Survey of vitamin D supplementation practices in extremely preterm infants.

BACKGROUND: Most extremely preterm (EP) infants are vitamin D deficient (serum 25-hydroxyvitamin D levels below 20 ng/mL), and optimal supplementation practices for EP infants remain unknown. Our objective is to assess current vitamin D supplementation practices in U.S. neonatal intensive care units (NICU) for EP infants to provide baseline information for the design of future clinical trials. METHODS: We conducted an online survey to study vitamin D intake and supplementation practices in U.S. NICUs caring for EP infants. Descriptive statistics compared responses by affiliation and level of care. RESULTS: We analyzed responses from 253 NICUs, representing the majority of academic and level IV centers. Nearly all centers (97%) provided enteral vitamin D supplementation during the NICU stay, with 400 IU/day as the most common dosage (77%). Over half (56%) used feeding volume to initiate supplementation, with 71% of centers starting after achieving at least 120 ml/kg/day. Additionally, 94% of NICUs reported prescribing a vitamin D supplementation at discharge. CONCLUSIONS: Most NICUs in the U.S. supplement EP infants with 400 IU/day of enteral vitamin D. Clinical trials of vitamin D supplementation comparing the most common regimen to earlier and higher doses are needed to identify adequate regimens for EP infants. IMPACT: Despite the prevalence of vitamin D deficiency in extremely preterm (EP) infants at birth, optimal levels and supplementation strategies remain debated. Recent studies have suggested benefits of early high-dose vitamin D supplementation (800 IU/day) for reducing complications like bronchopulmonary dysplasia, infections, and disability. There is US center variation in timing and dose of vitamin D supplementation, being the most common regimen 400 IU/d started after established feedings (≥120 ml/kg/day). These findings inform and highlight the need for clinical trials of usual vs. early, higher-dose vitamin D supplementation to advance clinical outcomes and define desirable blood levels of EP infants.

Randomized Controlled Trial of Enteral Vitamin D Supplementation (ViDES) in Infants <28 Weeks Gestational Age or <1000 Grams Birth Weight: Study Protocol.

Background: Vitamin D is necessary to develop healthy lungs and other organs early in life. Most infants born before 28 weeks' gestation have low vitamin D levels at birth and a limited intake during the first month. Enteral vitamin D supplementation is inexpensive and widely used. The appropriate supplementation regimen for extremely preterm infants is controversial, and the effect of different regimens on their blood levels and outcomes is unclear. Methods: Randomized, blinded comparative effectiveness trial to compare two vitamin D supplementation regimens for inborn infants <28 weeks gestation or <1000 grams birth weight at a large academic center in the United States.Infants are stratified by birth weight and randomized within 96 hours after birth to either routine supplementation (400 IU/day with established feedings) or increased supplementation (800 IU/day with any feedings) during the first 28 days after birth.We hypothesize that the higher and early vitamin D dose (800 IU/d with early feeding) compared to placebo plus routine dose (400 IU/d with established feeding) will substantially increase total 25-hydroxyvitamin D3 levels measured as state-of-art at one month, reduce respiratory support at 36 weeks' postmenstrual age (on an ordinal scale predictive of later adverse outcomes) and improve or at least not worsen other important secondary outcomes. The infants in the study will follow up at 22-26 months' corrected age (~2 years) with blinded certified examiners to evaluate neurodevelopmental outcomes.The sample size of a minimum of 180 infants provides >90% power to detect a >95% posterior probability of a 33% increase in serum 25-hydroxy vitamin D3 and >80% power to detect a >80% posterior probability of a relative risk decrease of 20% of reducing respiratory support by intention-to-treat Bayesian analyses using a neutral prior probability. Discussion: Our study will help clarify the uncertain relationship of vitamin D supplementation and its associated serum metabolites to clinical outcomes of extremely preterminfants. Confirmation of our hypotheses would prompt reconsideration of the supplementation regimens used in extremely preterm infants and justify a large multicenter study to verify the generalizability of the results. Trial registration: ClinicalTrials.gov registered on July 14, 2022 (NCT05459298).

Randomized controlled trial of enteral vitamin D supplementation (ViDES) in infants <28 weeks gestational age or <1000 g birth weight: study protocol.

