The clinical efficacy of vitamin D in children with primary low bone mass

Abstract

Introduction: Vitamin D supplementation in prevention and treatment of osteoporosis is a widely accepted standard, but the latest studies show the necessity of increasing the intake of this vitamin to keep its concentration on higher levels - above 30 ng/ml. The best index describing the body vitamin D supply is hepatic metabolite of vitamin D (25OHD) concentration in the serum. There are few data on efficacy of this vitamin intake in children with low bone mass. AIM OF THE STUDY was to find out if vitamin D supplementation causes a significant increase in the hepatic metabolite concentrations and how it affects the clinical course of the disease and the results of densitometric tests in children with primary low bone mass.

Material and methods: Seventy six children aged 6 to 18.5 years (35 girls and 41 boys) with primary osteoporosis or low bone mass diagnosed based on clinical and densitometric signs were included in the study. In all children, the concentrations of 25OD and PTH were measured and densitometric evaluations were taken twice, before and after 1 year of vitamin D intake. According to literature data, 30 ng/ml was adopted as the lower limit of normal 25OHD levels in children with osteoporosis and low bone mass.

Results: Vitamin D supplementation for 12 months of osteoporosis and low bone mass therapy in children caused a statistically significant increase in concentrations of the hepatic metabolite of vitamin D and a significant reduction in serum PTH levels. The changes in 25OHD levels depended on the vitamin D dose used (658 IU/day), and only this amount allowed to achieve an improvement in the densitometric parameters, in particular the increase in bone mineral density (BMD) in the lumbar spine.

Conclusions: 1. Based on the performed study in children with idiopathic reduction of bone mineral density the normalisation of the calcitropic hormones and improvement in the densitometric parameters assessing bone mineral density is necessary. 2. A detailed statistical analysis has shown that the increase in both vitamin D metabolites and bone mineral density is caused by vitamin D supplementation at a dose of 685 IU/day; this is an important practical aspect of this study.