The interplay between early energy intake and nosocomial infection risk in the critically ill neonate

This study aimed to assess the association between early nutritional support - specifically the attainment of predefined energy targets - and the risk of hospital-acquired infections (HAIs) in critically ill neonates. We conducted a retrospective cohort study involving 200 critically ill neonates admitted to a tertiary neonatal intensive care unit between January 2022 and December 2023. Participants were stratified into 2 exposure groups according to the timing of nutritional initiation and adequacy of energy/protein intake during the first postnatal week: an early-adequate nutrition group (n = 92) and a delayed or insufficient nutrition group (n = 108). A multivariable logistic regression model was fitted to evaluate the independent effect of energy target achievement on HAI risk, with additional subgroup and sensitivity analyses to assess robustness. The cohorts were largely comparable at baseline, although birth weight was significantly higher in the early-adequate nutrition group (1605 ± 390 vs 1470 ± 440 g, P = .02). Initiation of nutritional support occurred earlier in the early-adequate group, resulting in significantly greater cumulative energy and protein intake by day 7. The energy target achievement rate was 100% in the early-adequate group, compared with 33.3% in the delayed/insufficient group (P < .001). Throughout the follow-up period, 48 neonates (24.0%) developed HAIs, with a significantly lower incidence observed in the early-adequate nutrition group (15.2% vs 31.5%, P = .008). Quartile-based analysis demonstrated a clear inverse dose-response relationship between energy intake and infection incidence (P for trend = .001). After adjusting for potential confounders, achievement of the energy target (≥60 kcal/kg/d) remained independently associated with reduced HAI risk (adjusted odds ratio = 0.45, 95% confidence interval = 0.22-0.89, P = .02). Subgroup analyses revealed a more pronounced protective effect among very low birth weight infants and those born at <28 weeks' gestation. Sensitivity analyses confirmed the consistency of these findings across alternative energy thresholds (60, 70, and 80 kcal/kg/d). Early attainment of energy targets is independently associated with a reduced incidence of HAIs in critically ill neonates, underscoring the vital role of timely and sufficient nutritional support in mitigating infectious complications in the neonatal intensive care unit setting.