Strømmen K, et al. Enhanced Nutrient Supply to Very Low Birth Weight Infants is Associated with Improved White Matter Maturation and Head Growth. Neonatology. 2015;107(1):68-75. This is a report of a secondary outcome of a small RCT, there were only 50 babies in total (the study was stopped early because of an increase in sepsis in the high nutrition group) and only 25 of them had the MR imaging; VLBW infants were randomized to standard nutrition, or an enhanced protocol which started IV amino acids at 3.5 g/kg/d increasing to 4.4.
Lipids were increased from 0.5 to 7 g/kg/day by day 10 in the control group and from 2.0 to 8.8 g/kg/day in the intervention group. The control group received the lipid emulsion ClinOleic ® (Baxter, Norway), whereas the intervention group received SMOFlipid ® (Fresenius Kabi, Norway) to ensure a higher supply of the essential fatty acids docosahexaenoic and arachidonic acid. The supply of proteins and lipids was gradually increased in both groups, mostly by increasing the enteral supply of human milk. Fortification was initiated when 110 ml/kg/day of human milk was tolerated with a gradual increase to 4.2 g Nutriprem /100 ml human milk. The intervention group received an additional enteral supply of amino acids (0.6 g Complete Amino Acid Mix)/100 ml human milk,
They also got additional docosahexaenoic acid and arachidonic acid.
Now I am all for enhanced nutrition, but that sounds really really enhanced, I don’t think I have ever given any where near that much lipid to a baby. The intervention group received a very high calorie intake, 166 kcal/kg/d, but even the controls got a lot of energy, 146 kcal. There was an even bigger difference in protein intake, 4.4 g/kg/d compared to 3.6 g. I have mentioned this study previously I think. it is a shame they stopped the study for a marginally significant finding on a secondary outcome, but I can certainly understand it, I don’t know if I would have had the guts, or the ruthlessly scientific approach, to continue a study when 61% of the intervention group have sepsis compared to 29% in the controls.
The point of this post though is that they did show that
1. Head circumference was closer to normal in the enhanced group
2. MRI Diffusion Tract Imaging (DTI) were much closer to normal in the enhanced nutrition group.
If the effect on sepsis is a real effect of the increased nutrition, then that outcome has to be balanced against the improved head growth and brain structure. Other studies, such as ours (which was not a randomized trial) did not show any increase in sepsis with increased nutrition, but we didn’t go near to their intakes. Is there a limit to calorie or fat or protein intakes that impairs white cell function? It certainly is possible, so we really need…. guess what? Randomized controlled trials, that’s what (suprise, surprise).