If the standard supplementation of 400 IUs of vitamin D is increased to 800 IUs daily there are reductions in the number of premature and preterm babies with extremely low bone density, found a University of Nebraska Medical Centre study.
Physicians have been prescribing vitamin D in premature and preterm infants in neonatal intensive care units (NICU) to prevent rickets, a disease that causes soft, weak bones in children and is often associated with vitamin D deficiency. In spite of this, a sizeable number of infants still develop rickets, said Dr Ann Anderson Berry, associate professor in the division of newborn medicine and medical director of the NICU at Nebraska Medicine, UNMC’s clinical partner.
She said current recommendations of vitamin D supplementation for preterm infants span a wide range of doses, even among major medical groups such as the American Academy of Paediatrics, the Institute of Medicine, and the Endocrine Society. And response to vitamin D supplementation and impact on outcomes in preterm infants is not well understood, she said.
The study provided more evidence in regards to bone health and ideal supplementation. The objective was to evaluate changes in vitamin D in the blood over four weeks in two groups of premature infants born between 24 to 32 weeks gestation. Researchers studied 32 infants at doses of 400 or 800 IU/day of vitamin D.
Researchers saw an improvement in bone density and vitamin D levels in the blood at four weeks. They also saw improvement in growth that significantly decreased the risk of infants having very low bone density.
“We are hopeful that neonatologists will consider giving pre-term infants 800 IUs,” Anderson Berry said. “We know that even with standard vitamin D dosing, we were still seeing a fair number of pre-term infants who suffered from impaired bone health. This is another form of NICU therapy that can help decrease that risk.”
She said the study is one of the first to look at higher dosing of vitamin D in premature infants. Information will be incorporated as a recommended practice for health professionals.
Background: Recommendations for vitamin D supplementation for preterm infants span a wide range of doses. Response to vitamin D supplementation and impact on outcomes in preterm infants is not well understood.
Objective: Evaluate serum 25(OH)D3 concentration changes after 4 weeks in response to two different doses of vitamin D3 supplementation in a population of premature infants and quantify the impact on NICU outcomes.
Design: 32 infants born at 24–32 weeks gestation were prospectively randomized to receive 400 or 800 IU/day vitamin D3 supplementation. Serum 25(OH)D3 levels were measured every 4 weeks. The Wilcoxon signed rank test was used to compare serum levels of 25(OH)D3 at 4 weeks and each subsequent time point. A p-value of <0.05 was considered statistically significant.
Results: Serum 25(OH)D3 levels at birth were 41.9 and 42.9 nmol/l for infants in the 400 IU group and 800 IU group, respectively (p = 0.86). Cord 25(OH)D3 concentrations significantly correlated with gestational age (r = 0.40, p = 0.04). After 4 weeks of D3 supplementation, median 25(OH)D3 levels increased in both groups (84.6vs. 105.3 nmol/l for 400 vs. 800 IU/day respectively, with significantly more improvement in the higher dose (p = 0.048). Infants in the 400 IU group were significantly more likely to have dual energy x-ray absorptiometry (DEXA) bone density measurements <10 percentile (56% vs 16%, p = 0.04).
Conclusions: Improvement in 25(OH)D3 levels at 4 weeks, bone density, and trends towards improvement in linear growth support consideration of a daily dose of 800 IU of vitamin D for infants <32 weeks cared for in the NICU.
Ann Anderson-Berry, Melissa Thoene, Julie Wagner, Elizabeth Lyden, Glenville Jones, Martin Kaufmann, Matthew Van Ormer, Corrine Hanson
University of Nebraska Medical Centre material[/link]
PLOS One abstract