Alternative lipid emulsions versus pure soy oil based lipid emulsions for parenterally fed preterm infants.

Systematic review and meta-analysis of randomized trials in preterm infants receiving parenteral nutrition in NICUs. The review included 15 studies and pooled active intervention arms across alternative lipid emulsions versus soybean oil-based lipid emulsions, with infants generally born very preterm or very low birth weight across multiple countries.

The intervention was parenteral lipid emulsions for preterm infants, comparing newer alternative formulations with pure soybean oil-based lipid emulsions. Alternative regimens included mixed lipid emulsions containing medium-chain triglycerides, olive oil, soybean oil, and fish oil; olive-oil based emulsions; medium-chain/soybean emulsions; fish-oil containing emulsions; and structured lipid preparations, generally given by continuous intravenous infusion over days to weeks as part of parenteral nutrition. Comparator arms received conventional soybean oil-based lipid emulsions such as Intralipid or similar formulations.

Overall, there was no convincing evidence that any alternative lipid emulsion was superior to pure soybean oil-based lipid emulsions in preterm infants. Across pooled comparisons, there were no statistically significant differences in death before discharge, growth, bronchopulmonary dysplasia/chronic lung disease, sepsis, severe retinopathy of prematurity, or parenteral nutrition-associated liver disease. Examples include MOFS-LE versus soybean oil-based lipid emulsion for death before discharge RR 1.26, 95% CI 0.68 to 2.31; BPD/CLD RR 1.02, 95% CI 0.70 to 1.49; and any sepsis RR 0.94, 95% CI 0.62 to 1.42. OS-LE versus soybean oil-based lipid emulsion also showed no clear benefit for death before discharge RR 1.00, 95% CI 0.21 to 4.82 or BPD/CLD RR 0.69, 95% CI 0.46 to 1.04. The authors concluded that larger, well-powered trials are needed to determine whether any clinically important benefit exists.

The evidence base was generally low to very low quality, with small, often single-center trials and substantial heterogeneity across lipid formulations, doses, durations, and outcome definitions. Several comparisons included only one or a few studies, leaving many estimates imprecise with wide confidence intervals. This limits confidence in detecting small benefits or harms and reduces generalizability.