Three monthly doses of 150,000 IU of oral cholecalciferol correct vitamin D deficiency in adolescents: A pragmatic study

Objectives To assess the efficacy of an oral high‐dose cholecalciferol regimen in correcting vitamin D deficiency (VDD) in adolescents and to explore potential predictive factors on the response to treatment. Methods This is a retrospective chart review conducted in the Adolescent Outpatient Clinic, Geneva University Hospitals, Switzerland. One hundred‐three otherwise healthy vitamin D deficient [serum 25‐hydroxyvitamin D, 25(OH)D, level <50 nmol/L] adolescents (mean age 16.6) attending the clinic between 1 January 2016 and 31 December 2018 received 150,000 IU of oral cholecalciferol every month for 3 months (cumulative dose of 450,000 IU). We measured the change in serum 25(OH)D levels pre‐ and post‐treatment and the achievement of serum 25(OH)D level post‐treatment ≥75 nmol/L. Results The mean serum 25(OH)D level increased by 320%, from 26 nmol/L at baseline to 83 nmol/L at the end of the study ( P  < .001). The rise was significantly higher for patients initially tested in the winter/spring (mean 65 nmol/L) compared with those initially tested in the summer/autumn (mean 48 nmol/L) ( P  < .003). No clear relationship was found between the response to treatment and the vitamin D status at baseline. The effect of age, gender, origin and body mass index was not statistically significant. Conclusions The present intermittent high‐dose regimen is effective in treating VDD in healthy adolescents without significant variations in response between different subgroups.