ESPE Abstracts

Background: Vitamin D is now recognised as a prohormone, essential for the maintenance of mineral homeostasis, calcium metabolism and normal skeletal architecture. 30 ng/ml or greater can be considered sufficient serum levels. The prevalence of vitamin D deficiency among severely obese children is almost 49% caused by the fact that it is sequestered in the larger body pool of fat of such individuals, being vitamin D fat soluble. Vitamin D deficiency has been recently associated with cardiovascular disease and metabolic syndrome in morbid obesity. Particularly, 25(OH) D levels were inversely correlated with HbA_1c, insulin, LDL, triglycerides, total-cholesterol and insulin resistance.

Objective: To investigate the action of this hormone in obese children visited in Pediatric Endocrinology and Adolescentology Clinic of L’Aquila and to examine the relationship between 25(OH) D concentration and other parameters commonly altered in obesity.

Methods: Prospective study envolving 23 obese children (Ob) (13 girls; 11.06±3.98 years, BMI>95°C) and 21 normal weighted children (C) (12.23±3.54 years). An OGTT was performed and serum insulin was obtained to calculate the glucose/insulin ratio and the HOMA-index. All had undergone an assessment of weight, height and pubertal status; cholesterol, triglycerides, liver enzymes and serum 25(OH) D were measured at the baseline visit.

Results: Mean 25(OH) D levels were highest in Ob, with a statistically significant difference, respect to C. The BMI level was inversely correlated with vitamin D levels. An important inverse relationship was found when vitamin D levels were compared with basal insulin, GPT, GGT, triglycerides.

Conclusions: Comparing the vitamin’s D concentration with the lipemic and metabolic parameters, largely confirm the few existing data in the literature, that such metabolic alterations are linked to a high prevalence of vitamin D deficiency in obese children.