Bone Abstracts

Objectives: To estimate the status of 25-hydroxyvitamin D in healthy Mexican children and to describe factors related to vitamin D deficiency.

Methods: A cross-sectional study was conducted in children 2–14 years old in Mexico City and Toluca Edo de Mexico. Trained interviewers applied a questionnaire including all relevant demographics, medical history, sun exposure, sunblock use and skin phototype. Morning fasting blood was collected in all subjects for estimation of 25-hydroxyvitamin D using Liquid Chromatography-Tandem Mass Spectrometry, and intact parathyroid hormone molecule by radioimmunoassay. Height and weight was obtained to determine body mass index.

Results: A total of 261 children were included in the study, 49.9% were girls (n=129). The sample was divided in preschool (2–5 years; 25.7%), school age (6 to 11 years; 58.4%) and adolescents (≧12 years; 16.0%). According to body mass index per age, 66.3% of the total sample was classified as normal, and 27.8% were overweight/obese. Levels of concentration of 25-hydroxyvitamin D showed an overall median of 26.13 ng/ml and parathyroid hormone of 25 pcg/ml. Vitamin D deficiency (<20 ng/ml) was found in 10% of the sample (n=26), insufficiency (20–29 ng/ml) in 60.9% (n=159) and sufficient levels (>30 ng/ml) in 29.1% (n=76) No correlation was found between 25-hydroxyvitamin D and parathyroid hormone as expected (r=−0.12, R²=0.014, P=0.06). When analyzing possible risk factors for vitamin D deficiency, no statistical association was observed with duration of sun exposure, use of sunblock and skin phototype.

Conclusion: Only 10% of the assessed children in this sample were vitamin D deficient. This prevalence is low when comparing to similar studies reported in Mexico. The type of assay to determine the Vit-D levels might be in part an explanation for the different prevalence numbers, however environmental factors should be further evaluated closely in order to determine wich are the factors influencing the low levels of this vitamin in order to take action towards preventive measurements.

This study was funded with a Grant offered by the Federal Funds of Health in Mexico.

Disclosure: The authors declared no competing interests.