Multi-dose vitamin d supplementation in stable very preterm infants: Prospective randomized trial response to three different vitamin D supplementation doses

Background: Preterm newborns are born with lower vitamin D stores. Although vitamin D supplementation is recommended there is no consensus regarding the adequate dose of supplementation for preterm infants.

Aims: To assess the effect of three different doses of vitamin D supplementation (400, 800 and 1000IU/d) in preterm infants ≤32weeks gestation on the prevalence of vitamin D deficiency and 25(OH) D levels at 36weeks postmenstrual age (PMA).

Study design: Prospective randomized trial.

Subjects: 121 preterm infants with gestational age of 24-32weeks were randomly allocated to receive 400, 800 or 1000IU/d vitamin D.

Outcome measures: Serum concentration of 25(OH) D and the prevalence of vitamin D deficiency at 36weeks PMA. Vitamin D deficiency was defined as serum 25(OH) D concentrations <20ng/ml.

Results: Of the 121 infants 72% had deficient vitamin D levels before supplementation. The average 25(OH) vitamin D concentrations at 36weeks PMA were significantly higher in 800IU (40±21.4ng/ml) and 1000IU group (43±18.9ng/ml) when compared to 400IU group (29.4±13ng/ml). The prevalence of vitamin D deficiency (2.5 vs 22.5; RR: 0.09; CI:0.01-0.74) and insufficiency (30 vs 57.5; RR:0.32; CI:0.13-0.80) was significantly lower in 1000IU group when compared to 400IU group at 36weeks PMA.

Conclusion: 1000IU/d of vitamin D supplementation in preterm infants ≤32weeks gestation age effectively decreases the prevalence of vitamin D deficiency and leads to higher concentrations of 25(OH) vitamin D at 36weeks PMA TRIAL REGISTRATION: Clinical Trials.gov: NCT02941185.