Efficacy of Prevention and Correction of Vitamin D Deficiency using Therapeutic Doses of Cholecalciferol in Children under Three Years of Age

Methods: 93 children aged from 1 month to 3 years living in Stavropol (45° North). 42 (45.2%) children were under 12 m, 25 (26.9%) - from 12 to 24 m, and 26 (27.9%) - from 24 to 36 m. Following determination of the baseline serum concentration of 25(OH)D, the study participants were prescribed ChoC for 30 days: 3,000 IU/day for subjects having 10-19 ng/mL serum 25(OH)D; 2,000 IU/day and 1,000 IU/mL for those having 20-29 ng/mL and >30 ng/mL serum concentrations of 25(OH)D. Control laboratory tests were performed after a 30-day treatment course with vitamin D (VD).

Results: Median baseline level (Me [25Q-75Q]) of calcidiol in the group examined was 25.4 [20.0-31.2] ng/mL. After 1 month use of ChoC according to the suggested dosage regimen, serum 25(OH)D demonstrated two-fold increase up to 49.1 [40.5-64.5] ng/mL compared to baseline (p<0.001). The calcidiol level in subjects receiving VD at the dose of 1,000 IU/day increased from 39.5 [33.4-48.5] to 45.5 [39.6-57.9] ng/mL (p<0.05); from 24.9 [22.6-26.5] to 49.2 [41.0-66.6] ng/mL (p<0.001) and from 14.1 [12.0-16.1] to 53.1 [42.7-68.1] ng/mL (p<0.001) in subjects receiving 2,000 IU/day and 3,000 IU/day doses. The levels of 25(OH)D within the range of 20-30 ng/mL were registered in 40 (43.0%) and 8 (8.6%) subjects (p<0.001); and the levels within the range of 30-100 ng/mL were observed in 30 (32.3%) and 80 (80.6%) children, respectively (p<0.001). Calcidiol concentration above 100 ng/mL was revealed in 4 (4.3%) children. The correlation between the daily dose of ChoC and the increment of 25(OH)D as a result of one-month treatment course comprised r=0.57 (p<0.001).

Conclusion: The highest increments of calcidiol were observed when the ChoC doses of 2,000-3,000 IU/day were used