ABSTRACT
BACKGROUND: In 2017, the neonatal intensive care unit (NICU) at Rush University Medical Center (RUMC) implemented a protocol to provide individualized vitamin D supplementation dosing for very low-birth-weight (VLBW) and very preterm infants. This study evaluated the association of demographic and socioeconomic factors, vitamin D dose, and health indicators, including bone mineral status, measured by alkaline phosphatase and phosphorus levels; linear growth velocity; and occurrence of fractures. METHOD: This retrospective cross-sectional study included 227 VLBW or very preterm infants (34 VLBW, 12 very preterm, and 181 VLBW and very preterm) born in and discharged from the RUMC NICU between February 1, 2017, and October 31, 2019. Vitamin D dose was classified as adjusted (supplemental dose of 800 IU/day, n = 169) or standard (recommended dose of 400 IU/day, n = 58), per the protocol. Binary logistic and linear regression models were constructed to test the associations between infant and maternal characteristics and vitamin D dose group and between vitamin D dose group and health indicators. RESULTS: The analysis found a statistically significant association between maternal age, gestational age, infant birth weight, and race/ethnicity and receipt of an adjusted vitamin D dose. No significant associations were found between health indicators and vitamin D dose. CONCLUSION: Sociodemographic factors may influence vitamin D deficiency in VLBW and very preterm infants in the NICU. At this time, there is insufficient evidence to support a tailored approach, but further research in this area is warranted.