BACKGROUND: Vitamin D is necessary to develop healthy lungs and other organs early in life. Most infants born before 28 weeks' gestation have low vitamin D levels at birth and a limited intake during the first month. Enteral vitamin D supplementation is inexpensive and widely used. The appropriate supplementation regimen for extremely preterm infants is controversial, and the effect of different regimens on their blood levels and outcomes is unclear. METHODS: Randomized, blinded comparative effectiveness trial to compare two vitamin D supplementation regimens for inborn infants <28 weeks gestation or <1000 g birth weight at a large academic center in the United States. Infants are stratified by birth weight and randomized within 96 h after birth to either routine supplementation (400 IU/day with established feedings) or increased supplementation (800 IU/day with any feedings) during the first 28 days after birth. We hypothesize that the higher and early vitamin D dose (800 IU/day with early feeding) compared to placebo plus routine dose (400 IU/day with established feeding) will substantially increase total 25-hydroxyvitamin D3 levels measured as state-of-art at 1 month, reduce respiratory support at 36 weeks' postmenstrual age (on an ordinal scale predictive of later adverse outcomes), and improve or at least not worsen other important secondary outcomes. The infants in the study will follow up at 22-26 months' corrected age (~2 years) with blinded certified examiners to evaluate neurodevelopmental outcomes. The sample size of a minimum of 180 infants provides >90% power to detect a >95% posterior probability of a 33% increase in serum 25-hydroxy vitamin D3 and >80% power to detect a >80% posterior probability of a relative risk decrease of 20% of reducing respiratory support by intention-to-treat Bayesian analyses using a neutral prior probability. DISCUSSION: Our study will help clarify the uncertain relationship of vitamin D supplementation and its associated serum metabolites to clinical outcomes of extremely preterm infants. Confirmation of our hypotheses would prompt reconsideration of the supplementation regimens used in extremely preterm infants and justify a large multicenter study to verify the generalizability of the results. TRIAL REGISTRATION: ClinicalTrials.gov NCT05459298. Registered on July 14, 2022.

Practical approaches for supporting informed consent in neonatal clinical trials.

The survival and health of preterm and critically ill infants have markedly improved over the past 50 years, supported by well-conducted neonatal research. However, newborn research is difficult to undertake for many reasons, and obtaining informed consent for research in this population presents several unique ethical and logistical challenges. In this article, we explore methods to facilitate the consent process, including the role of checklists to support meaningful informed consent for neonatal clinical trials. CONCLUSION: The authors provide practical guidance on the design and implementation of an effective consent checklist tailored for use in neonatal clinical research.

Fetal lung hypoxia and energetic cell failure in the nitrofen-induced congenital diaphragmatic hernia rat model.

PURPOSE: Congenital diaphragmatic hernia (CDH) pathogenesis is poorly understood. We hypothesize that fetal CDH lungs are chronically hypoxic because of lung hypoplasia and tissue compression, affecting the cell bioenergetics as a possible explanation for abnormal lung development. METHODS: To investigate this theory, we conducted a study using the rat nitrofen model of CDH. We evaluated the bioenergetics status using H1 Nuclear magnetic resonance and studied the expression of enzymes involved in energy production, the hypoxia-inducible factor 1α, and the glucose transporter 1. RESULTS: The nitrofen-exposed lungs have increased levels of hypoxia-inducible factor 1α and the main fetal glucose transporter, more evident in the CDH lungs. We also found imbalanced AMP:ATP and ADP:ATP ratios, and a depleted energy cellular charge. Subsequent transcription levels and protein expression of the enzymes involved in bioenergetics confirm the attempt to prevent the energy collapse with the increase in lactate dehydrogenase C, pyruvate dehydrogenase kinase 1 and 2, adenosine monophosphate deaminase, AMP-activated protein kinase, calcium/calmodulin-dependent protein kinase 2, and liver kinase B1, while decreasing ATP synthase. CONCLUSION: Our study suggests that changes in energy production could play a role in CDH pathogenesis. If confirmed in other animal models and humans, this could lead to the development of novel therapies targeting the mitochondria to improve outcomes.