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

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.

[The vitamin D and calcium consumption and bone quality in children of lódZ (Poland) at the age 9-13 years]. / Spozycie witaminy D i wapnia a jakosc kosci dzieci lódzkich w wieku 9-13 lat.

INTRODUCTION: Only few publications concern the influence of the vitamin D and calcium consumption on the bone mineralization in the developmental age. AIM OF THE STUDY: The aim of the study was the analysis of the vitamin D and calcium diet supply in relation to the bone status assessed with Quantitative Ultrasound (QUS) in growing children. MATERIAL AND METHODS: The study comprised 643 pupils (384 girls and 259 boys) at the age 9-13 years from primary schools in lódZ. The medium daily consumption of vitamin D and calcium was estimated with the computer program Dieta 2. In all children the QUS was performed. RESULTS: Extreme deficiency of vitamin D was found in the diet of nearly all examined children (in 96,7% schoolgirls and 95,7% schoolboys). Girls consumed on average 25,5% of recommended values, boys 33,3%. Considerable deficiency of diet calcium was observed in 92% schoolgirls and 81,9% of schoolboys. The medium daily consumption of calcium was higher than vitamin D and reached 59,2% of recommended values in girls and 66,2% in boys. In 48% of children an decrease of at least one of the QUS parameters was observed. The statistical analysis showed positive, significant correlation between QUS parameters and calcium consumption, it was not observed for vitamin D. CONCLUSIONS: 1. The deficiency of diet vitamin D and calcium is common in children in lódZ. 2. The extremely low supply of diet vitamin D does not meet the recommended values. 3. The lowering of the QUS parameters observed in 48% of children indicates for worse bone mineralization and bone quality. 4. The results of this study indicate for the necessity of changes in nutritional habits of children and adolescence and if it is not possible the supplementation of vitamin D and calcium.