature infants are a good idea but we need to be skeptical about the magnitude of benefit that we will derive.
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