624 - Feeding Outcomes in Infants Under 30 Weeks Gestational Age in a Level IV Neonatal Intensive Care Unit. A Retrospective Cohort Study

Publication Number: 1601.624

Ana Nevarez Gilbert, University of Iowa, Iowa City, IA, United States; Samuel Wong, University of Iowa, Iowa City, IA, United States; Adrianne R. Bischoff, University of Iowa Stead Family Children's Hospital, Iowa City, IA, United States; Tarah Colaizy, University of Iowa Stead Family Children's Hospital, Iowa City, IA, United States; Aamer Imdad, university of, Iowa City, IA, United States

Background: Prematurity affects 10% of U.S. births, with increasing rates in recent years. Extremely preterm infants often experience prolonged hospitalization due to immature organ systems and feeding challenges. Oral feeding competency is a key discharge criterion, yet up to 37% of premature infants remain admitted at 36 weeks PMA due to inadequate oral intake, which is associated with poor growth, neurodevelopmental outcomes, and increased healthcare costs

Objective: To identify the association of timing of initiation of oral feeds with achievement of full oral feeds at 36-38 weeks PMA, at discharge and length of hospital stay

Design/Methods: Retrospective cohort analysis of infants born at ≤30 weeks gestation at the University of Iowa NICU from January 1, 2019, to June 30, 2024. Descriptive statistics will report demographics and feeding milestones. Dichotomous outcomes will be described with proportions. Continuous outcomes will use means with SD if normally distributed, otherwise medians with IQR. Univariable analysis will assess selected demographics and outcomes, followed by multivariable regression models for other associations. Study approved by the University of Iowa IRB

Results: A total of 404 infants were included. Median gestational age was 27 weeks [I25-28], and birth weight 925 g [675-1162]. Enteral feeds began on day 1 [1-2], oral feeds began on day 63 [46-97], corresponding to 36 weeks PMA [34-39]. Time to full enteral feeds was 24 days [17-35], and to full oral feeds was 20 days [13-28]. Median PMA at discharge was 41 weeks [38-45], with hospital stay of 98 days [76-134]. Later initiation of oral feeds was strongly associated with reduced odds of oral independence at 36 weeks (OR 0.32, 95% CI: 0.22-0.47), 38 weeks (OR 0.30, 95% CI: 0.23-0.40), and discharge (OR 0.72, 95% CI: 0.65-0.80), all p< 0.001. Adjusting for clinical covariates, each 1-week delay decreased the odds by 68%, 70%, and 28% respectively, while earlier initiation tripled odds at 36 and 38 weeks and increased odds by ~39% at discharge. BPD significantly reduced odds at earlier timepoints. Gestational age, birth weight, and sex were not significant predictors. Additionally, each 1-week delay prolonged hospitalization by ~9.95 days (β=9.95, 95% CI: 9.30-10.60, p< 0.001)

Conclusion(s): Later initiation of oral feeds was strongly associated with reduced odds of achieving oral feeding independence at 36 weeks PMA, 38 weeks PMA, and discharge. Regression models adjusting for clinical covariates showed that each one-week delay in oral feed initiation significantly decreased feeding success across all timepoints and prolonged hospital stay

Study Demographics
Table 1: Study demographics. *OFC = Occipitofrontal circumference. Continuous variables are presented as median [IQR] unless otherwise specified (mean ± SD for discharge length and OFC). Categorical variables are presented as n (%)

Association of PMA at Introduction of Oral Feeds and Oral Independence at Three Timepoints
Table 2: Multivariable regression model to evaluate association of PMA at introduction of oral feeds and oral independence at three timepoints, adjusting for gestational age, birthweight, sex, BPD and hsPDA. Abbreviations: PMA = postmenstrual age; PO = oral feeds; BPD = bronchopulmonary dysplasia; hsPDA = hemodynamically significant patent ductus arteriosus. Confidence intervals (CI) are reported at 95% level

Adjusted Analysis of PMA at initiation of oral feeds and PMA at full oral feeds