Association of pediatric trace element formulations with cholestasis and growth outcomes in very low birth weight infants: a propensity-matched cohort study

Various formulations of trace element injections are available for clinical use. In some healthcare settings, adult formulations continue to be used in infants and young children instead of switching to dedicated pediatric preparations. Although pediatric formulations are designed for age-appropriate dosing, whether they offer measurable clinical advantages over adult formulations in very low birth weight (VLBW, birth weight < 1500 g) infants remains unclear. This retrospective study aimed to evaluate the impact of two different trace element formulations used during parenteral nutrition on complication rates and growth outcomes in VLBW infants. Specifically, we compared a pediatric-formulation trace element injection (commercial name: Trace Element Injection I; denoted as “pediatric formulation”) versus an adult-formulation injection (commercial name: Trace Element Injection II; denoted as “adult formulation”). We retrospectively analyzed VLBW infants who received different trace element injections at Bao’an District Maternal and Child Health Hospital in Shenzhen between 2016 and 2022. As the hospital switched from the adult to the pediatric formulation in 2021, this study essentially compares two treatment eras. Propensity score matching was used to balance baseline covariates, and outcomes were compared between the two groups. A total of 374 VLBW infants receiving parenteral trace element injections were included (187 per group). After propensity score matching, 208 infants (104 per group) were compared. The pediatric formulation group showed a significantly lower incidence of cholestasis than the adult formulation group (6.7% vs. 16.3%, p = 0.03), Logistic regression analysis further confirmed that the choice of Multi-Trace Element Injection was an independent factor influencing the development of cholestasis(Optimized Model: OR = 0.165(0.042–0.654), NNT = 8(7–20), ARR = 13.2%(5.0%-15.5%), p = 0.010). For growth outcomes, unadjusted analysis revealed greater weight gain at 30 days in the pediatric formulation group [495.32 ± 159.06 g vs. 441.54 ± 177.72 g, p = 0.025]; however, this difference did not persist after multivariable adjustment (β = 29.883(-17.321 to 77.087), p = 0.213). This study demonstrates that the use of pediatric trace element formulations, compared with adult formulations, in the PN of VLBW infants is associated with a lower incidence of cholestasis. The observed advantage in 30-day weight gain was attenuated after adjusting for confounders and warrants further investigation. Overall, our findings support the preferential use of pediatric trace element formulations in this vulnerable population. Not applicable.