Vitamin D status as related to race and feeding type in preterm infants

Abstract

Background: Despite the higher prevalence of vitamin D deficiency in blacks, the vitamin D status of black preterm infants remains unknown. In addition, with the combination of parenteral and enteral nutritional support that preterm infants receive, the effect of vitamin D-deficient breast milk on vitamin D status is unknown.

Objective: To evaluate vitamin D status of preterm infants through the first month after delivery and compare status by race and feeding type.

Study design: Thirty-six (36) preterm (< or =32 weeks gestation) infants (19 black, 17 white) had assessment of feeding type, vitamin D intake, and serum 25-hydroxyvitamin D [25(OH)D] as a marker of vitamin D status at three time points in the first month after delivery.

Results: Black infants had a significantly lower mean 25(OH)D level on day 7-8 and day 14-15 evaluations than white infants [14.9 +/- 6.6 versus 23.3 +/- 9.3 ng/mL (p = 0.021) and 18.3 +/- 7.3 versus 25.6 +/- 10.3 ng/mL (p = 0.048), respectively], but the difference was no longer significant by day 28-30 evaluation [19.6 +/- 7.7 versus 26.2 +/- 11.6 ng/mL (p = 0.26)]. Vitamin D status was not significantly lower in infants receiving predominantly breast milk (p = 0.6). Vitamin D intake rose through the month as the amount and caloric density of enteral nutrition increased. Six infants had significant decrease in serum 25(OH)D values from day 14-15 to day 28-30 evaluation despite receiving > 400 IU/day vitamin D.

Conclusion: Differences in vitamin D status occurred between black and white infants and were significant through the first 2 weeks after delivery. Infants receiving predominantly breast milk did not have significantly worse vitamin D status than those receiving formula. The significant decline in serum 25(OH)D status observed in 28% of the infants was not related to breast milk intake.