Comparison of daily 400 and 600 units of vitamin D in prevention of osteopenia of prematurity in infants with gestational age of less than and equal to 32 weeks

Background: Use of vitamin D in premature infants is one of the important preventive factors for Osteopenia of prematurity but there are conflicting results on the appropriate doses, so this study aimed to compare the dose of 400 and 600 units vitamin D in the prevention of osteopenia of prematurity in infants with gestational age ≤ 32 weeks. Methods: This clinical trial study was conducted on 108 premature infants divided into two groups of 54 with gestational age of ≤ 32 weeks born between 2020-2021 in Shahid Beheshti and Al-Zahrai hospitals in Isfahan. In the first group, daily vitamin D was 400 units from the 7th day of birth, and in the second group, it was 600 units. At the age of 5 weeks, levels of calcium, phosphorus, alkaline phosphatase and vitamin D were evaluated. If the alkaline phosphatase level was above 1000, the wrist radiography was requested. Also, the baby was examined for clinical symptoms of rickets at the age of 5 weeks. The data were analyzed by SPSS software version 26 and P-value<0.05 was considered significant. Results: In the present study, there was no significant difference between the level of alkaline phosphatase in the two groups (p=0.596), but the level of vitamin D was significantly higher in 600 units group (p<0.001). The level of calcium was higher in 400 units group, but this difference was slightly significant (p=0.062). The level of phosphorus in 600 units group was higher than the 400 units, and the difference was slightly significant (P=0.062). Conclusion: The present study showed that daily 600 and 400 units of vitamin D in infants with gestational age of ≤ 32 weeks had no effect on the incidence of clinical symptoms and radiological findings of rickets at the age of 5 weeks.