Background: Few studies have assessed 25-hydroxy vitamin D [25(OH)D] status among Italian children.
Objective and hypotheses: To assess 25(OH)D in children and adolescents living in Tuscany, Italy, identifing risk factors for vitamin D deficiency in different age groups.
Method: We evaluated 446 children children and adolescents (2.417.8 years), from Mugello (latitude 44° N), and we determined 25(OH)D, calcium, alkaline phosphatase and parathyroid hormone (PTH) levels. Of these, 275 subjects were selected randomly and followed-up. Subjects with 25(OH)D deficiency were treated with cholecalciferol 10 mcg/day, while those with insufficiency were followed-up improving diet, milks intake, and hours spent outdoors.
Results: Initially 11.4% of subjects had sufficient 25(OH)D, 33.2% insufficient and 55.4% deficient levels. Mean 25(OH)D was 19.08±8.44 ng/ml, with a significant difference between children and adolescents (P<0.0005). Significantly better 25(OH)D levels were observed in the group spending more outdoor hours day (P<0.005), and in children with normal milk consumption (P<0.005). At longitudinal evaluation, 26.9% of subjects had sufficient 25(OH)D, 38.9% insufficient, and 34.2% deficient levels. Mean 25(OH)D was 23.79±6.89 ng/ml. For the subjects supplemented with cholecalciferol, 25(OH)D were significantly higher (P<0.0001) in respect to those not supplemented. Significant differences remained regarding 25(OH)D in the group spending more time outdoors (P<0.005), and in children with normal milk consumption per day (P<0.0001). We found that 25(OH)D levels correlated significantly with age, BMI, cows milk consumption, outdoor physical activity, the use of sunscreens, PTH, and calcium.
Conclusion: The presence of inadequate 25(OH)D levels represents a complex problem involving dietary errors, use of sunscreens, increase in the obesity rate. Neither changes of lifestyle or supplementation with cholecalciferol alone appear to be sufficient to restore adequate levels of vitamin D.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology