IMPE Abstracts

Objectives: Vitamin D deficiency is prevalent in pediatric population. Since low compliance may inhibit appropriate vitamin D supplementation in daily dosing regimen, intermittent high dose administration may be considered. We aimed to evaluate the efficacy and safety of monthly administration of oral cholecalciferol compared with daily dosing regimen in adolescents with vitamin D deficiency.

Methods: This retrospective study included 175 vitamin D deficient (serum 25-hydroxyvitamin D [25OHD] < 20 ng/mL) children with precocious puberty (64 boys, 10.5 ± 1.5 years) who received gonadotropin-releasing hormone agonist every 4 weeks between December 2019 and September 2021. Among them, 93 children received 1,000 IU of oral cholecalciferol every day [daily group] and 82 children received 25,000 IU of oral cholecalciferol every 4 weeks [monthly group]. Serum calcium and 25OHD levels were measured before and after treatment.

Results: Baseline 25OHD levels did not differ between two groups (13.9 ± 3.1 in daily group vs. 13.6 ± 3.5 ng/mL in monthly group, P=0.511). After median follow-up of 5.8months (interquartile range 4.7 – 6.8 months), increase in serum 25OHD concentrations were higher in monthly group than in daily group (9.7 ± 5.1 vs. 8.4 ± 7.1 ng/mL, P=0.027). The corrected dose-response was also higher in monthly group than in daily group (10.9 ± 5.7 vs. 8.4 ± 7.1 ng/mL increase per 1,000IU/daily, respectively, P=0.001). The proportion of patients attaining non-deficient vitamin D status (25OHD > 20 ng/mL) after treatment was 76.8% and 58.1% in monthly and daily groups, respectively (P=0.013). Hypercalcemia was not observed in both groups.

Conclusions: Monthly administration of oral cholecalciferol 25,000IU every 4 weeks showed higher efficacy andequivalent safety profiles compared with conventional daily administration in adolescents with vitamin D deficiency. It needs to be further investigated whether monthly administration of cholecalciferol have more benefits in pediatric population.

Keywords: Vitamin D Deficiency, Children, Adolescent, Treatment Outcome, Safety