Katarína Janíková1, Lenka Vojarová1, Zuzana Michnová1, Martin Janík2, Peter Bánovčin1
Aims: To establish the prevalence of reduced vitamin D levels in the group of healthy children aged 4-8 years. To compare the differences between the sexes in the particular sample. To evaluate the correlation between the vitamin D insufficiency and bone mineral density within the examined sample. Methods: The study includes 35 children, white, aged 4-8 years. 21 girls and 14 boys. Within the study, following parameters were determined: serum vitamin D concentration (25-hydroxyvitamin D) – as a marker of whole-body vitamin D status, serum levels of parathyroid hormone, calcium and ionised calcium. The bone mineral density in the lumbar and whole-body area was measured by the densitometer Hologic Discovery®. The data were statistically processed using the Mann-Whitney test. Results: At the values of vitamin D insufficiency being determined by serum levels < 20 ng/ml, we detected the prevalence of vitamin D insufficiency in 34.29 % of the total number of children. In the girls’group, a higher occurence of vitamin D insufficiency was observed compared with the boys´group (42.86 % versus 21.43%). We detected considerably higher levels of vitamin D in boys than in girls (p = 0.0082). No statistically significant correlation was established between the group of children with vitamin-D insufficiency and the children with its higher physiological levels in the values of bone mineral mass either in the lumbar area (p = 0.498) or the values of bone mineral mass in the whole-body area (p = 0.808). Also, no significant difference in the parameters of serum levels of parathyroid hormone (p = 0.566), calcium (p = 0.498) and ionised calcium (p = 0.602) in children with reduced vitamin D levels and in children with its physiological levels was detected. Conclusions: The study confirmed the reduced vitamin D levels in the sample of healthy children’s subjects. In the current study, no statistically significant correlation in the bone mineral mass values in the group of children with reduced levels of vitamin D and the group with its physiological concentrations was detected. No correlation between the vitamin D levels and serum levels of parathyroid hormone, calcium and ionised calcium was found. With regard to increasing numbers of studies referring to widespread vitamin D insufficiency, it is necessary to address the issue of its supplementation.