For this study, researchers wanted to see how two different vitamin D dosages affected the expression of T regulatory cells (Treg) in preterm newborns. A double-blind randomized controlled experiment was undertaken on preterm children born between 280/7 and 336/7 weeks gestation. When subjects attained 100 mL/kg of enteral feeds, they were randomly allocated to receive 400 or 800 IU/day of vitamin D3. Flow cytometry was used to determine the percentage increase in Treg cell counts at enrolment, as well as after 1 and 4 weeks of oral vitamin D treatment at the prescribed levels in both groups. The effects of short-term morbidity and death were also evaluated. A total of 40 newborns were recruited, with 20 in each group.
After 1 week (1.9 ± 5.5 vs 60 ± 5.6, P = 0.0005) and 4 weeks (1.8 ± 5.7 vs 73.7 ± 5.6, P = 0.0028), the change in Treg count (%) was considerably lower in the low-dose vitamin D3 supplementation group. Anthropometric measures, duration of oxygen and respiratory assistance, and death did not differ between the two groups. The low-dose group had a longer hospital stay (24.9 ± 5.14 vs 22 ± 3.49, P = 0.04). Oral vitamin D treatment has dosage and time-dependent influence on the proportion of Treg in preterm newborns. The 800 IU vitamin D3 dosage had no evident short-term adverse effects. Larger studies are needed to investigate the effect of vitamin D3 supplementation on hospital stay duration.
Reference:journals.lww.com/jpgn/Fulltext/2019/11000/Vitamin_D_Supplementation_and_T_Cell_Regulation_in.19.aspx
