Low Vitamin D Status of Northern Italian Children in Pediatric Primary Care Setting: What to Do?

Aims: To analyze vitamin D status in a group of children living in Northeastern Italy cared by a “family pediatrician”.
Study Design: Cross-sectional study.
Place and Duration of Study: Pediatric primary care in a rural area near Padua (Italy, 45°N latitude), between November 2010 and September 2012.
Methodology: The study was conducted with 113 children (41 girls and 72 boys), aged between 1 and 15 years old. The serum level of 25-hydroxyvitamin D [25(OH)D] was measured using a chemiluminescence immunoassay methodology. Serum 25(OH)D test was included in a panel of laboratory tests ordered for different reasons. A correlation was researched between 25(OH)D level and the following variables: class of age, gender, ethnicity, skin colour, period of blood withdrawal, BMI category, results in other laboratory tests and presence of comorbidity.
Results: Only 26.5% of children had a normal level of 25(OH)D (> 30 ng/ml); in 66.4% of all patients 25(OH)D level was 10-29 ng/ml while 7.1% of children had 25(OH)D < 10 ng/ml. About 40% of all children had 25(OH)D < 20 ng/ml. Non-Italian ethnicity, non-white skin and blood withdrawal in January-March and April-June were significantly associated with hypovitaminosis D [25(OH)D < 30 ng/ml] at univariate level. Both non-Italian ethnicity (P = 0.029) and period of blood withdrawal (P = 0.0062) were also significant at multivariate analysis. The combination of chronic disease or non-white skin could identify only 50% of children with 25(OH)D < 10 ng/ml and 29% of children with 25(OH) < 20 ng/ml.
Conclusion: We noted a high incidence of hypovitaminosis D in asymptomatic children without risk factors. In our region cholecalciferol supplementation should be implemented for all children between October and April. Appropriate dose for children of Northern Italy is debated.